Going to an AVR Preamp. Diehard 2chan guy

[PENG]

Okay I got a little carried away with frustration. It's not easy keeping up with all the terminology and Technical knowledge that you guys have over most of us in here. So I sorry, So Monoblock amps are the why to go right? I mean, why would anyone want to bi-amp a pair of speaker's? When all you would really need is for each speaker to have it's on power supply. Wouldn't that be a better solution than just removing the jumpers. I read this all the time someone adds a multi channel amp and the first thing is, man I can use 4 channels to Bi-amp my L/R mains, use the amps in my 'AVR' everyone should know when they look at the rail it's One Rail! on most, 'AVR''s unless your up the food chain with some mid to entry-level Flagships, than you get symmetrical design like Yamahas than you have Onkyos famous block design.v There isn't a bunch of Amps in a AVR! So back to Bi-amping speaker's, without removing the crossover in each speaker and without adding a EQ between pre-amp and amp. Removing just the jumpers isn't Bi-amping. I'm going look at eMatthews L/R mains again with the nice Sub, and his Really nice ATi amp made by them dudes in California.

There are many fake facts on the internet regarding bi-amping. AH has many lengthy threads and articles on the topic but to save you time, let me recap a few bullet points below for you.

• Removing just the jumpers at the speakers, using the same multi channel amplifiers or monblocks will allow you do implement the passive bi-amp scheme.
• Removing the jumpers as well as the passive crossovers, and use multi channel or monoblock amps, plus external active crossovers, will allow you to implement the active bi-amp scheme.

Advantages (most likely without audible improvements even if done right) of passive bi-amp

• The theory is that by separating (but not removing) crossover network into 2 parts, would result in much reduced interference from the typically much higher LF/MF signal currents on the much lower HF signal.
• Again, in theory, the back (or counter) emf (electromotive force) effects from the woofer (s) on the HF signal will be much lower in the passive bi-amp scheme.
• Easy to do.

There are other claimed benefits, but the two above are easily verified to be factual, by any EE or others who know the relevant electromagnetic and circuit theories. On certain websites, you will see counter arguments that are most likely based on the presenters limited knowledge of the applicable electrical theories. Having said that, it seems widely accepted on this forum that the two factual points I listed above would not result in audible improvements, and people often cited that passive bi-amp is a waste of time and money. Regardless, the theory is sound. So for those interested, there is no harm trying, to find out if there are audible benefits for your own system.

Advantages (with audible effects) of active bi-amp

• The user has controls of the crossover points, slopes, impedance, and phase shifts.
• Reduced, if not eliminated phase related issues.
• Reduced losses (insertion loss due to the passive crossovers).

Obviously the above are not exhaustive, there are other benefits that one can come up with, but I believe even the 3 bullets above are significant enough for people to implement active bi-amp schemes. The trick is, like anything thing else, you have to know what you are doing otherwise you may make things worse.

Edit: The intents of this post is to recap the theoretical benefits of active and passive bi-amp schemes only. Whether such benefits or advantages would result in audible improvements in SQ, I do not have a firm opinion. As such, I edited a few things to reflect the same.

 

[PENG]

But who's going to hear the difference between a SNR of 110dBA vs 118dBA vs 128dBA?

Still very insignificant, but the Denon actually has lower THD than both of these very high-end Pre-pros.

My guess is, eargiant in an anechoic chamber. armors on

 

[AcuDefTechGuy]

My guess is, eargiant in an anechoic chamber. armors on

Even if he has golden ears and could hear the difference between a SNR of 110dB vs 118dB, I think even he would agree that most ordinary people do not have golden ears and will not be able to discern.

Shucks, I could hear the difference between a THD of 0.004% (Denon) vs 0.02% (Audio-Control). No wonder the $1,000 Denon AVR sounds better than the $9,000 Audio-Control Pre-pro.

 

[TechHDS]

There are many fake facts on the internet regarding bi-amping. AH has many lengthy threads and articles on the topic but to save you time, let me recap a few bullet points below for you.

• Removing just the jumpers at the speakers, using the same multi channel amplifiers or monblocks will allow you do implement the passive bi-amp scheme.
• Removing the jumpers as well as the passive crossovers, and use multi channel or monoblock amps, plus external active crossovers, will allow you to implement the active bi-amp scheme.

