Hi everyone, I am new to this forum and car audio. I have currently build and installed a "decent" system by my terms. (with my budget also) I currently have one 12 inch SVC audiobahn sub rated at 500 watts RMS, hooked up to a sony 400 RMS amp(no laughing), and by all means, for my taste it sounds fine. After having this system for awhile, I have decided I want to move up in the sub department. I am thinking of going with 2 decend DVC audiobahn 12's, or rockford punches. I do not know a lot about different subs, just what I read any hear.( any sugestions by all means, however on a low budget) Now regarless of the subs, I am confused on the amp situation with DVC subs. I have looked at many wiring diagrams, and I am ok with the wiring, but its matching the amp. I have seen a lot of people go with 2 channel stereo amps, and either bridge them, or wiring it so there one sub per channel. I would perfer to wire both to one channel. Now if you bridge a 2 channel stereo amp, does it not make that channel mono? So why not just go with a mono block amp? Say the subs are wired together for a 2 ohm load at say 800 watts total RMS.(just making stuff up here) Why go with stereo bridgable able to 800 watts RMS at 2 ohms, or a mono amp that will do the same. I have always read it is better to only power one sub with a bridged amp. I must be missing something. Also what do most think about how closely the amp shoud match the subs in the RMS department? My one friend who has a kickin system says that you cant get too close to the RMS of the subs or they will blow? Or is he the one blowing smoke? Thanks for any imput.
Replies (50)
Swez on 12/17/2003 22:41:32
Good questions..
1. MONO vs Stereo amps.... it's a preference and up to the user to determine the best fit for his subs and amp. In most cases, a 2 channel amp is bridgable for more output to the sub(s). But, most 2 channel amps require a 4 ohm net load to remain cool and stable in bridged mode. (unless you buy a High Current [HC] model) These will take low ohmic loads,in bridged mode, very clean sounding, but real current hogs too.
Also, most 2 channel mosfet amps are commonly Class A/B amps. They are clean sounding, but have low efficiency numbers (50-60% eff.) in terms of watts consumed VS watts they can put out. That means a 200 watt amp (output) will consume close to 400 watts of power. The rest is lost to heat and other inefficiencies.
MONO Class D amps are a good match for subs. They can take lower ohmic loads, draw less power for high output and are generally very efficient. (80-90% eff.) They tend to be cheaper to buy as they have less circuits in same and offer more output power then similar rated A/B amps. The down side... Class D is dirtier and has higher distortion values. In sub applications, no problem... you cannot detect this distortion level until in excess of ~10%. This is a sub amp only... not designed for mids/highs!
2. Many serious bassers do go MONO block on subs. Class D is good for most bang for your buck. Just make sure you know what ohmic loads they can take and the RMS output at a given load. The other part to consider... how much curent will the amp draw VS how much power is available from the electrical system (ALT/BAT) to draw from.
If you have the 3800 series engine, most likely the ALT is a 108A model and your BAT is probably stock rated at ~600 CCA (Cold Cranking Amperes) This stock setup (in good health) can support an amp that draws about 80 amperes of current. That translates to an amp that can put out 600 -1000 watts RMS, depending on the Class of amp used. If you want more thump... plan on some electrical upgrades in the near term.
3. Bridging a 2 channel amp and only use one sub applies to Class A/B amps that need a 4 ohm load for max power transfer. If you have an SVC, 4 ohm sub... this is true. However, if you have DVC's, you can still bridge the amp to MONO and configure the subs so that you get a 4 ohm net load. Usually, a 4+4 DVC setup is needed and wired in series/parallel will net the magic 4 ohms. One can also use a pair of 8 ohm SVC's (wired in parallel) to obtain same results.
Say more about your budget on this pending upgrade. If you like the Bahn sub you have now, can easily get a 2nd one to match and upgrade the Sony amp to something more suitable... a Class D MONO amp makes sense here.
More details to share later, after the budget numbers are established.
Swez
Joepro on 12/18/2003 15:01:23
I have about 285$ saved now in the "sub fund", but after next paycheck and any gift returns and money from christmas will boost my funding. I am hoping to have about 500 to spend on ebay for this. ( where i got my current setup) I will probably buy either the subs or amp before christmas and the other after. I definatly want to get class d amp, but i found something else confusing. I was looking at the audiobahn subs on ebay, and it said they were pre wired for 2 ohm stereo operation. Does that mean i can not use a mono amp with them? anyway thanks for the great reply.
On the engine info, they did not put 3800s in granprix back then, it was the multiport 2.8 or 3.1, i got the 2.8, but it is a better aftermarket alternator. ( went through 2 stock ones, GM altenators are junk) I also have a 1000 watt RMS capactior.
alanjlamore on 12/18/2003 17:44:30
I always thought that getting DVC subs was only worth it if you're going to have 3 or more subs hooked up. The Dual voice coils only allow for more wiring options IMO.
You can usually get the same type of subs (same RMS values and brand) with one voice coil or two, depending on your wiring needs.
This is how I understand it anyway. If you're only going to have 2 subs, then I'd think that getting a MONO amp and wiring the subs in parallel would be the way to go, as long as the amp can take a 2 ohm load (assuming that the subs are each 4 ohms).
I've always been confused with DVC subs too because the numbers get a little crazy when wiring them different ways. A friend of mine had 2 great DVC subs (forgot what brand), but had them wired to only use one voice coil each. His brother saw this and rewired them and now my chest and nostrals vibrate when I sit in his car.
Oh yea, I've always been taught that you should match your watts RMS that all of your subs can handle with the same watts RMS that the amp can put out. If you go by max, then you're not getting accurate numbers since max says what the sub can take, or what the amp can deliver for a very short burst durring one note of music. I'd think that if the RMS values match and the amp's highest max output isn't much more than what the subs can take, you won't have to worry about blowing any subs.
Just my oppinion, hope this helpes,
cplkittle on 12/18/2003 19:10:00
Matching RMS as close as possible for the amp/sub(s) is the standard by which most people go by. I usually go a little larger on the amp when I can. (ie. 2x400w-RMS subs = 1000w amp-RMS). In my opinion this is better because you aren't using 100% of your amplifier's available power at full throttle. Just keep your gain and bass adjustments in check to prevent damage to your speakers.
Joepro on 12/18/2003 23:07:36
The only reason I said DVC's is because they are everywhere on ebay. I have seen that most companys do have the same subs in single voice coils. Perhaps that is they way to go if the price is right. Any amp reccomendations, there are many cheaper amps on ebay, but what they output and their prices scare me, heck my sony amp cost more. I was on another car audio forum and the guys there really spoke highly of JBL amps for best bang for your buck.
Swez on 12/19/2003 09:45:36
Definitely... the JBL Power series MONO amps are potent, reliable and very well priced. Nothing cheap about them and they do deliver more than rated power at 1 & 2 ohm loads. The only think lacking in the JBL Power series, is a subsonic filter. If you use a sealed enclosure, no need for this feature. But if you go ported or BP, them $30.00 will get you a pair of inline SS filter plugins.
A pair of 4 ohm SVC subs will net 8 or 2 ohm loads to the amp, depending on how they are wired. (series or parallel) DVC's come in so many flavors these days, the options are many. But if you like the sub you have now and just want to have more bass, a 2nd matching sub and a more potent amp will give very good results.
No need to dump all you have now and lose all that investment and install work. Can still use that Sony amp for Mid/highs if not a Class D amp... (2 channels are not Class D) and get a larger Class D amp (JBL 600.1 or 1200.1) to power 2 subs. These draw 57/114 amperes of curent respectively at full power. However, under average listening conditions, more like 30/60A., of draw as these are very efficient amps.
