Gentlemen!
I'm afraid You are neglecting a fact that is emerging from this thread here, or rather confirmed again here, because Bernhard keeps on saying for a long time already:
There seems to be NO such a thing like selection grades..
Because what is it, a selection grade?
First, BB had produced a batch of chips, pcm63P. They all are manufactured with the same process, to the same parameters. [there are no military/industrial/commercial grades for these chips]
Then, these were supposed to be MEASURED afterwards by BB, and selected into grades. So, a K grade is such because it had MEASURED better in factory! No other difference between it and a normal P!
Now, the selection criteria, the setup, and the different levels are all well described in the BB documentation.
Now, it happens to be that because of the advances in technology, nowadays we are able to repeat these measurements with our feeble sound cards & other instruments. [bitstream sound cards are having almost perfect low level linearity!]
And for me it's becaming quite clear that MORE persons, in repeatable circumstances, are finding that these measurements are
NOT confirming at all the original factory markings!! If I put a chip in my test set, and it measures bad, it's NOT a K or K2 or whatever grade is stamped on it! That stamp [and the price paid by the tester] is only good for auto-suggestion..
The idea that different production batches can sound different, on the other hand, seems to be perfectly reasonable for me.. for example, the moulded plastic is a totally different quality between my BBJapan and BBkorea chips - the Japan ones are thicker and sturdier.. [but my korea normal P's measure better.. - and sound ~the same, like for PA0SU...]
Edit: to be precise, when I'm saying " a K chip measures bad" does not want to say that it does not comply with the K grade definition - just says that seemingly ALL chips measured up to now are as good or better than K grade - and strangely normal P-s are even better..
Ciao, George
I'm afraid You are neglecting a fact that is emerging from this thread here, or rather confirmed again here, because Bernhard keeps on saying for a long time already:
There seems to be NO such a thing like selection grades..
Because what is it, a selection grade?
First, BB had produced a batch of chips, pcm63P. They all are manufactured with the same process, to the same parameters. [there are no military/industrial/commercial grades for these chips]
Then, these were supposed to be MEASURED afterwards by BB, and selected into grades. So, a K grade is such because it had MEASURED better in factory! No other difference between it and a normal P!
Now, the selection criteria, the setup, and the different levels are all well described in the BB documentation.
Now, it happens to be that because of the advances in technology, nowadays we are able to repeat these measurements with our feeble sound cards & other instruments. [bitstream sound cards are having almost perfect low level linearity!]
And for me it's becaming quite clear that MORE persons, in repeatable circumstances, are finding that these measurements are
NOT confirming at all the original factory markings!! If I put a chip in my test set, and it measures bad, it's NOT a K or K2 or whatever grade is stamped on it! That stamp [and the price paid by the tester] is only good for auto-suggestion..
The idea that different production batches can sound different, on the other hand, seems to be perfectly reasonable for me.. for example, the moulded plastic is a totally different quality between my BBJapan and BBkorea chips - the Japan ones are thicker and sturdier.. [but my korea normal P's measure better.. - and sound ~the same, like for PA0SU...]
Edit: to be precise, when I'm saying " a K chip measures bad" does not want to say that it does not comply with the K grade definition - just says that seemingly ALL chips measured up to now are as good or better than K grade - and strangely normal P-s are even better..
Ciao, George
IY,
Thanks for the comments. Silence is obviously not part of nature, but the sounds of human activity are extremely pervasive. Engine noise from 5-10km distance, Airliners flying by at 10,000m leave a sonic footprint for minutes at a time. The times which you hear only "nature" are very short indeed. That said, the still before dawn can be very, very quite indeed to the point that mic self-noise is dominant.
The "problem" we face with the D1V3 is that each PCM63 is part of a balanced pair. The individual chips within each balanced pair need to be matched closely for noise and linearity, if the procedure followed by Pass Labs in the original D1 is any indication. Even with testing I don't know what criteria the matching should be carried out on. The noise floors are very similar so that shouldn't be a big issue. But the question is what is the best combination of harmonics? Low peaks, but on different harmonics would seem to mean a larger number low peaks, or should we be trying to match chips with peaks on similar harmonics? If THD does reflect non-linearity it would seem that similar harmonic "signatures" would make a better match than simply looking for the lowest peaks. Bear in mind that 12 chips leads to a rather large number of combinations - in the hundreds, if not thousands. More than I have the time to sit and audition.
