So, here's what I have, what I want and what I'd like to do... any and all ideas would be greatly appreciated.
1990 Ford Bronco II
Alpine 9847 HU
MB Quart QSD 216 6.5" Comp (front)
Factory 5x7 in the back
I want a decent 4 channel amp that I'm going to install custom in the cargo area (lots of windows, so I have to get creative in hiding everything so nothing gets stolen). I'm planning on running the front speakers off the first 2 channels, bridging the second 2 to power one 10" sub, and leaving the back speakers running off the power from the HU itself. The reason for this is that my 1yo daughter sits back there and there's really no reason to have it louder/nicer/better/etc.
I'm planning on installing the sub inside the side panel of the trunk, so it can't be a really deep sub. I'm going to remove a portion of the interior paneling and fab a box that sits in there and looks like it's part of the vehicle. But due to the size of the cargo area, I don't really have a lot of availible space.
I'm trying to do all of this fairly inexpensivly, but I would like it to sound good. I'm a lot more interested in SQ than SPL, especially because of the baby.
Any suggestions would be greatly appreciated, I can't make up my mind at all. There's just so many products out there, it's getting harder and harder to find the decent products though the mess of total junk.
Replies (28)
lilschtive on 07/17/2006 13:58:45
tight space, but want nice bass? Jl audio realesed a new sub made for small conditions..with a 10'' sub being only 4 3/4inches deep! you might be interested if putting into a door panel:
http://mobile.jlaudio.com/products_subs.php?series_id=15
emoboywyl on 07/17/2006 14:05:10
Is this an SVC or DVC sub?
swez on 07/17/2006 22:24:41
This is a 4 ohm SVC.
Power handling is modest but adequate for some decent thump. (125-150 watts RMS)
JL recommends a 0.65 cf internal airspace for a sealed enclosure. Pretty compact for a 10" sub too.
Amp wise, your MBQ's take a good deal of power if you want them loud. However, a 4 channel amp that can deliver a solid 75 watts RMS x 4 @ 4 ohm loads should suffice. The rear channels can be bridged for sub applications and the front channels are should be full range.
What price range are you thinking for an amp?
Swez
PS This truck has lots of windows. Consider tinting the rear windows for privacy and some degree of theft protection. If the amp is small enough, consider mounting it under the front seat. (The side where the child cannot spill stuff on it) Sodas, juice, formula and water are very bad for amplifiers.
emoboywyl on 07/18/2006 00:46:36
I'll try and describe my deisgn concept for the rear cargo area as best I can.
I'm going to cut a piece of 1/2" plywood the shape of the entire cargo area, and permanently bolt it to the frame of the truck. I'll run 2x4's around the perimiter on end for a frame. I'm going to build three seperate partitions, two side by side in the front, and one running along the back. I'll mount the amp in the right front partition and bolt it to the plywood with security bolts. (The left partition I'm going to leave empty in case I ever decide to upgrade and add a second amp) The back partition I'm going to use as a heat transfer and air exchange area, by mounting fans blowing into and away from the amp. I'm also looking at running conduit from my a/c vent line into that area. (I live in phoenix, and the heat here is very bad for amplifiers as well)
On top of all this I'll lay a piece of 1/4" plywood with a section cut out directly above the amp. Then I'm going to strech some grey silt mesh fabric over the top of it that matches the color of the interior upholstry. The windows are already slightly tinted, and if I do this right you wouldn't even be able to tell that there's anything but empty cargo space there when you're looking into it from outside. But the mesh top and the air exchange will allow the amp to keep nice and cool (or at least as cool as can be expected).
Wow, that was a lot. Now about the box. If I give you the space I have to work with, can you give me the design measurements for the box?
I'm going to remove the vinyl/plastic paneling on the left side of the cargo area and build the box up against the frame of the car (well dynamatted) and again paint it and cover it in grey mesh, so again it'll look like part of the car.
The spacial diamentions for the box that I have availible are as such... tell me if this is workable for .65.
14.5"w x 13.5"h x 6"d
I can play with the depth a little bit, but not a lot. Can you first tell me if this is workable, and if so, can you give me the design specs for the box.
I'm planning on spending between $250-300 for the amp, although I'd be happy going with less. I'm really not that concerned with the best quality right now, I'd like something decent, but it doesn't have to be great. I already have great speakers in the front, I really like that sub, but I have no idea what amp to get.
Ok, I'm done, you can breathe now. =)
Thanks for your time, opinions and advice in advance.
Wyl
lilschtive on 07/18/2006 01:18:54
Would a 250/1 JL audio amp work for this system?
(( http://cgi.ebay.com/JL-Audio-250-1-Monoblock-SUB-AMP-NEW-2006-SLASH-SERIES_W0QQitemZ300007556474QQihZ020QQcategoryZ79827QQrdZ1QQcmdZViewItem#ebayphotohosting))
250 W RMS @ 1.5W-4W ??
emoboywyl on 07/18/2006 02:08:33
Now, I really like the slash series amps, but I'm not even considering using a seperate sub amp for a while at least...
but thank you
Plus, what's with all the negative feedback on that seller?
swez on 07/18/2006 10:03:34
Have read about others using a false flooring plan for small SUV's and such. It's a workable plan, if you can keep the amp(s) cool enough.
