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Subwoofer Amp Recommendations

I've added a stereo pair of VBT Magellan passive subs (fantastic, BTW)to my 2-channel system. VBT recommends using their 200S amp, which I have---and it is good---and I could get another for stereo, but as I'm using a Tact 2.2x, I don't need the crossover/volume functions in their amp, and would rather not have to put the signal through another set of electronics.

My considerations have ranged from the new Carver Pro amps (but I'm not happy about their connections as I'd need new cables or adapters) to used Adcoms/NADs/Aragons. I've also considered PS Audio and Sunfire, but not sure if I need to spend that much just for a bass amp.

A friend suggested the new Panasonic 45 digital receiver which takes a digital input (saving me the expense of a DAC, but I already have an extra anyway).

Your thoughts and experience would be appreciated.
richards
elevick
2,636 posts
 
Cheap older amps simply won't cut it! Buy a pair of Janis 1/a's on ebay for $350/pair. Only 100 watts but clean and powerful down to the last octave. Your old carver will just muddy up things in the upper bass region and never get down to the 20-50hz region.
ritteri
223 posts
 
Slew rate is very important in my book. It has to do with the dynamic ability of an amplifier and how quickly it responds to sudden changes in signal.

Being flat down to DC I feel also is a good indication to of how well an amplifier can reporduce low frequency signals. Many amplifiers in the bottom of the frequency spectrum slope off in the last octave slightly giving a "dry" thin sound. But I have found that amps that can reproduce a flat signal down to DC basically have much better detailed bass that is rich sounding.

And just because an amplifier is rated to respond down to DC doesnt mean it can reproduce the signal in a linear fashion.

I personally wouldnt suggest an amp thats 25 years old btw. My father had an old pair of those he sold about 10 years back. Nothing special at all.
eldartford
4,262 posts
 
Ritteri...My point about slew rate is that a subwoofer signal does not involve any "sudden changes", so the ability of an amp to track such changes is immaterial.

The Kenwood LO7M is a true DC amp, with not a single capacitor in the signal path. If you put a steady voltage on the input, say +0.1vdc you will get a steady voltage say +20vdc, at the output. It is truly linear down to DC, unlike the Aragon which you say rolls off (probably minus 3dB) at 5 Hz.

Is response only to 5Hz adequate? Sure, but you are the one who raised the issue of bandwidth below 20 Hz. I am sure that your Aragon is a very fine amp, but its virtues would be wasted driving a subwoofer.
danner
202 posts
 
... for a description of damping factor and how it works try: www.crownaudio.com/pdf/amps/damping%20factor.pdf
elgordo
530 posts
 
I'll second Eldartford's recommendation of the Kenwood L-07M. If you've never heard these as bass amps, you should. Absolutely fantastic!
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