Can't say I disagree with that Joachim. Except for the sauage; I don't know this particular saying.
But these mechanical things like the turntable platter and similar things with speakers are enormous compared to a modern opamp. There's no comparison; you can't say, aha, I clearly measured and heard a difference in my turntable, therefor it could be that opamps cause changes in sound stage. Bad analogy.
BTW I was in Luxembourg this weekend, in a shop called L'Audiophile (really!) listened to Audio Physic Scorpio speakers. Your design?
jan didden
Words out of my mouth. Whether it's distortion, frequency response, or crosstalk, the audible thresholds are rather high. It takes gross amounts of inverse crosstalk, for example, to audibly spread an image- that's why the earlier link was to an effects box that has to be deliberately built in order to actually change the sound. So handwaving about the potential contributions of distortion, frequency response, and crosstalk of relatively linear boxes of gain is inapt- the experimental evidence doesn't support the hypothesis.
If there's a difference due to some factor, it will be large, easily measureable, and it would then be well-known to engineers in general.
If there's a difference due to some factor, it will be large, easily measureable, and it would then be well-known to engineers in general.
True enough. For some reason I was thinking about power amps, not op amps. Sorry.
Under ideal conditions, sure. Not having tested them a various freqs and under different conditions, I can't say. Except those in the output of the DCX2496, which can be rather nasty.
That is a conundrum.
I accept that chasing ephemera in the form of unverified (by test) observations could be a waste of time. However, it is a fact that some early "subjective" reviewers thought that early CD sounded terrible, but at the time the technical analysis available or at least tendered as a response demonstrated that CD reproduction was perfect. It certainly possessed low THD and flat frequency response.
It is now not seriously doubted that there were real problems with early CD players not least in the areas of jitter and I/V conversion. That said, there is still the problem that once measurable anomalies are uncovered, the demonstrable audibility of them becomes the issue.
Frustrating; and ultimately the reason why these type of threads on this forum become circular and ultimately a source of more heat than light.
but we have studies of jitter audibility which find 10-100s of nS being necessary for sucessful blind ABX
and I/V conversion in flagship audio DAC datasheet reference designs often still use 5532/4 op amps
so I'm uncertain that it is at all agreed that those are/were "established" explainations
and I/V conversion in flagship audio DAC datasheet reference designs often still use 5532/4 op amps
so I'm uncertain that it is at all agreed that those are/were "established" explainations
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Jan, i did not design that speaker. I left Audio physic in december 2004 but somehow the new designer did not change my original philosophy much. The last speaker i designed 100%
myself at Audio Physic was the Virgo that got a 17 page review in Stereophile i think in 1996. I worked then more in management duty and as spriritus rector.
Concerning 44k/16Bit we have an interesting discussion on the High Resolution Forum triggered by no less then Bob Katz himself that for reproduction it is sufficient to pass as transparent BUT NOT FOR RECORDING. It is called " The Third Hypothesis ".
myself at Audio Physic was the Virgo that got a 17 page review in Stereophile i think in 1996. I worked then more in management duty and as spriritus rector.
Concerning 44k/16Bit we have an interesting discussion on the High Resolution Forum triggered by no less then Bob Katz himself that for reproduction it is sufficient to pass as transparent BUT NOT FOR RECORDING. It is called " The Third Hypothesis ".
I have seen criticisms of the Jitter testing failing to distinguish between correlated and uncorrelated jitter; once again bringing into question whether what was tested was sufficiently relevant to make it meaningful.
Yes, I agree there are flagship machines using data sheet I/V conversions with 5534 as the convertor despite its slew rate limitations and the ultrasonic unloading of the virtual ground creating distortion mayhem beyond the audio band. The question is not whether flagship CD players use this but whether they can be sonically improved using a different I/V scheme.
I was there at the birth of CD and got to hear the early players, I have no double blind tests to back up my observation that they sounded beyond bad.
Robert, if you can't hear it without peeking, you can't hear it.
To date, I'm unaware of ANY test that shows audible differences in depth, imaging, soundstage, whatever due to electronics (excluding some really rare pathological case or deliberate effects boxes), as detected by ear alone. If I'm ignorant of some good test demonstrating this, I'm sure someone will be happy to correct me. Otherwise, we're talking the same level of evidence as UFO abductions.
To date, I'm unaware of ANY test that shows audible differences in depth, imaging, soundstage, whatever due to electronics (excluding some really rare pathological case or deliberate effects boxes), as detected by ear alone. If I'm ignorant of some good test demonstrating this, I'm sure someone will be happy to correct me. Otherwise, we're talking the same level of evidence as UFO abductions.
Which was my point at least to an extent. I evaluate changes I make to my system (when I can) without peeking by listening to those changes to my system blind with the aid of friends, however I can't present you with data which means there is no point me telling you.
I own up to not evaluating the changes, if any to soundstage after separating the front end power supplies to my power amps simply because I couldn't do a stereo before and after evaluation in a reasonable time frame. The best I can do is report what I observed having made the change. No proof, I admit it.
I am not disagreeing with you. I am just coming from the opposite direction. Bad layout, supply rail conducted artifacts etc. The list can be as long as you care to make it.
Does it measure worst but sounds better ?
+10... I'm of the same camp , pleasant music, nuetral amp ...
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