Some take it one step further and integrate their sub enclosure into such designs. If this makes sense to you, the best location is generally behind the rear seat. You can aim the sub toward the tailgate, make it fire up toward the roof or even down-firing, so the sub is completely hidden from view. (this method is very stealthy)
The sub dimensions noted above, net out to 0.45 cf internally, assuming 5/8" wood thickness. That might be usable for an 8" sub, but few 10's can do well in that size enclosure. (loss of deep bass performance)
14.5"w x 13.5"h x 6"d = 1175 in^3/1728 = 0.68 ft^3 (external)
The internal dimensions calculate out to a net 0.45 ft^3.
The JL 8W0-4 is an option here. The internal airspace volume needed for this sub is a mere 0.375 ft^3. Power handling is also 125 watts RMS and you'll get most of the lower octave of bass here. This is a 4 ohm SVC sub as well.
http://mobile.jlaudio.com/pdfs/9183.pdf
As for amping your front speakers, (MBQ's) and a single sub, the JL 300/4 is a very good option. This nets a solid 75 watts RMS x 2 from the front channels and 150 watts RMS from the rear channels when bridged MONO for the sub.
http://mobile.jlaudio.com/products_amps.php?amp_id=254
Comments?
Swez
emoboywyl on 07/18/2006 13:30:31
How about, keeping the hight and width constant, what would the depth of the box have to be to achieve .65cf? Going off the formula you typed, if I expanded the depth of the box to 8" that should achieve the desired amount of airspace, correct?
I really like the 300/4, but that's kinda at the very high end of my budget spectrum... what else is there that would do a good job, but not totally break the bank?
Ash on 07/18/2006 19:50:10
Don't mean to shake things up here but, if your going for SQ, you need to be aware of a few things.
1. If your going to use a low power sub, then you need to make
sure it will match the transfer function/cabin gain of the vehicle.
This will take place when choosing a proper F3 cutoff (hertz at
-3 db). If it picks up around 60hz, believe it or not a 65-80hz
cutoff would work good factoring in a lo-pass crossover @
80hz and under. Too low a F3, and you get exaggerated bottom
end.
2. For SQ, in order to get a "smooth" low frequency range and
proper blend with front speakers, a rather low Qtc around .707
or less should be used. This will help attenuate upper bass
and keep from drawing from "up front bass".
This being said it is quite easy for the wrong sub to be used. With your internals being around .45cft, I would suggest finding a sub that will meet the low QTC requirement in that available space. Else, you could end up with a sub that is overly robust and hard to tame. At the same time you won't be wasting precious limited power trying to produce lower frequencies.
swez on 07/18/2006 20:09:43
Good point there Ash and you have a lot more experience with transfer function and resonance properties then most guys here do.
Here's the T/S specs of the JL 8W0-4. Care to run them through WinISD for some basic plots? This is a medium size SUV type vehicle. So, transfer function will definitely be a factor below about 55 Hz.
Am thinking JL often specs a Qtc >0.7 for their subs. But, I'd like your read on this one as well. One of these days, I'll get my butt in gear and learn how to use WinISD. Which version is best out there now?
http://mobile.jlaudio.com/pdfs/9183.pdf
Swez
Ash on 07/18/2006 20:48:51
The Alpha version is more accurate on plots, but is harder to work with. I do like the fact that you can simulate response with inlcuded crossovers. I still like using beta for it is simple and quicker. You just have to guesstimate the other factors.
The JL 8W0-4 is not a bad sub, I just worry about the power handling at lower QTC's. I imagine JL spec'ed this one's 75rms nom @ .707Qtc. 125rms for higher Q's.
It's xmax is also somewhat limited (only 6.8mm) although F3 starts @ 59hz even at Qtc-1.0, which is good. Yet, I think this would be too much a robust/snappy setup just to attain full power handling of 125.
All this coupled with a 85db sensitivity makes for a sub in need for a pair to work good at low Q's in my book. Probably would work better in a compact hatchback or low volumes if standing alone.
swez on 07/18/2006 21:09:17
Thanks for the inputs there Ash! CLAP
I would agree that this would probably be a very punchy sub for the reasons mentioned. That's one reason I thought about a down-firing application here. Facing the sub downward and into a carpeted and/or padded floor, will tend to absorb some of the snappy/punchiness of a smaller cone design. Oddly enough, thick carpets/padding will tend to absorb upper bass hot spots and make the sub sounb more smooth in the 60-100 Hz., range.
Try this one out and see for yourself. A nice woolen blankie placed in front of the sub cone, really attenuates upper bass and mids. A few layers of material do a pretty good job. Yes, it may seem hoakie and red-necked to some... but it actually works out well.
Swez
emoboywyl on 07/19/2006 01:49:45
Wow, that's awesome... I can draw a rudimentary design of what I'm trying to do with it, how can I post that or send it?
Which the dimensions and ideas in mind, I can work on how to best place the sub, so it's operating most efficiently, sounds the best, and is well concealed.
Also, I'm not dead set on this sub. I don't own it yet or anything, it was just a previous suggestion. Is there one that would work better for my applications? The 8" maybe? Or maybe just something different.