Power management may become an real issue if you have a small ALT/BAT now. The CAP mentioned may help keep your lights from dimming to much on large bass hits. But if you add more amping power... make sure your electricals can handle same.
Swez
Joepro on 12/19/2003 23:37:24
So heres what I found. The jbl 600.1 power amp falls right into my price range. At 600 rms at 2 ohms, i was looking at the rockford subs listed on ebay. For the ones that can be wired at 2 ohms in my price range, have a combined rms of 800 watts. Is this too big of an rms gap? For the regular listen, me, will I notice the gap? Assuming I go with that amp, any sub sugesstions?
500$-200$(amp)
300$ for subs and box
cplkittle on 12/20/2003 11:20:41
I believe that the JBL will push the fosgates pretty well. The one thing you have to pay attention to is distortion. Not enough watts is worse than too many watts. If your speakers sound bad or bottom out, or have more of a buzz sounding bass instead of a clean warm sound you could damage the speakers. If you are getting good sound and it dosen't look like the speakers are moving much, you are good. High quality speakers will produce alot of sound with very little visible movement.
Also it depends on the type of box they are in. Generally ported boxes will require right at rms-rms to sound good, sealed boxes will usually give you good sound at +or- up to 100w of the rms.
uochronos on 12/20/2003 23:44:46
If your looking on ebay you can get 2 10" alpine type R subs for 200$ + around 30$ shipping and those would match to that amp perfect these speakers are 300watts rms.. i'm running 2 of them on a 500 watt phoenix gold amp and they sound amazing. if you don like 10's you can get 2 12's for like 30$ more i think it was. same RMS
Joepro on 12/21/2003 02:20:23
Its ironic you mention Alpine r's. i was just looking at them a few hours ago, they sont look too bad. I have alpine 4x6s and im happy with the quality, so i beleive they subs would be good quality too.
Swez on 12/21/2003 07:29:57
There are many subs out there that will sound great at 300+ RMS/ea.
The RF subs are fine... if you are willing to pay a premium for that RF LOGO. Not that RF is a bad product.... just not a good price unless you shop them hard.
You mentioned a 4 ohm SVC Bahn sub earlier. Do you like it enough to buy a 2nd one? If not, Infinity, Alpine, Adire and many others will do a fine job at 600+ watts RMS. The Bahn is a good SPL sub while the others are more SQL in design. You'll get more SPL with a modest amp and Bahn subs as these have very high efficiency ratings. (Ie: requires less watts input, to drive up the dB's)
BTW: RMS matching of the amp VS the subs is very important in Competition rigs. However, in a daily driver it's fine to use subs that are rated higher than the amp. Will work fine as long as one does not push the amp well into clipping and excess distortion.
There are good arguments for going both ways on this topic, but the best way to gage this for most, is with their ears. If the subs are loud but sound strained or un-natural, you may be clipping the amp. That is not good for any speaker... no matter the wattage ratings.
The best way to tell if your speakers are getting clipped signals... get out of the car, open the doors, crack the trunk/hatch and listen from say 10 feet back. If the mids and highs sound shrill or harsh... they are clipping. If the bass is muddy, middy, lacking definition etc., amp may be clipping here too... or a poorly matched enclosure.
Swez
Joepro on 12/21/2003 10:53:09
The bahn sub i have is not bad imo, but it is a lower end sub for the bahn line. (this does not bother me...) The reason I am trashing the idea is that I have people at school offering to buy my old setup, so then I can just get a new one. I got that bahn sub for 40 bucks on ebay brand new believe it or not, and at 500 watts rms, it might not be a bad idea to get 2.....I can not tell the diffrence that it is a lower end sub, or it might be that I dont care, Its bass, its there, and I can hear it, thats my style. I have noticed the rockfords are very expensive, and I might just shop something cheaper, because I do not buy for brand. As for clipping I do not know alot about it, is that when you underpower your speaker?
So if I get the 2 bahn subs, that would be 80 bucks for 1000 watts rms. Id probably would have to move up in power from the jbl amp, 600 rms is most likely way too low for those ones. I really did not see any other SVC subs from bahn with a lower rms. I am gonna shop this hard, so its back to the drawing board for me.
Joepro on 12/21/2003 12:03:02
Ok heres what I have found thus far. Audiobahn is the cheaps(well who didnt know that)
Audiobahn aw121t flame excusion, about 170 shipped for a pair 1100 wats RMS
Audiobahn abpt12t 2 12 audiobahns in bandpass box, 170 shipped 800 watts rms.
2 infinity 120.3se 180 shipped 600 watts rms
these are just a few, any more sugesstions?
Swez on 12/21/2003 13:48:56
Hummm, here's a thought... does your car have a gas pedal? Sure right? Do you always drive it... "pedal to the metal" ? No... not quite huh? Why not? The car may not do well in the long run and run the risk of frying the engine right?
OK, same deal with subs and audio gear in general. We don't crank up our systems to the max all day long. If we did... we get a noise pollution ticket. Run audio gear too hard and sooner or later, something has to give.
And oh... do we listen to our TV set all the way up too? The speakers and amps in a common TV set are only a few watts per speaker. If we turn it up too high, sound will distort and the neighbors will probably complain too. (or Dad will come in and stomp the set to pieces)
OK, if you did get a 2nd Bahn sub (great prices BTW) and used a JBL 600.1, that'd be a very good match for SPL sub applications in the budget range you mentioned. If you shoot for a larger amp to power these subs... can do... but the price of the amp went up and so will power consumption from the electrical system.... (MORE MONEY INTO THE PROJECT THAT WAS NOT IN YOUR BUDGET)
Finally, if you went from a 600 watt amp to a 1000 watt amp for a pair of these subs, can expect (~+2.4?) more dB of SPL from the larger amp. However, current draws will go up nominally from ~45A. (JBL 600.1) to more than 80A., with a 1000 watt amp... if not more, depending on the style of amp used. Question is... is all that expense worth a few more dB of bass SPL? To some, it might not be worth the effort and expense. But to a SPL Comps guy... yes!!! Every fractional dB increase he can get is worth the effort and cost.
Does this make any more sense to you now? Comments
Swez
cplkittle on 12/21/2003 20:26:52
I would recommend the infinity, and would HIGHLY recommend building your own box.
Prefab boxes are good for.. well firewood in my opinion. For an 88 grand prix, I would go with sealed or ported. I had an 89 sunbird, and a bandpass (barely fit in the trunk) did not sound good. Every frequency sound the same, just a monotone boom boom boom, and frequency drops were converted to volume drops. and I was told q-logic boxes were good. come to find out that I was short almost 1cubic foot airspace on the sealed side, and .75 too much on the ported side, and with 3 3" dia ports, it was tuned to something like 600Hz.
changed to a sealed box, and was very impressed. I was running JBL 12's at the time.
I also have 2 audiobahn aw1251t 12" subs, they are pretty powerful, and don't require much to push them, but they are not very clean.
Everyone will tell you that it is better to spend a little more now than alot more later. You can spend 200 now and another 300 later when you decide to upgrade, and have a $200 pair of speakers laying around, or spend that extra 100 now and not have to worry for awhile.
Joepro on 12/22/2003 22:40:05
One more question, I found a set of subs with a box and it says its pre-wired for 2 ohm stereo operation. Would that mean I cannot use a mono channel amp?
Swez on 12/23/2003 06:37:21
Depends on the subs you mentioned and the amp you intend to use on them. The JBL Power series will do 1 and 2 ohm loads with same power output... (600 + RMS). There are other monoblock amps out there that will do 1 ohm, but most are rated for a 2 ohm min load.
