Scott I just read a couple of articles by your collegue Harry Holt on the ins and outs of single/dual/quad opamps and packages and when to use which. Interesting!
jan didden
Interesting that you would use the word "quibble" in this regard Mr. Curl. I am remined that on another blog site some time back you reported that you tested various audio cables and your tests indicated that the difference between the least expensive Radio Shack cable and the best cables you tested was that the spurious noise of the 7th harmonic of 5 khz was -120 db for the RS cable, -135 db for the premium price cable. This left no room for even the slightest lingering doubts in my mind, Radio Shack became my preferred cable supplier. However, in recent years and after further consideration I've changed my source of choice. I've switched to Tri-Sonic available at The Dollar Store. 🙂
Well, then one should just add some 'background noise' to a digital system and get everything that anyone would ever want. Perhaps, making it variable in level so that 'old timers' like me could be weaned away from its advantages, and finally happy with digital in its modern glory.
The point that I originally tried to make in reference to the TIM test was the difference between relative spectral levels of the 15KHz and 15.7KHz present in the test signal, and that an obvious rolloff meant that it was TIM(30) rather that TIM(100).
As far as you choosing RS as your reference, why not? And I agree, why pay more for hi fi than what you hear a difference with? I have heard differences in cables, and RS cables have always sounded a little 'off' to me. After the firestorm, being without any hi fi, and slowly rebuilding it, I tried different components, many cost effective, to see if I could happily live with them. RS cables was a beginning. So was a cheap Grado phono cartridge. Why not? Maybe I had become an audio 'snob' and the cheap and easily available stuff was just as good, in most ways, as the expensive cables and phono cartridges that I had acquired, over the years. Unfortunately, it didn't work out, and I put the cables and Grado aside to use 'better' audio components, but I tried, for about 1 year, to use more 'cost effective' components.
As far as you choosing RS as your reference, why not? And I agree, why pay more for hi fi than what you hear a difference with? I have heard differences in cables, and RS cables have always sounded a little 'off' to me. After the firestorm, being without any hi fi, and slowly rebuilding it, I tried different components, many cost effective, to see if I could happily live with them. RS cables was a beginning. So was a cheap Grado phono cartridge. Why not? Maybe I had become an audio 'snob' and the cheap and easily available stuff was just as good, in most ways, as the expensive cables and phono cartridges that I had acquired, over the years. Unfortunately, it didn't work out, and I put the cables and Grado aside to use 'better' audio components, but I tried, for about 1 year, to use more 'cost effective' components.
No, the spectrum of the masking noise is also important. When the introduced noise is at the same level as the digital artifacts, the resulting noise sounds different. I suspect your masking noise would need to be at least 10 to 30db louder, then the digital system would be noisy.
Shure made some wireless microphone systems that had signal to noise ratios equal to or better than their competitors, but the audio for video guys would not use them. The practice was to turn up the gain until you heard noise. The Shure noise sounded "Digital" and so the final product was branded as "noisy," specifications did not matter. The other brand's noise matched that of the mixing console and was considered normal.
Does anyone care about my anecdotal tales?
Well, I have classic measured noise curves from analog tape recorders, including one tube unit. It sort of looks like an inverted A weighted eq, (like DUH!) Maybe we should add THAT noise characteristic to the digital circuits and then they will be 'perfect'.
A big frustration I have is the audiophile demand for vinyl. Often they are cut from a high quality digital master, many times at higher bit rate and sample rate than CD and sometimes the original is available for download. The most absurd variation is taking one of the disks made this way and transferring back to digital and offering it on line.
Some mastering facilities use several "sweetening" tricks including either a tape simulator or actually passing a digital recording through a tape recorder to "improve" the sound.
Is high end audio an accurate mirror of an original performance or just the best makeup/retouching job? I have heard a number of very premium, beautiful sounding systems that have little connection to reality. The best description I have heard of this phenomena is "the best violin recording turns out to be a viola". Reality isn't always pretty, strings aren't always sweet, the voices are harsh and strained at times, but the emotions are real and too much pretty leaves me missing the point.