My problem with mounting the sub so that it's downfiring is still going to be space. Once you see the layout, you'd understand what I mean...
You guys are really helpful, thank you. I have so many ideas running through my head, it's hard to know what's practical and what would acctually work in the real world.
swez on 07/19/2006 06:33:46
A little wild brainstorming is always a good place to start a new project. After all the ideas are on the table, some will step out as highly workable. Others will prove too far out of the box and not worth pursuing. Avoid getting stuck on impractical options that draw your needed focus away from reaching the intended goal.
Many of our guys post pictures on photobucket or similar free sites. If you have sketches and drawings to share, use a format that is easily opened and viewed by those trying to help out. MS Paint is fair for such things.
Have used Power Point for many detailed drawings and sketches. It does a very good job with diagrams, text and other sketch related tasks. All one needs is a Power Point reader or have it as parts of the MS bundled software we often get with a computer OS like Win XP. Those files are best shared via direct e-mails.
There are plenty of 8" subs out there to consider. Just have to balance power handling, enclosure space needs, cost and low bass performance characteristics. A 0.35 - 0.5 ft^3 enclosure is very compact, but when we factor in the board thickness and box constuction, realize the exterior dimensions are about 20-30% larger than internal airspace required by the sub. The more we can hide that box in the sub-flooring, the less protrusion we'll see.
A few words about down-firing sub designs:
1. They work well when designed/integrated properly
2. We get a very stealthy install
3. The angle of the sub in relation to the floor, matters a lot
4. Need an enclosure to give the sub adequate airspace
Comments?
Swez
Ash on 07/19/2006 20:59:05
One suggestion that would also be worth considering is this:
http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=295-550&ctab=10#Tabs
Check out it's recommended box that would fit well into the space you want:
http://www.partsexpress.com/pdf/295-550%20sealed.pdf
The F3 is a little on the high side but this does not present a problem when crossover and transfer function is factored in. Sensitivity is decent (around 89db @1w/1m) and will make good use of a 4 channel amp system.
I recently installed one in my niece's Sebring. Located in the rear corner facing toward the opposite side of the trunk; the sub was very out of the way with tunable results. Low end was not lacking by far, though driven by a weakling overated Sony Xplod 800 4 channel.
swez on 07/19/2006 23:13:00
That sub may be a very good option for you embo. The enclosure size is certainly compact enough and you can manipulate the H,W & D dimensions as needed too.
The price is very good for a woofer of this calibur and the compact enclosure needs are a very good fit too. You can easily come up with an 4,5 or 6 channel amp to power everything as needed and not be a huge current drain on the electrical system either.
Swez
emoboywyl on 07/20/2006 02:49:07
Wow, thank you for that sketch and specs!
I acctually had so much of a blast doing all of this, and with the other stuff I had installed in my car and my mom's car, that after spending the weekend researching car stereo online I drove over to my local shop and convinced them to give me a job.
I know I don't really know much, but the guys there are pretty cool and they're more than welcome to show me everything and let me try to figure stuff out on my own, which is great!
I think all of these "wild brainstormings" have really piqued a natural interest of mine.
I have a couple of questions for you, because you guys are so incredibly helpful and knowledgeable and because I know you'll be more impartial than the guys that work at the shop.
Since I can get things at cost now, I want to know if the equiptment they sell is worth purchasing, since it's so cheap. Unfortunatly, it's quite a limited variety of brands. Here's the amp I was thinking about buying:
http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=15526
I think I'd pay about $105 out the door for that.
And the sub, I'd pay about $25:
http://www.crutchfield.com/S-fspTHx6YWoV/cgi-bin/prodview.asp?i=607X104SX
Feel free to be totally honest, I'm more interested in buying products that are worth my money, rather than total crud, just because it's inexpensive.
I just want to know what's worth buying and what's not.
Ash on 07/20/2006 04:41:19
That amp is a solid one. If you got it, I think you will have it for a long time and be happy with it.
As for the sub. I don't like it. Fs is too high for a 10". Not to mention even though it will fit in a small box, it will be at the cost of smoothness. The small box range for this one is on the high Q side. I'm taking that this is a SPL sub and not a SQ.
emoboywyl on 07/20/2006 10:36:24
Cool, thank you!
I'll pick up the amp today, and forget about the sub.
I'll take a good hard look at that sub you posted my the link for. Like I said, it's not worth spending a few bucks less if it's going to sound like **** in the end.
swez on 07/20/2006 15:43:30
Ditto! Grab the amp, look at the Dayton Quatro sub mentioned earlier. I think you will be very please with that combonation and the front channels are enough to power your MBQ's too.
Yes, the MBQ's like more power, but this is a good start.
Swez
emoboywyl on 07/21/2006 02:32:12
As soon as I get the money together I'd really like to buy a JL 450/4
Then as I do other related work on the car, I want a JL 500/1 seperatly to power the sub, and a pair of MB 6x9 for rear fill.
swez on 07/21/2006 13:44:42
That JL 450/4 has a few interesting features in it. It uses a highly regulated power supply, requires a 60A fuse and nets the following
output values:
4 channels, Stereo mode:
1. Front channels: 150 W RMS x 2 @ 1.5 ohm – 4 ohm (11 – 14.5V)
2. Rear Channels: 75 W RMS x 2 @ 1.5 ohm – 4 ohm (11 – 14.5V)
You can also bridge front or rear channels for powering subs too. Not the most efficient way to use this amp, but it will work if you wish to do that.