What subs are you talking about here? We can review the specs and make some suggestions that may work if you choose to go this route.
Swez
PS Joe, you seem to be waffling about what to do next? It would be most helpful to start at the end goal and work your way back in gear choices. Please, don't get all caught up in "what about these" or how about that" . Figure out what your end goal is and a budget to work with. Once you have the end results (target) well planted in your mind, the rest will drop into place with some help from the team here.
If you are just exploring options, read the posts from others that have been down this road already. This will give you a better idea of what you are shooting for. Once you have that plan firmly planted in your mind, then we can be very effective in leading you to a successful outcome. Try not to get bogged down in the specs that are not clear or mystify you. We can help you understand them as you go... but specs are not the entire picture... the results are.
Joepro on 12/23/2003 09:11:56
I was looking at the audiobahns I found for 155 bucks. It says they are prewired for 2 ohm stereo operation. If I can hook them up to the JBL amp thats the way I was going to go. After I read 2 ohm stereo operation, I know the JBL amp is mono. I am close to my decision, really what ever I can hook up to that JBL amp in that RMS range.
From my research the audiobahns that cplkittle were the same way with 2 ohm stereo operation.
Swez on 12/23/2003 11:07:03
QUOTE: "I was looking at the audiobahns I found for 155 bucks. It says they are prewired for 2 ohm stereo operation." Tells me nothing useful w/o product details or a web link...
Which subs are we taliking about here? Bahn makes about 9 Zillion subs with different part numbers and specs. The product number helps us to look at the sub package and then we can advise you if that product will fit the amp you are considering. Sorry... I left my mind-reading program at home today... hehe
Play ball with me Joe and respond to the questions as we ask for very good reasons OK?
Swez
PS Maybe it's just me, but am feeling like we're not on the same page here Joe... we can get you to ground zero & soon, but we need good feedback on vendor brands and part numbers you are referencing. We can get the details from that and advise if a good fit or not. Better communication here PLEASE !
Joepro on 12/23/2003 11:40:29
All these bahn subs say stereo operation: (that are in my price range)
Abp12t 800 watts RMS SVC(box and all, put together by audiobahn, so space should be right)
aw1251t DVC subs, pre wired for 2 ohm stereo operation. 800 watts RMS
Aw121t SVC 1000 Watts RMS. Stereo operation.
I think were not on the same page because All I wanted to know was if you can hook up stereo subs to a mono amp. If this is the case, I am buying 2 of the above subs with the jbl amp.
Cheers :)
cplkittle on 12/23/2003 11:42:18
the aw1251t audiobahn 12" subs are 4ohm DVC, 400w max.
Do you have a link to this page on ebay? I am not familiar with audiobahn prewiring their subs, be careful not to buy something advertised as new when it may not be. Mine came in a factory sealed box, no prewiring.... Just looking out for you.
erikcooper on 12/23/2003 14:49:10
I am not an expert and not giving any advice, only asking this question in case it may be of importance. I planned to buy audiobahn subs for awhile but when I was at a vendor's shop he told me that while audiobahn was good, they rate their RMS at twice what it truely is. Is this true? He said that if I took say an audiobahn 1000w RMS sub and hooked up say a Fosgate 1000w RMs amp that the Fosgate would blow, while and Audiobahn amp rated the same would not... Comments?
cplkittle on 12/23/2003 19:45:45
did that vendor sell audiobahn products?
Joepro on 12/23/2003 23:11:01
I dont know that audiobahn pre-wired it, I believe it was the vendor, heres link. This is just one, many are selling this combo. Also have links to others. ( I dont know how to do links ill just post the urls)
aw1251t
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3066219052&category=48613
AW1251T
12” NATURAL SOUND WOOFER
45 oz. Strontium Magnet
Power Handling: 400 watts R.M.S.
Frequency Response: 24Hz - 1kHz
Efficiency: 92.1 dB
PHAT Foam Surround
Non- Pressed, Non-Transfer Paper Cone
KM3’ Coated for Virtually No Cone Distortion
2” 4-Layer ASV Voice Coil
Dual 4 Ohm
2 Ohm or 8 Ohm Operation
Mounting Dimensions: Depth; 5 1/4” Hole; 10 7/8” Diameter; 12 1/2”
Lug Lock Terminals
Abp12t
This is from audionbahn, box and subs.
ABP121T
SINGLE 12” TUNED BANDPASS SYSTEM
High Quality MDF Construction
Black Suppleleather Covering
3/8” Plexiglass Window
Blue Interior Neon Lighting
Mirrored Interior Panels
Single 12” PHAT 2” Foam Surround, Non-Pressed KM3(tm) Coated Cone Subwoofers
50 oz. Strontium Magnet
2” 4 Layer ASV Voice Coil
Bumped Back Plate
Extended & Vented Pole Piece
Gold Binding Post Terminals
Power Handling: 400 Watts RMS
Sensitivity: 101dB
Frequency Response: 28Hz - 150Hz
Impedance: 4 Ohm Mono
Dimensions: 15”(H) x 19.5”(W) x 15”(D)
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3067180901&category=32823
This is just one of many also selling this setup
ABP220T
DUAL 12” TUNED BANDPASS SYSTEM
High Quality MDF Construction
Spun Aluminum Venturi Ports
Black Suppleather Covering
3/8” Plexiglass Window
Blue Interior Neon Lighting
Mirrored Interior Panels
Dual 12” Molded, Texture Injected Poly Cone 45 oz. Strontium Magnet
2” 4 Layer ASV Voice Coil
Bumped Back Plate
Extended & Vented Pole Piece
Gold Binding Post Terminals
Power Handling: 800 Watts RMS
Sensitivity: 105dB
Frequency Response: 25Hz - 150Hz
Impedance: 4 Ohm Stereo
Dimensions:
16.5”(H) x 29.5”(W) x 15.75”(D)
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3067154644&category=50567
I would like to go wtih the bahns because of price. I am young enough that I do not need that clean bass sound.
Here is my final plan:
One of those setups, with JBL amp if possible, if not, another amp.
The only thing that consfuses me is how that box is wired to 2 ohms.
erikcooper on 12/24/2003 01:37:16
Yes cplkittle the vendor sold audiobahn products. He was telling me that they are good but not to be dissapointed when I found that out...
cplkittle on 12/24/2003 10:39:27
I double checked my aw1251t subs, they are listed as 400w RMS, which surprised me for some reason I was thinking they were 400w peak. In light of my error, I have been thinking, and you may be right, Erik. I am pushing 2 of these so called 400w RMS subs with a 600w peak kenwood amp. I have it bridged, so I might be pushing 300-325 RMS from the amp-divided by two= 150 watts to each audiobahn. Now, I don't know if either these are bad ass speakers because they sound really good in the bandpass box I built for them, or if they really do double the RMS and I am close to matching it. I have never pushed them to the point of distortion or clipping.... never needed to, they are pretty loud as they are. I will do some research on this...
erikcooper on 12/24/2003 11:47:35
Please let me know what you find out in the research.
Joepro on 12/25/2003 09:45:54
I dont know a lot about car audio, but I have picked up this little bit of info from the local shop. Audiobahn only rates their subs in RMS, never in peak. I do even know if they know the peak. Peak pretty much useless anyway, so thats why audiobahn said heck with it. (this is what I am told)
Joepro on 12/26/2003 23:25:54
"The only think lacking in the JBL Power series, is a subsonic filter. If you use a sealed enclosure, no need for this feature. But if you go ported or BP, them $30.00 will get you a pair of inline SS filter plugins."
