Hi there nice people's of clubknowledge car audio forum! This is my first post so let me quickly introduce what i'm workin on and what i...am.
I've worked on lots of large scale metal art and fabrications in the past but always in far away places (coachella, burning man, cali, down south). I have decided my next "art" project will be for the general enjoyment of my peoples in NYC. This project involves building a mobile sound system and taking it on random (as well as not so random) guerilla parades, through neighborhoods, parks, block parties, etc.
About me: I am a musician/artist and I used to be a studio manager/mixing engineer at a couple of well known "jingle houses" in NY. Over the course of the early to mid 00's I probably mixed a rather impressive percentage of the background music you heard in shampoo, makeup, and other random commercials on your TV's nationwide (and worked on a couple of feature film soundtracks), but I have little to no experience with live sound reinforcement or car audio. Basically, what I'm sayin is, I'm a noob with this stuff specifically, but I should prove to be a very fast learner, we all hope.
Ok so there you have my background. Before I registered here to post looking for advice, I did my research about how to achieve my desired results, and I decided a car system powered off some marine cycle batteries would be nicest. I think one of the major advantages is that I could start small(er) and eventually add speakers and amps and batteries to make everything sound bigger and better as it becomes more affordable to me. Also since i'm not installing inside my car, space is not a limitation for me, as I can custom build cabinets and mount speakers any way I want.
So here is my initial plan:
start with 2 sets of component speakers. From my research it seems like the polk db6501's would fall right into my price range, and would probably sound pretty nice with each getting a channel off an Alpine MRP-F600. In addition I will throw in a 12" sub with a dedicated amp, but have not really nailed that part down yet (I am a busy man and trying to take it 1 step at a time)...
Then I found some nice deals on ebay on Polk MM6's, and thought they might sound even nicer, but I am having trouble finding an amp that I would be comfortable powering those with. I would like to have at least 125w RMS x 4 channels, maybe even 150w, but I can't really find anything nearly as well reviewed or as affordable in terms of an amp.
Surely I will have lots more questions as I struggle through the designs and customizations i have to solve to turn this thing from a dream to reality...but here are the first couple questions I have.
1) Does anybody have any recommendations for a great sounding amp to drive 2 sets of Polk MM6's? Let's say...up to around $250
http://www.polkaudio.com/caraudio/specs/recent/mm6/
2) I am thinking right now sound quality above all, I'm hoping I would definitely be able to pump enough SPL out of such a system for my needs for this summer. So in terms of sound quality and assuming I can't go too far out of the price range I got now, what would sound better? Slightly underpowered MM6's or perfectly matched DB6501's?
Well I hope I didn't bore y'all too badly with my lengthy questions and thanks in advance for any and all help and/or comments.
peax!
Skunk
Replies (33)
swez on 05/27/2009 19:18:27
Read your post and think there are a few more questions before you dive in. Car audio speakers can be strong inside a vehicle. But if you are doing outdoor sound, DJ/Pro systems are a better deal for several reasons. They are more robust and notably more efficient with amplifier power. (120 volts, under 50A's current from an AC source)
A modest AC generator/AC type amplifiers will get the job done if using high efficiency speakers and subs. A set of 3-way Component boxes will do a great job with 1,000 watts of power per channel. You won't need an expensive bank of batteries this way and the AC generator can be covered and dampened to reduce noise.
If you are a DIY'er, consider DJ/Pro gear from www.partsexpress.com. or other sources off ebay or the like. Branded names like JBL, QSC, Carver and Peavey will deliver high SPL values as needed, but not break your piggy bank.
Comments?
Swez
skunk on 05/28/2009 01:04:49
Thanks for you advice Swez. I considered that and i am most definitely a diy'er. I spent some time on parts express and looking at various diy speaker projects but i preferred batteries and a charge and go approach to draggin around and having to bury or insulate a generator. Also just seems simpler as far as speaker design, i figured the component speakers can pretty much stand alone in their housing rather than need a precisely tuned cabinet behind them. And i guess my logic basically came down to, what do they use in mobile things like cars and boats... perhaps i'm just being silly.
I do already have a pair of donated deep cycle batteries. But if it makes that much more sense, then i will take your advice and go with an AC system.
How many batteries do you think something like this would take to play for 6 hours? With a 100w x4 + let's say a 600w sub? Would it be too quiet? i don't care about being the LOUDEST thing in the universe. just want it to sound real nice...
Thanks again!
Skunk
Victor on 05/28/2009 04:02:47
Skunk,
If this audio system needs to be mobile
&
If this is an art project,
Why not try something like this as a car audio art project...?
http://www.box.net/shared/ukv0l4je9o
http://www.box.net/shared/4do6irkhj1
http://www.box.net/shared/m6ejmjqeb6
http://www.box.net/shared/hzua10ayrb
These are all Polk audio Demo Cars.....
If the idea and budget suits you, we can definitely guide you through the entire process, you may need some local help depending on your fabricating skills & availability of tools and materials.
Victor...
Welcome to CK COFFEE
PS: why would you wanna call it a carless sound system, ?
skunk on 05/28/2009 10:54:54
Hi Victor,
those do look pretty deluxe. Thanks for offering to help.
carless is more a description, not what i'm calling it. there is no car - it will be made for walking speeds, most likely in the form of a shopping cart. We want to create both a venue for up and coming artists to get some exposure in a fun and unique way, and of course entertain people. I'm envisioning sort of journeys where you gather a crowd following the cart and eventually lead them to a nice spot where you can park it and have a little concert for a couple hours.
I will do some more thinking about this based on Swez's advice, compare some prices and what not. Just trying to figure out the best way to do it, because i really don't know anybody with experience building something like this.
If I do indeed go with battery/car audio option, this is definitely something along the lines of what I'm looking for, with the exception of the actual car...
swez on 05/28/2009 12:30:17
The nice thing about using car audio gear, it's cheaper than DJ/Pro gear. But, they're not as rugged either. The other challenge to consider is powering the amps for long periods of time off batteries.
If you ran a 1,000 watt system off of batteries alone, it would not take an hour of use before the batteries were depleated and in need of charging. That's why in mobile audio, we depend so much on the Alternator to provide the needed DC power. (Voltage x Amperes = Watts or power)
In this case, you'd need a 12 volt DC motor to power a car ALT that can deliver about 100-120 A's of current to keep things going. The ALT puts out its full power above 2000 RPM. Here, it makes sense to use a pair of Deep Cycle Bats to power a DC motor that spins the ALT at the desired RPM. The question is, how large a DC motor is needed to turn the ALT and still be easy on your batteries? A 1/2 HP motor will draw almost 400 watts alone. (35 amperes is approx current draw for 1/2 HP DC motor) How long will twin batteries last? I don't know that answer.
On AC power amps, the voltage is fixed at ~120 VAC. However, the current draw is about 80% less than DC amp systems for the same power output. This makes things a lot easier to power up the amps and keep the sub(s) bumping too.
Here, the problem is the AC source. There are 2 options.
1. A long power cable plugged into an outlet
2. A tag-a-long portable Generator (Noisy and expensive at that)
This gets pretty complex/expensive as we look deeper, but there are tools to make the plan work. (Plate type amplifers would be a good solution for powering sub[s]) As for powering full range speakers, we'll have to look at other options.
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-752
I'll stop here and let you chew on things a bit OK?
Swez
skunk on 05/28/2009 14:04:36
Wow, that is an excellent and super informative post. I was actually just over here (should be working but instead) playing with the numbers and realized pretty quickly that AC would be nearly 100 times as effective in terms of current draw.
A long power cable as you probably have already gathered is not an option...
Definitely trying to avoid noisy and expensive... but the goal is to build the best sounding (and prettiest) system possible.
If it comes to using a genny, i would build a custom cover so we could easily just drop it on top and contain the noise.
You mention the ruggedness again which has me a little worried but as these will all be installed in custom housing we can do our best to shield the components from the elements and the outside world. i hope.