Advantages (most likely without audible improvements even if done right) of passive bi-amp

• The theory is that by separating (but not removing) crossover network into 2 parts, would result in much reduced interference from the typically much higher LF/MF signal currents on the much lower HF signal.
• Again, in theory, the back (or counter) emf (electromotive force) effects from the woofer (s) on the HF signal will be much lower in the passive bi-amp scheme.
• Easy to do.

There are other claimed benefits, but the two above are easily verified to be factual, by any EE or others who know the relevant electromagnetic and circuit theories. On certain websites, you will counter arguments that are most likely based on the presenters limited knowledge of the applicable electrical theories. Having said that, it is generally (me too) accepted that the two factual points I listed above would not result in audible effects, and most people believe passive bi-amp is a waste of time and money.

Advantages (with audible effects) of active bi-amp

• The user has controls of the crossover points, slopes, impedance, and phase shifts.
• Reduced, if not eliminated phase related issues.
• Reduced losses (insertion loss due to the passive crossovers).

Obviously the above are not exhaustive, there are other benefits that one can come up with, but I believe even the 3 bullets above are significant enough for people to implement active bi-amp schemes. The trick is, like anything thing else, you have to know what you are doing otherwise you may make things worse.

Thx, will pull up those articles. I always knew about the bi-amp thing with just removing the jumpers isn't worth the time or expense. Learned that hassle back in the 80s early. Also doing it the right way #1. can get expensive and #2. if you don't know what your doing yeah, fry one or more of your driver's.

 

[AcuDefTechGuy]

I have spent some effort to determine that the RX-A820 AVR amp level matched to the ATI AT522H both using under 10 watts in SBT's do sound different.

The Yamaha-820's SNR is probably about 105dB vs 120dB-123dB on the ATI and Oppo.

I suppose some people (<Eargiant) could make a case of 105dB vs 120dB SNR.

The Yamaha might be using a lot more than 10W, especially at 4 ohms and below!

The Revel M20 dips to 4 ohms and below (70Hz - 3kHz). That lowly Yamaha isn't great at 4 ohms at all. Even if it could muster enough wattage, the 4-ohm load is probably taxing the heck out of the Yamaha. OTOH, the ATI Amp can handle 1-ohm loads in its sleep.

So it's not just the power output, but I think how much stress the Yamaha is with 3 - 4 ohm impedance.

 

[AcuDefTechGuy]

Thx, will pull up those articles. I always knew about the bi-amp thing with just removing the jumpers isn't worth the time or expense. Learned that hassle back in the 80s early. Also doing it the right way #1. can get expensive and #2. if you don't know what your doing yeah, fry one or more of your driver's.

I definitely agree that passive bi-amp is an unequivocal waste of time.

But even with active bi-amp, I think only the bass gets the real benefit since the midrange and treble don't require that much power.

 

[PENG]

I definitely agree that passive bi-amp is an unequivocal waste of time.

But even with active bi-amp, I think only the bass gets the real benefit since the midrange and treble don't require that much power.

I think if done well, it could help smoothing the FR, minimize resonances and other unintentional nasty effects often associated with not perfectly designed passive crossovers. However, purist may not like the introduction of DSPs, they don't even want REQ, Audyssey, Dirac or whatever right?

 

[PENG]

The Yamaha-820's SNR is probably about 105dB vs 120dB-123dB on the ATI and Oppo.

I suppose some people (<Eargiant) could make a case of 105dB vs 120dB SNR.

The Yamaha might be using a lot more than 10W, especially at 4 ohms and below!

The Revel M20 dips to 4 ohms and below (70Hz - 3kHz). That lowly Yamaha isn't great at 4 ohms at all. Even if it could muster enough wattage, the 4-ohm load is probably taxing the heck out of the Yamaha. OTOH, the ATI Amp can handle 1-ohm loads in its sleep.

So it's not just the power output, but I think how much stress the Yamaha is with 3 - 4 ohm impedance.

My concern with the power capability of the Yamaha when trying to deliver 10 W average is the peaks. A 15 dB peak would bring the output requirements to 320 W. At that point RichB may be able to hear the distortions from clipping, though that depends on music contents. Not too many tracks would have recurrent peaks that high and frequent/repetitive enough to be detected by ordinary humans.

The ATI may be only 3 to 5 dB more capable than the Yamaha, but that's enough for it to not clip at the 320 or even 600 W levels for short duration.

