Quickie!

[Tomogchi]

How you guys doing tonight.
I actually found this website off of myspace (baja? sorry if i butchured your name)
Anyways... I'll give the complete setup..
1200 watt xplode amp(2 channel), powering 2 12" 1200 watt xplode subs
2000 watt pyle dryver amp (good for about 800-900 watts, also 2 channel), powering 2 12" 900 watt xplode subs (neither amps are bridged)
4 infinity speakers, 2 6x9's in the rear, 2 4x7's squeezed in the door
complete 2/0 gauge wires running to/from amps.
Pioneer DEH-P3600 200 watt cd player. Im using both sets of preouts, with a Video/mono audio cable (like a 10 guage rca wire, apeice) running to the amps
All in a '94 civic dx (hatchback)

Question 1) How the heck can a basically stock Civic (with stock alternator) power this????? When i do local bass competitions, my car just about dies during a bass hit. (I'm in the proccess of buying a beefed up alternator for the civic to power my stereo equipment).

Question 2) I've been told both positive and negative things about capacitors. Should I invest into a couple 1.0's? (i think a generic rule of thumb is 1.0 cap for 1,000 watts?)

Question 3) I have the subs in the hatch facing up (home-made Pine box, box weighs about 40 pounds, but makes the 900's sound mean), and the set in the back [seat] facing towards the front of the car. Is there any way to make the subs more "fungshwei" (sp?), so that it is more audible from outside the car, but not loosing the bass inside the car?

Yeah, i lied, a quickie turned into a full out thread. lol (yeah, i kinda showed off....) Theres alotta money (in my eyes) in the sound system, gotta show it off. (if you can't make them fast, make them loud... lol)
Thanks,
Bill

[badjuju342]

Welcome to the site, I hope you find it a very good way to waste time.
Now to answer your questions:
1. You're on the right track , an aftermarket alternator will solve a lot of your problem. If you're using the stock lawnmower battery they installed in those , trash can and get an Optima or equivalent.
2. In your case , a couple of caps would help. They basically are for power surges , not continous high volume so they would benefit you.
3. I would really need to see pics of your set up to get an idea of what you need to do on your subs.

[NoChrome]

If your running out of power when it hits hard you definately need a cap, there are systems out there that have the equivlant of 6farad caps in a box. Do you know the proper way to hook up a cap? I have seen them done wrong so often its not even funny. Another option is to get an additional alternator, and just run two. A friend of mine was running alot of power and his alternator kept burning up brushes, so we, and a really good shop put in 4 chain driven alternators.

[Tomogchi]

Im not exactly sure on how to wire up a cap, i believe i would run the cap in parrellel with the amp/battery, wouldnt i?

How high of an amperage alternator should i look for? I was thinking of a 110 amp or a 160 amp alternator. (anythings better than my 60 amp alternator i have now. lol)

Wow, that totally slipped my mind. Would i be better to go for an ultima red top or yellow top, or trying to fit a deep cycle battery somewhere?

And I will post pics when i get back from work tonight, Im actually walking out the door now

Thanks,
Bill

[NoChrome]

To wire up a cap all you gotta do is put it after your BIG fuse from the battery to the system.

First- install a splice in your biggest power wire, take that extra end and run it to the power input on the cap.

Step B.- the other end of the cap goes to the chassis ground.

Lastly, secure the cap so it dont go no where, and be very very very careful with charged caps, because they WILL blow a hole in your hand, if you dont beleive me charge one and put a hotdog accross the terminals, then imagine if that was your finger.

[NoChrome]

While I do agree that a battery will help and a cap will too, they wont fix any thing you need a bigger alternator, but how big depends on your total power useage, and I am not smart enough to know that, Ill look for a caculator that will tell you.

[LWillmann]

Problem with a Cap is that if you're running the tone for more than an instant (using a sweep for example) then the cap's juice is gone in the first moment. They're designed more for short bursts. If you're using a sweep (like many people do) then it'll be wasted. Now if you're using single freq tones, then the cap might help you.

You'd be better off running a 2nd battery, with a bigger alternator.

I ran 1500 watts RMS (3000 peak watts) in my car with a 140 amp (stock for my car)for a while, but a 200 amp is what I really needed. When running the 200 amp, I didn't have any real problems.

[Tomogchi]

Umm.... Whats a Sweep?
Would a Couple caps work better? like three .5's instead of one 1.5?


I still need to get pictures up. I think im just going to do the pics at night with a big ass flashlight. lol

Maybe the Neons will light the sube up enough?
Hmm, pictures in maybe 5 minutes....
Bill

[NoChrome]

Im so sound expert, I deal mostly with electricty, which explains the bad hair, but a sweep is a long hard hit, I think.

And as far as caps go, a 1.5 farad is the same as three .5 farad caps, a farad is just a measurement of how much electricty it can hold, I think that .5 caps would charge faster, but they would also discharge faster. But not sure.

[LWillmann]

No, a sweep is where the track starts at say 20Hz, and sweeps to 100 Hz. They're normally used when first starting with a box to find the general area where the car/box/system combo peaks naturally, then competitors normall focus on that particular range with single-tone tracks, finally zoning in on the one frequency where it's loudest and they just 'burp' the system at that frequency.

