john curl said:
I was talking about posting plots from your 1977 AES paper with Matti Otala, I thought you had something new to talk about. Talking about the "sound of op-amps" and using the uA741/709, LM301 as examples HAS become tired.
And who is that Milan guy cloneing the Blowtorch taking cheap shots at me? He needs to get a life and realize that being a DIY parasite has its risks.
SY said:
He posted a cheap shot on his web site directly at me.
1) I posted a schematic or link to a schematic of the Neumann mic in question at the beginning of my discussion.
2) I pointed out that the charge amplifier was invented and patented in 1950.
3) I showed how you could DIY a mic that was capsule noise limited and had 8V p-p output on a 9V battery for $2 or so in parts (less capsule).
4) I did not make a plugged nickle on any of this.
Reality sometimes bites you in the 'you know what'. The measurement is reality, as I made exactly the same measurement with exactly the same conditions, and many, many more variations, with the SAME equipment, when I worked on the paper in 1976. It is NOT a fluke or a mistake. Only an expert in FM modulation, Mitch Cotter, could give us the key to source of the unknown distortion artifacts that were not previously accounted for.
What gets me is that we could have figured this out 33 years ago, IF we had inside knowledge of FM modulation at the time. This is not the only example, in fact Mitch Cotter pointed out that he saw this artifact in an earlier paper by Matti, without me being involved. The test equipment was done with the HP3581 wave analyzer, exactly like the one now in the possession of SY. Anybody need one? I have 2 extra for sale in the SF bay area.
What gets me is that we could have figured this out 33 years ago, IF we had inside knowledge of FM modulation at the time. This is not the only example, in fact Mitch Cotter pointed out that he saw this artifact in an earlier paper by Matti, without me being involved. The test equipment was done with the HP3581 wave analyzer, exactly like the one now in the possession of SY. Anybody need one? I have 2 extra for sale in the SF bay area.
Oh yes, 'PERFECT SOUND, FOREVER'.
Why don't you discuss it with Barrie Gilbert?
Also, I suspect that all 'spurs' are NOT equal, when it comes to the human ear. How about alaising artifacts, are they not easier to spot than simple harmonic distortion? Yet they would only appear as 'spurs' except 'out of place' from any harmonic relationship.
Why don't you discuss it with Barrie Gilbert?Also, I suspect that all 'spurs' are NOT equal, when it comes to the human ear. How about alaising artifacts, are they not easier to spot than simple harmonic distortion? Yet they would only appear as 'spurs' except 'out of place' from any harmonic relationship.
I would like to mention a paper by Cabot, Audio Precision -
Cabot, R.C.: Comparison of Nonlinear Distortion Measurement Methods
It includes sine-square test as well, with original paper cited. Cabot mentions there were 25 components generated within audio band that were greater than 0.1% of the 15kHz amplitude, i.e. more than 9 described previously.
Cabot, R.C.: Comparison of Nonlinear Distortion Measurement Methods
It includes sine-square test as well, with original paper cited. Cabot mentions there were 25 components generated within audio band that were greater than 0.1% of the 15kHz amplitude, i.e. more than 9 described previously.
As we progress from the first 'flying spur' sighting, we can now move forward in time.
BUT, I must warn you, that you are foolish IF you think that Scott's and his friend's designs are in most audio equipment. More like the 741, in most cases.
I offer proof: Raytheon 'Linear FET Array Design and Applications Manual' 1991, which moves things up 25 years from the 741 type circuit. Same thing! SL Rate .5V/us typical
And if you were an engineer working at Dolby, what would you choose?
BUT, I must warn you, that you are foolish IF you think that Scott's and his friend's designs are in most audio equipment. More like the 741, in most cases.
I offer proof: Raytheon 'Linear FET Array Design and Applications Manual' 1991, which moves things up 25 years from the 741 type circuit. Same thing! SL Rate .5V/us typical
And if you were an engineer working at Dolby, what would you choose?
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