Note the rear channels have 50% less RMS power than the front channels do, on this amp. No need to go and spend big money on high end rear speakers either. A solid pair of 2-way Coaxials will do the job here. Put your best speakers up front as this is where you'll get the biggest bang for your buck.
The 500/1 is a very strong sub amp. It is very efficient with input power as it's a Class D MONO amp. This amp should be fused at 50A's. So, when you add everything up, these amps will need a minimum of #4 gage wiring from the BAT to a Distribution Block. Then, you can use #8 gage wires to each amp and #8 grounds too.
If you're running longer than 12 feet of #4 power wire on this truck, drop to #2 gage main wire and use #4 or #8 wire to feed your amps off the D-block. Use a fused D-block as these amps do not have internal/external fuses.
FYI: To conserve on power consumption from the amps, consider the JL 300/4 as an option. It delivers 75 watts RMS x 4 and if you use fairly efficient speakers, that is plenty of power to gain high SPL and very good clarity too. This amp only needs a 40A fuse and you can still use the 500/1, but stay with #4 power feeds and # 8 wires for each amp.
This option will provide plenty of clean power and save you the added costs of a larger amp, bigger wires and easier on your electrical system as well/
Comments?
Swez
emoboywyl on 07/22/2006 02:09:21
I've got the MB Quart QSD 216's in the front.
I'm not really all that interested in the rear speakers, since it's just my daughter back there, and with the placement of the quarts I don't really hear any difference when they're on.
So, what do you think about Soundstream bringing back the little blue reference series amps? The old ones are incredible, I wonder about the new ones... will they be as good?
If so, I might just wait till we get some at our shop and buy me one of the 800.2 for my Quarts and a 400.1 for the sub.
What do you think?
emoboywyl on 07/22/2006 03:01:10
Also, since I'd just be using the 500/1 paired with the 10wv2-8 DVC I think/hope. I'd wire that in series to 4ohm. Or the 10" Dayton at 4ohm.
I'm really just using the sub for balance, rather than punch. I don't want to hear the base over the rest of the music, but rather have it even and balanced so the music is as clear and vibrant as possible.
So I guess the question here is, is the 500/1 excessive? I know the Quarts love power, and I'm more than happy to feed them that, but would the 250/1 be sufficient, or would it really be worth it to go with double the power?
This question also in relation to the previous one about the Soundstream amps... I'd like to know your opinions about this setup and those amps.
swez on 07/22/2006 09:15:51
As for bass, the 250/1 has plenty of power to bump when you want it, but will not knock the baby out of his/her car seat either. SMILE This amp will deliver about 3dB less power (SPL) to a sub than its bigger brethren. (JL 500/1) Less current is needed too. A single sub that can manage 250-300 watts RMS and has a coil impedence between 1.5 - 4.0 ohm is fine. It does not have to be a pricey JL sub either. There are many fine subs out there that fit this need for under $150.00.
If only powering the MBQ's and no rear speakers, the JL 300/2 is a very good choice. Plenty of RMS power for clean mids/highs and adequate midbass too.
About SoundStream products... they were once considered a top tier brand name and had the prices to match. They changed hands about 4-5 years ago and have now expanded from the older premium lines, to several very affordable new products as well.
I'd love to get my hands on a few of the new products and test them out just to see how they stack up with other great brands we now see out there. The older amps and such, (Circa 2000 and older) were pretty much bullet proof and some of the cleanest amps around. The new products are probably still very good. However, they have now gone to a mass-marketing program, added more products and lower prices have put this venerable brand in reach of the average consumer.
How/why did they make that change?
1. Lower cost due to lowered profit margins?
2. Automated assy precesses?
3. Off shore labor?
4. Use cheaper and fewer internal components???
The short answer is... probably still a very good product line to consider for high end "Audiophile" installs. Are they up to par with other amps in the same price range? (probably equal to, or better than most branded names in same price class)
Again, hands on experience with the newer products, would be a definite plus.
Swez
emoboywyl on 07/23/2006 00:54:36
That's kinda what I was expecting...
I'll definatly be able to get my hands on one when they arrive, I'd love to play around with it some and check out how it sounds. The great part is that I'll be able to do that on someone else's car before I go and spend the money on one.
This really is a fun industry to work in, albeit a very dirty one. It's like I'm getting paid to work on a hobby! =)
swez on 07/24/2006 10:32:40
If you are young, small in frame and can climb around inside tight spaces for hours at a time, this is a very good job. Big guys have a much harder time doing this kind of work.
Know what ya mean about turning a hobby into a money maker. If we love what we do and get paid to do it, it doesn't get much better than that.
Keep up the good work and learn as much as you can,
Swez SMILE
emoboywyl on 07/24/2006 14:06:04
well, not too small in frame, but I make do! =)
I'm workin hard, although that doesn't seem the norm for the shop I work at!
I want to learn as much as I can, that's why I keep asking, and sharing my newfound knowledge here. as well! Thanks for all the insight!
