How does the sound quality compare between Yamaha RX-Z1 and Outlaw 975?

[sharkman]

Those aren't the limits, those are benchmark measurements.

 

[AcuDefTechGuy]

Those aren't the limits, those are benchmark measurements.

Above 1% THD, the amp will start to clip. So clipping is not a limit to you?

You want to know if the amp can go to 2% THD? You want to listen to music @ 2% THD?

So what is the limit to any amp if it's not their clipping point?

 

[RichB]

Above 1% THD, the amp will start to clip. So clipping is not a limit to you?

You want to know if the amp can go to 2% THD?

Those are not the same metrics.
i would argue they should be though.
If an amp is not capable of providing the power needed for a musical peak, it limits power.
Limited power means limited peak which is a form of compression.

There are soft clipping circuits and limiters in some designs.
For example, ATI (and some class-d designs) have limiters. ATI has implemented 3% max distortion circuits.
Such a design must limit the power when it cannot be provided without excess distortion.
if this is a short musical peak, the listener may be unaware that the volume has been limited.

- Rich

 

[PENG]

Those aren't the limits, those are benchmark measurements.

Benchmarks are figures for people to measure against/compare with. We can agree or disagree on whether 0.1% THD or lower should be considered as benchmarks for whatever reasons but they are benchmarks none the less. People could prefer a lower or higher benchmarks for their own reasons. I prefer 0.01% for THD+noise as a good benchmark, for my own reasons. That's why I need to see the graph so I can pick the output level at 0.01% as what I would consider the power output limit of the amp under test.

I assume the numbers he quoted were from actual lab measurements, so I would think they are in fact limits. Again obviously we can agree or disagree with whether the limits should be the output into X ohm at Y phase angle, at 1 kHz or for the whole 20 to 20 kHz bandwith at 1%, 0.1% or lower but those numbers are in fact limits of the amp under test, for those who agree with the test conditions being acceptable to them.

 

[PENG]

Those are not the same metrics.
i would argue they should be though.
If an amp is not capable of providing the power needed for a musical peak, it limits power.
Limited power means limited peak which is a form of compression.

There are soft clipping circuits and limiters in some designs.
For example, ATI (and some class-d designs) have limiters. ATI has implemented 3% max distortion circuits.
Such a design must limit the power when it cannot be provided without excess distortion.
if this is a short musical peak, the listener may be unaware that the volume has been limited.

- Rich

I am not understanding you point. ADTG is quoting a power level when the distortion is at a certain %. The assumption is that when THD+N is as high as 1%, clipping must be taking place. We can debate at what % we consider clipping is really taking place. I prefer that to be 0.01% but that's just me.

If say the amp under test reached 1% or 0.1% if you prefer (again for me I pick 0.01%) distortion at 100W then I do not believe the amp would be compressing at that point as there is no need for it to. I could be wrong but I think you might have read something about compression without fully understanding what the author might be trying to say, and end up worrying about something too much. Your last paragraph though, would indicate that you do understand and we maybe saying more or less the same thing. Interesting!

 

[AcuDefTechGuy]

It seems a lot more fun talking about buying high quality Parasound and ATI amps.

Everyone should just get one or two and be happy.

 

[RichB]

I am not understanding you point. ADTG is quoting a power level when the distortion is at a certain %. The assumption is that when THD+N is as high as 1%, clipping must be taking place. We can debate at what % we consider clipping is really taking place. I prefer that to be 0.01% but that's just me.

I am saying that, at least theoretically, an amp could be designed with a limiter set so it never delivers more than 1% distortion. In such a design, distortion will no be heard. Compression will occur, but also will not he heard

If say the amp under test reached 1% or 0.1% if you prefer (again for me I pick 0.01%) distortion at 100W then I do not believe the amp would be compressing at that point as there is no need for it to. I could be wrong but I think you might have read something about compression without fully understanding what the author might be trying to say, and end up worrying about something too much. Your last paragraph though, would indicate that you do understand and we maybe saying more or less the same thing. Interesting!

I am not overly concerned that a well designed amp will compress rated for 100 watts will compress sound for a peak <= 100 watts. However, at impedance X and phase Y, some amps may not deliver the full 100 watts quoted by their specification.
I think we are talking about the same thing, but since you are more knowledgeable than I, I'll let you decide

- Rich

 

[Irvrobinson]

I am saying that, at least theoretically, an amp could be designed with a limiter set so it never delivers more than 1% distortion. In such a design, distortion will no be heard. Compression will occur, but also will not he heard

I have an amp like that, an ATI AT602, and it has limiting circuitry. I believe I have hit the limiters when testing it briefly with my primary system, and I'm convinced the compression is audible when I'm trying to make it audible. For at least 95% of my listening time though I'm pretty sure I wouldn't hear any difference between the AT602 and my usual AT3000. I haven't done any long-term listening however; it was only for an hour or so (and required ugly XLR-to-RCA adapters).