I note and understand, Demian, that you have as much long term experience as I have, and perhaps even more in present recording technology. I must agree that present record technology leaves a lot to be desired, as it is often mixed with digital technology. I hate that. I had this problem a week ago at Audio Arts, in Campbell, CA when listening first to CD, then a digital remastered vinyl, finally to a used, all analog vinyl record of 'Rumors' by Fleetwood Mac. In many ways, the digital sounded better, but with artifacts that I wanted to avoid. I can understand why people might want to stay with the convenience of digital. Still, the 'magic' is in the older original recordings that are all analog, played back on first class phono equipment. That is really my argument, just like the Porsche needs twisty roads to make it really show its stuff. Driving it to the store and back, does little to show it off. It's the same with audio reproduction. Twenty years ago, before the firestorm, I had a whole shelf of first class records and playback equipment, even better, in general, than I have today.
Also, I had another shelf of master tapes recorded on my own master recorder at 15 ips and 1/2 track. All lost. I don't even try to impress people these days with my playback, even though I like it well enough, and I know what can be done in audio reproduction of the highest quality, and used vinyl is now easier for me, than rebuilding my master tapes.
Also, I had another shelf of master tapes recorded on my own master recorder at 15 ips and 1/2 track. All lost. I don't even try to impress people these days with my playback, even though I like it well enough, and I know what can be done in audio reproduction of the highest quality, and used vinyl is now easier for me, than rebuilding my master tapes.
The problem begins with the recording session. Modern recording engineers don't have a musical education like the old guild...
Next point, it is not possible to make an exact image from an musical event, only an approximation of the orchestra / group, the room etc. The microphones are the next bottleneck... and so on.
Then at least a digital conversion of an analogue signal, here the A/D conversion of music, means to have quantization noise - which is a synthetic noise and interefes even when it's level is minus 120dB.
Next point, it is not possible to make an exact image from an musical event, only an approximation of the orchestra / group, the room etc. The microphones are the next bottleneck... and so on.
Then at least a digital conversion of an analogue signal, here the A/D conversion of music, means to have quantization noise - which is a synthetic noise and interefes even when it's level is minus 120dB.
John, you do know, of course, that the master tape for Rumours was in terrible shape by the time the records were mastered? The engineer involved (whom I used to work with) says that you could just about see through it, the flaking and wear were so bad.
I find it hard to understand why the spectrum of the low level "dither" noise that masks digitizing at the extreme low end of the dynamic range of a recording/playback system capable of nearly 100 db of dynamic range matters most of the time given that most recorded music is pop music with dynamic range inherently limited to about 10 db and gain often pushed deliberately to the clipping point and beyond at the upper end of that 100 db range to make recordings sound louder when played commercially.
I tested RS cables to determine if they had any audible effect on sound. IMO many audiophiles fall into the trap of comparing one cable to another to see which they like better. As a cable has a specific function, namely to connect two points in a circuit without causing audible degradation of the signal, that is the only criteria I judge them by other than reliability, quality of build, and cost. Therefore the ideal test is not between cable A and cable B but between cable A and an ideal cable, a shunt. This test is very close to the theoretical ideal when performed by comparing the cable in a circuit and out of it. I use the tape monitor loop between the recording output and monitor input and shunting the cable using the monitor tape/source switch. The test is of course only valid if there is no buffer stage in the monitor output. I have yet to hear any difference in inexpensive cables. (One so called audiophile cable with a well known brand given to me as a gift was an unqualified disaster in this test.)
Not satisfied with this test, I put the RS cable to a much tougher test, I used it as a video cable between the output of a VCR and the video monitor of a 36" Sony XBR analog TV set. The shunt was the direct RF feed of the same cable signal to the TV tuner. I could see no difference in any respect on any channel. This included contrast, boundary sharpness, and color tint and saturation. This means the cable was flat to at least 7 MHZ, over 300 times the bandwidth of an audio signal. And a DC ohmmeter demonstrated the cable is flat to 0 hz.