Could someone shed some light on the SS filter? Im going JBL amp with BP, so I dont know a lot about this filter I need.
uochronos on 12/26/2003 23:46:37
well a subsonic filter usualy filters out everything below 20hrz mainly because you cant hear it much below that and to keep the sub from over excursuion. in a band pass or ported box you need to have a filter that matchs the frequency that your box is tuned to... for instance if your box was tuned to 30hz and at 30hz its excursion was 15mm and at lets say 15hz it would have an excursion of 25mm(these are totaly made up numbers) and lets say its maximum excursion is 20mm well in that case you wont want your speaker to ever hit 15 hz and 25mm because that would be 5mm past maximum excursion which very likly would damage the speaker. i hope this helps its not really all the details but its the way it works in simple terms
Joepro on 12/27/2003 16:29:25
I can not find them anywhere, are they really just inline crossovers? Where can I find a set of these?
compvr15s on 12/27/2003 16:41:27
http://thezeb.com/caraudio/harrision_labs.html
Joepro on 12/29/2003 11:42:45
As you all know Im on a tight budget, would you hesitate to buy this? Or should I fork it out and get a new one?(not that much more)
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3068013645&category=18797
cplkittle on 12/29/2003 19:44:43
First of all, have you decided on the subs you want yet? and what are their RMS watts?
I almost bought one just looking at it until I saw this line in the description:
FACTORY RECONDITIONED - TO NEW SPECS
I would definitely email this guy and ask him a few questions first.
1) who is offering the warranty (some companies don't do online warranties)
2) what are the new specs, and what were the old specs?
3) can I get a picture of the actual amp itself.
These are good amps, just be weary of reconditioned or refurbished items.
another thing:
NOTE: These are expected to arrive on November 10 th and will start shipping then.
how long has he been trying to auction these?
Joepro on 01/6/2004 17:33:30
Got the Jbl amp and the audiobahn box with the SVC subs. The JBL amp has 2 sets of speaker terminals, so can I just run a wire from each negative to one on each sub and same for positive for parallel? will that work?
swez on 01/6/2004 20:48:13
One set of terminals to each sub is fine. These terminals are wired parallel internally. As long as you don't go below 1 ohm loading, should be fine.
No need for a SS filter if sealed. The enclosure will naturally roll off subsonic frequencies automatically.
If using a ported box, protect your subs by using a SS filter that is close to ported frequency... Ie ported at ~30 Hz, use a 20 - 30 Hz filter to block all below tuning frequency. If you blow your subs trying to save $30.00, I'd say that would be an expensive mistake we all can live without huh?
Swez
erikcooper on 01/6/2004 22:13:54
Wouldn't you want those 20hz waves? Wouldn't that just be deeper bass? Is it not good to tune them at 20hz or is there somethign I am missing?
Joepro on 01/6/2004 22:14:03
Ya I went to our local car audio store and asked for a SS filter and the guy laughed at me. He said where are you going to find a signal below 20 hz. He did not even sell them....Anyway I walked out went home and ordered a pair from PE.
erikcooper on 01/6/2004 22:36:20
I would love to have some subsonic frequencies coming through my subs so that I get the vibration but now sound. That would be cool. Probably not good for me but still. So what is the lowest frequency we actually get through our subs?
swez on 01/7/2004 01:15:06
Most folks cannot hear much below about 30 Hz. Below that, we feel it. The reason for SS filtering on a ported box, is that frequencies below the tuned port are very hard on subs. The cones become unstable, these frequencies are not very useful in car audio applications and these subsonic (below what we can hear) really eat up amp power.
In better quality HT applications, we might want to port down to 20 Hz. That's where movies come to life... Volcano, Dante's Peak, Jerassic Park, The Matrix and such....
Swez
Munchiesyumm on 01/7/2004 01:58:42
hey Swez..
I like your movie choices.. SMILE
So cplkittle you think the Bahn's are over rated? Where did you guys read/find this out? I would be interested to know. Maybe we should start a new post on it and have thoughts shared about this topic?
erikcooper on 01/7/2004 02:18:58
I think we decided that they did not overrate munchies. I can;t remember how but there is more discussion in another post.
I would need to tune at that low of frequency then, as I plan to put in a DVD player.
In case anyone was wondering, this is a daily driver, BUT, it will be a show vehicle, once I get that much money invested. Once I learn fiberglass fabrication the interior will be amazing...
cplkittle on 01/7/2004 08:47:27
as far as frequencies below 20 Hz, once the driver reaches the tuned frequency of the box, let's say 30Hz, the excursion is at its lowest. Below the tuned frequency, the excursion increases at a phenominal rate, maxing out at around 7-10Hz below tuned freq, and if it were possible, it would double every octave lower. (one octave down from 30 is 15, one octave down from 15 is 7.5, then 3.75 and so on). so a driver that has an xmax of 12mm would peak at around 22Hz. At 11Hz, the driver will try to reach 24mm, at 5.5Hz, 48mm and so on.
These numbers are not accurate to the 'T'.
Joepro on 01/8/2004 23:04:49
I am amazed already at how much better the JBL amp is that the sony. Its pushing 200 more watts Rms, and does not take as nearly as much voltage out of my electrical system. I haven turned it up really loud,(since the subbies are new), but even in places my voltage meter would just up and down with the sony it does nothing. What a much more efficent amp! I like the subs system too it sound very clean to my ears. Here what I ended up with:
Jbl 600.1 power series amp
Auduibahn abp12t tuned banpass system with 2 12inch SVC subs at 400 RMS each.
Other system components:
Pioneer 550 premier deck
Alpine 4x6's
sony 6x9;s (soon to be replaced now, but I got them for free)
Sounds nice for an entry level system, at least I think so!
I wanted to finnaly say thanks for all the help from everyone on this topic!
Joepro on 01/10/2004 20:34:49
Well, all my hard work with the system has just gone to ****. I totaled my car last night..... (deer) I am going to retrieve my subs and head deck tomorrow. I know the head deck still works because it was the only thing still on after i crawled out of the car. I wasnt there when they filpped it over, but from what I hear the subs and amp are still intact. Im just gonna have to sell it anyway to pay my fine for crossing the center line anyway, but thanks again for helping me out. Maybe someday I will have a car to build a system in again, but thats pretty far off.
swez on 01/10/2004 22:25:33
Oh man, am so sorry to hear that happened to you. Do you know what "Deer Whistles" are? They are inexpensive plastic devices that mount to the bumper of the car. They emit a high pitched noice deer can hear from a goodly distance and supposedly put the deer on the run, back into the woods. I have used them in Deer Country and never had a problem... but that may just be "dumb luck" on my part.
I hope you are OK and you gear can be reteived for another install.
Swez :-(
Munchiesyumm on 01/12/2004 21:04:29
I have a 1989 Pontic Grand Prix my self, they are pretty decent cars. But extremely slow, I never wrecked it but it was my grandma's car and she wrecked it a few times, I sure wouldn't want to get in an actsident with a Grand Prix. How did it hold up? I was always afraid if I hit anything I would been a goner.! Been close to hitting a Deer my self, I sware the breaks only work when you don't need them to.
Mine was 2.8ltr v-6 automatic with 134,000 miles, stock tape player (impossible to remove for less than 250 dollars) 2 door coupe completely faded interior and the paint was in horrible shape. But the engine keeps on chuckin along. It's too bad you got in a wreck.
Try looking into getting a job living with you're parents which I do really gets you money to save up for things. I thought I remembered reading you were in high school.
good luck and hope you get it all worked out
erikcooper on 01/13/2004 00:22:14
I am a sophomore in college (20 yrs. old) and I still live with mom and dad. Why not? They pay for my school and all and most of my money I make is just for me.
