New Home Theatre Sub

[dark_avenger]

hey everyone, i'm looking to build a new powered sub for my 5.1 system. at the momment the woofer i'm using bottems out at about 40-50Hz. I want to build something capable of 20Hz flat if possible/fesable.

The amp im thinking of using is this one
http://www.peavey.com/products/brows...item/116310/PV(R)%20900.cfm

Can deliver 600w into 4Ohm in bridged mode with built in 150Hz crossover.

any suggests on driver/box design and amp would be greatly apreciated.

David

[dark_avenger]

i'm thinking the 15" version of this sub

http://www.kicker.uk.com/compvx.html

Specs say down to 18Hz how big a box and what sort of design would the box have to have in order to get that low?

[GM]

Greets!

With no T/S specs, no way to figure it out.

GM

[hooha]

Those units are basically fart drivers. Certainly not something you would classify as producing quality output.

As GM mentioned, no T/S parameters either.

Best,
Mark

[dangus]

There are T-S parameters in the pdf spec sheet:
For the CVX15:
Fs = 21.5 Hz
Qts = 0.304
Vas = 7.3 cubic feet
2 or 4 ohm dual coils

I threw those parameters into Perfect Box, and it suggests a vented cabinet 3.6 cubic feet for an F3 of 29 Hz. Not at all bad for a home sub.

But, there's probably some other driver that's better value for money, unless you can get a special deal on this driver.

[auplater]

Originally posted by hooha
Those units are basically fart drivers. Certainly not something you would classify as producing quality output.

As GM mentioned, no T/S parameters either.

Best,
Mark

dunno 'bout that... I built these 8 ft^3 with comps and they reproduce into the mid 'teens (with room gain) @ 110dB in a 15,000 ft^3 room, designed as ebs... priced right too @ ~$40/driver and that's with the 12" drivers... and these are just the comp drivers.

Wife calls the couch the "vibrochair" seeing as on most hometheater material, the couch actually levitates when strong IMPACTS are reproduced...

[GM]

Originally posted by hooha
Those units are basically fart drivers. Certainly not something you would classify as producing quality output.

Greets!

?? Not being into car audio beyond despising all the inconsiderate a$$holes driving around with their one note rolling boomboxes drowning out my tunes, I'm not sure what this means or what about its construction makes it one, so don't know what kind of alignment (if any) can deal with it.

GM

[GM]

Originally posted by dangus
There are T-S parameters in the pdf spec sheet:

Greets!

If these specs are reasonably accurate a well damped Vb = Vas, Fb = Fs (or a bit lower) TWQT could be pretty good in a HT app, especially if corner loaded. This slightly larger (~246.2 L) tapped pipe (TL) might be even better, though not knowing its excursion specs this peak SPL may just be a 'pipe dream' if not corner loaded and there's not enough room gain to help it below ~32 Hz. It should still pound pretty good if not though and it doesn't have an obvious 'gas' problem to mar its performance.

GM

[dark_avenger]

thanks for the advice, i'm abit new with speaker design. i'll have a look round and try to find a more value for money driver. i like the pipe design i'll have a look into that. thanks!

[Moondog55]

I built a sealed box using the earlier Comp VR, it's a huge box, about 155 litres and stuffed to make it seem larger.
The problem seems to be a very peaky output at around 120 Hz so I stopped using it in my cheap home theatre setup ( it is currently sitting in my shed unused)
Come around and listen before you make a decision, E-mail me
Ted