Wyl
1990 Ford Bronco II
Alpine 9847 HU
MB Quart QSD 216 6.5" Comp (front)
Factory 5x7 in the back
I want a decent 4 channel amp that I'm going to install custom in the cargo area (lots of windows, so I have to get creative in hiding everything so nothing gets stolen). I'm planning on running the front speakers off the first 2 channels, bridging the second 2 to power one 10" sub, and leaving the back speakers running off the power from the HU itself. The reason for this is that my 1yo daughter sits back there and there's really no reason to have it louder/nicer/better/etc.
I'm planning on installing the sub inside the side panel of the trunk, so it can't be a really deep sub. I'm going to remove a portion of the interior paneling and fab a box that sits in there and looks like it's part of the vehicle. But due to the size of the cargo area, I don't really have a lot of availible space.
I'm trying to do all of this fairly inexpensivly, but I would like it to sound good. I'm a lot more interested in SQ than SPL, especially because of the baby.
Any suggestions would be greatly appreciated, I can't make up my mind at all. There's just so many products out there, it's getting harder and harder to find the decent products though the mess of total junk.
Replies (28)
lilschtive on 07/17/2006 13:58:45
tight space, but want nice bass? Jl audio realesed a new sub made for small conditions..with a 10'' sub being only 4 3/4inches deep! you might be interested if putting into a door panel:
http://mobile.jlaudio.com/products_subs.php?series_id=15
emoboywyl on 07/17/2006 14:05:10
Is this an SVC or DVC sub?
swez on 07/17/2006 22:24:41
This is a 4 ohm SVC.
Power handling is modest but adequate for some decent thump. (125-150 watts RMS)
JL recommends a 0.65 cf internal airspace for a sealed enclosure. Pretty compact for a 10" sub too.
Amp wise, your MBQ's take a good deal of power if you want them loud. However, a 4 channel amp that can deliver a solid 75 watts RMS x 4 @ 4 ohm loads should suffice. The rear channels can be bridged for sub applications and the front channels are should be full range.
What price range are you thinking for an amp?
Swez
PS This truck has lots of windows. Consider tinting the rear windows for privacy and some degree of theft protection. If the amp is small enough, consider mounting it under the front seat. (The side where the child cannot spill stuff on it) Sodas, juice, formula and water are very bad for amplifiers.
emoboywyl on 07/18/2006 00:46:36
I'll try and describe my deisgn concept for the rear cargo area as best I can.
I'm going to cut a piece of 1/2" plywood the shape of the entire cargo area, and permanently bolt it to the frame of the truck. I'll run 2x4's around the perimiter on end for a frame. I'm going to build three seperate partitions, two side by side in the front, and one running along the back. I'll mount the amp in the right front partition and bolt it to the plywood with security bolts. (The left partition I'm going to leave empty in case I ever decide to upgrade and add a second amp) The back partition I'm going to use as a heat transfer and air exchange area, by mounting fans blowing into and away from the amp. I'm also looking at running conduit from my a/c vent line into that area. (I live in phoenix, and the heat here is very bad for amplifiers as well)
On top of all this I'll lay a piece of 1/4" plywood with a section cut out directly above the amp. Then I'm going to strech some grey silt mesh fabric over the top of it that matches the color of the interior upholstry. The windows are already slightly tinted, and if I do this right you wouldn't even be able to tell that there's anything but empty cargo space there when you're looking into it from outside. But the mesh top and the air exchange will allow the amp to keep nice and cool (or at least as cool as can be expected).
Wow, that was a lot. Now about the box. If I give you the space I have to work with, can you give me the design measurements for the box?
I'm going to remove the vinyl/plastic paneling on the left side of the cargo area and build the box up against the frame of the car (well dynamatted) and again paint it and cover it in grey mesh, so again it'll look like part of the car.
The spacial diamentions for the box that I have availible are as such... tell me if this is workable for .65.
14.5"w x 13.5"h x 6"d
I can play with the depth a little bit, but not a lot. Can you first tell me if this is workable, and if so, can you give me the design specs for the box.
I'm planning on spending between $250-300 for the amp, although I'd be happy going with less. I'm really not that concerned with the best quality right now, I'd like something decent, but it doesn't have to be great. I already have great speakers in the front, I really like that sub, but I have no idea what amp to get.
Ok, I'm done, you can breathe now. =)
Thanks for your time, opinions and advice in advance.
Wyl
lilschtive on 07/18/2006 01:18:54
Would a 250/1 JL audio amp work for this system?
(( http://cgi.ebay.com/JL-Audio-250-1-Monoblock-SUB-AMP-NEW-2006-SLASH-SERIES_W0QQitemZ300007556474QQihZ020QQcategoryZ79827QQrdZ1QQcmdZViewItem#ebayphotohosting))
250 W RMS @ 1.5W-4W ??
emoboywyl on 07/18/2006 02:08:33
Now, I really like the slash series amps, but I'm not even considering using a seperate sub amp for a while at least...
but thank you
Plus, what's with all the negative feedback on that seller?
swez on 07/18/2006 10:03:34
Have read about others using a false flooring plan for small SUV's and such. It's a workable plan, if you can keep the amp(s) cool enough.