Munchiesyumm on 01/13/2004 01:07:19
I am sixteen years old and a I am a Junior in HighSchool. I turn 17 next month Feburary 13th 1987
Joepro on 01/13/2004 12:19:46
Do you know what "Deer Whistles" are?
~I do, and I dont bother with them, my dad see a substantial amount in the body shop hit by deer......
As for the car, I suppose it held up well for what it went through.
impossible to remove for less than 250 dollars
Not in an 88!
Give me a pic of your dash, if its anything like the 88 I can rip it right outta there!
As for me I am a senior in high school, and I have a job. After this It will be a cold day in you know where before they help me buy a car now. Thats just how they are.
Replies (50)
Swez on 12/17/2003 22:41:32
Good questions..
1. MONO vs Stereo amps.... it's a preference and up to the user to determine the best fit for his subs and amp. In most cases, a 2 channel amp is bridgable for more output to the sub(s). But, most 2 channel amps require a 4 ohm net load to remain cool and stable in bridged mode. (unless you buy a High Current [HC] model) These will take low ohmic loads,in bridged mode, very clean sounding, but real current hogs too.
Also, most 2 channel mosfet amps are commonly Class A/B amps. They are clean sounding, but have low efficiency numbers (50-60% eff.) in terms of watts consumed VS watts they can put out. That means a 200 watt amp (output) will consume close to 400 watts of power. The rest is lost to heat and other inefficiencies.
MONO Class D amps are a good match for subs. They can take lower ohmic loads, draw less power for high output and are generally very efficient. (80-90% eff.) They tend to be cheaper to buy as they have less circuits in same and offer more output power then similar rated A/B amps. The down side... Class D is dirtier and has higher distortion values. In sub applications, no problem... you cannot detect this distortion level until in excess of ~10%. This is a sub amp only... not designed for mids/highs!
2. Many serious bassers do go MONO block on subs. Class D is good for most bang for your buck. Just make sure you know what ohmic loads they can take and the RMS output at a given load. The other part to consider... how much curent will the amp draw VS how much power is available from the electrical system (ALT/BAT) to draw from.
If you have the 3800 series engine, most likely the ALT is a 108A model and your BAT is probably stock rated at ~600 CCA (Cold Cranking Amperes) This stock setup (in good health) can support an amp that draws about 80 amperes of current. That translates to an amp that can put out 600 -1000 watts RMS, depending on the Class of amp used. If you want more thump... plan on some electrical upgrades in the near term.
3. Bridging a 2 channel amp and only use one sub applies to Class A/B amps that need a 4 ohm load for max power transfer. If you have an SVC, 4 ohm sub... this is true. However, if you have DVC's, you can still bridge the amp to MONO and configure the subs so that you get a 4 ohm net load. Usually, a 4+4 DVC setup is needed and wired in series/parallel will net the magic 4 ohms. One can also use a pair of 8 ohm SVC's (wired in parallel) to obtain same results.
Say more about your budget on this pending upgrade. If you like the Bahn sub you have now, can easily get a 2nd one to match and upgrade the Sony amp to something more suitable... a Class D MONO amp makes sense here.
More details to share later, after the budget numbers are established.
Swez
Joepro on 12/18/2003 15:01:23
I have about 285$ saved now in the "sub fund", but after next paycheck and any gift returns and money from christmas will boost my funding. I am hoping to have about 500 to spend on ebay for this. ( where i got my current setup) I will probably buy either the subs or amp before christmas and the other after. I definatly want to get class d amp, but i found something else confusing. I was looking at the audiobahn subs on ebay, and it said they were pre wired for 2 ohm stereo operation. Does that mean i can not use a mono amp with them? anyway thanks for the great reply.
On the engine info, they did not put 3800s in granprix back then, it was the multiport 2.8 or 3.1, i got the 2.8, but it is a better aftermarket alternator. ( went through 2 stock ones, GM altenators are junk) I also have a 1000 watt RMS capactior.
alanjlamore on 12/18/2003 17:44:30
I always thought that getting DVC subs was only worth it if you're going to have 3 or more subs hooked up. The Dual voice coils only allow for more wiring options IMO.
You can usually get the same type of subs (same RMS values and brand) with one voice coil or two, depending on your wiring needs.
This is how I understand it anyway. If you're only going to have 2 subs, then I'd think that getting a MONO amp and wiring the subs in parallel would be the way to go, as long as the amp can take a 2 ohm load (assuming that the subs are each 4 ohms).
I've always been confused with DVC subs too because the numbers get a little crazy when wiring them different ways. A friend of mine had 2 great DVC subs (forgot what brand), but had them wired to only use one voice coil each. His brother saw this and rewired them and now my chest and nostrals vibrate when I sit in his car.
Oh yea, I've always been taught that you should match your watts RMS that all of your subs can handle with the same watts RMS that the amp can put out. If you go by max, then you're not getting accurate numbers since max says what the sub can take, or what the amp can deliver for a very short burst durring one note of music. I'd think that if the RMS values match and the amp's highest max output isn't much more than what the subs can take, you won't have to worry about blowing any subs.
Just my oppinion, hope this helpes,
cplkittle on 12/18/2003 19:10:00
Matching RMS as close as possible for the amp/sub(s) is the standard by which most people go by. I usually go a little larger on the amp when I can. (ie. 2x400w-RMS subs = 1000w amp-RMS). In my opinion this is better because you aren't using 100% of your amplifier's available power at full throttle. Just keep your gain and bass adjustments in check to prevent damage to your speakers.
Joepro on 12/18/2003 23:07:36
The only reason I said DVC's is because they are everywhere on ebay. I have seen that most companys do have the same subs in single voice coils. Perhaps that is they way to go if the price is right. Any amp reccomendations, there are many cheaper amps on ebay, but what they output and their prices scare me, heck my sony amp cost more. I was on another car audio forum and the guys there really spoke highly of JBL amps for best bang for your buck.
Swez on 12/19/2003 09:45:36
Definitely... the JBL Power series MONO amps are potent, reliable and very well priced. Nothing cheap about them and they do deliver more than rated power at 1 & 2 ohm loads. The only think lacking in the JBL Power series, is a subsonic filter. If you use a sealed enclosure, no need for this feature. But if you go ported or BP, them $30.00 will get you a pair of inline SS filter plugins.
A pair of 4 ohm SVC subs will net 8 or 2 ohm loads to the amp, depending on how they are wired. (series or parallel) DVC's come in so many flavors these days, the options are many. But if you like the sub you have now and just want to have more bass, a 2nd matching sub and a more potent amp will give very good results.
No need to dump all you have now and lose all that investment and install work. Can still use that Sony amp for Mid/highs if not a Class D amp... (2 channels are not Class D) and get a larger Class D amp (JBL 600.1 or 1200.1) to power 2 subs. These draw 57/114 amperes of curent respectively at full power. However, under average listening conditions, more like 30/60A., of draw as these are very efficient amps.
Power management may become an real issue if you have a small ALT/BAT now. The CAP mentioned may help keep your lights from dimming to much on large bass hits. But if you add more amping power... make sure your electricals can handle same.
Swez
Joepro on 12/19/2003 23:37:24
So heres what I found. The jbl 600.1 power amp falls right into my price range. At 600 rms at 2 ohms, i was looking at the rockford subs listed on ebay. For the ones that can be wired at 2 ohms in my price range, have a combined rms of 800 watts. Is this too big of an rms gap? For the regular listen, me, will I notice the gap? Assuming I go with that amp, any sub sugesstions?
