Am i doing this wrong? Kef Reference 5 Bi-Amping

[id.ray]

Greetings ASR Family,

I’m new to posting here and have a couple of technical questions that I think I will be able to get straight forward answers from.

I recently came across my “Endgame” speakers at a price I couldn’t say no to, the Kef Reference 5, side note they are amazing.

I’m also a sucker for vintage Yamaha power amps. That’s all I have really known other then AVRS. Maybe it’s the bouncing red lights. The simple geometry, but probably mostly budget constraints. As I picked it up for a Hundred bucks….

I have everything hooked up and it sounds awesome to me. I stream Tidal connect to a Bluesound node 2i, SE out to the Yamaha C-60 pre amp, from there SE out to matching Yamaha M-60 Power amp. And from there using modest speaker wire to the Reference 5. All is good and I really couldn’t ask for more.

As a audio junkie on a budget…. Scrounging fb market etc., I came across another Yamaha M-60 power amp for you guessed it, a hundred bucks and picked it up. Seems to work great and preformed the basic maintenance checks from the service manual. Setting the pots to 10mv at idol.



Now comes the real question…. And maybe I’m nuts “this is where you guys come in”

I would like to hook up both Stereo “non bridgeable” power amps, one to each speaker.

My thought was From Each channel of the pre amp, Y-split to both cannels of the power amp. Remove the link of the KEFS and run “left channel” to the highs and “right channel” to the lows and do the same for the other speaker, effectively Bi-amping.

Is this a great idea, a bad idea, a pointless idea and why,

I have attached the specs of the power amp, the pre amp and the impedance curve of the ref 5.

Thank you all so much for any input.

 

[id.ray]

Found this on YouTube, maybe he's doing what im describing....

 

[NiagaraPete]

I would like to hook up both Stereo “non bridgeable” power amps, one to each speaker.

Normally one amp would be bass LR and the other would be treble LR. First though you need a crossover (electronic or digital). You also need speakers that are provisioned for bi-amping.

 

[killdozzer]

I wouldn't do it that way. (OK, I wouldn't at all, still, if I wanted to play around, I wouldn't do that).

You're going for some strange option where it's not mono blocks (and is not bridged and you don't want to for some reason), but the configuration is LIKE mono blocks.

Left channel needs left lows and left highs. The right channel needs the opposite.

You'd split the signal with Y, which means both power amps get the full signal... And you'd send half of the stereo image to your highs and half to your lows.

 

[killdozzer]

Side note:

M60 is very capable and very low distortion, measured down to 2 ohms. So, at least one thing is certain. You could do it for some personal subjective aesthetics. You shouldn't expect much improvement.

 

[id.ray]

Normally one amp would be bass LR and the would be treble LR. First though you need a crossover (electronic or digital). You also need speakers that are provisioned for bi-amping.

The Speakers are capable of bi-amping by removing the links/jumper

Wouldn't there be an advantage to using one amp per speaker, as there would effectively be the same "cross talk" to each channel and strain the amp less as each one is has its full available power to the whole channel as apposed to the again identical amp. trying to just drive all the bass and the other just driving the mids and highs

 

[NiagaraPete]

I wouldn't do it that way. (OK, I wouldn't at all, still, if I wanted to play around, I wouldn't do that).

But that is how bi-amping works.

You're going for some strange option where it's not mono blocks (and is not bridged and you don't want to for some reason), but the configuration is LIKE mono blocks.

No, that is how bi-amping works.

Left channel needs left lows and left highs. The right channel needs the opposite.

You could do it that way but without a proper crossover you're wasting your time.

You'd split the signal with Y, which means both power amps get the full signal... And you'd send half of the stereo image to your highs and half to your lows.

Huh?

source > pre-amp > cross over > amp 1 treble to treble on speaker amp 2 to bass on speaker

 

[NiagaraPete]

The Speakers are capable of bi-amping by removing the links/jumper

One problem solved.