While i indeed chew on these options with my crew, who i wish were half as helpful and responsive as you guys are (HINT HINT CREW), here is something I mentioned before and wondering about, as far as installation. It seems to me that one difference between component speakers and pro drivers is that the driver is just the mechanical magnet coil cone assembly pretty much. in order to make it effective you would have to calculate and design a tuned speaker cabinet for it. Whereas with the component speakers, they look like they're built on a rather self contained base, so that basically they contain their own speaker cabinet type support already and to make them effective you could just flush mount them into a nice sturdy piece of plywood. Is this true?
swez on 05/28/2009 19:31:13
The sub(s) need to be inside a sealed or ported box that is fitted to the sub makers specs. Depending on the sub size and maker of the sub, a single 12" needs about 1.0 cf of air space inside a sealed box and just under 2.0 cf when ported. I would go ported for the extra low thump around 40 Hz. A nice 15" woofer would be sweet for this project, but the box will also be larger too.
As for mids and highs, they don't need a tuned enclosure per-se. Just something to protect them from the elements and peoples silly fingers would be good. To get good midbass from car speakers, I have found a sealed chamber of 0.03-.08 cf gives nice MB performance to car speakers.
As for box materials, use 3/4" MDF for the box. (MDF = Medium Density Fiberboard) It's low cost, easy to find and cuts very well with a sharp saw blade. When assy is finished, use epoxy or acrylic type paint to protect it against moisture, or vinyl fabric. Normal plywood is not good as it tends to have voids in the plys and will rattle with time, changes in heat and humidity. Baltic birch would be nice, but that stuff is very expensive. (Furniture grade wood)
Hope that helps you and the Crew,
Swez
ttocs on 05/28/2009 22:54:23
wow, this post went fast. I knew a guy at work that did set-up and tear-down at burning man. He told me some stories about this "art festival" that had my chin on my chest.....
How loud are you wanting this to get, and for how long?
Victor on 05/29/2009 03:37:20
In that case, you should take the PA route, instead of car audio....
Victor...
skunk on 05/29/2009 11:39:53
ttocs, your friend at work, if he did set up and tear down, should have some excellent stories indeed. The crew known as DPW (Dangerous People Working) is famous for their antics during the week of the festival. And before and after 50,000 people descend on Black Rock City, things get even crazier. But I don't go to Burning Man anymore for the same reason you put "art festival" in quotes, because it has become more about the partying than the mind blowing art. I have seen (and worked on) some incredible pieces out there though, and one piece that should definitely interest all of you here is the legendary unimog:
http://www.spacecowboys.org/pages/unimog
this thing is INCREDIBLE. a veritable army of sound and visuals, audible for miles in the empty desert.
A couple of pieces I did metalwork and fabrication on, for the curious, include:
http://images.burningman.com/index.cgi?q_keyword=creature+of+the+deep
and
http://images.burningman.com/index.cgi?q_keyword=cleavage+in+space
be careful though, burning man is a very "free spirited" festival so some of those images may be NSFW. if that concerns you, watch out for the blue guy in the image gallery.
So back to the matter at hand, I was up till 3am last night comparing costs and trying to nail or at least narrow down components for AC vs. DC power. I am definitely starting to lean towards AC at this point more than anything just because I know for sure it will easily work for 6+ hours without dying on me. 6 being the absolute minimum, it would be nice to know I can run it for 8-10 hours.
How loud...obviously the louder the better but it's not my top consideration right now. I think starting off with around 1000W system that can be added to in the future is an ideal beginner goal for me. Once I have a bare-bones system at least, we can easily use it to do some fundraising and at that point the project can continue at whatever pace funds allow rather than directly draining my nest egg.
Last night I was looking at the blue wonders project on the parts express gallery: http://www.parts-express.com/projectshowcase/indexn.cfm?project=Blue
Seems to me like a pretty good starting point. I did read it before I started posting here but I reread it last night, because now I can understand more of the technical details of the article. My enclosure design will be completely different, but at least this gives me a starting point for rugged drivers and a more hi-fi sound, which seem to be the goals i'm working towards.
I was thinking that it would be great to build a self contained cabinet for each driver and put them on swiveling hinges so they can have a more omni-directional output while they are stowed into the body but once parked, can all be turned to face in one direction, and fine tuned for perfect imaging. Also that kinda forces us to design a system where each driver is a module, making future swapping or adding a lot easier. Is this possible without complicating crossover design unrealistically?
Here is what I'm thinking:
1 x Subwoofer (bash tech plate?) amplifier
1 x 18" Sub driver (ported enclosure)
2 x 8" Low-MB drivers
2 x 1" tweeters (horn drivers)
each set of MB + Tweeter in it's own sealed enclosure
2-channel amp
1200-2000W generator
y'all smart gents think that looks like a good initial plan? Have i made any glaring omissions? Any suggestions for good compatible and rugged substitutions for the hammer drivers in the blue wonder design?
You guys all rock, thanks again for helping us bring renegade music to the people.
ttocs on 05/29/2009 18:24:50
victor was a nice guy, almost too nice to imagine being in the middle of all the stuff he described. It sounded like a good time if that is was you were there for. He showed pics of some of the more serious stuff there and it looked pretty amazing and was there when they burned the man early(he was not on that side of the camp).
Maybe I missed it earlier, you said that this was not for a car, what kind of vehicle is it?
swez on 05/29/2009 22:29:57
Did some research on 15'' subs from PE. They only listed one Eminence sub that was 4 ohms to match the "Bash" amp mentioned. As I looked at the specs and frequency plots, not really a subwoofer that would go low. Good for PA and guitar, but not so hot for deep bass. We may have to go with a car audio woofer for the sub portion of this plan. A solid 15" should be sufficient at 500 watts.
As for the Mids/Highs, an 8-10" MB/MR driver would be good and a horn type tweeter as well. The trick is matching the speakers well enough so the cone gets most of the power and the tweeters get enough to balance and carry. PE has active and passive crossovers as needed. We can look at various offerings and see what makes the most sense. The Dayton speakers are pretty solid and not overly expensive. They can take a good thrashing compared to most car audio speakers out there.
As for amping the Mid/Highs, a 2 channel that can deliver a solid 100 watts RMS per channel should do the trick. That's a lot of power to very efficient speakers and the Bash amp will do the lows well enough too.
Looked at the Blue Wonders and they are vary similar to stage and DJ rigs we have made in the past. They are a bit large for what you are talking about and probably not very cheap to build either. It's all scalable to whatever needs you have. But the larger the system, portability will be an issue. You'd have to make a cart with large wheels to tote this sucker around.
Comments?
Swez
Victor on 05/30/2009 03:22:38
I would suggest the following
1 - 4-6 ch mixer
2 - Powered 12" or 15" 2 way speakers
3 - Powered Sub 15" , 18" or sub-amp combo..
4 - couple of mics
5 - source CD/ DVD Player
for ex.
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=248-574
http://www.parts-express.com/pe/pshowdetl.cfm?&DID=7&Partnumber=248-6060&ctab=5#Tabs
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=248-6372 + http://www.parts-express.com/pe/showdetl.cfm?Partnumber=245-466
Victor...
PS: Since this audio system will not be in an enclosed acoustic environment, and will be subjected to rough use, wear and tear, weather conditions, and asked to perform in an infinitely huge open space. Going the PA way makes sense.
PA drivers are very different from car audio and home audio drivers, and so are the other equipments.
Although the basics remain the same, each of them perform differently in different acoustic environments, they are designed specifically to perform at their best in a particular environment.
swez on 05/30/2009 11:11:18
Agree with Victor on many point and the mixer is definitely one of them. The Behringer XENYX 502 is compact, but the needed features are there. It is a MONO mixer.
If you have the budget and the space to use 2 enclosures, then you can go stereo with a different mixer. Here, a 2 or 3-way box makes sense. The crossovers are already built into the system and no need to buy/make your own. (A tedious and expensive DIY project averted)
The S1520 or S1530 makes the most sense as they are good to go, right out of the box. These are what we consider DJ main stage or near field Live monitors. Don't let the low RMS wattage numbers trouble you though. Since these speakers are very efficient, it does not take a lot of RMS power to drive them to high SPL numbers.
The Crown amp mentioned is solid and so are QSC's 2 channel amps. A little shopping can net lower prices of e-bay or music stores that cater to musicians and sound reinforcement.
Swez
swez on 05/30/2009 12:14:25
As a follow up, I spoke w/ my brother on what gear he has on hand that might be very useful to your needs. He's going to check hus inventory of subs and other drivers to see if there's anything that would be suitable to your needs.