 

[RichB]

There are many fake facts on the internet regarding bi-amping. AH has many lengthy threads and articles on the topic but to save you time, let me recap a few bullet points below for you.

• Removing just the jumpers at the speakers, using the same multi channel amplifiers or monblocks will allow you do implement the passive bi-amp scheme.
• Removing the jumpers as well as the passive crossovers, and use multi channel or monoblock amps, plus external active crossovers, will allow you to implement the active bi-amp scheme.

Advantages (most likely without audible improvements even if done right) of passive bi-amp

• The theory is that by separating (but not removing) crossover network into 2 parts, would result in much reduced interference from the typically much higher LF/MF signal currents on the much lower HF signal.
• Again, in theory, the back (or counter) emf (electromotive force) effects from the woofer (s) on the HF signal will be much lower in the passive bi-amp scheme.
• Easy to do.

There are other claimed benefits, but the two above are easily verified to be factual, by any EE or others who know the relevant electromagnetic and circuit theories. On certain websites, you will counter arguments that are most likely based on the presenters limited knowledge of the applicable electrical theories. Having said that, it is generally (me too) accepted that the two factual points I listed above would not result in audible effects, and most people believe passive bi-amp is a waste of time and money.

Advantages (with audible effects) of active bi-amp

• The user has controls of the crossover points, slopes, impedance, and phase shifts.
• Reduced, if not eliminated phase related issues.
• Reduced losses (insertion loss due to the passive crossovers).

Obviously the above are not exhaustive, there are other benefits that one can come up with, but I believe even the 3 bullets above are significant enough for people to implement active bi-amp schemes. The trick is, like anything thing else, you have to know what you are doing otherwise you may make things worse.

Arimm (What's best forum) measured an AVR with the woofer amp clipping which showed the amp driving the upper end was not clipping. The point has been made recently that the RX-A820 must be carefully compared to a separate amp because of clipping.

Gene's review of the Monoprice Monolith amps made the point that you could buy a 7-channel and use the extra channels to bi-amp. I don't think he is known for making frivolous recommendations.

For cripes sake folks, you can try this at home with a single speaker and stacking banana plugs. If you hear a benefit do it, if you don't that's fine too. I don't understand the impulse to dissuade other from trying bi-amping and making up their own mind.

The rarefied upper end community does not like multi-channel amps and bi-amping. They like 90K boulder amps on stands. Before I ever did anything like that, I would bi-amp with an ATI AT6000. If you like monoblocks, consider bridging Benchmark AHB2's. I have heard them, they sound great.

- Rich

 

[RichB]

My concern with the power capability of the Yamaha when trying to deliver 10 W average is the peaks. A 15 dB peak would bring the output requirements to 320 W. At that point RichB may be able to hear the distortions from clipping, though that depends on music contents. Not too many tracks would have recurrent peaks that high and frequent/repetitive enough to be detected by ordinary humans.

The ATI may be only 3 to 5 dB more capable than the Yamaha, but that's enough for it to not clip at the 320 or even 600 W levels for short duration.

I don't know where you are getting these numbers.
Here are the measurements where the Oppo BDP-105D is supplying volume control on its two sets of analog outs. My listening is at volume 33 on the Oppo (0 to 100 scale).
The measurements below show are at about 2.7 volts RMS.

I picked the lowest impedance measured my Sterephile as the worst case. Even then, RMS is 2 watts. Double that, and you have 4 watts.

Unless I am missing something, at this voume level you cannot get to 10 watts with the M2's.There is no way that the RX-A820 rated at 100WPC 20Hz to 20kHz is clipping but it has inferior sound quality (SBT in my and a friends estimation).

The case under test has the following connection paths:

BDP-105D -> XLR -> AT522NC -> M20's
BDP-105D -> RCA -> Yamaha RX-A820 (Pure Direct) -> M20's.

Although the Yamaha is in pure direct mode, it is still an is adding preamplification (volume control and all related circuitry) in addition to amplification. There is no way to eliminate this.
It is not entirely an amp comparisson but it is a comparission between the two connectivity choices with those speakers. The low power levels were chosen specifically to remove clipping from the equation.

