[fschris]

Please school this Noob....


I have a Yamaha rcvr that supports Bi-amping....


Not sure if I totally understand how this works.


If I was looking at a Amplifier that said it was "bridgeable" that basically means if it has 2 channels you can turn it onto one channel and have more power correct?



Is this the same as Bi-Amping on my Yamaha rx-v665.. Where I can tie 2 channels together to get more power for say my Center channel? I know I see speakers sold that support Bi-Amping.


I wanted to take my center channel and give it more power as I use the pre-outs to a external amplifier for the other channels....


I think though that Bridging and Bi-Amping must be different ?

 

[rdgrimes]

Bridging amps is a completely different thing. With bridging, 2 channels are summed into one, with double the power and double the noise and distortion. Not possible with any AVR that I know of, this is a feature limited to amps.


Bi-amping is the dividing of the audio signal into 2 channels, low freq into one and HF into the other. True bi-amping is usually accomplished with stand-alone active crossovers between a pre-amp and multiple amps. It also requires speakers that are specifically designed for this type operation. Many speakers offer "bi-wiring" type connections but are not actually set up for bi-amping internally with completely separate pathways for HF and LF inputs.


There are also examples of tri and quad amped speakers. In those cases the speaker either have no crossover internally, or have a very specialized crossover.


Many current AVRs offer a "bi-amp" feature that doesn't really fall into any of the above categories. It's not usually clear if the output from the 2 channels is crossed over into HF and LF components or if they simply output the same signal into 2 channels. Available power MAY be increased, depending on the total number of channels driven.


The major factor to consider is the speaker, not the AVR. Unless the speaker has completely separate internal pathways for HF and LF inputs, the benefits of bi-amping are small, if any.


With AVRs, the fewer the number of channels you drive with them, the more power is available to the channels that are driven. So simply using an external amp for some channels will greatly increase the power the AVR can provide to the remaining channels. The v665 can push close to 90 WPC if it's only driving 2 channels, but closer to 40-50 if driving 5 or 7. If you are driving 5 channels with the AVR and use the other 2 channels for bi-amping, you are actually decreasing the available power to each channel.


I use a v665 to drive only 2 surround channels and the rest go to an external amp.

 

[schan1269]

Depends on what you are trying to accomplish with the bi-amp.


The bi-amp in your receiver is either passive or active...


If passive, it is a complete waste of time. Always has been, always will be.


If active(which means it actually uses the crossover in your receiver) it will only use the crossover that you have, meaning 40hz to 200hz, which will "miss" your speakers necessary crossover by at least 1000hz.


If your receiver does use the crossover, it is really a "throwback" to those people out there using passive subwoofers...nothing more.


And, no...the owners manual won't tell you which form it uses. You have to connect it to two pairs of speakers...and see what happens. You'll either have two pairs of speakers "doing the same thing", or you'll have one pair playing everything over the crossover, and one pair playing everything under the crossover...and again...


The manual won't tell you which way yours is.

 

[fschris]

Thanks... that helps clear things up! Appreciate the replies.