He did mention a few Electro-Voice 15" recones were on hand and some nice horn systems as well. He suggested a good 2-way plan here with extended range LF woofer and a horn that crosses over at about 2.5-3.0 KHz. Most of his drivers are 8 ohm units.
If you'd like to go that route, we can discuss the details and go from there.
Swez
PS Where are you located? We are in MI. (Western Burbs of Detroit)
skunk on 06/1/2009 15:07:08
Great suggestions guys!
As for CD players, mixers, etc...not too worried about that, I have some stuff lying around and plenty of experience to make all that work. As far as a source, we intend to mostly have live PA artists (in other words, laptop musicians) and local dj's supplying the tunes. I am not quite sure yet how we can fit 2 turntables on it but we will probably come up with some sort of a removable shelf to do that when we need to.
ttocs, I was there that year as well (2007 i think) when they burned the man early. as a matter of fact i was RIGHT THERE talking to some folks and the first of us to notice the fire. It was very enjoyable and amusing, although a lot of people had a lot of extra work to do, to build a new man in time for the big burn. The crazy commando who did it (supposedly as a protest for burning man becoming too commercial) was arrested although i personally felt that was a bit hypocritical to the spirit of freedom that is so touted at the festival...but i suppose less people would attend the event if anarchy truly reigned to that degree.
The vehicle will be a shopping cart.
Swez, a wheel upgrade was indeed one of the first ideas we threw around, we definitely need something better than the lame casters the carts come with to navigate grass or beach sand or really have any kind of versatility. We will probably put trailer tires on it, something actually inflatable.
I live in Jersey City right on the Hudson River, not actually in New York City but that is where we will use it most of the time. Most of my friends live in Brooklyn, there are tons of young adults and young families with children there and I think that is really the type of community that would appreciate and enjoy this type of endeavor.
I was away from my computer all weekend and at work right now, so I will have to take a look at all your suggestions later and see what is most feasible. I was definitely contemplating the 2 way approach, and the blue wonders project is really more a sound reinforcement guideline for driver selection for this. I don't intend to build the same cabinet. I just like his goals for rugged hi-fi sound worthy of a live sound project.
I will take a look at the out of the box options as well, might be perfect and i would like to have the sound components to play with ASAP. But just for the record, i am not the type to shy away from DIY projects or be intimidated by their complexity...on the contrary, i quite relish learning how things around me work at the lowest level. Every time i build something i become a little smarter so no reason to hold back on account of some hard work. After all, isn't that why we're all on this forum?
skunk on 06/1/2009 21:53:34
Ok i just took a look at the Behringer options. Looks like they discontinued the S1520 and S1530 or so it shows on their site. I do think I would prefer the blood sweat and splinters of building customized speakers for individual drivers... but i have been known to bite off a little too much sometimes. i can't say i love behringer from the experience i've had in the past with their mixing gear, but it has been a while, and i know nothing of their PA gear.
The crown looks very deluxe indeed, and i have looked at that QSC a couple days ago, i remember it was about $100 less. Will probably end up going with the cheaper option, after intensive price research.
I am tempted by the easier option here, we will have plenty of work to do even without having to build cabinets for drivers. However, the 2 way system with an external sub kinda feels like the right thing to do, as does 8ohms if we're going the PA route. Gonna have to sleep on this one.
I'm guessing it's pretty easy to integrate a car sub box into an AC system right? Would you just basically need one of those wall wart style adapters for the amp? Or do they make a special beefy one for this type of thing...
skunk
skunk on 06/2/2009 01:08:45
Can't sleep! I will keep tossing and turning until i figure this all out...
Sorry for babbling myself through this process, but it seems to help. Decisions need to be made...so after considering costs of materials for other aspects of the project, i think we will scale back the initial sound system to a more financially realistic level. And despite all my heroic talk earlier about making the job harder on us i have come to my senses and decided there will be plenty work to do without having to build each speaker cabinet from scratch. so....
....after hours of combing endless websites and spec sheets and online stores i find this combination hard to pass up:
http://www.thetwistergroup.com/store/customer/product.php?productid=INT-152%20D42343&source=fr
2 of those with the refurbished qsc
http://www.zzounds.com/item--QSCGX3
We can start with this "modest" $750 system and find a quiet genny and just keep in mind to leave room for a future intergration of a sub.
does this make sense?
swez on 06/2/2009 07:55:47
Well done on the speaker choice, (INT-152's) and a very good price as well. CV has been around a long time, Pro/DJ tested and passed. This package is good as a phase 1 starter kit. Why build a system from scratch when this package has it all for less than most can build it? (Seriously)
If you really want to build from scratch, consider a 18" sub enclosure in the future. This will give the deep lows some added thud to the low end bass below 60 Hz. However, CV's INT-118S seems to fit the bill in form, fit and function for a less than the cost of most Pro Line subs alone. (see JBL's 2242H sub)
http://accessories.musiciansfriend.com/product/JBL-2242H-18-Low-Frequency-Transducer?sku=660073
The trick in fabrication here, building a mobile cart to move all this gear around and the gen-pack to power it all.
Nice,
Swez
The QSC GX3 amp is a solid choice for this phase too. It has the features needed and adequate power to put out some serious SPL too.
skunk on 06/2/2009 16:36:32
Just dropped the loot for the CV's with the GX3 amp. i am realizing that slowly but surely this post is becoming less and less appropriate for this forum, as we're moving away from car audio and more towards live pa, but without all your expertise and guidance it would have taken me weeks and months to figure it out and with probably inferior results.
So if you would like me to I will just leave you alone for more on-topic discussions but if not, once we get all our materials, components and our shopping cart, i can post pics and videos and progress reports here occasionally, until it's done. Unfortunately I can't fully dive into this project for another 2 weeks or so, i have to finish working on my friend's piece first. but i definitely hope to have more or less my drawings and tentative designs done by then.
This is really a great forum, I got genuine, spot on help here, and I hope I didn't annoy too many of the members. I read your contemplations on closing the site down, and i understand the reasoning for it, but as a person who came to the one place where people could help on this great world wide web, i sure would be sad to see this amazing resource go.
Thanks everybody!
skunk
swez on 06/2/2009 21:11:32
Great to see a plan moving in the right direction and timely too.
Keep posting as we are not just car audio anymore. That field seems to be changing and CK will have to adjust as well. (And I believe we will) We try not to turn others away if there are folks on hand who can help. Who knows, we are due for some expansion here. This may be part of it down the road.
Do you have a preamp on hand to mix sources and maybe a mike for announcements too? That would be handy, especially if some EQ were on board too.
No annoyances at all. It's good to have fresh topics here and frankly, car audio can get a bit stale with the same Q/A's all the time. (If you only knew... hehe) Actually, it's been refreshing to poke around in live sound again. When my twin brother lands a big contract and needs more hands on deck, he calls me in for support. I enjoy it and hope for more calls in the future. There's nothing better than working hand in glove with my brother. Yeah, I respect him and have learned a lot too! CLAP
Swez
skunk on 06/3/2009 10:07:31
Swez, i have one of these i'm planning to stick on there right before the amp:
http://www.tcelectronic.com/Finalizer96K.asp
one of our secret weapons back when i was mixing jingles. really sounds great, and has a wizard mode that works surprisingly well and makes it quick and simple to use even for those inexperienced with mixing/mastering.
As for a pre, have not decided how to approach that yet. We will need something - either a full on mixer as suggested above or maybe just a pre of some sort - i think. As far as my own music goes, and as far as i know most laptop musicians these days, all the mixing is done internally in the software and comes out of an audio interface on 2 channels (stereo), which substitutes as a preamp more or less in these cases. Some of those (like mine) also have built in mic pres in case we wanna hook up announcement mics or for live vocals or what have you... but it would be more convenient, and definitely more universal to have a few mixer channels in the equation as you suggest.