IMO, regardless of the power and SNR's, there is reason to believe that separates, in this case, simply using a BDP-105D (or DAC with Volume control) can provide better sound quality. That does not mean that other AVRs and speakers may show no discernable difference. The possibility of an improvement exists and cannot always be quatified by googling specifications.

That is the case I am making that directly addresses the OP.

Amen.

- Rich

 

[PENG]

I don't know where you are getting these numbers.
Here are the measurements where the Oppo BDP-105D is supplying volume control on its two sets of analog outs. My listening is at volume 33 on the Oppo (0 to 100 scale).
The measurements below show are at about 2.7 volts RMS.

Hey Rich, I did read all your posts, and the 10 W came from:

"I have spent some effort to determine that the RX-A820 AVR amp level matched to the ATI AT522H both using under 10 watts in SBT's do sound different. "

Now that I have re-read that post, I realized I miss the key word "under". You did a good job detailing everything, it's my fault that I didn't pay attention to the details.

I thought the 2.7V was used to level match only, so as to determine the corresponding volume positions of the OPP and AVR. Now I realize it was the actual Vrms measured during the comparison. In that case, none of my power related comments do not apply, and whatever differences you are getting are not due to the weaker amp section of the Yamaha.

My apology for misreading your post#104.

 

[PENG]

Arimm (What's best forum) measured an AVR with the woofer amp clipping which showed the amp driving the upper end was not clipping. The point has been made recently that the RX-A820 must be carefully compared to a separate amp because of clipping.

That is possible and we can assume it was in fact the case for that forum memeber. Just one cautionary point though, just because the amp clipped in the non bi-amp configuration, it does not mean the tweeter signal would be clipping also. Remember, a non-sinusoidal music waveform can be represented by an infinite series of sine waves. If you do a Fourier transform, it may show the higher frequencies are not affected by the flat top, if that flat top is due to some parts/frequencies of the LF signal clipping.

Gene's review of the Monoprice Monolith amps made the point that you could buy a 7-channel and use the extra channels to bi-amp. I don't think he is known for making frivolous recommendations.

Was he not talking about active bi-amping? I don't think anyone would dispute the potentially audible sound quality improvements of active bi-amping.

For cripes sake folks, you can try this at home with a single speaker and stacking banana plugs. If you hear a benefit do it, if you don't that's fine too. I don't understand the impulse to dissuade other from trying bi-amping and making up their own mind.

I agree, I have even tried bi-wire. I actually believe that there could be audible improvements in some cases, even in passive biamp schemes. It is however, a fact that many people on this and other forums do not buy it, and many would not hesitate to call it a waste of time. So I included that notion in anticipation..

 

[RichB]

Hey Rich, I did read all your posts, and the 10 W came from:

"I have spent some effort to determine that the RX-A820 AVR amp level matched to the ATI AT522H both using under 10 watts in SBT's do sound different. "

Now that I have re-read that post, I realized I miss the key word "under". You did a good job detailing everything, it's my fault that I didn't pay attention to the details.

I thought the 2.7V was used to level match only, so as to determine the corresponding volume positions of the OPP and AVR. Now I realize it was the actual Vrms measured during the comparison. In that case, none of my power related comments do not apply, and whatever differences you are getting are not due to the weaker amp section of the Yamaha.

My apology for misreading your post#104.

No problem. You are more knowledgable than I, so I spend a lot of time trying to figure out what I got wrong. Thanks for clarifying.

- Rich

 

[M Code]

I don't know where you are getting these numbers.
Here are the measurements where the Oppo BDP-105D is supplying volume control on its two sets of analog outs. My listening is at volume 33 on the Oppo (0 to 100 scale).
The measurements below show are at about 2.7 volts RMS.

View attachment 23820

I picked the lowest impedance measured my Sterephile as the worst case. Even then, RMS is 2 watts. Double that, and you have 4 watts.

Unless I am missing something, at this voume level you cannot get to 10 watts with the M2's.There is no way that the RX-A820 rated at 100WPC 20Hz to 20kHz is clipping but it has inferior sound quality (SBT in my and a friends estimation).

The case under test has the following connection paths:

BDP-105D -> XLR -> AT522NC -> M20's
BDP-105D -> RCA -> Yamaha RX-A820 (Pure Direct) -> M20's.

Although the Yamaha is in pure direct mode, it is still an is adding preamplification (volume control and all related circuitry) in addition to amplification. There is no way to eliminate this.
It is not entirely an amp comparisson but it is a comparission between the two connectivity choices with those speakers. The low power levels were chosen specifically to remove clipping from the equation.

