What is wrong with op-amps?

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#2,621
jan.didden said:
There were 50+ people partaking in the test. Each brings his own experience/interest/preference as to what 'sounds good'. Some have a background in ultra-linear amps, others in SETs, yet others in hybrid open loop. They listen to a pair of musical excerpts and vote based on what they prefer. How can anyone 'measure' anything here??

I know how these processes work, and I carefully selected musical excerpts and presented them in such a way that I thought would maximize impact. And it seemed to work.

I did know that Scotts mike pre was very low noise. Running the Nagra at 15ips meant very short recording time with the 5inch wheels, but also, again, very low noise.
That way I was able to under-modulate a bit so as to avoid any limiting or clipping even with a high dynamic range live concert, preserving dynamic range almost unchanged.
The horn was somewhat dominating I thought, so during the break I very slightly changed mike direction away from the horn, which at the same time allowed the violin to come out a bit more placed. I was also carefull to include a short (15 secs) piano 'solo' to let the audience pinpoint the piano position better, again reinforcing the idea of very good soundstage.
These are the factors that impact how people judge music.

Jan
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Congratulations for the contest result and for the above post which is one of the few in this thread that makes sense.
 
#2,622
jan.didden said:
You really don't get it, do you? Why do you think this is measurable?? That's daft!

Jan
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His entire schtick is to troll.

I don't really care what people's preferences are, but it'd sure be nice to be deliberate about it no? Never mind half the claimed "sonic improvements" on this site (and knowing this is a bastion of sanity) are completely nonsensical.

Of course there will be those that say there are audible effects that are immeasurable, but I like me some measurements for doing engineering.
 
#2,623
DPH said:
Of course there will be those that say there are audible effects that are immeasurable, but I like me some measurements for doing engineering.
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You touched two interesting points.

1. Immeasurable effects. There's a whole bunch of known visual and auditory illusion examples that prove that what you measure cannot predict what you see/hear. The best example is with the dot pattern that seems to move / rotate. You can measure all day long and "prove" that it doesn't move, but as soon as you "predict" based on your measurements that the public will see a stationary pattern, you'll be so wrong.

2. Engineering. Let's not forget that the usefulness of those measuring instruments is limited to "electrical engineering". They won't cover (psycho)acoustics etc.
 
#2,624
Kirchhoff said:
Look, if your goal is "the most technically accurate recording of sound pressure at row G seat 14" then go ahead, but don't expect that that's what the customers at large are looking for.
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Life is to short to waste arguing with you over points which are well defined...
Explain your reply, you asked what the input was, I was pointing out that if you think it is an accurate representation of the concert then you have to factor in all the variables... If you are at any live music performance where you sit has an effect on what you hear... Either you are arguing points for your own pleasure or you did not understand what I had wrote...
 
#2,625
Kirchhoff said:
You touched two interesting points.

1. Immeasurable effects. There's a whole bunch of known visual and auditory illusion examples that prove that what you measure cannot predict what you see/hear. The best example is with the dot pattern that seems to move / rotate. You can measure all day long and "prove" that it doesn't move, but as soon as you "predict" based on your measurements that the public will see a stationary pattern, you'll be so wrong.

2. Engineering. Let's not forget that the usefulness of those measuring instruments is limited to "electrical engineering". They won't cover (psycho)acoustics etc.
Click to expand...

You are now mixing perception with reproduction (music), well known factors, well discussed and two different fields. There is plenty of info on perception and how it is easily fooled, you have pointed out one example with the dots, another is the McGurk effect. These cannot be measured but can be understood if you look at how our perceptions work and how we interact with our world, plenty of documentaries covering the subject.
 