This hardly came as a surprise to me because the telegrapher's equation is one of the best models for electrical circuits we have and correlates extremely well to measured performance. The wire and cable industry has provided outstanding low cost solutions to many of even the most difficult problems. If you don't like RS, try Belden, their products are excellent and many after market products are probably Belden rebranded and marked up many times.
Revolutions are usually outdated, been done since the start of cableholism, e.g. vdH's resleeved Berkenhoff & Drebes versions.
(Keep 'm coming, Mr Simon)
A question for the gallery. Can anyone produce some distortion graphs of a modern SOTA line contact stylus as the azimuth is micro-adjusted? I'm interested in the actual degree to which the distortion is reduced. I suspect the performance is still lamentable at 5kHz.
My own experiments are dated, I took a fresh copy of the RCA STR series test records and compared the $15 Grado to a Monster Alpha 1 and got no detectable difference @3kHz. But I won't claim I was being rigorus.
My own experiments are dated, I took a fresh copy of the RCA STR series test records and compared the $15 Grado to a Monster Alpha 1 and got no detectable difference @3kHz. But I won't claim I was being rigorus.
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Regarding the phono v digital issue, I ran across an interesting site of Richard Brice a while back, who also published in WW, where he states that the problem with digital may be due to too much channel separation!
As quoted from his web site:
"Several years ago I was involved in my first recording which appeared on vinyl and CD. It gave me a unique opportunity to compare analogue and digital reproduction because I also had a copy of the original master tape. Unhesitatingly, I should say, the CD was 'nearer' the master, but vinyl produced a 'better' stereo image - in fact, better than the master tape! A conundrum indeed.
After much deliberation and armchair theorizing I set about doing some experiments. Late nights with an oscilloscope eventually uncovered that electrical and mechanical crosstalk within the cartridge and pre-amp were causing a stereo image manipulation which was similar to that brought about by the Blumlein 'Shuffler' circuit and Edeko's loudspeakers - all the important narrowing of the stereo image at high frequencies. It supported what I and so many hi-fi fans knew to be the case, that vinyl really does sound better than CD - especially in LP's presentation of a realistic soundstage."
A commercial product called "Francinstien" supposedly corrects the problem. On his web site, he has two mp3s, one processed and one unprocessed for comparision.
His web site is:
Perfect Pitch Music . Richard Brice . composer . inventor of FRANCINSTIEN
The link to his Francinstien info is here:
Francinstien
Several years ago we communicated by email, and he sent me the attached schematic of a simple circuit to use to get the basic function of his product. Since then, he has revised the Francinstein (2010), as discussed on his web site.
As quoted from his web site:
"Several years ago I was involved in my first recording which appeared on vinyl and CD. It gave me a unique opportunity to compare analogue and digital reproduction because I also had a copy of the original master tape. Unhesitatingly, I should say, the CD was 'nearer' the master, but vinyl produced a 'better' stereo image - in fact, better than the master tape! A conundrum indeed.
After much deliberation and armchair theorizing I set about doing some experiments. Late nights with an oscilloscope eventually uncovered that electrical and mechanical crosstalk within the cartridge and pre-amp were causing a stereo image manipulation which was similar to that brought about by the Blumlein 'Shuffler' circuit and Edeko's loudspeakers - all the important narrowing of the stereo image at high frequencies. It supported what I and so many hi-fi fans knew to be the case, that vinyl really does sound better than CD - especially in LP's presentation of a realistic soundstage."
A commercial product called "Francinstien" supposedly corrects the problem. On his web site, he has two mp3s, one processed and one unprocessed for comparision.
His web site is:
Perfect Pitch Music . Richard Brice . composer . inventor of FRANCINSTIEN
The link to his Francinstien info is here:
Francinstien
Several years ago we communicated by email, and he sent me the attached schematic of a simple circuit to use to get the basic function of his product. Since then, he has revised the Francinstein (2010), as discussed on his web site.
Attachments
SY, it doesn't work quite like this. What happens is that the 'final' master tape is made, that is mixed from 16 or more channels down to 2 channels.