I am happy for now to know the speakers are coming, that was the first obstacle to get over. Once we have those we can at least figure out fit and design of the cart, and just be conscious to leave some room for a sub+amp, and leave a few rack spaces for future things like preamps or a small mixer. In my experience with custom projects like this there is tons of planning that you can get bogged down with, and the hardest thing is to get over the inertia and begin to build things. Once you make the first cuts and start putting things together, usually a good crew motivates and the project takes on a life of its own.
swez on 06/3/2009 11:48:51
Hey Skunk,
That tool should help in several ways. The compression, expander and limiter circuits will really take the pressure off the amps and speakers for a more uniform and non-clipped signals. Nice little rack tool.
I still think you'll need a mini-mixer for various input devices. (Input and gain management tool) One thing I have noted is the low gain output that comes from most Laptop sound cards. Am not sure what the gain structure is, but it's well below what my Crown 150 Preamp likes.
I have to lift the volume a lot on the preamp and also the gains on attached amplifiers. When switching from one source to another, it's not seemless or balanced. In fact, it's probably -6dB if not more. That can allow noise to creep in if the system is not very quiet on the front end. (Fortunately, Crown's preamps are pretty quiet and so is the EQ loop the audio runs through before amped)
Agreed, planning is a big part of what you'll be facing when all the parts come in. But as you say, when working with a team of skilled people, ideas flow quickly to break the ice of inertia. It's the synergy of sync'd minds that makes all the difference. (In fact, just having you come here with this project has lifted my own boredom factor) SMILE
It's good to be part of a team that's trying something out on the edge once in a while. Keep up the good work and take your time planning. The rest will all fall into place as needed.
Swez
skunk on 06/5/2009 15:37:54
Swez,
just as an aside, i thought of something the other day. At one point you suggested that a system powered off batteries needs charging and the way to do that would be a motor+alternator setup like in a car. However, these days w/ alternative energy being all the rage i am surprised i didn't immediately think of solar power. Even w/ solar having been around since the 70's or earlier (and having not really improved much in terms of efficiency, only a few %, surprisingly) there are lots of little green solar panel installers popping up everywhere these days, and i'm sure we've all heard about solar powered stages and concerts. I even heard of one a few months ago where the entire concert was human powered by people sitting on stationary bikes and charging up batteries with a dynamo. I suppose it's sort of a boring yet morally satisfying substitute for dancing.
Anyway, i'm not sure solar power would be practical for my own needs. I feel like to get enough charge for even a few hundred watts you'd need to lug around a pretty large panel, and surely they are very expensive. I could be wrong... so i am still gonna do a bit of research since i have a couple of deep cycle batteries and will have plenty of LED's and peripherals to run along w/ the audio. And i'm thinking, even though it's obviously not necessary, would be nice to have the genny exclusively powering the audio, and I could go with a smaller, quieter one, perhaps a 1kW would suffice.
Just wanted to bring up that interesting solar option.
So far i've received 1 of the 2 CV int-152's (i bought them separately) and the amp. The speaker is HUGE!!! I'm gonna have to find a behemoth of a shopping cart. The other should come next week. I am working on my friend's enormous metal sculpture to be installed next week, can't wait for that to be over (sorry friend) so i can start building on this project i've been dreaming about for several years...expect picture updates starting in a couple weeks, i hope!
swez on 06/5/2009 17:02:28
Solar panels are great for large roofs and need a lot of sq ft of them to do some real good. Was reading a few things on them and in time, they can actually pay for themselves if there's enough sunlight in a given geographical area. (Think SW USA) Some efficiency gains are needed to make it practical and the cost of manufacturing reliable panels is not quiet there yet. NASA can afford them. But to get few KW hours, lots of panels are needed.
This will not be an ordinary shopping cart. It seems like a tubular metal frame and large pnumatic tires are part of the game. That would be the lightest and strongest frame I can think of. The CV's weigh 62 lbs each and they are pretty large too. So, 150-200 lbs for the cart is not out of the ballpark. That would be beastly to haul around manually in sand and non-paved surfaces.
IDEA This may sound nutty, but how about a go-cart, electric golf cart or mini-dune buggy to pull it around and carry the ginny? Electric golf carts can be had for decent $$ and can be tricked up as you wish. The main expense are the batteries. These are deep cycle and I believe they put out 48 volts. A fully charged cart will run for 8 hours or more. (Top speed is ~15 MPH) See, I told ya it sounded nutty! LOL
What say you Skunk?
Swez
Victor on 06/6/2009 02:31:08
Sounds nutty, and pretty exciting for a project too... but what about the feasibility and how practical is it ???
instead this is the route I would recommend...
http://www.xantrex.com/web/id/275/p/1/pt/7/product.asp
Victor...
PS: surf the entire site, its got lot of products and information on inverters, generators, solar power, wind power...etc....
swez on 06/6/2009 13:29:58
Interesting thought there Victor. This is an option that's portable, quiet and somewhat efficient too. I like the premise. But we also have some gaps to fill in. When converting voltage from AC to DC or visa-versa, there are some losses in that transaction.
1. Power conversions are not 100% efficient. We have to factor in power losses and how that is compensated for. (5, 10 or 20% loss factors?) We don't know this answer yet.
2. Say we are targeting 1 - 1.2 KW's of power as the load. How much battery power will be needed to keep a system going over a 6-8 hour time period? We don't know that yet either.
3. We do know that a steady 1KW load will drain a 12 volt battery in short order. Once the voltage drops to about 10.5 volts, a typical car amplifier will shut off. Can we assume an inverter will do the same thing? I hope so as an AC powered amp will eventually struggle when voltage drops below design guidelines.
All right, how do we go about calculating the variables before diving in whole hog? Am sure there are published guidelines for this technology. We just need to figure out where to find the answers. Any thoughts?
Swez
skunk on 06/8/2009 10:42:57
Yes that is interesting. Good to know, but i don't want yet another power conversion. I mean PA systems internally are converting from AC to DC so why do it twice? I will probably end up going with an inverter generator, one of the little hondas or yamahas that are super quiet and even try to further muffle the sound with a cover. However I decided that we're gonna just go ahead and build the cart with the system in it and worry about the power later. At some point funding will have to come from elsewhere than my wallet, so we will see.
You're right Swez. It's gonna have to be one beast of a cart. I'm already working on some sketchups...but I have this other project to finish this week, and then, as you say, it's time for the whole hog.
http://sunpluto.net/hive/
swez on 06/8/2009 13:24:06
The small generator makes sense as this may cost less than the DC/AC converter and extra batteries. When choosing the generator, factor in about 30% more power than needed so you can grow the project w/o buying a larger gen.
Since the amp is a moderately low current draw, (Under 10A's at full power) that 1200 watts at full load. If you add a powered sub later, (Plate amp we discussed earlier) that amp draw will factor in as well.
Anyway, finish up your current project and then we'll get back to this as time and funds permit.
Swez
skunk on 06/14/2009 13:57:23
off topic - my friend's project is done and came out great with the world's first fully midi controlled automated gamelan orchestra playing inside! It was pretty spectacular
http://www.globalfunkalliance.com/hive/Hivemind_Gamelatron.mp4
Please excuse my protruding finger, and my loud nonsensical bleating in the beginning of the vid.
swez on 06/14/2009 14:14:58
Fascinating project Skunk!
I liked the droning gong in the background and those spinning do-dads attached to the hive walls. Very creative project and very complex too.
Nice work dude, CLAP
Swez
skunk on 06/18/2009 19:50:03
thanks Swez! The festival was really fun. The sculpture is up on Governor's Island for the whole summer, unfortunately without the gamelatron (http://gamelatron.com/ ) in it but we've just arranged for a party/picnic free event out there in late july to break in the new CV-152's plus the CVA-118 i just grabbed off ebay for under $400!
So that about should do the trick for the shopping cart, i think. In terms of sound system. I have modeled it in sketchup and i think the drawings got a lot of potential. Have to find some shop space and get some metal and wood and casters...I'm very excited to get started but unfortunately work is super busy for me right now and i gotta go away on a business trip soon, so I don't think I can get on it for another 3 weeks or so...
Edit-------------
PS
sorry i'm talking like you're all a buncha new yorkers. for those of you that aren't Governor's Island is a fascinating little place only reachable by ferry. formerly a coast guard training facility it was decommissioned and turned into a park a few years ago. Really nice views of Statue of Liberty, Jersey City, Brooklyn and Lower Manhattan...
swez on 06/18/2009 21:26:18
It's all good! No matter what the venue, the end result is what counts.
