Bi-Amping Question

[s1977]

Hi All !

I am thinking of bi-amping my speakers (B&W 804S) using two dedicated stereo amplifiers. I am thinking of powering each channel by its own amplifier. However my question is, assuming that I do not use an active crossover, would it be okay if i pass the same individual channel input signal to both stereo amplifier inputs. It would be akin to shorting both channel inputs, I would assume.

Is this the right way to do it?

Any responses would be helpful.

Regards

[djoffe]

Driving both channels of the amp with the same signal will work fine.
Yes, it is essentially shorting the (left and right) inputs together, and it shouldn't be a problem.

[planet10]

That is typically how one does passive bi-amping... inputs paralleled to get the same signal (your pre-amp will see half the input impedance) and then identical power amp channels to drive each half of the passive XO in the box.

dave

[s1977]

djoffe and planet10

Many thanks for your responses. I wasn't sure if shorting both the amplifier L/R inputs would cause any issues from a design point of view. I didn't want to damage the amps and then realise that it doesnt work fundamentally. Thats why I asked.

Many thanks again!
regards

[h_a]

Hi,

I'm not sure I understand correctly what you want to do - use a separate amp for every stereo channel? One amp for left, one amp for right speaker? What advantage do you expect?

Biamping is usually done with 2 (or more) amps driving different frequency ranges of both speakers. The advantage is a reduction of intermodulation products. Has even more advantages if done actively, in other words without passive crossover.

If I understand correctly, you don't short, but parallel the amp inputs. That essentially loads the preamp more as it sees only half input impedance. This will be in many cases no problem, but I fail to see the advantage of doing so.

Have fun, Hannes

[s1977]

Hi Hannes
Wouldn't paralleling the inputs to the amp appear as shorted to it though? Maybe I am mixing terms here. I was worried that I may damage the amplifier if I did that.

Anyways, I intended to supply the HF/LF inputs separately via individual channels with the source via an active crossover. That way the power demands of each channel could be handled effectively, more so in the case of the LF channel.

That was the intent. I am happy if you want to advise me on that.
regards