RX-V861 bi-amping question

[bo-cephus]

Hello Everyone,
Have a question: My Yamaha RX-V861 has 9 speaker posts, 7 for the "typical" 7.1surround sound and 2 other ones. These 2 other ones are either for a "second zone" or "extra SP", which apprently is for 2 more smaller front speakers.

I have some B&W 602 S3's in front l/r and wanted to bi-amp them. Curiously the Yamaha manual states I can used my 2 rear center channel speakers for rear center channel sound or for bi-amping. But it doesn't say whether or not I can use the 2 "extra" posts in the front for bi-amping (which would be my preference, since I like to use my rear channels for rear surround). Does anyone know if I can use the 2 "extra" fronts for bi-amping my L/R fronts? Thanks.

BTW, I see the 805 has a similar configuration, and allows for bi-amping using the extra fronts, but I've heard rumors that the Yamamha and Onkyo have different internal configurations.

 

[jcPanny]

Receiver Settings

Your Yamaha receiver can assign 2 of the amp channels to Surround Back speakers OR powered zone 2 OR bi-amp main speakers. I wouldn't recommend using the biamp feature on this type of receiver because the power is not rated for all channels driven so there is little or no benefit.

Your receiver may also have the A and B speaker terminals. These are designed to power the A OR B speakers, not A AND B and are connected to the same amp channels. If you set the receiver to power A AND B the amp will see a load of 4 ohms or less and could cause the receiver to overheat and go into shutdown.

 

[Seth=L]

Your Yamaha receiver can assign 2 of the amp channels to Surround Back speakers OR powered zone 2 OR bi-amp main speakers. I wouldn't recommend using the biamp feature on this type of receiver because the power is not rated for all channels driven so there is little or no benefit.

Your receiver may also have the A and B speaker terminals. These are designed to power the A OR B speakers, not A AND B and are connected to the same amp channels. If you set the receiver to power A AND B the amp will see a load of 4 ohms or less and could cause the receiver to overheat and go into shutdown.

I agree, bi-amping on a receiver is rather pointless. You won't be able to notice any difference in power or SQ.

 

[bo-cephus]

Thanks. Would the same thinking apply to the Onkyo 805, or does it make more sense for the 805 vs. the 861?

 

[Seth=L]

Thanks. Would the same thinking apply to the Onkyo 805, or does it make more sense for the 805 vs. the 861?

The same would apply for the Onkyo. FYI: the Onkyo has a more powerful amplifier section than the Yamaha.

 

[gene]

I agree, bi-amping on a receiver is rather pointless. You won't be able to notice any difference in power or SQ.

I would beg to differ depending on the speakers and usage of the receiver. If you're running just a 2CH setup, than by all means I'd biamp, especially if the bottom half of the speakers are bass units that go down in the 20Hz region. This would yield better control for driving the bass from a dedicated amp while the other amps focus on the top mid/tweets.

I wouldn't recommend using the biamp feature on this type of receiver because the power is not rated for all channels driven so there is little or no benefit.

Yes but the ACD is mostly a bogus test. You would be surprised at how little power is being used by the tweeter in a bi-amp configuration.

I would at least try it before discounting the usefulness of this feature. Back when I had a Denon AVR-5803, when I biamped my front channels, I heard a significant increase in fidelity and bass control.

 

[fmw]

Let me offer this in response. The purpose of biamping is to provide additional amplifier power to a speaker system because the existing amplifier power is inadequate for whatever reason.

In a receiver all the amplifiers feed from a common power supply. As long as the supply can produce enough current and voltage all will be well. When it no longer can do that, then all is not well. This is true whether we connect one amp or 2 amps or 15 amps to the speaker system. The common power supply is the limiting factor, not the number of amplifiers.

Biamping from amplifiers in a receiver that are powered by a single power supply is truly pointless in every sense of the word. How can it be otherwise?

 

[gene]

Let me offer this in response. The purpose of biamping is to provide additional amplifier power to a speaker system because the existing amplifier power is inadequate for whatever reason.

In a receiver all the amplifiers feed from a common power supply. As long as the supply can produce enough current and voltage all will be well. When it no longer can do that, then all is not well. This is true whether we connect one amp or 2 amps or 15 amps to the speaker system. The common power supply is the limiting factor, not the number of amplifiers.

Biamping from amplifiers in a receiver that are powered by a single power supply is truly pointless in every sense of the word. How can it be otherwise?

What you say is mostly true but biamping is more than just getting more power to a speaker. Its about delivering that power with more control and isolating each driver with its own amp. The true benefits of biamping are achieved with active crossovers, etc, but there are still advantages to passive biamping as I have seen via flagship receivers from the likes of Denon and Yamaha. Its questionable whether the Yamaha 861 biamped would improve performance over single amped but it doesn't hurt to at least try it.