When you are ready for the project build, we'll be here and ready to dive in.
Swez
I've worked on lots of large scale metal art and fabrications in the past but always in far away places (coachella, burning man, cali, down south). I have decided my next "art" project will be for the general enjoyment of my peoples in NYC. This project involves building a mobile sound system and taking it on random (as well as not so random) guerilla parades, through neighborhoods, parks, block parties, etc.
About me: I am a musician/artist and I used to be a studio manager/mixing engineer at a couple of well known "jingle houses" in NY. Over the course of the early to mid 00's I probably mixed a rather impressive percentage of the background music you heard in shampoo, makeup, and other random commercials on your TV's nationwide (and worked on a couple of feature film soundtracks), but I have little to no experience with live sound reinforcement or car audio. Basically, what I'm sayin is, I'm a noob with this stuff specifically, but I should prove to be a very fast learner, we all hope.
Ok so there you have my background. Before I registered here to post looking for advice, I did my research about how to achieve my desired results, and I decided a car system powered off some marine cycle batteries would be nicest. I think one of the major advantages is that I could start small(er) and eventually add speakers and amps and batteries to make everything sound bigger and better as it becomes more affordable to me. Also since i'm not installing inside my car, space is not a limitation for me, as I can custom build cabinets and mount speakers any way I want.
So here is my initial plan:
start with 2 sets of component speakers. From my research it seems like the polk db6501's would fall right into my price range, and would probably sound pretty nice with each getting a channel off an Alpine MRP-F600. In addition I will throw in a 12" sub with a dedicated amp, but have not really nailed that part down yet (I am a busy man and trying to take it 1 step at a time)...
Then I found some nice deals on ebay on Polk MM6's, and thought they might sound even nicer, but I am having trouble finding an amp that I would be comfortable powering those with. I would like to have at least 125w RMS x 4 channels, maybe even 150w, but I can't really find anything nearly as well reviewed or as affordable in terms of an amp.
Surely I will have lots more questions as I struggle through the designs and customizations i have to solve to turn this thing from a dream to reality...but here are the first couple questions I have.
1) Does anybody have any recommendations for a great sounding amp to drive 2 sets of Polk MM6's? Let's say...up to around $250
http://www.polkaudio.com/caraudio/specs/recent/mm6/
2) I am thinking right now sound quality above all, I'm hoping I would definitely be able to pump enough SPL out of such a system for my needs for this summer. So in terms of sound quality and assuming I can't go too far out of the price range I got now, what would sound better? Slightly underpowered MM6's or perfectly matched DB6501's?
Well I hope I didn't bore y'all too badly with my lengthy questions and thanks in advance for any and all help and/or comments.
peax!
Skunk
Replies (33)
swez on 05/27/2009 19:18:27
Read your post and think there are a few more questions before you dive in. Car audio speakers can be strong inside a vehicle. But if you are doing outdoor sound, DJ/Pro systems are a better deal for several reasons. They are more robust and notably more efficient with amplifier power. (120 volts, under 50A's current from an AC source)
A modest AC generator/AC type amplifiers will get the job done if using high efficiency speakers and subs. A set of 3-way Component boxes will do a great job with 1,000 watts of power per channel. You won't need an expensive bank of batteries this way and the AC generator can be covered and dampened to reduce noise.
If you are a DIY'er, consider DJ/Pro gear from www.partsexpress.com. or other sources off ebay or the like. Branded names like JBL, QSC, Carver and Peavey will deliver high SPL values as needed, but not break your piggy bank.
Comments?
Swez
skunk on 05/28/2009 01:04:49
Thanks for you advice Swez. I considered that and i am most definitely a diy'er. I spent some time on parts express and looking at various diy speaker projects but i preferred batteries and a charge and go approach to draggin around and having to bury or insulate a generator. Also just seems simpler as far as speaker design, i figured the component speakers can pretty much stand alone in their housing rather than need a precisely tuned cabinet behind them. And i guess my logic basically came down to, what do they use in mobile things like cars and boats... perhaps i'm just being silly.
I do already have a pair of donated deep cycle batteries. But if it makes that much more sense, then i will take your advice and go with an AC system.
How many batteries do you think something like this would take to play for 6 hours? With a 100w x4 + let's say a 600w sub? Would it be too quiet? i don't care about being the LOUDEST thing in the universe. just want it to sound real nice...
Thanks again!
Skunk
Victor on 05/28/2009 04:02:47
Skunk,
If this audio system needs to be mobile
&
If this is an art project,
Why not try something like this as a car audio art project...?
http://www.box.net/shared/ukv0l4je9o
http://www.box.net/shared/4do6irkhj1
http://www.box.net/shared/m6ejmjqeb6
http://www.box.net/shared/hzua10ayrb
These are all Polk audio Demo Cars.....
If the idea and budget suits you, we can definitely guide you through the entire process, you may need some local help depending on your fabricating skills & availability of tools and materials.
Victor...
Welcome to CK COFFEE
PS: why would you wanna call it a carless sound system, ?
skunk on 05/28/2009 10:54:54
Hi Victor,
those do look pretty deluxe. Thanks for offering to help.
carless is more a description, not what i'm calling it. there is no car - it will be made for walking speeds, most likely in the form of a shopping cart. We want to create both a venue for up and coming artists to get some exposure in a fun and unique way, and of course entertain people. I'm envisioning sort of journeys where you gather a crowd following the cart and eventually lead them to a nice spot where you can park it and have a little concert for a couple hours.
I will do some more thinking about this based on Swez's advice, compare some prices and what not. Just trying to figure out the best way to do it, because i really don't know anybody with experience building something like this.
If I do indeed go with battery/car audio option, this is definitely something along the lines of what I'm looking for, with the exception of the actual car...
swez on 05/28/2009 12:30:17
The nice thing about using car audio gear, it's cheaper than DJ/Pro gear. But, they're not as rugged either. The other challenge to consider is powering the amps for long periods of time off batteries.
If you ran a 1,000 watt system off of batteries alone, it would not take an hour of use before the batteries were depleated and in need of charging. That's why in mobile audio, we depend so much on the Alternator to provide the needed DC power. (Voltage x Amperes = Watts or power)
In this case, you'd need a 12 volt DC motor to power a car ALT that can deliver about 100-120 A's of current to keep things going. The ALT puts out its full power above 2000 RPM. Here, it makes sense to use a pair of Deep Cycle Bats to power a DC motor that spins the ALT at the desired RPM. The question is, how large a DC motor is needed to turn the ALT and still be easy on your batteries? A 1/2 HP motor will draw almost 400 watts alone. (35 amperes is approx current draw for 1/2 HP DC motor) How long will twin batteries last? I don't know that answer.
On AC power amps, the voltage is fixed at ~120 VAC. However, the current draw is about 80% less than DC amp systems for the same power output. This makes things a lot easier to power up the amps and keep the sub(s) bumping too.
Here, the problem is the AC source. There are 2 options.
1. A long power cable plugged into an outlet
2. A tag-a-long portable Generator (Noisy and expensive at that)
This gets pretty complex/expensive as we look deeper, but there are tools to make the plan work. (Plate type amplifers would be a good solution for powering sub[s]) As for powering full range speakers, we'll have to look at other options.
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-752
I'll stop here and let you chew on things a bit OK?
Swez
skunk on 05/28/2009 14:04:36
Wow, that is an excellent and super informative post. I was actually just over here (should be working but instead) playing with the numbers and realized pretty quickly that AC would be nearly 100 times as effective in terms of current draw.
A long power cable as you probably have already gathered is not an option...
Definitely trying to avoid noisy and expensive... but the goal is to build the best sounding (and prettiest) system possible.
If it comes to using a genny, i would build a custom cover so we could easily just drop it on top and contain the noise.
You mention the ruggedness again which has me a little worried but as these will all be installed in custom housing we can do our best to shield the components from the elements and the outside world. i hope.