Some take it one step further and integrate their sub enclosure into such designs. If this makes sense to you, the best location is generally behind the rear seat. You can aim the sub toward the tailgate, make it fire up toward the roof or even down-firing, so the sub is completely hidden from view. (this method is very stealthy)
The sub dimensions noted above, net out to 0.45 cf internally, assuming 5/8" wood thickness. That might be usable for an 8" sub, but few 10's can do well in that size enclosure. (loss of deep bass performance)
14.5"w x 13.5"h x 6"d = 1175 in^3/1728 = 0.68 ft^3 (external)
The internal dimensions calculate out to a net 0.45 ft^3.
The JL 8W0-4 is an option here. The internal airspace volume needed for this sub is a mere 0.375 ft^3. Power handling is also 125 watts RMS and you'll get most of the lower octave of bass here. This is a 4 ohm SVC sub as well.
http://mobile.jlaudio.com/pdfs/9183.pdf
As for amping your front speakers, (MBQ's) and a single sub, the JL 300/4 is a very good option. This nets a solid 75 watts RMS x 2 from the front channels and 150 watts RMS from the rear channels when bridged MONO for the sub.
http://mobile.jlaudio.com/products_amps.php?amp_id=254
Comments?
Swez
emoboywyl on 07/18/2006 13:30:31
How about, keeping the hight and width constant, what would the depth of the box have to be to achieve .65cf? Going off the formula you typed, if I expanded the depth of the box to 8" that should achieve the desired amount of airspace, correct?
I really like the 300/4, but that's kinda at the very high end of my budget spectrum... what else is there that would do a good job, but not totally break the bank?
Ash on 07/18/2006 19:50:10
Don't mean to shake things up here but, if your going for SQ, you need to be aware of a few things.
1. If your going to use a low power sub, then you need to make
sure it will match the transfer function/cabin gain of the vehicle.
This will take place when choosing a proper F3 cutoff (hertz at
-3 db). If it picks up around 60hz, believe it or not a 65-80hz
cutoff would work good factoring in a lo-pass crossover @
80hz and under. Too low a F3, and you get exaggerated bottom
end.
2. For SQ, in order to get a "smooth" low frequency range and
proper blend with front speakers, a rather low Qtc around .707
or less should be used. This will help attenuate upper bass
and keep from drawing from "up front bass".
This being said it is quite easy for the wrong sub to be used. With your internals being around .45cft, I would suggest finding a sub that will meet the low QTC requirement in that available space. Else, you could end up with a sub that is overly robust and hard to tame. At the same time you won't be wasting precious limited power trying to produce lower frequencies.
swez on 07/18/2006 20:09:43
Good point there Ash and you have a lot more experience with transfer function and resonance properties then most guys here do.
Here's the T/S specs of the JL 8W0-4. Care to run them through WinISD for some basic plots? This is a medium size SUV type vehicle. So, transfer function will definitely be a factor below about 55 Hz.
Am thinking JL often specs a Qtc >0.7 for their subs. But, I'd like your read on this one as well. One of these days, I'll get my butt in gear and learn how to use WinISD. Which version is best out there now?
http://mobile.jlaudio.com/pdfs/9183.pdf
Swez
Ash on 07/18/2006 20:48:51
The Alpha version is more accurate on plots, but is harder to work with. I do like the fact that you can simulate response with inlcuded crossovers. I still like using beta for it is simple and quicker. You just have to guesstimate the other factors.
The JL 8W0-4 is not a bad sub, I just worry about the power handling at lower QTC's. I imagine JL spec'ed this one's 75rms nom @ .707Qtc. 125rms for higher Q's.
It's xmax is also somewhat limited (only 6.8mm) although F3 starts @ 59hz even at Qtc-1.0, which is good. Yet, I think this would be too much a robust/snappy setup just to attain full power handling of 125.
All this coupled with a 85db sensitivity makes for a sub in need for a pair to work good at low Q's in my book. Probably would work better in a compact hatchback or low volumes if standing alone.
swez on 07/18/2006 21:09:17
Thanks for the inputs there Ash! CLAP
I would agree that this would probably be a very punchy sub for the reasons mentioned. That's one reason I thought about a down-firing application here. Facing the sub downward and into a carpeted and/or padded floor, will tend to absorb some of the snappy/punchiness of a smaller cone design. Oddly enough, thick carpets/padding will tend to absorb upper bass hot spots and make the sub sounb more smooth in the 60-100 Hz., range.
Try this one out and see for yourself. A nice woolen blankie placed in front of the sub cone, really attenuates upper bass and mids. A few layers of material do a pretty good job. Yes, it may seem hoakie and red-necked to some... but it actually works out well.
Swez
emoboywyl on 07/19/2006 01:49:45
Wow, that's awesome... I can draw a rudimentary design of what I'm trying to do with it, how can I post that or send it?
Which the dimensions and ideas in mind, I can work on how to best place the sub, so it's operating most efficiently, sounds the best, and is well concealed.
Also, I'm not dead set on this sub. I don't own it yet or anything, it was just a previous suggestion. Is there one that would work better for my applications? The 8" maybe? Or maybe just something different.
