solderdude
Grand Contributor
Almost correct... the more correct answer is in post #431It's because tubes physically roll.
Your answer had me rolling across the floor.... while shouting; 'I'm not crazy ...I am a vacuum tube'
Almost correct... the more correct answer is in post #431It's because tubes physically roll.
I am ashamed. I knew this.Almost correct... the more correct answer is in post #431
Your answer had me rolling across the floor.... while shouting; 'I'm not crazy ...I am a vacuum tube'
Bit of an exercise in futility doing it all again then
Still - why let that stop you.
Point is "purely subjective" findings can only be of interest to the subjective listener. They cannot inform anyone else about what they might perceive in the sound from a piece of gear. (by the very definition of the word subjective). No-one knows if your "impressions" come from the sound, or from your unconscious brain.
It therefore makes it pretty pointless reporting on them. Here, at least.
This is typically what happens with threads where Amir or someone else shows data that "x" doesn't change the audible sound: some people take it as a personal challenge to either widen the goal posts or move the game to a completely different sport just to prove a point (or stroke their ego).Nah ... we get your point that not all op-amps are the same and in certain applications they matter.
The thing is in the discussed amp ... with the suggested op-amps would 'rolling' make sense.
I always thought the term was derived from "Roll your own" as in cigarettes or joints.Almost correct... the more correct answer is in post #431
Your answer had me rolling across the floor.... while shouting; 'I'm not crazy ...I am a vacuum tube'
Once again, I am saying nothing about audibility. However, if it is legal to have a SINAD chart competition in this forum, with the audience waiting for new winners, is it illegal to show that opamps, depending on the application, do make a difference as well and may contribute to those SINAD charts wars?? What is the difference? The same approach.And distortion below 0.0003% is that really audible ?
No disrespect intended, but if this is 'My personal, subjective conclusion' from 'purely subjective and impressionistic findings', why should that be of any interest to any if us?I've been distained a good many times for reporting my purely subjective and impressionistic findings, so I'm used to the abuse. I've rolled op amps a few times and have found subtle differences.
Most striking was my recent experience with my VTV Purifi 1ET400A stereo amp. Originally I ordered this from VTV with the Hypex Eval I/O buffer. Immediately and spontaneously I was disappointed with at least one aspect of the sound versus my previous Hypex NC252MP amp; the top end, especially and higher volumes, was "screamy" and unnatural. Almost right away I ordered VTV's own I/O buffers with Sparkos SS3602 (discrete) dual op amps. The VTV buffers that accommodate 8 pin DIPs and larger form factor "pro" op amps.
With the VTV buffer with the SS3602's the sound was improved in that top end respect: "screaminess" gone. However I proceeded to try several other op amps I had lying around from previous experimentation, including OP2134, the venerable OPA247, the Burson V6 Vivid discrete, plus I ordered the OPA1612.
My personal, subjective conclusion after much swapping back & forth was that I preferred the Sparkos SS3602's for having the nicest transparency and natural top end. Runner up was probably the OPA1612. It's worth mentioning that the VTV buffer was designed by the same designer as the Sparkos op amps, (which I didn't know at the time), so the fact might have optimized the buffer and op amp combination.
But I note & emphasize that difference among these op amps were extremely subtle excepting for the Hypex buffer that was distinctly awful in context of my VTV Purifi amp. (I knew but now don't recall the surface mount op amp used in the Hypex.)
In case you stick with audibility, almost nothing matters, talking about contemporary DACs and amplifiers, except for power and complex load drive ability.This is typically what happens with threads where Amir or someone else shows data that "x" doesn't change the audible sound:
Yes, that's where we are at now a days with performance of most components.In case you stick with audibility, almost nothing matters, talking about contemporary DACs and amplifiers, except for power and complex load drive ability.
You're right. For these and other reasons (commercial, for example) the overall configuration is stable.The problem here is that they have already 'proven' that the differences exist and have confirmation from the manufacturer and countless people.
Then we ask them to doubt that what they 'know to be true' and have to prove that they are right to a bunch of tech guys that only measure gear.
The procedure indeed is not that difficult, doing it properly is though and involves other people to assist which cannot give any 'hints'.
Doing this 'long term' (as that always seems to be the counter argument) takes months to complete.
Besides ... what IF these tech guys were right and it turns out statistically they cannot clearly identify that what they always could.
Are these people 'open' enough to accept that testing methods is what is paramount to perceive differences.
Never going to happen (well maybe a handful) so the 'opposing views' will continue and nothing would change.
You 're probably not very involved so you're excused but @solderdude is not.This is typically what happens with threads where Amir or someone else shows data that "x" doesn't change the audible sound: some people take it as a personal challenge to either widen the goal posts or move the game to a completely different sport just to prove a point (or stroke their ego).
In a recent "Power Cords don't change the sound" thread, there was a poster who spent pages arguing that they do if there is a grounding issue that is audible as ground hum in the signal.
I guess it needs to be explicitly spelled out in bold words in the top of the OP that the discussion is dealing with OP amps (or power cords, or RCA cables, etc) that do not degrade the baseline sound/performance (whether intentionally or because of poor designs). Even though nearly all of us know this is implied...
The difference is that in this particular amplifier the differences between op-amps don't really matter as the class-D stage is what determines the final result.Once again, I am saying nothing about audibility. However, if it is legal to have a SINAD chart competition in this forum, with the audience waiting for new winners, is it illegal to show that opamps, depending on the application, do make a difference as well and may contribute to those SINAD charts wars?? What is the difference? The same approach.
Now that you said "sockets", we know that some OPAs need their caps as close as possible right,like just on their leg.I did some mistakes too. At the end, the socket was worn and I had false (negative) results, as in super high levels of distortion. So the real interesting discovery (for me) was not to do that too much. Not doing at all, because it's useless, was the real conclusion
Thanks for making me read this platinum note.... then we know good is good enough. ...
They are not. Remember the discussion regarding noise in vinyl context, great contributions that are for sure going somewhere. But on opamp rolling the board routinely chases its tail. The 'subjectivist's' perspective cannot be challenged by engineering. It is designed this way. It may appear plain impractical to more sophisticated folks, but so it is.Debates are pointless, so are the discussion forums. Disappointment.