While i indeed chew on these options with my crew, who i wish were half as helpful and responsive as you guys are (HINT HINT CREW), here is something I mentioned before and wondering about, as far as installation. It seems to me that one difference between component speakers and pro drivers is that the driver is just the mechanical magnet coil cone assembly pretty much. in order to make it effective you would have to calculate and design a tuned speaker cabinet for it. Whereas with the component speakers, they look like they're built on a rather self contained base, so that basically they contain their own speaker cabinet type support already and to make them effective you could just flush mount them into a nice sturdy piece of plywood. Is this true?
swez on 05/28/2009 19:31:13
The sub(s) need to be inside a sealed or ported box that is fitted to the sub makers specs. Depending on the sub size and maker of the sub, a single 12" needs about 1.0 cf of air space inside a sealed box and just under 2.0 cf when ported. I would go ported for the extra low thump around 40 Hz. A nice 15" woofer would be sweet for this project, but the box will also be larger too.
As for mids and highs, they don't need a tuned enclosure per-se. Just something to protect them from the elements and peoples silly fingers would be good. To get good midbass from car speakers, I have found a sealed chamber of 0.03-.08 cf gives nice MB performance to car speakers.
As for box materials, use 3/4" MDF for the box. (MDF = Medium Density Fiberboard) It's low cost, easy to find and cuts very well with a sharp saw blade. When assy is finished, use epoxy or acrylic type paint to protect it against moisture, or vinyl fabric. Normal plywood is not good as it tends to have voids in the plys and will rattle with time, changes in heat and humidity. Baltic birch would be nice, but that stuff is very expensive. (Furniture grade wood)
Hope that helps you and the Crew,
Swez
ttocs on 05/28/2009 22:54:23
wow, this post went fast. I knew a guy at work that did set-up and tear-down at burning man. He told me some stories about this "art festival" that had my chin on my chest.....
How loud are you wanting this to get, and for how long?
Victor on 05/29/2009 03:37:20
In that case, you should take the PA route, instead of car audio....
Victor...
skunk on 05/29/2009 11:39:53
ttocs, your friend at work, if he did set up and tear down, should have some excellent stories indeed. The crew known as DPW (Dangerous People Working) is famous for their antics during the week of the festival. And before and after 50,000 people descend on Black Rock City, things get even crazier. But I don't go to Burning Man anymore for the same reason you put "art festival" in quotes, because it has become more about the partying than the mind blowing art. I have seen (and worked on) some incredible pieces out there though, and one piece that should definitely interest all of you here is the legendary unimog:
http://www.spacecowboys.org/pages/unimog
this thing is INCREDIBLE. a veritable army of sound and visuals, audible for miles in the empty desert.
A couple of pieces I did metalwork and fabrication on, for the curious, include:
http://images.burningman.com/index.cgi?q_keyword=creature+of+the+deep
and
http://images.burningman.com/index.cgi?q_keyword=cleavage+in+space
be careful though, burning man is a very "free spirited" festival so some of those images may be NSFW. if that concerns you, watch out for the blue guy in the image gallery.
So back to the matter at hand, I was up till 3am last night comparing costs and trying to nail or at least narrow down components for AC vs. DC power. I am definitely starting to lean towards AC at this point more than anything just because I know for sure it will easily work for 6+ hours without dying on me. 6 being the absolute minimum, it would be nice to know I can run it for 8-10 hours.
How loud...obviously the louder the better but it's not my top consideration right now. I think starting off with around 1000W system that can be added to in the future is an ideal beginner goal for me. Once I have a bare-bones system at least, we can easily use it to do some fundraising and at that point the project can continue at whatever pace funds allow rather than directly draining my nest egg.
Last night I was looking at the blue wonders project on the parts express gallery: http://www.parts-express.com/projectshowcase/indexn.cfm?project=Blue
Seems to me like a pretty good starting point. I did read it before I started posting here but I reread it last night, because now I can understand more of the technical details of the article. My enclosure design will be completely different, but at least this gives me a starting point for rugged drivers and a more hi-fi sound, which seem to be the goals i'm working towards.
I was thinking that it would be great to build a self contained cabinet for each driver and put them on swiveling hinges so they can have a more omni-directional output while they are stowed into the body but once parked, can all be turned to face in one direction, and fine tuned for perfect imaging. Also that kinda forces us to design a system where each driver is a module, making future swapping or adding a lot easier. Is this possible without complicating crossover design unrealistically?
Here is what I'm thinking:
1 x Subwoofer (bash tech plate?) amplifier
1 x 18" Sub driver (ported enclosure)
2 x 8" Low-MB drivers
2 x 1" tweeters (horn drivers)
each set of MB + Tweeter in it's own sealed enclosure
2-channel amp
1200-2000W generator
y'all smart gents think that looks like a good initial plan? Have i made any glaring omissions? Any suggestions for good compatible and rugged substitutions for the hammer drivers in the blue wonder design?
You guys all rock, thanks again for helping us bring renegade music to the people.
ttocs on 05/29/2009 18:24:50
victor was a nice guy, almost too nice to imagine being in the middle of all the stuff he described. It sounded like a good time if that is was you were there for. He showed pics of some of the more serious stuff there and it looked pretty amazing and was there when they burned the man early(he was not on that side of the camp).
Maybe I missed it earlier, you said that this was not for a car, what kind of vehicle is it?
swez on 05/29/2009 22:29:57
Did some research on 15'' subs from PE. They only listed one Eminence sub that was 4 ohms to match the "Bash" amp mentioned. As I looked at the specs and frequency plots, not really a subwoofer that would go low. Good for PA and guitar, but not so hot for deep bass. We may have to go with a car audio woofer for the sub portion of this plan. A solid 15" should be sufficient at 500 watts.
As for the Mids/Highs, an 8-10" MB/MR driver would be good and a horn type tweeter as well. The trick is matching the speakers well enough so the cone gets most of the power and the tweeters get enough to balance and carry. PE has active and passive crossovers as needed. We can look at various offerings and see what makes the most sense. The Dayton speakers are pretty solid and not overly expensive. They can take a good thrashing compared to most car audio speakers out there.
As for amping the Mid/Highs, a 2 channel that can deliver a solid 100 watts RMS per channel should do the trick. That's a lot of power to very efficient speakers and the Bash amp will do the lows well enough too.
Looked at the Blue Wonders and they are vary similar to stage and DJ rigs we have made in the past. They are a bit large for what you are talking about and probably not very cheap to build either. It's all scalable to whatever needs you have. But the larger the system, portability will be an issue. You'd have to make a cart with large wheels to tote this sucker around.
Comments?
Swez
Victor on 05/30/2009 03:22:38
I would suggest the following
1 - 4-6 ch mixer
2 - Powered 12" or 15" 2 way speakers
3 - Powered Sub 15" , 18" or sub-amp combo..
4 - couple of mics
5 - source CD/ DVD Player
for ex.
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=248-574
http://www.parts-express.com/pe/pshowdetl.cfm?&DID=7&Partnumber=248-6060&ctab=5#Tabs
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=248-6372 + http://www.parts-express.com/pe/showdetl.cfm?Partnumber=245-466
Victor...
PS: Since this audio system will not be in an enclosed acoustic environment, and will be subjected to rough use, wear and tear, weather conditions, and asked to perform in an infinitely huge open space. Going the PA way makes sense.
PA drivers are very different from car audio and home audio drivers, and so are the other equipments.
Although the basics remain the same, each of them perform differently in different acoustic environments, they are designed specifically to perform at their best in a particular environment.
swez on 05/30/2009 11:11:18
Agree with Victor on many point and the mixer is definitely one of them. The Behringer XENYX 502 is compact, but the needed features are there. It is a MONO mixer.
If you have the budget and the space to use 2 enclosures, then you can go stereo with a different mixer. Here, a 2 or 3-way box makes sense. The crossovers are already built into the system and no need to buy/make your own. (A tedious and expensive DIY project averted)
The S1520 or S1530 makes the most sense as they are good to go, right out of the box. These are what we consider DJ main stage or near field Live monitors. Don't let the low RMS wattage numbers trouble you though. Since these speakers are very efficient, it does not take a lot of RMS power to drive them to high SPL numbers.
The Crown amp mentioned is solid and so are QSC's 2 channel amps. A little shopping can net lower prices of e-bay or music stores that cater to musicians and sound reinforcement.
Swez
swez on 05/30/2009 12:14:25
As a follow up, I spoke w/ my brother on what gear he has on hand that might be very useful to your needs. He's going to check hus inventory of subs and other drivers to see if there's anything that would be suitable to your needs.