My problem with mounting the sub so that it's downfiring is still going to be space. Once you see the layout, you'd understand what I mean...
You guys are really helpful, thank you. I have so many ideas running through my head, it's hard to know what's practical and what would acctually work in the real world.
swez on 07/19/2006 06:33:46
A little wild brainstorming is always a good place to start a new project. After all the ideas are on the table, some will step out as highly workable. Others will prove too far out of the box and not worth pursuing. Avoid getting stuck on impractical options that draw your needed focus away from reaching the intended goal.
Many of our guys post pictures on photobucket or similar free sites. If you have sketches and drawings to share, use a format that is easily opened and viewed by those trying to help out. MS Paint is fair for such things.
Have used Power Point for many detailed drawings and sketches. It does a very good job with diagrams, text and other sketch related tasks. All one needs is a Power Point reader or have it as parts of the MS bundled software we often get with a computer OS like Win XP. Those files are best shared via direct e-mails.
There are plenty of 8" subs out there to consider. Just have to balance power handling, enclosure space needs, cost and low bass performance characteristics. A 0.35 - 0.5 ft^3 enclosure is very compact, but when we factor in the board thickness and box constuction, realize the exterior dimensions are about 20-30% larger than internal airspace required by the sub. The more we can hide that box in the sub-flooring, the less protrusion we'll see.
A few words about down-firing sub designs:
1. They work well when designed/integrated properly
2. We get a very stealthy install
3. The angle of the sub in relation to the floor, matters a lot
4. Need an enclosure to give the sub adequate airspace
Comments?
Swez
Ash on 07/19/2006 20:59:05
One suggestion that would also be worth considering is this:
http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=295-550&ctab=10#Tabs
Check out it's recommended box that would fit well into the space you want:
http://www.partsexpress.com/pdf/295-550%20sealed.pdf
The F3 is a little on the high side but this does not present a problem when crossover and transfer function is factored in. Sensitivity is decent (around 89db @1w/1m) and will make good use of a 4 channel amp system.
I recently installed one in my niece's Sebring. Located in the rear corner facing toward the opposite side of the trunk; the sub was very out of the way with tunable results. Low end was not lacking by far, though driven by a weakling overated Sony Xplod 800 4 channel.
swez on 07/19/2006 23:13:00
That sub may be a very good option for you embo. The enclosure size is certainly compact enough and you can manipulate the H,W & D dimensions as needed too.
The price is very good for a woofer of this calibur and the compact enclosure needs are a very good fit too. You can easily come up with an 4,5 or 6 channel amp to power everything as needed and not be a huge current drain on the electrical system either.
Swez
emoboywyl on 07/20/2006 02:49:07
Wow, thank you for that sketch and specs!
I acctually had so much of a blast doing all of this, and with the other stuff I had installed in my car and my mom's car, that after spending the weekend researching car stereo online I drove over to my local shop and convinced them to give me a job.
I know I don't really know much, but the guys there are pretty cool and they're more than welcome to show me everything and let me try to figure stuff out on my own, which is great!
I think all of these "wild brainstormings" have really piqued a natural interest of mine.
I have a couple of questions for you, because you guys are so incredibly helpful and knowledgeable and because I know you'll be more impartial than the guys that work at the shop.
Since I can get things at cost now, I want to know if the equiptment they sell is worth purchasing, since it's so cheap. Unfortunatly, it's quite a limited variety of brands. Here's the amp I was thinking about buying:
http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=15526
I think I'd pay about $105 out the door for that.
And the sub, I'd pay about $25:
http://www.crutchfield.com/S-fspTHx6YWoV/cgi-bin/prodview.asp?i=607X104SX
Feel free to be totally honest, I'm more interested in buying products that are worth my money, rather than total crud, just because it's inexpensive.
I just want to know what's worth buying and what's not.
Ash on 07/20/2006 04:41:19
That amp is a solid one. If you got it, I think you will have it for a long time and be happy with it.
As for the sub. I don't like it. Fs is too high for a 10". Not to mention even though it will fit in a small box, it will be at the cost of smoothness. The small box range for this one is on the high Q side. I'm taking that this is a SPL sub and not a SQ.
emoboywyl on 07/20/2006 10:36:24
Cool, thank you!
I'll pick up the amp today, and forget about the sub.
I'll take a good hard look at that sub you posted my the link for. Like I said, it's not worth spending a few bucks less if it's going to sound like **** in the end.
swez on 07/20/2006 15:43:30
Ditto! Grab the amp, look at the Dayton Quatro sub mentioned earlier. I think you will be very please with that combonation and the front channels are enough to power your MBQ's too.
Yes, the MBQ's like more power, but this is a good start.
Swez
emoboywyl on 07/21/2006 02:32:12
As soon as I get the money together I'd really like to buy a JL 450/4
Then as I do other related work on the car, I want a JL 500/1 seperatly to power the sub, and a pair of MB 6x9 for rear fill.
swez on 07/21/2006 13:44:42
That JL 450/4 has a few interesting features in it. It uses a highly regulated power supply, requires a 60A fuse and nets the following
output values:
4 channels, Stereo mode:
1. Front channels: 150 W RMS x 2 @ 1.5 ohm – 4 ohm (11 – 14.5V)
2. Rear Channels: 75 W RMS x 2 @ 1.5 ohm – 4 ohm (11 – 14.5V)
You can also bridge front or rear channels for powering subs too. Not the most efficient way to use this amp, but it will work if you wish to do that.
