Bi-amping with Bi-wiring at opposite end for extra power? Will it short?

Lostcar

Novice Member
Hi all, I havent seem to find this answer in the threads.

I have a yamaha 5.1 receiver and it has a bi-amp option. I am looking to drive my B&W speakers harder as i only have two. So all other channels are disabled currently.

Im use to connecting speakers from car amps so slightly different.

Can i use bi-amp mode to connect to a single 2 post terminal speaker using bi-wiring method? Essentially 2 steel brackets (Or cables) at both terminals on the receiver to drive one speaker? Essentially the opposite of 4 post terminals binders on speakers but at the receiver end. Obviously keeeping all positives and negatives apart from each other. Not sure that makes sense.

Some one said no on youtube but didnt say why? Will it short or something?

Anyone know?

Thanks!
 

noiseboy72

Distinguished Member
You can, but it won't be any louder...

Power is voltage x current. Current is voltage divided by impedance- or resistance in a DC circuit, so as your speakers have a fixed impedance, just increasing the current capability of the amplifier won't increase the volume. You will need to increase the voltage to increase the volume.

You can bridge some power amplifiers to increase the voltage swing, but not domestic AV receivers. Connecting in parallel is possible but not advised, and as I say, it won't increase volume, it will just allow you to drive a lower impedance load.

Bi-amping doesn't generally increase the volume of a speaker, as the same rules above apply. What it does do is reduce interaction between the drivers and if the amplifier has insufficient current available, it may reduce distortion and provide a very modest power gain.

You also need to consider the power supply in the amplifier. If you look at the rated power output, you will see that it cannot drive all channels to maximum power, and this is the limiting factor, not the individual channel power.

Long story short, you won't be able to get more power out of your amplifier using any other connection method. The same rules apply to car audio, as the maths is the same.
 

Mark.Yudkin

Distinguished Member
Youtube is correct. You cannot simply connect two distinct power amplification channels together, as proposed, and you will short your amplifiers if you try.

I think Noiseboy missed the part about your speaker's not having support for biamping, as his description is about biamping in general, but doesn't mentions your self-destruction case.
 

noiseboy72

Distinguished Member
Youtube is correct. You cannot simply connect two distinct power amplification channels together, as proposed, and you will short your amplifiers if you try.

I think Noiseboy missed the part about your speaker's not having support for biamping, as his description is about biamping in general, but doesn't mentions your self-destruction case.
You can connect multiple amplifiers in parallel to 1 load, it's done regularly in pro audio setups to decrease the minimum impedance that can be driven. Line arrays are quite often connected to present a 2 Ohm load to the amplifier and a stereo amp will be run in parallel to give 1 low impedance output.

I would not do it with a domestic amplifier as it would probably confuse the protection circuitry - and it won't make the speaker play any louder.
 

jwlawler

Active Member
Youtube is correct. You cannot simply connect two distinct power amplification channels together, as proposed, and you will short your amplifiers if you try.

I think Noiseboy missed the part about your speaker's not having support for biamping, as his description is about biamping in general, but doesn't mentions your self-destruction case.

Seconded. You will be connecting two outputs together. It is unlikely that the amplifier is designed for this. It is liable to have a bad effect.
 

noiseboy72

Distinguished Member
Seconded. You will be connecting two outputs together. It is unlikely that the amplifier is designed for this. It is liable to have a bad effect.
You can connect 2 identical amplifiers with the same input signal together in parallel, there's no electrical reason to prevent this and in biamp mode the amplifier channels will be presented with pretty much an identical signal.

I would not advise doing this with a domestic amplifier, as it could confuse the protection circuitry and more importantly, the power supply will be the limiting factor.

There's no shorting or electrical potential difference between the 2 amplifier channels when run in this mode and the voltage output will be unchanged. The amplifier channels will run cooler as each will only need to supply about half the current- assuming the load doesn't change.
 

Lostcar

Novice Member
Excellent answers! Thank you all for explaining thoroughly! I think i will stick with using 2 channels only on stereo mode. :)
 

Jamie

Distinguished Member
If the amp is only 5.1 then I very much doubt it has settings for bi-amping anyway, what's more common is amps with 7 or more channels having the option to have 7.1 OR use the extra rear channels for bi-amping.

If your amp has A+B main speaker terminals then these would use the same amp channels anyway.
 

jwlawler

Active Member
You can connect 2 identical amplifiers with the same input signal together in parallel, there's no electrical reason to prevent this and in biamp mode the amplifier channels will be presented with pretty much an identical signal.

I would not advise doing this with a domestic amplifier, as it could confuse the protection circuitry and more importantly, the power supply will be the limiting factor.

There's no shorting or electrical potential difference between the 2 amplifier channels when run in this mode and the voltage output will be unchanged. The amplifier channels will run cooler as each will only need to supply about half the current- assuming the load doesn't change.
I am not really disagreeing, just being more cautious. Some amplifiers might be designed to accept it; some might happen to cope; as you say, some might get confused. Can I be sure that some would actually be damaged? No, but I would not risk using expensive equipment in a way not supported by the manufacturer.
 

password1

Distinguished Member
There is a place for bi wiring.

I used to have a pair of speakers which I bi wired.

Copper cables to tweeters and silver plated cables to the mid/bass drivers as I found the silver cables was a little too bright.

Using the same cables for both HF and LF makes no difference.
 

Dobbyisfree

Well-known Member
As said, I think what you would like to do is to bridge the amps. Very few AVRs will do this, the only I can think of are some Onkyos, I know the TX-SR875 did it for example. You could set bridge mode for the fronts and, indeed, more power to fronts.

Of course, like any other AVR (including yours) the power is shared across the internal amps anyway and in most cases the promised 2 channel RMS power into 8Ohms 20Hz-20kHz at x level of distortion is only available if only two speakers are connected.

You don't say what model your AVR or speakers are, it could be that more power would be of little benefit anyway.
 

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