500$-200$(amp)
300$ for subs and box
cplkittle on 12/20/2003 11:20:41
I believe that the JBL will push the fosgates pretty well. The one thing you have to pay attention to is distortion. Not enough watts is worse than too many watts. If your speakers sound bad or bottom out, or have more of a buzz sounding bass instead of a clean warm sound you could damage the speakers. If you are getting good sound and it dosen't look like the speakers are moving much, you are good. High quality speakers will produce alot of sound with very little visible movement.
Also it depends on the type of box they are in. Generally ported boxes will require right at rms-rms to sound good, sealed boxes will usually give you good sound at +or- up to 100w of the rms.
uochronos on 12/20/2003 23:44:46
If your looking on ebay you can get 2 10" alpine type R subs for 200$ + around 30$ shipping and those would match to that amp perfect these speakers are 300watts rms.. i'm running 2 of them on a 500 watt phoenix gold amp and they sound amazing. if you don like 10's you can get 2 12's for like 30$ more i think it was. same RMS
Joepro on 12/21/2003 02:20:23
Its ironic you mention Alpine r's. i was just looking at them a few hours ago, they sont look too bad. I have alpine 4x6s and im happy with the quality, so i beleive they subs would be good quality too.
Swez on 12/21/2003 07:29:57
There are many subs out there that will sound great at 300+ RMS/ea.
The RF subs are fine... if you are willing to pay a premium for that RF LOGO. Not that RF is a bad product.... just not a good price unless you shop them hard.
You mentioned a 4 ohm SVC Bahn sub earlier. Do you like it enough to buy a 2nd one? If not, Infinity, Alpine, Adire and many others will do a fine job at 600+ watts RMS. The Bahn is a good SPL sub while the others are more SQL in design. You'll get more SPL with a modest amp and Bahn subs as these have very high efficiency ratings. (Ie: requires less watts input, to drive up the dB's)
BTW: RMS matching of the amp VS the subs is very important in Competition rigs. However, in a daily driver it's fine to use subs that are rated higher than the amp. Will work fine as long as one does not push the amp well into clipping and excess distortion.
There are good arguments for going both ways on this topic, but the best way to gage this for most, is with their ears. If the subs are loud but sound strained or un-natural, you may be clipping the amp. That is not good for any speaker... no matter the wattage ratings.
The best way to tell if your speakers are getting clipped signals... get out of the car, open the doors, crack the trunk/hatch and listen from say 10 feet back. If the mids and highs sound shrill or harsh... they are clipping. If the bass is muddy, middy, lacking definition etc., amp may be clipping here too... or a poorly matched enclosure.
Swez
Joepro on 12/21/2003 10:53:09
The bahn sub i have is not bad imo, but it is a lower end sub for the bahn line. (this does not bother me...) The reason I am trashing the idea is that I have people at school offering to buy my old setup, so then I can just get a new one. I got that bahn sub for 40 bucks on ebay brand new believe it or not, and at 500 watts rms, it might not be a bad idea to get 2.....I can not tell the diffrence that it is a lower end sub, or it might be that I dont care, Its bass, its there, and I can hear it, thats my style. I have noticed the rockfords are very expensive, and I might just shop something cheaper, because I do not buy for brand. As for clipping I do not know alot about it, is that when you underpower your speaker?
So if I get the 2 bahn subs, that would be 80 bucks for 1000 watts rms. Id probably would have to move up in power from the jbl amp, 600 rms is most likely way too low for those ones. I really did not see any other SVC subs from bahn with a lower rms. I am gonna shop this hard, so its back to the drawing board for me.
Joepro on 12/21/2003 12:03:02
Ok heres what I have found thus far. Audiobahn is the cheaps(well who didnt know that)
Audiobahn aw121t flame excusion, about 170 shipped for a pair 1100 wats RMS
Audiobahn abpt12t 2 12 audiobahns in bandpass box, 170 shipped 800 watts rms.
2 infinity 120.3se 180 shipped 600 watts rms
these are just a few, any more sugesstions?
Swez on 12/21/2003 13:48:56
Hummm, here's a thought... does your car have a gas pedal? Sure right? Do you always drive it... "pedal to the metal" ? No... not quite huh? Why not? The car may not do well in the long run and run the risk of frying the engine right?
OK, same deal with subs and audio gear in general. We don't crank up our systems to the max all day long. If we did... we get a noise pollution ticket. Run audio gear too hard and sooner or later, something has to give.
And oh... do we listen to our TV set all the way up too? The speakers and amps in a common TV set are only a few watts per speaker. If we turn it up too high, sound will distort and the neighbors will probably complain too. (or Dad will come in and stomp the set to pieces)
OK, if you did get a 2nd Bahn sub (great prices BTW) and used a JBL 600.1, that'd be a very good match for SPL sub applications in the budget range you mentioned. If you shoot for a larger amp to power these subs... can do... but the price of the amp went up and so will power consumption from the electrical system.... (MORE MONEY INTO THE PROJECT THAT WAS NOT IN YOUR BUDGET)
Finally, if you went from a 600 watt amp to a 1000 watt amp for a pair of these subs, can expect (~+2.4?) more dB of SPL from the larger amp. However, current draws will go up nominally from ~45A. (JBL 600.1) to more than 80A., with a 1000 watt amp... if not more, depending on the style of amp used. Question is... is all that expense worth a few more dB of bass SPL? To some, it might not be worth the effort and expense. But to a SPL Comps guy... yes!!! Every fractional dB increase he can get is worth the effort and cost.
Does this make any more sense to you now? Comments
Swez
cplkittle on 12/21/2003 20:26:52
I would recommend the infinity, and would HIGHLY recommend building your own box.
Prefab boxes are good for.. well firewood in my opinion. For an 88 grand prix, I would go with sealed or ported. I had an 89 sunbird, and a bandpass (barely fit in the trunk) did not sound good. Every frequency sound the same, just a monotone boom boom boom, and frequency drops were converted to volume drops. and I was told q-logic boxes were good. come to find out that I was short almost 1cubic foot airspace on the sealed side, and .75 too much on the ported side, and with 3 3" dia ports, it was tuned to something like 600Hz.
changed to a sealed box, and was very impressed. I was running JBL 12's at the time.
I also have 2 audiobahn aw1251t 12" subs, they are pretty powerful, and don't require much to push them, but they are not very clean.
Everyone will tell you that it is better to spend a little more now than alot more later. You can spend 200 now and another 300 later when you decide to upgrade, and have a $200 pair of speakers laying around, or spend that extra 100 now and not have to worry for awhile.
Joepro on 12/22/2003 22:40:05
One more question, I found a set of subs with a box and it says its pre-wired for 2 ohm stereo operation. Would that mean I cannot use a mono channel amp?
Swez on 12/23/2003 06:37:21
Depends on the subs you mentioned and the amp you intend to use on them. The JBL Power series will do 1 and 2 ohm loads with same power output... (600 + RMS). There are other monoblock amps out there that will do 1 ohm, but most are rated for a 2 ohm min load.
What subs are you talking about here? We can review the specs and make some suggestions that may work if you choose to go this route.
Swez
PS Joe, you seem to be waffling about what to do next? It would be most helpful to start at the end goal and work your way back in gear choices. Please, don't get all caught up in "what about these" or how about that" . Figure out what your end goal is and a budget to work with. Once you have the end results (target) well planted in your mind, the rest will drop into place with some help from the team here.
If you are just exploring options, read the posts from others that have been down this road already. This will give you a better idea of what you are shooting for. Once you have that plan firmly planted in your mind, then we can be very effective in leading you to a successful outcome. Try not to get bogged down in the specs that are not clear or mystify you. We can help you understand them as you go... but specs are not the entire picture... the results are.