One more thing to consider with the caps, if you wire multiple caps up, you're adding extra connections, each connection adds resistance and voltage drop to the mix.

IMO, rather than a 1.5f cap, if you really want a cap, get a 50f super-cap. That might help out better. BUT, it's STILL not going to replace the big alternator/2nd battery option.

[NoChrome]

Shows what I know about steros.

A fifty farad cap? Are you serious, that thing must be huge! You could blow a leg off with that thing

[Tomogchi]

a 50 cap?

DAMN. the thing would most likely weigh as much as my car does, lol... j/p.
I actually got pictures of my setup, and was wondering how i would load them onto here? do i have to do the thumbnail thingy. or am i able to upload rigt onto the site?

Bill

[NoChrome]

in your post on the right hand corner there is a link that says "Tomogchi's Gallery" click it, then click the "manage my gallery" link and go from there

[LWillmann]

http://www.rockfordfosgate.com/products/product_details.asp?cat_id=5&series_id=40&family_id=87&item_id=86619&locale=en_US - 25f Fosgate Cap.

http://cgi.ebay.com/20-FARAD-DIGITAL-LCD-DISPLAY-COMPETITION-CAP-CAPACITOR_W0QQitemZ280001957044QQihZ018QQcategoryZ 75388QQrdZ1QQcmdZViewItem - 20f cap on ebay.

http://cgi.ebay.com/40-FARAD-COMPETITION-DIGITAL-DISPLAY-LCD-CAP-CAPACITOR_W0QQitemZ270002236726QQihZ017QQcategoryZ 75388QQrdZ1QQcmdZViewItem - 40f cap on ebay.

http://cgi.ebay.com/SOUNDSTREAM-SC-40CA-40-FARAD-DIGITAL-CAPACITOR-NEW_W0QQitemZ130002152120QQihZ003QQcategoryZ75388Q QrdZ1QQcmdZViewItem - 40f Soundstream cap on ebay.

[Tomogchi]

http://img.photobucket.com/albums/v628/bilfanator88/P6110027.jpg
(12" xplodes, 900 watt series) those subs run off of this amp... Dont laugh at them, they still hit, and hard at that. They just didnt like the bridged pwoer of this amp.

http://img.photobucket.com/albums/v628/bilfanator88/P6110028.jpg
^----- "2000" watt amp. good for about 900 watts or so

http://img.photobucket.com/albums/v628/bilfanator88/P6110026.jpg

i have these four, all on there own mini amp (2 amps came from a '94 caravan, 2 came from a 94 caddy)

(red wires run to the mini amps)

http://img.photobucket.com/albums/v628/bilfanator88/P6110024.jpg
^---- 12", 1200 watt sony xplodes

(continued below....)

[Tomogchi]

http://img.photobucket.com/albums/v628/bilfanator88/P6110025.jpg
^----- Xplode 1200 watt amp (unbridged)

And i Went and baught a a new battery, the beefed out one (the autozone version of the optima redtop), it deffinetely helped, my other 1 year old battery couldnt handle it. but now its time for a cap, Im prolly going to invest into a 20f cap. And then Ill do a high output alternator, then i should have no issues. WOO! lol

I'm going to build a few new boxes, but i was wondering: Will one sub hit harder in its own cavity? I was thinking about making corner boxes, and fitting them all in my "trunk" (one sub in a corner), with the amps in the center.
Should i have them all facing towards the roof when i make new boxes? Or facing each other (diaganolly)?
I want the best quality i can get (and the 900's are getting replaced eventually, im kind of waiting to see how long they can still thump for.. lol), while still maintaining the Power that it has during the bass competitions.
(wow, i dont know if that made sense)
Thanks,
Bill

[LWillmann]

The determination of if subs will hit harder when single or paired or grouped, is determined by the signal fed to them. If you feed them all the same mono signal, then putting them in the same enclosure would be good. If you're feeding two of them the right channel and the other two the left, then you should group the two like channels together.

Pointing them at one another wouldn't be too wise, as the soundwaves from the facing subs would be fighting one another and you might end up with some cancellation.

It's also best to keep the subs to the same size and model, so that frequency responses are the same, it also means that the enclosure design is much easier.

[Tomogchi]

okay...
so facing each other is a bad idea. if they were all facing up, would that be better?
or would it be better to have the subs reversed (i never actually saw a point to it, but maybe it owrks...). like, instead of seeing curve of the foam surrond, you see the magnet.....
Should two be facing the front of the car, with 2 facing the back? or side to side??
Sorry, im just trying to figure out how to work this all in a tiny car.
thanks,
bill

[LWillmann]

I think I remember reading that by installing them basket-out, you lose a little SPL because the speaker is designed to eminate sound from the front of the cone, but I think it's more that the basket of the speaker would block some of the surface area of the cone on the back side, so you won't get all the sound that the cone is generating as it vibrates and moves. So I would recommend you mount them basket-in, unless they're a 'designer' style sub like the Audiobahn FlameQ series with the flame shaped basket.

