Or LIGO. I don't know if I'll get over this, the head of instrumentation engineering at LIGO just called our CTO and asked to talk to the designer of the AD797. Apparently it was a key component (in his words).Just think, I helped.
Well at least ask for a T-shirt! I'd be well chuffed !
The interesting thing will be a quench of ITER. The plasma is to support 1 or 1.5 million amps, the central solenoid stores a gigajoule, the pf coils another gigajoule, and the structure has to support fault forces of 180 mega-newtons vertically.
A gigajoule here, a gigajoule there...pretty soon it'll start to add up.
I'm reminded of the clancy movie bomb technician t-shirt.." I'm Russian bomb technician, if you see me running, you should keep up.""
John
Or LIGO. I don't know if I'll get over this, the head of instrumentation engineering at LIGO just called our CTO and asked to talk to the designer of the AD797. Apparently it was a key component (in his words).
Or, they just found out where their false positive signal came from, and they want heads..Sometimes, the 15 minutes of fame happens just before the trap door is released...
Congrats..
John
Yes. And, if SY did his thorough home work, he would learn more about the audible affects of jitter (as well as the correlated measurements). Just a simple review of the AES et al will point to the established jitter limits needed to be inaudible.
Regarding more SY jumping to conclusions..... I had already bought their ADC and DAC (2nd gen) Before I called him and talked. The 2nd gen does sound more accurate than their 1st gen DAC.
THx-RNMarsh
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So, don't leave us hanging, how much jitter was there in the respective Benchmark DACs and how many orders of magnitude is it beneath the lowest observed level of audibility? You know, with exceptional claims, data and such.
Musical Fidelity V90-DAC D/A processor Measurements | Stereophile.com
$300 DAC, note the jitter measurement. All below the green line of theory.
Oh and http://www.nanophon.com/audio/jitter92.pdf has the graph of jitter inaudibility in it.
So I would say that jitter was well solved even in cheap products. The Benchmark is wonderfully engineered, but around 7x what you need to pay to get superlative performance.
$300 DAC, note the jitter measurement. All below the green line of theory.
Oh and http://www.nanophon.com/audio/jitter92.pdf has the graph of jitter inaudibility in it.
So I would say that jitter was well solved even in cheap products. The Benchmark is wonderfully engineered, but around 7x what you need to pay to get superlative performance.
Dick doesn't want to see that stuff nor does he have any interest in DBT listening tests.
Yes, but at least it's not one of those products where you spend a fortune for something with vastly inferior performance, which is so often the case. The measured performance is excellent.
Now you are getting closer to reality. Just as the shifting of audible noise/distortion artifacts to above 22KHz was supposed to be a final solution, it causes other problems down-stream. Some products have high levels of extraneous idle tones and some have little or none. But we dont measure HF.
Once jitter spectrum analysis was applied and then found that lower jitter sounded better and then to what point was jitter low enough for most people.... not all products are equal. Some better than others. So, you need to know what YOUR equipment actually measures in your system. preferably from end-to-end and wide band.
So why does BenchMarks DAC one and two sound different? Benchmark says its about jitter and analog improvements.
THx-RNMarsh
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I know I shouldn't do this without the backup pictures but with standard parts (AK4115) and spdif I get essentially no jitter. I really think the jitter bug has been vanquished. Its not the bad guy in a halfway decent DAC effort. I did a lot of measurements which yielded no bad guys in recent chip sets. Below is a measurement from some time ago and chips that are two generations old. Newer stuff is better. Its scaled about the same as the Stereophile pictures.
Also I don't see much difference in distortion etc. between 1X and 4X. The AK4490 is a little better at 44.1K multiples than at 48K multiples but that was an intentional internal timing tweak (or so I'm told). Second picture is distortion at 384 KHz. As you can see the 2nd harmonic is at -120 dB. Its hard to see how that could ever be audible.
Also I don't see much difference in distortion etc. between 1X and 4X. The AK4490 is a little better at 44.1K multiples than at 48K multiples but that was an intentional internal timing tweak (or so I'm told). Second picture is distortion at 384 KHz. As you can see the 2nd harmonic is at -120 dB. Its hard to see how that could ever be audible.
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hi DEmian,
I am not sure what you are saying here...... certainly some dac chips via spdif are pretty good in this regard.
Is that what the majority of average consumers always gets in the many product categories containing DAC's from Pioneer, Sony, Panasonic, Marantz etc --- or from one of these:
Top 5 Best USB DACs Under $200 | Heavy.com
THx-RNMarsh
I am not sure what you are saying here...... certainly some dac chips via spdif are pretty good in this regard.
Is that what the majority of average consumers always gets in the many product categories containing DAC's from Pioneer, Sony, Panasonic, Marantz etc --- or from one of these:
Top 5 Best USB DACs Under $200 | Heavy.com
THx-RNMarsh
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Because Benchmark told you it sounded better over the phone and the reviews said the same? DAC1 was also down in the weeds for jitter.
More jumping to your own conclusions or wishful thinking? ----- I bought it based only on superior technical test data and price I wanted to pay. Didnt call engineer until after I had purchased and then heard the DAC two. And, I was trying to find answers as to why HD down loads and masters sound better than CD.
But 2 years before that, I had Demians USB-DAC music player (Auraliti) and played HD down loads thru its usb port. It was great sounding..... that started more hardware buying and tests. Maybe Demian will tell us what he did to make a better DAC mouse trap for the money and what specs/performance upgrades did he do to make it better? As good as it is, he said it could perform/sound even better with a better dac. So, I went out and bought a better dac.
THx-RNMarsh
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I have no problem if you chose based on the best measurements. I did the same for the power amps I am building. But I have looked at the DAC1 measurements and, bar volume balance if you use the inbuilt pot I cannot see anything that is above audible thresholds.
Pride of ownership in having the cleanest dac on the block I get, I just can't see how it can sound better in reality. And yes if I had the disposable I'd probably get a DAC2.
Pride of ownership in having the cleanest dac on the block I get, I just can't see how it can sound better in reality. And yes if I had the disposable I'd probably get a DAC2.
You're assuming without any evidence that they do. Or that either sound different than much cheaper DACs.
RNM
Please don't feed the trolls. Particularly the king of trolls.
In a football stadium I use a master clock to synchronize all the audio digital data. I can get system wide jitter to under 12 nS. In the control room folks notice if the system unlocks from the clock. That puts jitter above 20 nS but I believe still under 50 nS.
Many pro systems use a master clock on the digital mixing console as the clearly misled folks who do that believe they hear a big difference.
Please don't feed the trolls. Particularly the king of trolls.
In a football stadium I use a master clock to synchronize all the audio digital data. I can get system wide jitter to under 12 nS. In the control room folks notice if the system unlocks from the clock. That puts jitter above 20 nS but I believe still under 50 nS.
Many pro systems use a master clock on the digital mixing console as the clearly misled folks who do that believe they hear a big difference.
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