#2,626
marce said:
Life is to short to waste arguing with you over points which are well defined...
Explain your reply, you asked what the input was, I was pointing out that if you think it is an accurate representation of the concert then you have to factor in all the variables... If you are at any live music performance where you sit has an effect on what you hear... Either you are arguing points for your own pleasure or you did not understand what I had wrote...
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Sorry Marce, you were just collateral victim in my discussion with Jan about whether it makes sense to discuss "Hi Fi", "input" and "output" without first defining what they exactly mean (at least for the purpose of the discussion). 😉
 
#2,627
marce said:
You are now mixing perception with reproduction (music), well known factors, well discussed and two different fields. There is plenty of info on perception and how it is easily fooled, you have pointed out one example with the dots, another is the McGurk effect. These cannot be measured but can be understood if you look at how our perceptions work and how we interact with our world, plenty of documentaries covering the subject.
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So how many understanding electrical engineers are taking perceptions into account while they concentrate on BW and THD(+N)? 🙄
 
#2,628
Congratulations Jan on winning the recording shootout. It is not easy to do this with so much competition, and I suspect that your recording skills are exceptional. However, where are the IC op amps in the recording/reproducing chain? Are they in the Nagra 4s (I presume), the microphone preamp developed by Scott? I just can't find any, but I don't have complete schematics for the Nagra 4s at the moment. This is important, from what I can gather so far, because you are essentially using what we might have used in the late 1970's for recording a concert. This was a pre-digital, and often an all discrete time for Nagra. You can make great recordings with this, but why did you not do it with digital equipment? You know, better S/N, much lower distortion, (analog tape measures awful), and essentially what everybody is telling us is SOTA today. For the record, if you measured the distortion, especially SMPTE IM through the tape, most here would be horrified by the measured results, but we know better, subjectively, don't we? '-)
 
#2,629
john curl said:
Congratulations Jan on winning the recording shootout. It is not easy to do this with so much competition, and I suspect that your recording skills are exceptional. However, where are the IC op amps in the recording/reproducing chain? Are they in the Nagra 4s (I presume), the microphone preamp developed by Scott? I just can't find any, but I don't have complete schematics for the Nagra 4s at the moment. This is important, from what I can gather so far, because you are essentially using what we might have used in the late 1970's for recording a concert. This was a pre-digital, and often an all discrete time for Nagra. You can make great recordings with this, but why did you not do it with digital equipment? You know, better S/N, much lower distortion, (analog tape measures awful), and essentially what everybody is telling us is SOTA today. For the record, if you measured the distortion, especially SMPTE IM through the tape, most here would be horrified by the measured results, but we know better, subjectively, don't we? '-)
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+1
 
#2,631

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#2,634
john curl said:
Congratulations Jan on winning the recording shootout. It is not easy to do this with so much competition, and I suspect that your recording skills are exceptional. However, where are the IC op amps in the recording/reproducing chain?
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John, thanks. But. Did you read my description of how it went? Do you really think opamps or not have ANYTHING to do with this? BTW there was an opamp in the mikes, one of Scott's.
My recording skills are non-existing, this was the very first time I did a recording. But instead of worrying about (in this context) irrelevant issues, I concentrated on how people judge MUSIC.

I asked advice from Mike Williams who is the go-to guy for recording and miking techniques at the AES. Said he: 1 - you have no clue about recording, 2 - no time to check out position, 3 - no idea what the room sounds.
Sooo - no-risk, ORTF, 17cm, 110 degrees, at 6 feet. Great advice!

Jan
 
#2,636
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#2,639
Kirchhoff said:
You touched two interesting points.

1. Immeasurable effects. There's a whole bunch of known visual and auditory illusion examples that prove that what you measure cannot predict what you see/hear. The best example is with the dot pattern that seems to move / rotate. You can measure all day long and "prove" that it doesn't move, but as soon as you "predict" based on your measurements that the public will see a stationary pattern, you'll be so wrong.

2. Engineering. Let's not forget that the usefulness of those measuring instruments is limited to "electrical engineering". They won't cover (psycho)acoustics etc.
Click to expand...

Does this make is simpler: "Hey! I like this sound when I do ____ and I don't get that when I do ____. Let me measure the differences in their transfer function and see what's causing that difference". That's being deliberate and "engineering" the sound. Rather than, say, goofing around. Not that playing around with that in DSP isn't a whole load easier and infinitely more flexible, but I digress.

1.) How does that present itself in terms of audio, especially within audio electronics? If one form of electronics has an effect and the other doesn't then we've changed something, even if the brain does some sort of weird interpolation. Or are we talking pan and tone controls? Surely those can be measured.

2.) My point about not covering psychoacoustics is that they must be large enough to be measurable, no? It's not like they're making those "Magic Eye" patterns by accident. Effect size and all.
 
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