Wouldn't there be an advantage to using one amp per speaker, as there would effectively be the same "cross talk" to each channel and strain the amp less as each one is has its full available power to the whole channel as apposed to the again identical amp. trying to just drive all the bass and the other just driving the mids and highs

No, yes, maybe. If you're stacking the amps it makes sense to have the bass amp on top for best cooling. Your way doubles heat on one side.

 

[killdozzer]

But that is how bi-amping works.

No, that is how bi-amping works.

You could do it that way but without a proper crossover you're wasting your time.

Huh?

source > pre-amp > cross over > amp 1 treble to treble on speaker amp 2 to bass on speaker

This is a more common way of bi-amping

What you say makes sense only with a x-over. I don't see OP mentioning one.

source > pre-amp > cross over > amp 1 treble to treble on speaker amp 2 to bass on speaker

I don't see this mentioned.

 

[NiagaraPete]

both power amps get the full signal..

Defeats the purpose of bi-amping.

This is a more common way of bi-amping

What you say makes sense only with a x-over. I don't see OP mentioning one.


I don't see this mentioned.

Like I told him a crossover was needed to proper bi-amp. The picture above is what I also told him.

 

[killdozzer]

Defeats the purpose of bi-amping.

Like I told him a crossover was needed to proper bi-amp. The picture above is what I also told him.

Then there was a misunderstanding. And you're correcting me in what I tried to correct in OP's question. read again:

I would like to hook up both Stereo “non bridgeable” power amps, one to each speaker.

See. This is why I said I wouldn't do it that way. And I don't think you read it closely. As I said, the way he described it, it looks like a configuration for mono-block, but amps left in stereo.

I think you misunderstood. You and I are saying the same thing, but he asked for something that doesn't look healthy to me.

 

[voodooless]

The idea makes perfect sense essentially. Since the amps are not the same, you use one for the lows, one for the highs. That should even out most of the differences as long as you match the gains. So yes, this would work.

Defeats the purpose of bi-amping.

That IS bi-amping. Anything else makes it an active system, not just bi-amped.

Now the question is why one would do all this if you don’t make the system truly active? Basically it’s not worth all the trouble. You probably won’t notice the difference if you do a proper controlled test.

 

[killdozzer]

Defeats the purpose of bi-amping.

That's what I'M SAYING he shouldn't do for the exact reason you're mentioning. I'm not saying do it that way, I'm saying it makes no sense.

 

[NiagaraPete]

That's what I'M SAYING he shouldn't do for the exact reason you're mentioning. I'm not saying do it that way, I'm saying it makes no sense.

Agreed.

 

[id.ray]

The idea makes perfect sense essentially. Since the amps are not the same, you use one for the lows, one for the highs. That should even out most of the differences as long as you match the gains. So yes, this would work.


That IS bi-amping. Anything else makes it an active system, not just bi-amped.

Now the question is why one would do all this if you don’t make the system truly active? Basically it’s not worth all the trouble. You probably won’t notice the difference if you do a proper controlled test.

They are both the same amplifier both Yamaha M- 60 i attached the manual in the first post

 

[voodooless]

They are both the same amplifier both Yamaha M- 60 i attached the manual in the first post

Then you could do it either way. But I would not bother.

 

[fpitas]

Then you could do it either way. But I would not bother.

I agree. About all you could accomplish is to change the relative levels of the drivers. Which, if the speakers are competently designed, is a bad idea. Otherwise if you get the relative levels back to what the factory intended, you've accomplished basically nothing.

Bi-amping is a boutique idea with no basis in science. I guess people do it because it's different.

 

[NiagaraPete]

Bi-amping is a bouitique idea with no basis in science. I guess people do it because it's different.

Active bi-amping is the cat’s meow.

 

[fpitas]

Active bi-amping is the cat’s meow.

I have a fully active system, with DSP crossover at line level to three separate amps. So, you're preaching to the choir

 

[NiagaraPete]

DSP crossover

Is the next level. I ran a tri-amp active system for years but not with DSP.