He did mention a few Electro-Voice 15" recones were on hand and some nice horn systems as well. He suggested a good 2-way plan here with extended range LF woofer and a horn that crosses over at about 2.5-3.0 KHz. Most of his drivers are 8 ohm units.
If you'd like to go that route, we can discuss the details and go from there.
Swez
PS Where are you located? We are in MI. (Western Burbs of Detroit)
skunk on 06/1/2009 15:07:08
Great suggestions guys!
As for CD players, mixers, etc...not too worried about that, I have some stuff lying around and plenty of experience to make all that work. As far as a source, we intend to mostly have live PA artists (in other words, laptop musicians) and local dj's supplying the tunes. I am not quite sure yet how we can fit 2 turntables on it but we will probably come up with some sort of a removable shelf to do that when we need to.
ttocs, I was there that year as well (2007 i think) when they burned the man early. as a matter of fact i was RIGHT THERE talking to some folks and the first of us to notice the fire. It was very enjoyable and amusing, although a lot of people had a lot of extra work to do, to build a new man in time for the big burn. The crazy commando who did it (supposedly as a protest for burning man becoming too commercial) was arrested although i personally felt that was a bit hypocritical to the spirit of freedom that is so touted at the festival...but i suppose less people would attend the event if anarchy truly reigned to that degree.
The vehicle will be a shopping cart.
Swez, a wheel upgrade was indeed one of the first ideas we threw around, we definitely need something better than the lame casters the carts come with to navigate grass or beach sand or really have any kind of versatility. We will probably put trailer tires on it, something actually inflatable.
I live in Jersey City right on the Hudson River, not actually in New York City but that is where we will use it most of the time. Most of my friends live in Brooklyn, there are tons of young adults and young families with children there and I think that is really the type of community that would appreciate and enjoy this type of endeavor.
I was away from my computer all weekend and at work right now, so I will have to take a look at all your suggestions later and see what is most feasible. I was definitely contemplating the 2 way approach, and the blue wonders project is really more a sound reinforcement guideline for driver selection for this. I don't intend to build the same cabinet. I just like his goals for rugged hi-fi sound worthy of a live sound project.
I will take a look at the out of the box options as well, might be perfect and i would like to have the sound components to play with ASAP. But just for the record, i am not the type to shy away from DIY projects or be intimidated by their complexity...on the contrary, i quite relish learning how things around me work at the lowest level. Every time i build something i become a little smarter so no reason to hold back on account of some hard work. After all, isn't that why we're all on this forum?
skunk on 06/1/2009 21:53:34
Ok i just took a look at the Behringer options. Looks like they discontinued the S1520 and S1530 or so it shows on their site. I do think I would prefer the blood sweat and splinters of building customized speakers for individual drivers... but i have been known to bite off a little too much sometimes. i can't say i love behringer from the experience i've had in the past with their mixing gear, but it has been a while, and i know nothing of their PA gear.
The crown looks very deluxe indeed, and i have looked at that QSC a couple days ago, i remember it was about $100 less. Will probably end up going with the cheaper option, after intensive price research.
I am tempted by the easier option here, we will have plenty of work to do even without having to build cabinets for drivers. However, the 2 way system with an external sub kinda feels like the right thing to do, as does 8ohms if we're going the PA route. Gonna have to sleep on this one.
I'm guessing it's pretty easy to integrate a car sub box into an AC system right? Would you just basically need one of those wall wart style adapters for the amp? Or do they make a special beefy one for this type of thing...
skunk
skunk on 06/2/2009 01:08:45
Can't sleep! I will keep tossing and turning until i figure this all out...
Sorry for babbling myself through this process, but it seems to help. Decisions need to be made...so after considering costs of materials for other aspects of the project, i think we will scale back the initial sound system to a more financially realistic level. And despite all my heroic talk earlier about making the job harder on us i have come to my senses and decided there will be plenty work to do without having to build each speaker cabinet from scratch. so....
....after hours of combing endless websites and spec sheets and online stores i find this combination hard to pass up:
http://www.thetwistergroup.com/store/customer/product.php?productid=INT-152%20D42343&source=fr
2 of those with the refurbished qsc
http://www.zzounds.com/item--QSCGX3
We can start with this "modest" $750 system and find a quiet genny and just keep in mind to leave room for a future intergration of a sub.
does this make sense?
swez on 06/2/2009 07:55:47
Well done on the speaker choice, (INT-152's) and a very good price as well. CV has been around a long time, Pro/DJ tested and passed. This package is good as a phase 1 starter kit. Why build a system from scratch when this package has it all for less than most can build it? (Seriously)
If you really want to build from scratch, consider a 18" sub enclosure in the future. This will give the deep lows some added thud to the low end bass below 60 Hz. However, CV's INT-118S seems to fit the bill in form, fit and function for a less than the cost of most Pro Line subs alone. (see JBL's 2242H sub)
http://accessories.musiciansfriend.com/product/JBL-2242H-18-Low-Frequency-Transducer?sku=660073
The trick in fabrication here, building a mobile cart to move all this gear around and the gen-pack to power it all.
Nice,
Swez
The QSC GX3 amp is a solid choice for this phase too. It has the features needed and adequate power to put out some serious SPL too.
skunk on 06/2/2009 16:36:32
Just dropped the loot for the CV's with the GX3 amp. i am realizing that slowly but surely this post is becoming less and less appropriate for this forum, as we're moving away from car audio and more towards live pa, but without all your expertise and guidance it would have taken me weeks and months to figure it out and with probably inferior results.
So if you would like me to I will just leave you alone for more on-topic discussions but if not, once we get all our materials, components and our shopping cart, i can post pics and videos and progress reports here occasionally, until it's done. Unfortunately I can't fully dive into this project for another 2 weeks or so, i have to finish working on my friend's piece first. but i definitely hope to have more or less my drawings and tentative designs done by then.
This is really a great forum, I got genuine, spot on help here, and I hope I didn't annoy too many of the members. I read your contemplations on closing the site down, and i understand the reasoning for it, but as a person who came to the one place where people could help on this great world wide web, i sure would be sad to see this amazing resource go.
Thanks everybody!
skunk
swez on 06/2/2009 21:11:32
Great to see a plan moving in the right direction and timely too.
Keep posting as we are not just car audio anymore. That field seems to be changing and CK will have to adjust as well. (And I believe we will) We try not to turn others away if there are folks on hand who can help. Who knows, we are due for some expansion here. This may be part of it down the road.
Do you have a preamp on hand to mix sources and maybe a mike for announcements too? That would be handy, especially if some EQ were on board too.
No annoyances at all. It's good to have fresh topics here and frankly, car audio can get a bit stale with the same Q/A's all the time. (If you only knew... hehe) Actually, it's been refreshing to poke around in live sound again. When my twin brother lands a big contract and needs more hands on deck, he calls me in for support. I enjoy it and hope for more calls in the future. There's nothing better than working hand in glove with my brother. Yeah, I respect him and have learned a lot too! CLAP
Swez
skunk on 06/3/2009 10:07:31
Swez, i have one of these i'm planning to stick on there right before the amp:
http://www.tcelectronic.com/Finalizer96K.asp
one of our secret weapons back when i was mixing jingles. really sounds great, and has a wizard mode that works surprisingly well and makes it quick and simple to use even for those inexperienced with mixing/mastering.
As for a pre, have not decided how to approach that yet. We will need something - either a full on mixer as suggested above or maybe just a pre of some sort - i think. As far as my own music goes, and as far as i know most laptop musicians these days, all the mixing is done internally in the software and comes out of an audio interface on 2 channels (stereo), which substitutes as a preamp more or less in these cases. Some of those (like mine) also have built in mic pres in case we wanna hook up announcement mics or for live vocals or what have you... but it would be more convenient, and definitely more universal to have a few mixer channels in the equation as you suggest.
I am happy for now to know the speakers are coming, that was the first obstacle to get over. Once we have those we can at least figure out fit and design of the cart, and just be conscious to leave some room for a sub+amp, and leave a few rack spaces for future things like preamps or a small mixer. In my experience with custom projects like this there is tons of planning that you can get bogged down with, and the hardest thing is to get over the inertia and begin to build things. Once you make the first cuts and start putting things together, usually a good crew motivates and the project takes on a life of its own.
swez on 06/3/2009 11:48:51
Hey Skunk,
That tool should help in several ways. The compression, expander and limiter circuits will really take the pressure off the amps and speakers for a more uniform and non-clipped signals. Nice little rack tool.
