sub-woofer requirements

[delta9blazer]

i'm building a box for my lady's ride, and i want to know the air space requirements for subs. i read somewhere awhile back that 10's need one cubic foot of space, with more or less air for bigger or smaller speakers. is this a good rule of thumb?
if not, what is the standard?
she has a kenwood deck (cd/tuner). we added kenwood satellite tweeters up on the doors, and replaced the stock speakers in the rear deck and in the kickpanels with same-size kenwoods. can you tell i like staying brand specific?
anyway, i want to add an amp, running one ten or twelve in a box in the trunk. nothing thunderous. i may also add a smaller amp to power the mids, and run a cross-over.

so, any suggestions?

<font color=purple>delta9blazer</font color=purple>

 

[laketex]

Air space on subs varies drastically depending on the sub. A 10 inch solo baric will have much less airspace required than a 10 inch Digital Designs 9000 series. You need to call the manufacturer or a dealer and find out the recommended space requirements for your sub. And they will give you two numbers, both for ported, which is more space and one for a sealed box.

As for an amp, you don't need much to run one sub, just go for quality. I personally have a Kenwood KAC 606 with built in crossover, which bridged and turned up halfway, punches my ESX ES12 very well. I hit 132 dB on the dash and this amp is touted as a mids and highs amp. Stay away from brands like Pyramid, Jensen, and other stereo sale specials, but I'm sure you know that. I've seen a few of these Kenwood amps on ebay for $60-$70 and plan on buying another for my girlfriends truck. Audio Art and older RF amps (read black case) are good bets too. And if you have 2 sets of RCAs, you can always run another for your highs later. But just having a crossover on your bass filters out so much distortion, you'll be very happy with just a sub amp unless you're a true audiophile like me

Durant, Ok
'79 Blazer in progress

 

[BlueKnight]

laketex is right every woofers q,VAs, f are different. Call the manufacturer tell them the type of box you are building. sealed, ported, bandpass, and so on. They will give you the exact internal space you need. Also power minimum 50 watts to run each sub. Anything over a 150 watts you might want to use a stiffening cap for the deep lows. BTW they will also ask you what frequency you will cross it off at so be prepared.

<font color=purple>79' K-5 396cid 600hp, TH350, NP203</font color=purple>
http://79blueknight.homepage.com

 

[Blazer79]

What is a stiffening cap?

<font color=black>//////
What the heck!...Drive it like gas is $0.50/gal!!!</font color=black>

 

[BlueKnight]

It is a capacitor that goes before the power into your amp. It stores voltage for your amp. When a bass note hits it saps voltage away from the amp. This causes distortion or not a complete note or deep bass effect. A stiffening cap is ready to give your amp that extra boost when it needs it.

<font color=purple>79' K-5 396cid 600hp, TH350, NP203</font color=purple>
http://79blueknight.homepage.com

 

['73 K5]

The battery and alternator move slowly. They charge and discharge slowly. Since music is fast, especially bass notes, you need something that can feed your amp quickly. A capacitor can do it. 1 farad of capacitance for every 750 RMS watts is a good rule of thumb. If you buy a cap get a 20 VDC capable one for voltage spikes...stay away from the 16 VDC ones.
You really shouldn't need one for what you're doing. With one sub and a medium sized amp, I wouldn't worry about it. The number one warning sign that you may need a capacitor is when your headlights/dome light dims really bad when the bass hits.

'73 K5
Chevy good...Ford bad

 

[KingSmoth]

You should not have a need for a cap with little power running through your system. I have 450W running through my system right now(had 750W, but disconnected one amp; however, I have another 400W amp to hook up with the 300W and 450W), and I have no dimming, except when I run Bass Mechanik tracks, etc. However, due to installing three amps I will be putting in a 1F cap(1F for every 1000W of power).