The only definite indicator I've seen so far on audio performance of the PCM63's is the level of the noise floor. It might not be that surprising that noise floor is significant, given that the BB specs for the different grades are THD+N, not THD alone.
cheers
Paul
Thanks for the comments. Silence is obviously not part of nature, but the sounds of human activity are extremely pervasive. Engine noise from 5-10km distance, Airliners flying by at 10,000m leave a sonic footprint for minutes at a time. The times which you hear only "nature" are very short indeed. That said, the still before dawn can be very, very quite indeed to the point that mic self-noise is dominant.
The "problem" we face with the D1V3 is that each PCM63 is part of a balanced pair. The individual chips within each balanced pair need to be matched closely for noise and linearity, if the procedure followed by Pass Labs in the original D1 is any indication. Even with testing I don't know what criteria the matching should be carried out on. The noise floors are very similar so that shouldn't be a big issue. But the question is what is the best combination of harmonics? Low peaks, but on different harmonics would seem to mean a larger number low peaks, or should we be trying to match chips with peaks on similar harmonics? If THD does reflect non-linearity it would seem that similar harmonic "signatures" would make a better match than simply looking for the lowest peaks. Bear in mind that 12 chips leads to a rather large number of combinations - in the hundreds, if not thousands. More than I have the time to sit and audition.
The only definite indicator I've seen so far on audio performance of the PCM63's is the level of the noise floor. It might not be that surprising that noise floor is significant, given that the BB specs for the different grades are THD+N, not THD alone.
cheers
Paul
Don't wait! Go and measure it NOW!
???
George, what you are saying is that BB is Bull_ _ _. Well, I can’t help with this
I think we got to the point, gentlemen !!!!!!!!!!!!!!!!
It is all about measurements, isn't it? Really, I completely agree, seriously & I am not cynical!!!
Therefore, for all who wish to be perfectly correct, systematic & scientific approval: There are certain measurements that should be taken on the ear dram!
Sorry, but as I learned in this thread, it is not about being too emotional about things. Just to be scientific, Ok? To your system.
So it is about MEASURMENTS and one should not wait too long!! Here one can’t exchange a Chip if he is too late and no selection grade will be of help
Then we talk
Greetings, IY.
Joseph K said:
???
George, what you are saying is that BB is Bull_ _ _. Well, I can’t help with this
I think we got to the point, gentlemen !!!!!!!!!!!!!!!!
It is all about measurements, isn't it? Really, I completely agree, seriously & I am not cynical!!!
Therefore, for all who wish to be perfectly correct, systematic & scientific approval: There are certain measurements that should be taken on the ear dram!
Sorry, but as I learned in this thread, it is not about being too emotional about things. Just to be scientific, Ok? To your system.
So it is about MEASURMENTS and one should not wait too long!! Here one can’t exchange a Chip if he is too late and no selection grade will be of help
Then we talk
Greetings, IY.
Paul,
You can surely do it by listening. It will start indeed randomly, but quite very fast - you will eliminate the several chips you dislike.
At second and third listening tests, you might come to result faster then you think. Several of the PCMs should sound still very similar.
It is also a question of how much time you can invest.
Once you choose them by listening
it will be even more fascination to... measure them later.
Good luck & Greetings.
You can surely do it by listening. It will start indeed randomly, but quite very fast - you will eliminate the several chips you dislike.
At second and third listening tests, you might come to result faster then you think. Several of the PCMs should sound still very similar.
It is also a question of how much time you can invest.
Once you choose them by listening
it will be even more fascination to... measure them later.Good luck & Greetings.