As for pointing them, I'd try to point them ALL in the same direction. In your case, that will probably have to be up.

And I will be willing to bet that if you build an enclosure for just two of them and got it to the right dimensions and airspace for one pair, that you'd be louder with less power than with four subs and more power in a less than optimal box.

For example, one of the boxes you're using appears to be a bandpass box, with the plexiglass front removed. Well bandpass boxes are usually made too small for normal vented use, and the front (clear) champer is the part that should normally be vented when designed properly. Bandpass boxes are boomy boxes, not designed with sound quality in mind. Perfect example: Two Pioneer 12" (two-fer $99 jobs) in a Best Buy bandpass box with a 400 watt Jensen amp did 142db in the trunk of a 2000 Neon. We went to a single 15" in a 2.5ft^3 vented enclosure with a 600 watt amp and did 147.5 db. Normally doubling the power only gives you 3db. So with less cone area (single 15" vs 2-12") and less than double the power, we gained 5.5db. It would have taken roughly 4 times the power to do that with the 2-12" box.

I would seriously consider picking ONE pair of those subs, and building a good, solid enclosure for it, rather than just trying to cram a bunch of subs in the trunk. I think you'll be happier in the end.

[Tomogchi]

its not that im im just grabbing any random set..... its jsut that some subs sound soo much better in one vehicle, and the same set will sound like dog doo in another. i've shifted through subs in there, and havent decided what sounds better. the box i actually got for 15 bucks (the one that did have a plexiglass cover, but it wouldnt fit in his mustang, so he chopped it and then sold it.
umm... how did you hit 147.5 with the 2-99$ deal? what pioneer 12's did you have?
i hit 143 with roughly 2000 watts and 4 12"s....
and i thought mine was decent. Although my walmart cheapie (decibel meter) may not be the most accurate thing in the world.
So upwards would be the best bet, okay....
and im going to stick to one set of subs eventually, lol.... Just got to find the ones that suit me the best...
Thanks,
Bill

[LWillmann]

I would figure up how much air space you have to dedicate to a speaker box, then find subs that will work within that space.

The 2-$99 deal was a 142 in a bandpass box with a 400w Jensen amp.

The 147.5 was a single 15" sub in a good ported enclosure with 600w RMS of power.

This was on an AudioControl meter with USACI a few years ago.

On that same meter, my Firebird (shown in my sig) with 2 GS Designs 12" subs and 800w RMS power did 147.8 db ported to 35 Hz.

[Tomogchi]

I'm deffinetely leaning away from the xplods, as good as they have been, my 1200 watt subs are beginning to crack...
Going to do a set of l5's or l7's.... Seen a set of the solos, in a civic of my year, and they were insane with a 1200 watt xplod amp, bridged.. I just havent decided how deaf im going to go.....
Would the solo's be happier in a ported, sealed or bandpass box?
woo, tuesday means payday and payday means one or two subs, depending on who has what in stock....
(side question) do the L5's/L7's still need to be broken in for the full 20 hours?
Bill

[LWillmann]

I would go with the L7's, probably 12's and YES break them in GENTLY!!! They'll get louder as you go, at the same volume level.

[Tailwind]

Usually with caps smaller units parralleled together to reach a given uf value will give you a lower overall DCR considering the smaller caps are of the same quality as the large one . That makes for less resistance or impedence overall and that means more power to the amp. 3 or 1 same power available. same charge time minus the diff in dcr and that is minute at best. But when I build a crossover I look for every option to increase perf. or sound quality. Go for it.

Caps are a plus even on a 20 watt amp as they act as shock absorbers to the alternator period. as well as the powe fluctuations the amp sees, saves rectifiers. they supply the surge needed whether small or up to full uf value. Only for an instant. Usually 99 time out of 100 thats all that is needed. It causes the amp to see a constant voltage much more so than the same system without one. or two. even if they go out before the amp is done the alternator still has a more gradual amp boost. The alternator sees more gradual elevations in amperage draw rather than quick fast surges. Increase alternator life. Have you ever been hit by static electricity, figure thats a pico farad, a micro farad is 1000 times that, a farad is 1,000,000 times that. Now picture that arcing on your earlobe.

As well they will absolutely kill you in the right situation. They are like a charged heavy battery that dumps its entire capacity instantly if grounded. If you are the ground path. OUCH!! Ive seen fingers split open, it aint pretty.
Also in some situations Ive seen big caps jump 8inches or so and arc like a static discharge. Be carefull with big caps. I have built alot of speakers and sound systems and have been bitten myself. If you are unsure about a cap as far as charging it with a lamp or a resistor or how to properly discharge one you owe it to yourself and anyone around it to know how it is used safley. Usually they come with instructions that are pretty simple to follow, but many buy used caps after another makes an upgrade or something and they dont allways include the directions.

Im so sound expert, I deal mostly with electricty, which explains the bad hair, but a sweep is a long hard hit, I think.

And as far as caps go, a 1.5 farad is the same as three .5 farad caps, a farad is just a measurement of how much electricty it can hold, I think that .5 caps would charge faster, but they would also discharge faster. But not sure.