 

[obscbyclouds]

As a quick aside, I use the biamp feature on my onkyo 705. Mostly because I only run a 5.1 setup and otherwise the rear surrounds would be completely unused. However, I was not able to decern any audible difference with 2 CH music, Hires multichannel music, or movies. I am using Axiom M60 main speakers. I say use it if you want, but if you're running 7.1, there's probably more benefit to that than passively bi-amping your main speakers.

 

[gene]

As a quick aside, I use the biamp feature on my onkyo 705. Mostly because I only run a 5.1 setup and otherwise the rear surrounds would be completely unused. However, I was not able to decern any audible difference with 2 CH music, Hires multichannel music, or movies. I am using Axiom M60 main speakers. I say use it if you want, but if you're running 7.1, there's probably more benefit to that than passively bi-amping your main speakers.

the benefits of biamping would be more noticeable on speakers that actually have dedicated bass units like the RBH 1266-SE for example.

Most definately I'd opt for doing full 7.1 over using the extra 2 channels for bi-amping.

 

[fmw]

In order to bi-amplify properly you need to replace the speaker's passive crossover network with the external active one located between the preamp and the power amp, not simply add an active network or add another amp to the speaker terminals. If you don't disconnect the passive crossover, you aren't isolating anything or accomplishing anything. You are just bi-wiring with some additional amplifier power.

If you are suggesting that the OP buy an external power amp and an active crossover and then enter the speaker enclosures to disconnect the existing passive networks, then I agree he should try it. If you are suggesting that he just hook two more receiver amps up that share a common power supply then you would have to subscribe to the audibility of bi-wiring to suggest that it could provide any benefit at all. Since I don't believe in the audibility of bi-wiring based on objective testing, I contend that simply hooking up another amp sharing the same power supply is just a waste of wire.

 

[gene]

In order to bi-amplify properly you need to replace the speaker's passive crossover network with the external active one located between the preamp and the power amp, not simply add an active network or add another amp to the speaker terminals. If you don't disconnect the passive crossover, you aren't isolating anything or accomplishing anything. You are just bi-wiring with some additional amplifier power.

If you are suggesting that the OP buy an external power amp and an active crossover and then enter the speaker enclosures to disconnect the existing passive networks, then I agree he should try it. If you are suggesting that he just hook two more receiver amps up that share a common power supply then you would have to subscribe to the audibility of bi-wiring to suggest that it could provide any benefit at all. Since I don't believe in the audibility of bi-wiring based on objective testing, I contend that simply hooking up another amp sharing the same power supply is just a waste of wire.

Than your understanding of electronics is very limited. Biwiring is NOT electrically equivalent to passive bi-amping even if the amps are all run on the same power supply. You are still providing an easier load to each amp by passive biamping and there are still isolation benefits even without removing the crossovers and replacing with active ones.

I have tested this numerous times with my RBH Sound T-30LSEs and my Denon AVR-5805. The bass portion of the T30s is a two ohm load and having them powered off their own amps even in a receiver with shared power supplies produced a significant sonic advantage. Granted the 5805 is an exception since its power supply is more robust than most dedicated 7CH amps but it was still quite amazing to hear the difference.

 

[fmw]

Than your understanding of electronics is very limited. Biwiring is NOT electrically equivalent to passive bi-amping even if the amps are all run on the same power supply. You are still providing an easier load to each amp by passive biamping and there are still isolation benefits even without removing the crossovers and replacing with active ones.

I have tested this numerous times with my RBH Sound T-30LSEs and my Denon AVR-5805. The bass portion of the T30s is a two ohm load and having them powered off their own amps even in a receiver with shared power supplies produced a significant sonic advantage. Granted the 5805 is an exception since its power supply is more robust than most dedicated 7CH amps but it was still quite amazing to hear the difference.

Ok but then the electronics knowledge of some EE's is also very limited. They would disagree with you. Take care.

 

[PENG]

Ok but then the electronics knowledge of some EE's is also very limited. They would disagree with you. Take care.

fmw, I am not sure what gene's background is, but I am sure he knows much more about AV electronics and I do. However, I can tell you that even biwiring would offer some isolation/segregation effect because the crossover of the speakers would partially enforce a pair of wire to carry mostly (not all) high frequency while the other pair carries low frequency signals. I know gene would disagree with me on this one, but I know I am right; it is not about the audio effect, just pure electrical theory.

In the case of passive biamping the isolation effect is much more significant in that the crossover network at the speaker would enforce (preferentially) one amp to deliver mostly (again, I am not saying all) higher frequency signals leaving the mostly lower frequencies to the other amp. And I think gene would agree on this one.