How do I know? I was there when 'Tusk' was mixed down to 2 channels.
What happens from there, is that more copies are made, by whatever way is best. The best way, when 'Tusk' was made was to just replay the multichannel tapes and use an automatic mixing process, the mix levels derived from the approved final mix done manually. In practice, a number of PROTECTION and 'SERVICE' masters are made and some are sent to the disc recording engineer to make the vinyl mix. Perhaps another to make the analog cassettes, etc. Unfortunately, each of these tapes wear out in time, AND IF the mixing engineers do not think that a album will sell more than a predicted amount, they only make a certain limited number of masters. Guess what? 'Rumors' was so successful, they wore out the 'service' tapes. Perhaps it was live mixed, so it was difficult to impossible to make fresh masters to the quality of the originals. The originals were OK. How do I know? I heard the original mixdown of 'Tusk' and it was GREAT. My problem with the band, is that they had run out of protection masters with their previous effort 'Rumors', and THEY WERE ASSURED that perfect sound forever would never drop any information or wear out.
SO, they went to a digital mix, which had the usual degraded sound. Ironically, as I predicted at the time, they lost sales, and their effort to protect their sound, actually ruined it, and the rest is history.
How do I know? I was there when 'Tusk' was mixed down to 2 channels.
What happens from there, is that more copies are made, by whatever way is best. The best way, when 'Tusk' was made was to just replay the multichannel tapes and use an automatic mixing process, the mix levels derived from the approved final mix done manually. In practice, a number of PROTECTION and 'SERVICE' masters are made and some are sent to the disc recording engineer to make the vinyl mix. Perhaps another to make the analog cassettes, etc. Unfortunately, each of these tapes wear out in time, AND IF the mixing engineers do not think that a album will sell more than a predicted amount, they only make a certain limited number of masters. Guess what? 'Rumors' was so successful, they wore out the 'service' tapes. Perhaps it was live mixed, so it was difficult to impossible to make fresh masters to the quality of the originals. The originals were OK. How do I know? I heard the original mixdown of 'Tusk' and it was GREAT. My problem with the band, is that they had run out of protection masters with their previous effort 'Rumors', and THEY WERE ASSURED that perfect sound forever would never drop any information or wear out.
SO, they went to a digital mix, which had the usual degraded sound. Ironically, as I predicted at the time, they lost sales, and their effort to protect their sound, actually ruined it, and the rest is history.
I discussed this with Keith Johnson recently. Two issues, the first being that the analog tapes will have deteriorated over the years and will have lost high frequency details that the vinyl will have preserved. Second, playing vinyl in the acoustic space you are listening in will add "air and space" to the recording. It would not take much of a thought experiment to see how this is possible. The interesting experiment would be to set a stylus on a motionless disk and play music in the room recording the output of the cartridge. I could see an audiophile market for digital recordings with this effect added. Perhaps this is why many audiophiles erect a shrine to equipment as close as possible to their speakers.
I have not been able to get interest in an acoustic isolation chamber for turntables and this effect is probably why.
I have not been able to get interest in an acoustic isolation chamber for turntables and this effect is probably why.
The originator of the commercial software has a WEB site with contact details. Maybe he answers if you ask him directly (feickert.com).
As an aside, Jan Allaerts presents distortion figures for his different cartridge models which are ranging from 1.5% down to 0.01% depending on how far you go up in the hierarchy. His test setup was:
"Goldmund Turntable / Air Tangent arm with exterior wiring
NEUTRIK AUDIO TEST A 1 and TP 402"
If the lower figures are really correct - note tangential arm hence no lateral tracking error - then I think there is nothing to lament, except off course the price tag. And there is only one way to find out.
Any record with as low as 0.01% harmonic distortion in a vinyl groove is physically impossible. Order of 0.1% - 1% would be true, depending on rpm (45 is better than 33), amplitude, frequency and diameter - distortion is getting higher near the center of the disk. Theoretical values of distortion are known and cannot be outperformed.
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