behringer amp to power sub

[joem]

Hi,
Can one power a sub using an external amp such as the Behringer A500 and make use of the bass management of my receiver (Denon 2803) to set up the crossover points etc.
If yes, what would the pros and cons be for such a set up.
My main concern would be input sensitivity of the amp versus a plate amp.
Thanks for your help.

[bogie]

It'll work, but you're giving up your crossover (which I never really used much anyway, since I run dual subs, and like a little extra "thud"), and more importantly, if the amplifier will go LOW, you're going to lose the rumble filter. Which may allow drivers to overexcurse.

> Hi,
> Can one power a sub using an external amp
> such as the Behringer A500 and make use of
> the bass management of my receiver (Denon
> 2803) to set up the crossover points etc.
> If yes, what would the pros and cons be for
> such a set up.
> My main concern would be input sensitivity
> of the amp versus a plate amp.
> Thanks for your help.

[Paul O]

> If yes, what would the pros and cons be for such a set up. My main concern would be input sensitivity of the amp versus a plate amp. Thanks for your help.

The input sensitivity can be a concern, though not with the A500 as it has RCA inputs. What will be a concern is the subsonic filter as you'll see if you read any of Bogie's recent posts. The best way to do this is with a crossover/processor like the DCX2496 or DBX Driverack, because it gives you all the tools you need. Parametric EQ for response contouring , fully adjustable crossover for as many bands as you need, adjustable low cut filters, limiters for driver protection, and level matching with pro style amps.
This will give you the features many plate amps have built-in, although you will have much more control. But really, until you get above 500w into multiple subs, it may not be cost effective.

[damkor]

I would pick one with a sharp 30 Hz high pass, like the Euro 1500. That, in conjunction with the receiver's xover is all you need. I think it's a great option. You don't need all those xover controls for the sub.

Gain is not an issue. The gain controls on the power amp are doing the same thing as the ones on the plate amp. All the way down you will hear nothing, and all the way up is unity, 0dB from the receiver, no attenuation.

[Paul O]

It's not quite that simple. The low cut filter on many Pro amps is only 12db/oct. And the input sensitivity is usually between 1v and 1.5v. That means that even with the amp gains all the way up, the pre-outs of a typical AVR, which are in the .5v range, won't be enough to drive the amp anywhere near it rated output.

[Pete Schumacher ®]

> I would pick one with a sharp 30 Hz high
> pass, like the Euro 1500. That, in
> conjunction with the receiver's xover is all
> you need. I think it's a great option. You
> don't need all those xover controls for the
> sub.

> Gain is not an issue. The gain controls on
> the power amp are doing the same thing as
> the ones on the plate amp. All the way down
> you will hear nothing, and all the way up is
> unity, 0dB from the receiver, no
> attenuation.

Why would you want a sharp 30Hz Highpass?