I still think you'll need a mini-mixer for various input devices. (Input and gain management tool) One thing I have noted is the low gain output that comes from most Laptop sound cards. Am not sure what the gain structure is, but it's well below what my Crown 150 Preamp likes.
I have to lift the volume a lot on the preamp and also the gains on attached amplifiers. When switching from one source to another, it's not seemless or balanced. In fact, it's probably -6dB if not more. That can allow noise to creep in if the system is not very quiet on the front end. (Fortunately, Crown's preamps are pretty quiet and so is the EQ loop the audio runs through before amped)
Agreed, planning is a big part of what you'll be facing when all the parts come in. But as you say, when working with a team of skilled people, ideas flow quickly to break the ice of inertia. It's the synergy of sync'd minds that makes all the difference. (In fact, just having you come here with this project has lifted my own boredom factor) SMILE
It's good to be part of a team that's trying something out on the edge once in a while. Keep up the good work and take your time planning. The rest will all fall into place as needed.
Swez
skunk on 06/5/2009 15:37:54
Swez,
just as an aside, i thought of something the other day. At one point you suggested that a system powered off batteries needs charging and the way to do that would be a motor+alternator setup like in a car. However, these days w/ alternative energy being all the rage i am surprised i didn't immediately think of solar power. Even w/ solar having been around since the 70's or earlier (and having not really improved much in terms of efficiency, only a few %, surprisingly) there are lots of little green solar panel installers popping up everywhere these days, and i'm sure we've all heard about solar powered stages and concerts. I even heard of one a few months ago where the entire concert was human powered by people sitting on stationary bikes and charging up batteries with a dynamo. I suppose it's sort of a boring yet morally satisfying substitute for dancing.
Anyway, i'm not sure solar power would be practical for my own needs. I feel like to get enough charge for even a few hundred watts you'd need to lug around a pretty large panel, and surely they are very expensive. I could be wrong... so i am still gonna do a bit of research since i have a couple of deep cycle batteries and will have plenty of LED's and peripherals to run along w/ the audio. And i'm thinking, even though it's obviously not necessary, would be nice to have the genny exclusively powering the audio, and I could go with a smaller, quieter one, perhaps a 1kW would suffice.
Just wanted to bring up that interesting solar option.
So far i've received 1 of the 2 CV int-152's (i bought them separately) and the amp. The speaker is HUGE!!! I'm gonna have to find a behemoth of a shopping cart. The other should come next week. I am working on my friend's enormous metal sculpture to be installed next week, can't wait for that to be over (sorry friend) so i can start building on this project i've been dreaming about for several years...expect picture updates starting in a couple weeks, i hope!
swez on 06/5/2009 17:02:28
Solar panels are great for large roofs and need a lot of sq ft of them to do some real good. Was reading a few things on them and in time, they can actually pay for themselves if there's enough sunlight in a given geographical area. (Think SW USA) Some efficiency gains are needed to make it practical and the cost of manufacturing reliable panels is not quiet there yet. NASA can afford them. But to get few KW hours, lots of panels are needed.
This will not be an ordinary shopping cart. It seems like a tubular metal frame and large pnumatic tires are part of the game. That would be the lightest and strongest frame I can think of. The CV's weigh 62 lbs each and they are pretty large too. So, 150-200 lbs for the cart is not out of the ballpark. That would be beastly to haul around manually in sand and non-paved surfaces.
IDEA This may sound nutty, but how about a go-cart, electric golf cart or mini-dune buggy to pull it around and carry the ginny? Electric golf carts can be had for decent $$ and can be tricked up as you wish. The main expense are the batteries. These are deep cycle and I believe they put out 48 volts. A fully charged cart will run for 8 hours or more. (Top speed is ~15 MPH) See, I told ya it sounded nutty! LOL
What say you Skunk?
Swez
Victor on 06/6/2009 02:31:08
Sounds nutty, and pretty exciting for a project too... but what about the feasibility and how practical is it ???
instead this is the route I would recommend...
http://www.xantrex.com/web/id/275/p/1/pt/7/product.asp
Victor...
PS: surf the entire site, its got lot of products and information on inverters, generators, solar power, wind power...etc....
swez on 06/6/2009 13:29:58
Interesting thought there Victor. This is an option that's portable, quiet and somewhat efficient too. I like the premise. But we also have some gaps to fill in. When converting voltage from AC to DC or visa-versa, there are some losses in that transaction.
1. Power conversions are not 100% efficient. We have to factor in power losses and how that is compensated for. (5, 10 or 20% loss factors?) We don't know this answer yet.
2. Say we are targeting 1 - 1.2 KW's of power as the load. How much battery power will be needed to keep a system going over a 6-8 hour time period? We don't know that yet either.
3. We do know that a steady 1KW load will drain a 12 volt battery in short order. Once the voltage drops to about 10.5 volts, a typical car amplifier will shut off. Can we assume an inverter will do the same thing? I hope so as an AC powered amp will eventually struggle when voltage drops below design guidelines.
All right, how do we go about calculating the variables before diving in whole hog? Am sure there are published guidelines for this technology. We just need to figure out where to find the answers. Any thoughts?
Swez
skunk on 06/8/2009 10:42:57
Yes that is interesting. Good to know, but i don't want yet another power conversion. I mean PA systems internally are converting from AC to DC so why do it twice? I will probably end up going with an inverter generator, one of the little hondas or yamahas that are super quiet and even try to further muffle the sound with a cover. However I decided that we're gonna just go ahead and build the cart with the system in it and worry about the power later. At some point funding will have to come from elsewhere than my wallet, so we will see.
You're right Swez. It's gonna have to be one beast of a cart. I'm already working on some sketchups...but I have this other project to finish this week, and then, as you say, it's time for the whole hog.
http://sunpluto.net/hive/
swez on 06/8/2009 13:24:06
The small generator makes sense as this may cost less than the DC/AC converter and extra batteries. When choosing the generator, factor in about 30% more power than needed so you can grow the project w/o buying a larger gen.
Since the amp is a moderately low current draw, (Under 10A's at full power) that 1200 watts at full load. If you add a powered sub later, (Plate amp we discussed earlier) that amp draw will factor in as well.
Anyway, finish up your current project and then we'll get back to this as time and funds permit.
Swez
skunk on 06/14/2009 13:57:23
off topic - my friend's project is done and came out great with the world's first fully midi controlled automated gamelan orchestra playing inside! It was pretty spectacular
http://www.globalfunkalliance.com/hive/Hivemind_Gamelatron.mp4
Please excuse my protruding finger, and my loud nonsensical bleating in the beginning of the vid.
swez on 06/14/2009 14:14:58
Fascinating project Skunk!
I liked the droning gong in the background and those spinning do-dads attached to the hive walls. Very creative project and very complex too.
Nice work dude, CLAP
Swez
skunk on 06/18/2009 19:50:03
thanks Swez! The festival was really fun. The sculpture is up on Governor's Island for the whole summer, unfortunately without the gamelatron (http://gamelatron.com/ ) in it but we've just arranged for a party/picnic free event out there in late july to break in the new CV-152's plus the CVA-118 i just grabbed off ebay for under $400!
So that about should do the trick for the shopping cart, i think. In terms of sound system. I have modeled it in sketchup and i think the drawings got a lot of potential. Have to find some shop space and get some metal and wood and casters...I'm very excited to get started but unfortunately work is super busy for me right now and i gotta go away on a business trip soon, so I don't think I can get on it for another 3 weeks or so...
Edit-------------
PS
sorry i'm talking like you're all a buncha new yorkers. for those of you that aren't Governor's Island is a fascinating little place only reachable by ferry. formerly a coast guard training facility it was decommissioned and turned into a park a few years ago. Really nice views of Statue of Liberty, Jersey City, Brooklyn and Lower Manhattan...
swez on 06/18/2009 21:26:18
It's all good! No matter what the venue, the end result is what counts.
When you are ready for the project build, we'll be here and ready to dive in.
Swez
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