Joepro on 12/23/2003 09:11:56
I was looking at the audiobahns I found for 155 bucks. It says they are prewired for 2 ohm stereo operation. If I can hook them up to the JBL amp thats the way I was going to go. After I read 2 ohm stereo operation, I know the JBL amp is mono. I am close to my decision, really what ever I can hook up to that JBL amp in that RMS range.
From my research the audiobahns that cplkittle were the same way with 2 ohm stereo operation.
Swez on 12/23/2003 11:07:03
QUOTE: "I was looking at the audiobahns I found for 155 bucks. It says they are prewired for 2 ohm stereo operation." Tells me nothing useful w/o product details or a web link...
Which subs are we taliking about here? Bahn makes about 9 Zillion subs with different part numbers and specs. The product number helps us to look at the sub package and then we can advise you if that product will fit the amp you are considering. Sorry... I left my mind-reading program at home today... hehe
Play ball with me Joe and respond to the questions as we ask for very good reasons OK?
Swez
PS Maybe it's just me, but am feeling like we're not on the same page here Joe... we can get you to ground zero & soon, but we need good feedback on vendor brands and part numbers you are referencing. We can get the details from that and advise if a good fit or not. Better communication here PLEASE !
Joepro on 12/23/2003 11:40:29
All these bahn subs say stereo operation: (that are in my price range)
Abp12t 800 watts RMS SVC(box and all, put together by audiobahn, so space should be right)
aw1251t DVC subs, pre wired for 2 ohm stereo operation. 800 watts RMS
Aw121t SVC 1000 Watts RMS. Stereo operation.
I think were not on the same page because All I wanted to know was if you can hook up stereo subs to a mono amp. If this is the case, I am buying 2 of the above subs with the jbl amp.
Cheers :)
cplkittle on 12/23/2003 11:42:18
the aw1251t audiobahn 12" subs are 4ohm DVC, 400w max.
Do you have a link to this page on ebay? I am not familiar with audiobahn prewiring their subs, be careful not to buy something advertised as new when it may not be. Mine came in a factory sealed box, no prewiring.... Just looking out for you.
erikcooper on 12/23/2003 14:49:10
I am not an expert and not giving any advice, only asking this question in case it may be of importance. I planned to buy audiobahn subs for awhile but when I was at a vendor's shop he told me that while audiobahn was good, they rate their RMS at twice what it truely is. Is this true? He said that if I took say an audiobahn 1000w RMS sub and hooked up say a Fosgate 1000w RMs amp that the Fosgate would blow, while and Audiobahn amp rated the same would not... Comments?
cplkittle on 12/23/2003 19:45:45
did that vendor sell audiobahn products?
Joepro on 12/23/2003 23:11:01
I dont know that audiobahn pre-wired it, I believe it was the vendor, heres link. This is just one, many are selling this combo. Also have links to others. ( I dont know how to do links ill just post the urls)
aw1251t
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3066219052&category=48613
AW1251T
12” NATURAL SOUND WOOFER
45 oz. Strontium Magnet
Power Handling: 400 watts R.M.S.
Frequency Response: 24Hz - 1kHz
Efficiency: 92.1 dB
PHAT Foam Surround
Non- Pressed, Non-Transfer Paper Cone
KM3’ Coated for Virtually No Cone Distortion
2” 4-Layer ASV Voice Coil
Dual 4 Ohm
2 Ohm or 8 Ohm Operation
Mounting Dimensions: Depth; 5 1/4” Hole; 10 7/8” Diameter; 12 1/2”
Lug Lock Terminals
Abp12t
This is from audionbahn, box and subs.
ABP121T
SINGLE 12” TUNED BANDPASS SYSTEM
High Quality MDF Construction
Black Suppleleather Covering
3/8” Plexiglass Window
Blue Interior Neon Lighting
Mirrored Interior Panels
Single 12” PHAT 2” Foam Surround, Non-Pressed KM3(tm) Coated Cone Subwoofers
50 oz. Strontium Magnet
2” 4 Layer ASV Voice Coil
Bumped Back Plate
Extended & Vented Pole Piece
Gold Binding Post Terminals
Power Handling: 400 Watts RMS
Sensitivity: 101dB
Frequency Response: 28Hz - 150Hz
Impedance: 4 Ohm Mono
Dimensions: 15”(H) x 19.5”(W) x 15”(D)
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3067180901&category=32823
This is just one of many also selling this setup
ABP220T
DUAL 12” TUNED BANDPASS SYSTEM
High Quality MDF Construction
Spun Aluminum Venturi Ports
Black Suppleather Covering
3/8” Plexiglass Window
Blue Interior Neon Lighting
Mirrored Interior Panels
Dual 12” Molded, Texture Injected Poly Cone 45 oz. Strontium Magnet
2” 4 Layer ASV Voice Coil
Bumped Back Plate
Extended & Vented Pole Piece
Gold Binding Post Terminals
Power Handling: 800 Watts RMS
Sensitivity: 105dB
Frequency Response: 25Hz - 150Hz
Impedance: 4 Ohm Stereo
Dimensions:
16.5”(H) x 29.5”(W) x 15.75”(D)
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3067154644&category=50567
I would like to go wtih the bahns because of price. I am young enough that I do not need that clean bass sound.
Here is my final plan:
One of those setups, with JBL amp if possible, if not, another amp.
The only thing that consfuses me is how that box is wired to 2 ohms.
erikcooper on 12/24/2003 01:37:16
Yes cplkittle the vendor sold audiobahn products. He was telling me that they are good but not to be dissapointed when I found that out...
cplkittle on 12/24/2003 10:39:27
I double checked my aw1251t subs, they are listed as 400w RMS, which surprised me for some reason I was thinking they were 400w peak. In light of my error, I have been thinking, and you may be right, Erik. I am pushing 2 of these so called 400w RMS subs with a 600w peak kenwood amp. I have it bridged, so I might be pushing 300-325 RMS from the amp-divided by two= 150 watts to each audiobahn. Now, I don't know if either these are bad ass speakers because they sound really good in the bandpass box I built for them, or if they really do double the RMS and I am close to matching it. I have never pushed them to the point of distortion or clipping.... never needed to, they are pretty loud as they are. I will do some research on this...
erikcooper on 12/24/2003 11:47:35
Please let me know what you find out in the research.
Joepro on 12/25/2003 09:45:54
I dont know a lot about car audio, but I have picked up this little bit of info from the local shop. Audiobahn only rates their subs in RMS, never in peak. I do even know if they know the peak. Peak pretty much useless anyway, so thats why audiobahn said heck with it. (this is what I am told)
Joepro on 12/26/2003 23:25:54
"The only think lacking in the JBL Power series, is a subsonic filter. If you use a sealed enclosure, no need for this feature. But if you go ported or BP, them $30.00 will get you a pair of inline SS filter plugins."
Could someone shed some light on the SS filter? Im going JBL amp with BP, so I dont know a lot about this filter I need.
uochronos on 12/26/2003 23:46:37
well a subsonic filter usualy filters out everything below 20hrz mainly because you cant hear it much below that and to keep the sub from over excursuion. in a band pass or ported box you need to have a filter that matchs the frequency that your box is tuned to... for instance if your box was tuned to 30hz and at 30hz its excursion was 15mm and at lets say 15hz it would have an excursion of 25mm(these are totaly made up numbers) and lets say its maximum excursion is 20mm well in that case you wont want your speaker to ever hit 15 hz and 25mm because that would be 5mm past maximum excursion which very likly would damage the speaker. i hope this helps its not really all the details but its the way it works in simple terms
Joepro on 12/27/2003 16:29:25
I can not find them anywhere, are they really just inline crossovers? Where can I find a set of these?
compvr15s on 12/27/2003 16:41:27
http://thezeb.com/caraudio/harrision_labs.html
Joepro on 12/29/2003 11:42:45
As you all know Im on a tight budget, would you hesitate to buy this? Or should I fork it out and get a new one?(not that much more)
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3068013645&category=18797
cplkittle on 12/29/2003 19:44:43
First of all, have you decided on the subs you want yet? and what are their RMS watts?