IMO, regardless of the power and SNR's, there is reason to believe that separates, in this case, simply using a BDP-105D (or DAC with Volume control) can provide better sound quality. That does not mean that other AVRs and speakers may show no discernable difference. The possibility of an improvement exists and cannot always be quatified by googling specifications.

That is the case I am making that directly addresses the OP.

Amen.

- Rich

What position was the Speaker Impedance Mode set for the 820??

Just my $0.02...

 

[RichB]

What position was the Speaker Impedance Mode set for the 820??

Just my $0.02...

It's at the 6 ohm, the 4 ohms is a real disaster.

- Rich

 

[RichB]

Was he not talking about active bi-amping? I don't think anyone would dispute the potentially audible sound quality improvements of active bi-amping.

I believe AH was one of the first to find benefit in AVR bi-amp setting, found an improvement and is credited for the proliferation of this feature in AVRs. AVRs do not support active bi-amping.

Just because active, when well implemented, can be better does not mean the good old passive bi-amping has no value.

Honestly, it's a pain to keep making the same point, knowing full-well the accolades that would be showed upon me for taking the opposing position.

For the record, Veocks recommends against bi-wiring and even worse, using different gauge wires for the upper and lower sections.

- Rich

 

[PENG]

I believe AH was one of the first to find benefit in AVR bi-amp setting, found an improvement and is credited for the proliferation of this feature in AVRs. AVRs do not support active bi-amping.

Just because active, when well implemented, can be better does not mean the good old passive bi-amping has no value.

Honestly, it's a pain to keep making the same point, knowing full-well the accolades that would be showed upon me for taking the opposing position.

For the record, Veocks recommends against bi-wiring and even worse, using different gauge wires for the upper and lower sections.

- Rich

Honestly, I felt the pain too, and I have tried to remain neutral and open minded on this very issue over the years.

 

[RichB]

Advantages (most likely without audible improvements even if done right) of passive bi-amp

• The theory is that by separating (but not removing) crossover network into 2 parts, would result in much reduced interference from the typically much higher LF/MF signal currents on the much lower HF signal.
• Again, in theory, the back (or counter) emf (electromotive force) effects from the woofer (s) on the HF signal will be much lower in the passive bi-amp scheme.
• Easy to do.

There are other claimed benefits, but the two above are easily verified to be factual, by any EE or others who know the relevant electromagnetic and circuit theories. On certain websites, you will counter arguments that are most likely based on the presenters limited knowledge of the applicable electrical theories. Having said that, it is generally (me too) accepted that the two factual points I listed above would not result in audible effects, and most people believe passive bi-amp is a waste of time and money.

PENG of post 121 , I like to intruduce you to PENG of post 137

Honestly, I felt the pain too, and I have tried to remain neutral and open minded on this very issue over the years.

- Rich

 

[PENG]

PENG of post 121 , I like to intruduce you to PENG of post 137



- Rich

As I said, I tried to remain neutral so I cited the theoretical advantages but reflected on being skeptical about whether the advantages would translate into audible improvements. Based on posts on this and other forums, I believe most people don't believe in the benefits, but I should have it worded it in a more balanced/neutral fashion. Thank you for pointing this out, I'll see if it can be edited.

 

[Pogre]

Your pretty much spot on, eMatthews thread got derailed some and he seems to be rolling with it, good guy in my book. Those analogies, of 'integrated AVR, AVR pre' thats used when someone with this hobby can not afford to do separates or just doesn't want to spend the money and use there Avr, 'pre-amp' and add a amp..so they say I will use my AVR like a pre-pro, you would be surprise how many really don't know much about this hobby that most of us take for granted. My setup is modest at best and when people come over they look at it first and one of the first question is man, that must have cost a lot of money like what 10 grand? I just smile and chuckle a little. Could you imagine if someone with very little to no experience with this hobby looked upon a really high-end system? They would think it was from aliens. Try explaining the technical side to someone like that they look at you like you just lot your mind or something. Meaning they could care less and walk off. I can just about read their mind just by reading the look on their face, like he spent 3,000 on that? They go, My used Car cost that much and they walk off could care less.

I get that a lot. My friends think I'm nuts, lol.