There is no argument that active biamping can do a better job and I assume we all sort of know the reasons. If you search the web you will find one or two articles that talk about why biwiring or even passively biamping not making any difference. One of them even posted diagrams and calculations but those calculations appeared to (me anyway)be based on some misconceptions. Again, I have no intention to debate whether such signal isolation/segregation (I am using this term loosely)has any effect on the perceived sound quality. I just feel like pointing out as I did once or twice before, the difference, based on electrical theory.

 

[gene]

fmw, I am not sure what gene's background is, but I am sure he knows much more about AV electronics and I do. However, I can tell you that even biwiring would offer some isolation/segregation effect because the crossover of the speakers would partially enforce a pair of wire to carry mostly (not all) high frequency while the other pair carries low frequency signals. I know gene would disagree with me on this one, but I know I am right; it is not about the audio effect, just pure electrical theory.

My background is located here:
http://www.audioholics.com/Members/Gene/biography-1

I have had my hand in amplifier design for nearly 7 years prior to quitting my cubicle engineering job to pursue the dream of Audioholics full time.

As for your comments about biwiring:
I find it a little hard to swallow since the combined signal folds back to a common amplifier and thus the amp has to deal with the back EMF regardless. In any event, biwiring looks cool, it lowers the effective gauge and is a cheap tweak provided you don't purchase expensive esoteric cable

I recommend reading this article on speaker cable gauge:
http://www.audioholics.com/education/cables/speaker-cable-gauge

and we do have a series of articles about bi-wiring you may wish to check out:
http://www.audioholics.com/education/cables/bi-wiring-from-amplifier-to-loudspeaker

 

[bo-cephus]

Thanks folks, for the great (and spirited) discussion. I was just wondering if this little tweak (using the "extra" front speaker posts to bi-amp) would make a difference with my 602 S3's and my 861, and/or if it made more sense to perhaps upgrade to the 805 and try it. I enjoy the discussion.

 

[Seth=L]

Didn't we go over all of this once with J_neutron after I started a thread about bi-wiring?

I will submit to you that Bi-wiring or passive bi-amping can make a difference, but, for the average listening (99.9%) it may not be noticeable. I tried it once (when I thought it would make a difference) and I didn't notice a difference (but this was long before I knew jack about audio). There are many other things that affect the audio more so than bi-amping, bi-wiring, passive bi-amping (but I suppose this upgrades cost next to nothing if you don't buy "danceable cables").

Said my final piece.

 

[PENG]

Didn't we go over all of this once with J_neutron after I started a thread about bi-wiring?

I will submit to you that Bi-wiring or passive bi-amping can make a difference, but, for the average listening (99.9%) it may not be noticeable. I tried it once (when I thought it would make a difference) and I didn't notice a difference (but this was long before I knew jack about audio). There are many other things that affect the audio more so than bi-amping, bi-wiring, passive bi-amping (but I suppose this upgrades cost next to nothing if you don't buy "danceable cables"

Said my final piece.

jneutron did try to use some simple math (Binomial expansion if I remember right) to show that there is a difference electrically. By the way, I agree with everything you said, this time. Edit: the maths may not be in the thread you started, there are too many of those threads..

 

[rnatalli]

I've tried bi-wiring before, didn't notice anything. I also tried passive bi-amping using my LPA-1 tonight:

http://forums.audioholics.com/forums/showthread.php?t=40460

Still haven't noticed anything. Haven't tried using two separate amplifiers.

 

[PENG]

My background is located here:
http://www.audioholics.com/Members/Gene/biography-1

I have had my hand in amplifier design for nearly 7 years prior to quitting my cubicle engineering job to pursue the dream of Audioholics full time.

As for your comments about biwiring:
I find it a little hard to swallow since the combined signal folds back to a common amplifier and thus the amp has to deal with the back EMF regardless. In any event, biwiring looks cool, it lowers the effective gauge and is a cheap tweak provided you don't purchase expensive esoteric cable

I recommend reading this article on speaker cable gauge:
http://www.audioholics.com/education/cables/speaker-cable-gauge

and we do have a series of articles about bi-wiring you may wish to check out:
http://www.audioholics.com/education/cables/bi-wiring-from-amplifier-to-loudspeaker

Thanks for the links, I read them before, and I never have any doubt about your AV knowledge. I do have problem with the article in your 2nd link.

As expected, we agree on the bi-amp part, but not the biwire part. The gap is not big though, all along I have been saying that biwiring make a difference electrically. In terms of audible difference, some reputable speaker manufacturers insist the difference is audible but I tried and could not hear such difference. Even when I say electrcially, I agree with you that "the combined signal folds back to a common amplifier and thus the amp has to deal with the back EMF regardless". But I know I am right about the fact that the frequency spectrums of the signals in each of the cable pair are different so electrically speaking, biwiring is not the same as using thicker cable. You don't have to agree or believe, but you wish I am confident that you could use a spectrum analyzer to see the difference.