Foam sub box lining affecting tuning?

[Outbacksound 1]

Ports are the same as vents.  Interchangeable words.  If you want to say round port or PVC port, that's understandably different than a slot port.

Allright, then I was going to order 4" double flared round ports, but I don't have the money, so for now I'm going to build a sealed box at 1.25 cu. ft. per sub (recommended) and probably stuff with a 1/2lb. of polyfill per sub chamber at first.  Might add more, and hopefully I'll be able to pound some sound with this sealed box.  I'll post how it sounds after they break in.  However, I'm still not sure if this amp should be the one I grab.  Never used anything Kenwood, but this amp seems to be decent (way better than what I have, anyway).  Would anyone else concur that this amp, in this price range ($400 is as high as I can go) would be worth it, or do Kenwood amps suck?

http://www.crutchfield.com/p_113X1200M/Kenwood-Excelon-X1200M.html?tp=115

[jcarter1885 995]

I would personally look into a class D amp to push your subs, will be less strain on your electrical. Just my .02.

[Outbacksound 1]

I would personally look into a class D amp to push your subs, will be less strain on your electrical. Just my .02.

It says it is a class D amp. What's the difference between class d and ab? Like you said, a d will be lees strain on my electrical system, but is that the only difference?

[jcarter1885 995]

I would personally look into a class D amp to push your subs, will be less strain on your electrical. Just my .02.

It says it is a class D amp. What's the difference between class d and ab? Like you said, a d will be lees strain on my electrical system, but is that the only difference?

My fault I seen the M at the end of the model number so I apologize. If that was the only difference, then that is an important difference (less strain is a good thing on the vehicle and audio system which wil reguire less electrical upgrades and more money being spent).

Class D Amplifier: For subwoofer applications, Class D amps are very efficient and their small size offers installation flexibility. Before amplifying an incoming signal, a Class D amp converts the signal to digital. Digital signals can be amplified very efficiently, so you get a lot more power with less current. Less input current reduces power supply size and generates less waste heat, thus reducing the heat sink size. The amp then converts the amplified signal back to analog.

[KU40 173]

For subwoofer application efficiency difference is really the only difference worth noting.

I have a 4 channel Kenwood amp in that same line and it does the job. The fan on it is noisy though. I've never clamped the output to see if it does rated, though. Lower line Kenwood anything sucks, but the excelon line has always been fairly decent.

[Outbacksound 1]

Thanks guys, good things to know. Yeah I remeber reading about how the amps convert the analog signal to digital and back, kind of forgot about that. I don't think I'll hear the fan over these subs, so I should be good

Another thing, is it ok to have the speaker wire connections on the back of the terminal cup buried by polyfil, or is that a potential fire hazard? I'd run the wires to the top of the box, so they wouldn't rest in the polyfil, but that won't look as clean.

Edited November 4, 2009 by Feel The Bass

[KU40 173]

I'd just cut out a hole in the polyfill around the terminal cup. It doesn't have to cover every square inch to be effective.

[Outbacksound 1]

I'd just cut out a hole in the polyfill around the terminal cup. It doesn't have to cover every square inch to be effective.

Yeah, that's what I was thinking. Would a 1/2lb. per cu. ft. be enough, or you just have to play with it until it sounds best?