I had serious doubts (Gainclone powered LT Sub) and...

[PaulHilgeman]

I was correct.

I finished the enclosure tonight and installed the drivers. I used CoolEdit Pro to simulate the Linkwitz transform with an Fc of 25Hz and a Q of .6. As most of you know I have built a few gainclone, and they were the only thing that I had around to power my sub. I fired them up, one gainclone powering each driver. The drivers are Peerless 831857 12" woofer, 9mm xmax. There are two of them in a 50L enclosure.

The crafty ones out there will know that I need about 18dB of gain at 20 Hz to meet my goal. Indeed, that is how I filtered it. Got everything hooked up, and it sounded good at low volumes, and made some good deep bass, at medium listening levels. It had that nice clean sealed box sound, but when the low stuff started to hit, there was no ease to the sound, it was stressed, and the amps were getting pretty warm. I turned it all of the way up, and there was some serious clipping going on.

I could not get the drivers anywhere close to xmax. Based on the LT spreadsheet form the FRD Consortium, I was getting about 2.5mm. I reveresed one of the connections so that I basically had a dipole subwoofer, which got the speakers much closer to xmax, but I still couldnt get the drivers to do much distortion at full volume.

I am thinking about getting the 350W amplifier over at: http://www.rythmikaudio.com/nonservo_product.htm I think it will be plenty for this set-up, and it is only $140. take a look at the datasheet, looks like the guy knows what he is talking about, and it uses a 600VA transformer, with a Class A/B at about 55% efficent, it looks like it has a solid PS behind it too. You dont see many Manufacturers specing that out.

Questions? Comments?

-Paul Hilgeman

[Illusus]

Hi,
That amp looks good, although I'd pitch in the extra $15 for the better opamps(next model up). You can also try www.apexjr.com. They have a large variety of nice plate amps at good prices. Check the "amplifiers" and "new arrivals" sections, I recommend the Apex senior plate amp(it looks very similiar to the one at the link you provided)... good features, 250W @ 8ohm, 350W @ 4ohm for $159...the specs and schems are provided on the page. I bought one of these to drive my sonotube TL sub, I am very satisfied, although the auto-on feature sucks, but to be fair it sucked on every plate amp I have tried, I just use the switched power out on my HT amp. The 300W Cerwin Vega amplifier on the new arrivals page looks good too.
Have fun and Good luck.

[PaulHilgeman]

Thanks for the heads-up!!!

I'll look into those