They think it is audible and I know it is audible what ever the reason.
My DAC-2 is for sale.
-RNM
Jan, I'm surprised at you. It is known that a square wave can have virtually any rise-time, and you have to put an added filter (30KHz in this case) to keep the rise-time within the audio signal expectations. Of course, we often use TIM(100) or a 100K roll-off filter for our more serious measurements, but we had to give something practical that met 'reasonable worst case rise-time', and 10us is a pretty reasonable worst case rise-time. Of course the mistracking garbage can extend up to 500KHz (measurable with the Ortofon), but usually only extends to 200KHz with most MC cartridges, see fig. 5.
See, that's the difference. You are allowed to Believe, we the Infidels are supposed to ask. Been there, done that, such people are trying to dupe you as long as they don't realize you know what you are talking about, after that you only get a deafening silence.
The white paper you are quoting https://benchmarkmedia.com/blogs/application_notes/12142221-jitter-and-its-effects is malarkey, btw:
Anybody trying to ask for proof of this statement about our ears, I'm ready to bet you'll get zip, nada.
Sorry John, I don't get your point. You made the comparison to the TIM30 and the scratch from the cart being almost identical. It seems a logical step to interpret that apparently the cart is similarly bandlimited as the TIM30 signal.
Or maybe I should assume that it is the scratch and not the cart that is similarly bandlimited as the TIM30? In either case, it tells me that if the phonopre can handle a TIM30, it can also handle the scratches.
Or am I missing something?
Jan
I might suggest finding the articles by Richard S. Burwen regarding tick and pop reduction/elimination published in Audio I believe in the 80's, (Transient Noise Eliminators) not sure when. I can't find what I remember reading, somewhere, at some point in time 
I recall he had data on click and pop from the cartridge before equalization. Primarily the bandwidth and level data that has been being discussed.
Cheers
Alan
I recall he had data on click and pop from the cartridge before equalization. Primarily the bandwidth and level data that has been being discussed.
Cheers
Alan
I'm trying to understand the plot in the benchmark paper, fig 2. it shows two signal levels vs time and supposedly one w/ jitter and the other without. And its all about interface jitter, which is nonexistent in USB. Also the CS8414 receiver is really old, the datasheet is 18 years old and it doesn't support 24/192. The less than $2 AK4118AEQ | Product | AKM - Asahi Kasei Microdevices can get 20 pS from Toslink in my measurements.
I have said before the jitter problem is solved in so many ways but its a great marketing story. Very few people are equipped to measure it and fewer actually do measure jitter. But its mysterious and technical therefor a great story. My first run in with Audio MFR's lying with John Iverson and his magic phono system. He claimed it had a high frequency carrier and that he individually adjusted each for perfect performance. I later discovered it was all a lie and the cartridge was a Panasonic strain gauge with a decent electronics package. When I called him on it and was about to go to print he went silent. But he was quite the character anyway.
The -128 dB story may be possible if the jitter frequency is 3 KHz and the "carrier" is 18 KHz. Not if the jitter is 120 Hz and the "carrier" is 3 KHz.
I have said before the jitter problem is solved in so many ways but its a great marketing story. Very few people are equipped to measure it and fewer actually do measure jitter. But its mysterious and technical therefor a great story. My first run in with Audio MFR's lying with John Iverson and his magic phono system. He claimed it had a high frequency carrier and that he individually adjusted each for perfect performance. I later discovered it was all a lie and the cartridge was a Panasonic strain gauge with a decent electronics package. When I called him on it and was about to go to print he went silent. But he was quite the character anyway.
The -128 dB story may be possible if the jitter frequency is 3 KHz and the "carrier" is 18 KHz. Not if the jitter is 120 Hz and the "carrier" is 3 KHz.
It was covered earlier in the thread that devices with poor response to clicks & pops make them much louder as they cannot recover. What about a buffer designed solely to be able to take them first to drive a design that can work to reduce them? Seems like a logical place to start. Then the questions about how to limit/reduce them?
Jan, the waveform shown is not TIM30, but it is a DIFFERENTIATED (by using a passive inverse RIAA box (Jung, Lipshitz) and further rolled of by a 6dB/oct 30KHz filter. If I showed the TIM30 waveform, it would resemble a 10us rise-time, 3.18KHz square wave. The TIM(30,30) waveform is much faster than that.
Please Note that in Graph 1, I used an even slower test waveform TIM(15,10) in some measurements to be closer to a typical moving magnet cartridge.
Please Note that in Graph 1, I used an even slower test waveform TIM(15,10) in some measurements to be closer to a typical moving magnet cartridge.
The areas I think they focused on in their literature are those I mentioned. After all, there are only a few sota DAC IC around and so many companies can use it with a characteristic effect/sound. To differentiate would be what you can do all around it. level control (analog/digital etc) , parts selection, opamp type and config, power supplies and filter algor etc.
It is likely in these improved areas they make a point to discuss, is where they made significant upgrades.
In the 3-opamp output stage there may not be removed in the CMR as could be.... so I will remove an R and replace with pot to adjust CMRR to a min or null. Just to see how much better it could be and to listen to any possible changes to sound which could occure.
THx-RNMarsh
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Understandably, there are still some very conventionally skeptical engineers here. Been there too. However, the number of old skeptics maybe decreasing a little, and maybe some new skepticism growing.
For those that tried PMA's recent 24/96 listening test with Foobar ABX, some people discovered they had some statistical tendency towards reverse correlation with the correct answers.
That is to say, they consistently scored more wrong answers than could be accounted for by guessing. It can't have been due to random chance, and they were trying to get the right answers. For those who believe in numbers and science, how could the results be accounted for other than by people's brains hearing something, even if it did not always rise to the level of making it into conscious awareness?
Of the people who discovered they tended towards reverse correlation in Foobar ABX, most probably don't want to be ridiculed as Bybee believers, but at the same time it may be hard for them not to be a little skeptical of prior research results indicating it would be impossible for them to do what they just did in Foobar ABX.
Perhaps they will develop even a little more skepticism of prior hearing research if they find with a little practice they can start to consciously hear some differences in PMA's test files. Or, to start with something a little easier, hearing the differences between a DAC-2 and a DAC-3.
For those that tried PMA's recent 24/96 listening test with Foobar ABX, some people discovered they had some statistical tendency towards reverse correlation with the correct answers.
That is to say, they consistently scored more wrong answers than could be accounted for by guessing. It can't have been due to random chance, and they were trying to get the right answers. For those who believe in numbers and science, how could the results be accounted for other than by people's brains hearing something, even if it did not always rise to the level of making it into conscious awareness?
Of the people who discovered they tended towards reverse correlation in Foobar ABX, most probably don't want to be ridiculed as Bybee believers, but at the same time it may be hard for them not to be a little skeptical of prior research results indicating it would be impossible for them to do what they just did in Foobar ABX.
Perhaps they will develop even a little more skepticism of prior hearing research if they find with a little practice they can start to consciously hear some differences in PMA's test files. Or, to start with something a little easier, hearing the differences between a DAC-2 and a DAC-3.
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