Note the rear channels have 50% less RMS power than the front channels do, on this amp. No need to go and spend big money on high end rear speakers either. A solid pair of 2-way Coaxials will do the job here. Put your best speakers up front as this is where you'll get the biggest bang for your buck.
The 500/1 is a very strong sub amp. It is very efficient with input power as it's a Class D MONO amp. This amp should be fused at 50A's. So, when you add everything up, these amps will need a minimum of #4 gage wiring from the BAT to a Distribution Block. Then, you can use #8 gage wires to each amp and #8 grounds too.
If you're running longer than 12 feet of #4 power wire on this truck, drop to #2 gage main wire and use #4 or #8 wire to feed your amps off the D-block. Use a fused D-block as these amps do not have internal/external fuses.
FYI: To conserve on power consumption from the amps, consider the JL 300/4 as an option. It delivers 75 watts RMS x 4 and if you use fairly efficient speakers, that is plenty of power to gain high SPL and very good clarity too. This amp only needs a 40A fuse and you can still use the 500/1, but stay with #4 power feeds and # 8 wires for each amp.
This option will provide plenty of clean power and save you the added costs of a larger amp, bigger wires and easier on your electrical system as well/
Comments?
Swez
emoboywyl on 07/22/2006 02:09:21
I've got the MB Quart QSD 216's in the front.
I'm not really all that interested in the rear speakers, since it's just my daughter back there, and with the placement of the quarts I don't really hear any difference when they're on.
So, what do you think about Soundstream bringing back the little blue reference series amps? The old ones are incredible, I wonder about the new ones... will they be as good?
If so, I might just wait till we get some at our shop and buy me one of the 800.2 for my Quarts and a 400.1 for the sub.
What do you think?
emoboywyl on 07/22/2006 03:01:10
Also, since I'd just be using the 500/1 paired with the 10wv2-8 DVC I think/hope. I'd wire that in series to 4ohm. Or the 10" Dayton at 4ohm.
I'm really just using the sub for balance, rather than punch. I don't want to hear the base over the rest of the music, but rather have it even and balanced so the music is as clear and vibrant as possible.
So I guess the question here is, is the 500/1 excessive? I know the Quarts love power, and I'm more than happy to feed them that, but would the 250/1 be sufficient, or would it really be worth it to go with double the power?
This question also in relation to the previous one about the Soundstream amps... I'd like to know your opinions about this setup and those amps.
swez on 07/22/2006 09:15:51
As for bass, the 250/1 has plenty of power to bump when you want it, but will not knock the baby out of his/her car seat either. SMILE This amp will deliver about 3dB less power (SPL) to a sub than its bigger brethren. (JL 500/1) Less current is needed too. A single sub that can manage 250-300 watts RMS and has a coil impedence between 1.5 - 4.0 ohm is fine. It does not have to be a pricey JL sub either. There are many fine subs out there that fit this need for under $150.00.
If only powering the MBQ's and no rear speakers, the JL 300/2 is a very good choice. Plenty of RMS power for clean mids/highs and adequate midbass too.
About SoundStream products... they were once considered a top tier brand name and had the prices to match. They changed hands about 4-5 years ago and have now expanded from the older premium lines, to several very affordable new products as well.
I'd love to get my hands on a few of the new products and test them out just to see how they stack up with other great brands we now see out there. The older amps and such, (Circa 2000 and older) were pretty much bullet proof and some of the cleanest amps around. The new products are probably still very good. However, they have now gone to a mass-marketing program, added more products and lower prices have put this venerable brand in reach of the average consumer.
How/why did they make that change?
1. Lower cost due to lowered profit margins?
2. Automated assy precesses?
3. Off shore labor?
4. Use cheaper and fewer internal components???
The short answer is... probably still a very good product line to consider for high end "Audiophile" installs. Are they up to par with other amps in the same price range? (probably equal to, or better than most branded names in same price class)
Again, hands on experience with the newer products, would be a definite plus.
Swez
emoboywyl on 07/23/2006 00:54:36
That's kinda what I was expecting...
I'll definatly be able to get my hands on one when they arrive, I'd love to play around with it some and check out how it sounds. The great part is that I'll be able to do that on someone else's car before I go and spend the money on one.
This really is a fun industry to work in, albeit a very dirty one. It's like I'm getting paid to work on a hobby! =)
swez on 07/24/2006 10:32:40
If you are young, small in frame and can climb around inside tight spaces for hours at a time, this is a very good job. Big guys have a much harder time doing this kind of work.
Know what ya mean about turning a hobby into a money maker. If we love what we do and get paid to do it, it doesn't get much better than that.
Keep up the good work and learn as much as you can,
Swez SMILE
emoboywyl on 07/24/2006 14:06:04
well, not too small in frame, but I make do! =)
I'm workin hard, although that doesn't seem the norm for the shop I work at!
I want to learn as much as I can, that's why I keep asking, and sharing my newfound knowledge here. as well! Thanks for all the insight!
Wyl
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