 

[AcuDefTechGuy]

For at least 95% of my listening time though I'm pretty sure I wouldn't hear any difference between the AT602 and my usual AT3000.

That's what I call "quality amp" right there.

Not many 60WPC amp could brag about being stable down to 1 ohm (The Audio Critic power-cube) and can power the Salon2 for at least 95% (correction, make that 99.5%) of the time.

 

[PENG]

I am saying that, at least theoretically, an amp could be designed with a limiter set so it never delivers more than 1% distortion. In such a design, distortion will no be heard. Compression will occur, but also will not he heard



I am not overly concerned that a well designed amp will compress rated for 100 watts will compress sound for a peak <= 100 watts. However, at impedance X and phase Y, some amps may not deliver the full 100 watts quoted by their specification.
I think we are talking about the same thing, but since you are more knowledgeable than I, I'll let you decide

- Rich

Sorry about the partial misunderstanding earlier, yes we are basically saying the same. With well designed soft clipping/limiter one may not hear distortion but compression when the amp's power limit is exceeded but that should not happen as long as the amp is working within its limit. I know my amps will always be within their limits because I measured their outputs with both voltage and current meters before. Even at well above my ear's limit the amps will only be cruising at 10 to 20% of their rated output during peaks. OMMV.

 

[PENG]

It seems a lot more fun talking about buying high quality Parasound and ATI amps.

Everyone should just get one or two and be happy.

Thanks for including the Parasound so I guess I can be happy too right?

 

[Irvrobinson]

That's what I call "quality amp" right there.

Not many 60WPC amp could brag about being stable down to 1 ohm (The Audio Critic power-cube) and can power the Salon2 for at least 95% of the time.

Yeah, I'm impressed with the AT602. And perhaps that 95% estimate was a bit overstated, I probably listen to well-recorded fusion jazz at realistic volumes twice per week. With classical music, classic rock, or small jazz ensembles I think the estimate is more like 99.5% The 0.5% being some Telarc blockbusters. But for the Yellowjackets I'd want the AT3000 (and the sub turned on). Since my primary system is for music only I don't have the action movie problem to contend with.

 

[AcuDefTechGuy]

Thanks for including the Parasound so I guess I can be happy too right?

Absolutely.

Of course, I mean a lot more amps than that, but that requires a lot more typing.

McIntosh, Mark Levinson, Krell, Bryston, Anthem, Classe..... geez, I'm already tired.

 

[PENG]

Absolutely.

Of course, I mean a lot more amps than that, but that requires a lot more typing.

McIntosh, Mark Levinson, Krell, Bryston, Anthem, Classe..... geez, I'm already tired.

You can stop typing now as you just added two more brands I also have, wish you have included Marantz though....but that's okay you have done enough.

 

[AcuDefTechGuy]

You can stop typing now as you just added two more brands I also have, wish you have included Marantz though....but that's okay you have done enough.

Goodness. So you are 3 times happy.

 

[Tidan]

Since we are off-topic What would you guys recommend for a surge protector for my new 975/7125 combo? I also have: satellite box; LCD TV; DVD player; bluray; HTPC; sub-amp; sub-EQ.

 

[PENG]

Since we are off-topic What would you guys recommend for a surge protector for my new 975/7125 combo? I also have: satellite box; LCD TV; DVD player; bluray; HTPC; sub-amp; sub-EQ.

Good ones cost a fortune. I don't use them but I pull the plug during electrical storms.

 

[Irvrobinson]

I pull the plug during electrical storms.

That's what I do too.

 

[Tidan]

We sometimes get unexpected blackouts due to santa anna's (or simply SDGE's whimsicle nature). If your were to use one, would it have 'line-cleaning' features or just plain ole surge protection?
Looking at several from monoprice and newegg but there are just so damn many I can't decide what I even want.

 

[RichB]

We sometimes get unexpected blackouts due to santa anna's (or simply SDGE's whimsicle nature). If your were to use one, would it have 'line-cleaning' features or just plain ole surge protection?
Looking at several from monoprice and newegg but there are just so damn many I can't decide what I even want.

I don't use one even though I have a Panamax 5400.
It has a dedicated amp outlet but all amps that I have plugged into it (Parasound A21, ATI3500, Outlaw 7500) reduced the sound quality.

I have installed a whole house surge protector on the breaker panel.
I am going install another 20 amp line on a dual breaker to attempt to tame ground loops issues.

- Rich