[germanium]

Quote:

if the ceramic was C0G/NP0 formulation then even on the "audiophile" cap criteria of dielectric absorption the silver mica is likely measurably worse - really should read Bateman, Pease, Hofer on Capacitor "quality" - not just 25-30 yr old Jung/Curl articles

Note that the GFA555 amp from adcom used the silver mica cap in that location. The GFA555 is the next model up from the GFA545 & lacked the grainy sound of the GFA545. I discovered this after trying various caps in that location & settled on the silver mica before I found that the GFA 555 used silver mica cap. Silver mica is not a audiophile cap but they are much higher quality than most all ceramics. Still you have to use what works best in the circuit in question. The highest qualty by most peoples opinion may not be the best in a particulr circuit. It is still cut & try to get best results. 

 

[bigshot]

How can bass be weaker, if the bass is equally represented in the frequency response? 

That is a much nicer way of saying it than the way I was going to. I doubt you'll get a satisfactory response.

 

[germanium]

Quote:

That is a much nicer way of saying it than the way I was going to. I doubt you'll get a satisfactory response.

While I can't really explane why all the mods I've done seem to improve appearant frequency response without actually changing measured frequency response. Bob Carver figured out how to characterize it without resorting to graphs. It's called tranfer function. Truth is you cannot as yet characterize what an amp will sound like by looking at graphs or specs. There are still things that designers can do to alter the sound that is unseen in graphs & specs. CD players can still sound different even if they measure identically. I have heard quite radical differences in older players but even newer ones though more subtle still have differences. Take the best of the best & mod the power supply & you will get a true wake up call as they will sound different without showing in the specs at all. None of my CD player mods has ever altered the measured frquency response yet they all sounded quite different when the power supply was modded. Bear in mind that the power supply in most cases is in the direct signal path.

 

[germanium]

Quote:

Lee - I agree to an extent. But there is harm in propogating falsehoods. Persistent mythology costs real money, and damages the credibility of the field. Truth matters. And we are dealing with claims which can be tested. When people ignore objective data in order to maintain a position, it is irrational, and in the long run, hurts all of us. 

Persistant mythology may be whats needed to get this economy working again. Someones got to start putting people to work. If it's creating what many feel to be nonexistant improvements so be it. I happen not to 100% feel that way as I have done enough experimentation to satisfy myself that differences can be heard that are real differences & understand the reasons why. Yes there are some charletans out there but there are also reputable manufacturers that have done massive testing with trained listeners that know what to listen for & could with reasonable assurance seperate them out in blind testing as that is how they are in fact trained & must be at least 80% accurate in thier identification in order too be on the listener panel. Harmon Kardon has such a panel.

 

[BlindInOneEar]

Have you tried Harman's "How to Listen" app?  It's actually pretty interesting to play with.  http://harmanhowtolisten.blogspot.com/
 

 

[chris719]

Has anyone found distortion measurements comparing PPS to C0G/NP0?

 

[bigshot]

While I can't really explane why all the mods I've done seem to improve appearant frequency response without actually changing measured frequency response.

OK. I'll say it... I don't think you measured the frequency response before and after your tweaks. I think you're just saying that to make your point. I doubt if there was any audible difference at all. But even if there was a difference, enough time would have passed that you wouldn't be able to remember exactly what it originally sounded like anyway, and there would be no way to level match or do a direct A/B comparison. The only way to really know if there was an improvement is if you had two identical amps- one with the mod, one stock- and directly compared them.

 

[germanium]

Quote:

OK. I'll say it... I don't think you measured the frequency response before and after your tweaks. I think you're just saying that to make your point. I doubt if there was any audible difference at all. But even if there was a difference, enough time would have passed that you wouldn't be able to remember exactly what it originally sounded like anyway, and there would be no way to level match or do a direct A/B comparison. The only way to really know if there was an improvement is if you had two identical amps- one with the mod, one stock- and directly compared them.

As a matter of fact I did as well as distortion both before & after & no measurable difference.Sound is both clearer & better bass no matter the volume. I'm going to make this my last post in this thread as it is mostly a pointless thread anyway not that the original poster asked a pointless question but that a fair amount of the thread is both off target & highly opinionated as to what is in fact audible & it seems that some  can't even fathom that someone can actually hear a difference as well as others when standard measurements don't show any difference. Note; I said standard measurements.

 

[bigshot]

See:
Line level matched
A/B comparison
Auditory memory

 

[drez]

Quote:

How can bass be weaker, if the bass is equally represented in the frequency response? 
 

 
The sound of equipment often has nothing to do with frequency response, my best bet is it is to do with temporal performance - as manifest in such characteristics such as impact and decay.  If you want to witness the impact a power supply can have on an amplifier the easiest test is to load the [power] cable with a large ferrite, or use a 25 meter heavy duty extension cable coiled up on itself and I can [almost] guarantee you will hear a difference against a sensibly specced cable.
 
Distortion by itself is a fairly mute specificatoin, IMO it depends on the nature of the distortion.

 

[JadeEast]

Quote:

...off target & highly opinionated as to what is in fact audible & it seems that some  can't even fathom that someone can actually hear a difference as well as others when standard measurements don't show any difference. Note; I said standard measurements.

Dogmatic subjectivists fall into solipsism believing what they perceive not only correlates but determines what is true; Dogmatic objectivists claim providence over truth and collapse all meaning to that which can be quantifiably measured.
 
I don't have an answer but it seems that issues like cables and capacitors point towards deeper conflicts about the nature of the world, truth, perception, and consciousness.

 

[OJNeg]

Quote:

Dogmatic subjectivists fall into solipsism believing what they perceive not only correlates but determines what is true; Dogmatic objectivists claim providence over truth and collapse all meaning to that which can be quantifiably measured.
 
I don't have an answer but it seems that issues like cables and capacitors point towards deeper conflicts about the nature of the world, truth, perception, and consciousness.

 
Mind = Blown

 

[mike1127]

Quote:

Dogmatic subjectivists fall into solipsism believing what they perceive not only correlates but determines what is true; Dogmatic objectivists claim providence over truth and collapse all meaning to that which can be quantifiably measured.
 
I don't have an answer but it seems that issues like cables and capacitors point towards deeper conflicts about the nature of the world, truth, perception, and consciousness.

They certainly reveal differences in epistemology between "camps"; and for those who don't know what "epistemology" means, I guarantee you have one. Most people just don't articulate it.

 

[mike1127]

Quote:

Hey mike! I'm still curious to know if you feel you have ever heard a good working example of this "whole system" you are talking about.
People have been known to chase mirages, or imaginary pots of gold at the end of the rainbow, with not so great results -- any chance you might be doing something like that?

Everyone uses the "whole system." Audio exists only to be heard, so it eventually passes through an entire chain from microphone to headphone/speaker.
 
I don't really know what you mean by "chase mirages."
 
Sheffield Lab is a recording studio that uses a philosophy like this. Actually, just about any audiophile label would. I discovered a label called "Albany Records;" heard their recording of a trombone quartet. Fantastic, and almost certainly they put an emphasis on listening as the only true way to evaluate equipment. It's hard to imagine getting such a result without that.

 

[bigshot]

Quote:

 
The sound of equipment often has nothing to do with frequency response, my best bet is it is to do with temporal performance - as manifest in such characteristics such as impact and decay.

 
Bass generally has a very long decay. The attack exists several octaves up from the bass note fundamental. I think he's making it up. Bass imbalances are easily measurable as frequency response.