I almost bought one just looking at it until I saw this line in the description:
FACTORY RECONDITIONED - TO NEW SPECS
I would definitely email this guy and ask him a few questions first.
1) who is offering the warranty (some companies don't do online warranties)
2) what are the new specs, and what were the old specs?
3) can I get a picture of the actual amp itself.
These are good amps, just be weary of reconditioned or refurbished items.
another thing:
NOTE: These are expected to arrive on November 10 th and will start shipping then.
how long has he been trying to auction these?
Joepro on 01/6/2004 17:33:30
Got the Jbl amp and the audiobahn box with the SVC subs. The JBL amp has 2 sets of speaker terminals, so can I just run a wire from each negative to one on each sub and same for positive for parallel? will that work?
swez on 01/6/2004 20:48:13
One set of terminals to each sub is fine. These terminals are wired parallel internally. As long as you don't go below 1 ohm loading, should be fine.
No need for a SS filter if sealed. The enclosure will naturally roll off subsonic frequencies automatically.
If using a ported box, protect your subs by using a SS filter that is close to ported frequency... Ie ported at ~30 Hz, use a 20 - 30 Hz filter to block all below tuning frequency. If you blow your subs trying to save $30.00, I'd say that would be an expensive mistake we all can live without huh?
Swez
erikcooper on 01/6/2004 22:13:54
Wouldn't you want those 20hz waves? Wouldn't that just be deeper bass? Is it not good to tune them at 20hz or is there somethign I am missing?
Joepro on 01/6/2004 22:14:03
Ya I went to our local car audio store and asked for a SS filter and the guy laughed at me. He said where are you going to find a signal below 20 hz. He did not even sell them....Anyway I walked out went home and ordered a pair from PE.
erikcooper on 01/6/2004 22:36:20
I would love to have some subsonic frequencies coming through my subs so that I get the vibration but now sound. That would be cool. Probably not good for me but still. So what is the lowest frequency we actually get through our subs?
swez on 01/7/2004 01:15:06
Most folks cannot hear much below about 30 Hz. Below that, we feel it. The reason for SS filtering on a ported box, is that frequencies below the tuned port are very hard on subs. The cones become unstable, these frequencies are not very useful in car audio applications and these subsonic (below what we can hear) really eat up amp power.
In better quality HT applications, we might want to port down to 20 Hz. That's where movies come to life... Volcano, Dante's Peak, Jerassic Park, The Matrix and such....
Swez
Munchiesyumm on 01/7/2004 01:58:42
hey Swez..
I like your movie choices.. SMILE
So cplkittle you think the Bahn's are over rated? Where did you guys read/find this out? I would be interested to know. Maybe we should start a new post on it and have thoughts shared about this topic?
erikcooper on 01/7/2004 02:18:58
I think we decided that they did not overrate munchies. I can;t remember how but there is more discussion in another post.
I would need to tune at that low of frequency then, as I plan to put in a DVD player.
In case anyone was wondering, this is a daily driver, BUT, it will be a show vehicle, once I get that much money invested. Once I learn fiberglass fabrication the interior will be amazing...
cplkittle on 01/7/2004 08:47:27
as far as frequencies below 20 Hz, once the driver reaches the tuned frequency of the box, let's say 30Hz, the excursion is at its lowest. Below the tuned frequency, the excursion increases at a phenominal rate, maxing out at around 7-10Hz below tuned freq, and if it were possible, it would double every octave lower. (one octave down from 30 is 15, one octave down from 15 is 7.5, then 3.75 and so on). so a driver that has an xmax of 12mm would peak at around 22Hz. At 11Hz, the driver will try to reach 24mm, at 5.5Hz, 48mm and so on.
These numbers are not accurate to the 'T'.
Joepro on 01/8/2004 23:04:49
I am amazed already at how much better the JBL amp is that the sony. Its pushing 200 more watts Rms, and does not take as nearly as much voltage out of my electrical system. I haven turned it up really loud,(since the subbies are new), but even in places my voltage meter would just up and down with the sony it does nothing. What a much more efficent amp! I like the subs system too it sound very clean to my ears. Here what I ended up with:
Jbl 600.1 power series amp
Auduibahn abp12t tuned banpass system with 2 12inch SVC subs at 400 RMS each.
Other system components:
Pioneer 550 premier deck
Alpine 4x6's
sony 6x9;s (soon to be replaced now, but I got them for free)
Sounds nice for an entry level system, at least I think so!
I wanted to finnaly say thanks for all the help from everyone on this topic!
Joepro on 01/10/2004 20:34:49
Well, all my hard work with the system has just gone to ****. I totaled my car last night..... (deer) I am going to retrieve my subs and head deck tomorrow. I know the head deck still works because it was the only thing still on after i crawled out of the car. I wasnt there when they filpped it over, but from what I hear the subs and amp are still intact. Im just gonna have to sell it anyway to pay my fine for crossing the center line anyway, but thanks again for helping me out. Maybe someday I will have a car to build a system in again, but thats pretty far off.
swez on 01/10/2004 22:25:33
Oh man, am so sorry to hear that happened to you. Do you know what "Deer Whistles" are? They are inexpensive plastic devices that mount to the bumper of the car. They emit a high pitched noice deer can hear from a goodly distance and supposedly put the deer on the run, back into the woods. I have used them in Deer Country and never had a problem... but that may just be "dumb luck" on my part.
I hope you are OK and you gear can be reteived for another install.
Swez :-(
Munchiesyumm on 01/12/2004 21:04:29
I have a 1989 Pontic Grand Prix my self, they are pretty decent cars. But extremely slow, I never wrecked it but it was my grandma's car and she wrecked it a few times, I sure wouldn't want to get in an actsident with a Grand Prix. How did it hold up? I was always afraid if I hit anything I would been a goner.! Been close to hitting a Deer my self, I sware the breaks only work when you don't need them to.
Mine was 2.8ltr v-6 automatic with 134,000 miles, stock tape player (impossible to remove for less than 250 dollars) 2 door coupe completely faded interior and the paint was in horrible shape. But the engine keeps on chuckin along. It's too bad you got in a wreck.
Try looking into getting a job living with you're parents which I do really gets you money to save up for things. I thought I remembered reading you were in high school.
good luck and hope you get it all worked out
erikcooper on 01/13/2004 00:22:14
I am a sophomore in college (20 yrs. old) and I still live with mom and dad. Why not? They pay for my school and all and most of my money I make is just for me.
Munchiesyumm on 01/13/2004 01:07:19
I am sixteen years old and a I am a Junior in HighSchool. I turn 17 next month Feburary 13th 1987
Joepro on 01/13/2004 12:19:46
Do you know what "Deer Whistles" are?
~I do, and I dont bother with them, my dad see a substantial amount in the body shop hit by deer......
As for the car, I suppose it held up well for what it went through.
impossible to remove for less than 250 dollars
Not in an 88!
Give me a pic of your dash, if its anything like the 88 I can rip it right outta there!
As for me I am a senior in high school, and I have a job. After this It will be a cold day in you know where before they help me buy a car now. Thats just how they are.
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