In Search of a Passive Subwoofer Amplifier

Class D is not "digital". 

Roscoeiii,

Sorry for the long delay in responding. Blame it on that double-u O R K thing.
Yes - I live in Chicago - Downtown. My speaker builder is John Van L (Van L Speakerworks). Damn genius, this guy. I am going there Saturday 24 March to retrieve a pair of repaired speaker cables.
I've asked him to start on the amp-build (on-board) portion of a pair of bass towers for his 'Duet' speakers. The bass towers for these employ a pair of Canadian-manufactured 7" bass drivers. One is in a sealed enclosure and the other is vented. Both are active (no passive radiator - not that those are bad, or anything).
John seems sold on the digital amps provided by Bash which manufacture amps specifically intended for use as bass amps. He's got an incredible fine ear - no question. Says he's listened to other configurations and still stands by the digital choice. I have a pair of REL G-1 subs for my main system which employ on-board 700W A/B amps. These are wickedly fast, although I believe the drivers and other aspects of its design bring much to the quick response party. This is why I'm curious about other subwoofer amp designs/choices other than Class D. That said, I do have a lot of faith in John's designs as he's built the best pair of speakers (my bias, of course) in an over-the-top pair of his Quartets I got last year. If you know of John, ask him about them. There truly isn't anything like them.

By all means, please feel free to reach me offline @ scott_wolff1@hotmail.com

I'll look forward to anything you can suggest.

Cheers,

Scott

Behringer a500:

http://www.behringer.com/EN/Products/A500.aspx

I've used two of these to power the sub modules of my Zu Definition 2's for the last few years and they've been perfect. Real transformers, about 500 watts into mono, very little heat, great power and control. And pretty sure I got the pair delivered for under $350. Too good to be true, but actually true. I haven't had one thought of replacing them for any reason other than a potential future failure.

Parts Express has the SA-1000 amp which is a sleeper without audiophile credentials making it easy to miss. It has lots of power, high damping factor, is NOT digital, but does produce lots of power with almost non-existent heat. It is licensed technology from Sunfire. You can see in the description the down-tracking converter, the secret to the high power low heat in all of the Sunfire amps. I think about $400. You could drive both subs mono or at your budget, the better choice would be to get two, run in stereo for dramatic soundstage improvement on those recordings with true stereo bass.

I throw in a vote for the Crown XTI series of pro amps. It has a built in DSP that let you configure all kinds or parameters via software on your laptop...such as crossover frequency, crossover slope, notch filters, gain, delay, etc...Very flexible and a variety of models with varying power. I have an XTI-2000 on a pair of 15 inch passive subs and have been pretty happy with it..

Scott,

Are you here in Chicago or just your sub builder? Shoot me an email if you are local (if you can't do that thru A'gon I use the same user name on AudioCircle & AudioAsylum)

Johnnyb - thanks for responding - and good question. Budget I'd like to stay in is around $1000, possibly a little more. In response to Roscoeiii - sub impedance is 8 ohms.
Optimally sub amp should have an on-board crossover, but if not, I'll consider one with an external x-over.

Scott

Anthony Gallo sub amp?

What is the impedance of your subs and what kind of power do you need? I use a pair of Emotiva BPA-1s, each bridged for my two dual NHT SW2 subs. If you want more conamtrol for fine tuning, maybe grab something like an NHT X2.

You didn't mention a budget.

Off the top of my head it seems that a Red Dragon M-1000 would be a powerful, economic choice that would deliver lots of speed, power, current, and clarity.