IY,
I had a listen on headphones (sennhieser hd-280 pros) to single chips while running the 997hz sine waves. Again it's difficult to compare chips due to the need to power down, then remove, insert and power up, but it did seem that chips with high HD sounded less pure than those with low HD. Did a quick compare of a couple of chips with the opening track from Herbie Hancock's Mwandishi cd. The chip with highest HD and slightly higher noise floor seemed to obscure some detail of a soft bass clarinet note near the start of the track and trumpet notes had a slightly abrasive edge when compared to the best of the new chips. The difference in noise floor is at most 1-2dB.
I'll use the tests to narrow down the selection, but I will give the rejects a listen to confirm the tests.
cheers
Paul
I had a listen on headphones (sennhieser hd-280 pros) to single chips while running the 997hz sine waves. Again it's difficult to compare chips due to the need to power down, then remove, insert and power up, but it did seem that chips with high HD sounded less pure than those with low HD. Did a quick compare of a couple of chips with the opening track from Herbie Hancock's Mwandishi cd. The chip with highest HD and slightly higher noise floor seemed to obscure some detail of a soft bass clarinet note near the start of the track and trumpet notes had a slightly abrasive edge when compared to the best of the new chips. The difference in noise floor is at most 1-2dB.
I'll use the tests to narrow down the selection, but I will give the rejects a listen to confirm the tests.
cheers
Paul
Paul,
This confirms what we would be expecting.
I am using about 6 different CDs when listening & testing. Almost no 1 CD can give all details. This is quite obvious when one knows how things are being done in a studio recording, even if recorded right (let's say also according with Bob Katz excellent explanations, and thanks for this info as well).
Sometime, adding just 0.25 ms to the hall ambiance (!) will take Trumpets sharpness out, which will also mask the sound a bit. But, noise floor must be completely removed, by all means. 1-2 db difference can make it, for sure.
Loosing the clarinet sound should happen indeed above the hall noise level. We can't do more then this. I told once the Clarinettist Giora Feidman to please not go under 7 levels of "PP" (ppppppp - and it is only an illustration of course) - because I was loosing him under the Hall's never-heard-there-before air conditioning system, and I am talking about a major hall in Berlin.
I would really think that one should try using your own birds recording as well, assuming that you managed to record it full range, high resolution and to the level of Mic. noise.
p.s. 1:
As for "I'll use the tests to narrow down the selection, but I will give the rejects a listen to
confirm the tests" - this would be excellent; looking forward to your report, accordingly.
p.s. 2: Just pop to my mind: One of the greatest advantageous of the "Y" (against the "K") was that what you said about Trumpets and Clarinets (!). If the "K" should it to be somehow compressed by the dynamic, with loosing Clarinet softest and suffering from Trumpets harsh highs, my "Y" are able to handle all this correctly. So there must be more Dynamic Range and Headroom available through using them.
Regards,
This confirms what we would be expecting.
I am using about 6 different CDs when listening & testing. Almost no 1 CD can give all details. This is quite obvious when one knows how things are being done in a studio recording, even if recorded right (let's say also according with Bob Katz excellent explanations, and thanks for this info as well).
Sometime, adding just 0.25 ms to the hall ambiance (!) will take Trumpets sharpness out, which will also mask the sound a bit. But, noise floor must be completely removed, by all means. 1-2 db difference can make it, for sure.
Loosing the clarinet sound should happen indeed above the hall noise level. We can't do more then this. I told once the Clarinettist Giora Feidman to please not go under 7 levels of "PP" (ppppppp - and it is only an illustration of course) - because I was loosing him under the Hall's never-heard-there-before air conditioning system, and I am talking about a major hall in Berlin.
I would really think that one should try using your own birds recording as well, assuming that you managed to record it full range, high resolution and to the level of Mic. noise.
p.s. 1:
As for "I'll use the tests to narrow down the selection, but I will give the rejects a listen to
confirm the tests" - this would be excellent; looking forward to your report, accordingly.
p.s. 2: Just pop to my mind: One of the greatest advantageous of the "Y" (against the "K") was that what you said about Trumpets and Clarinets (!). If the "K" should it to be somehow compressed by the dynamic, with loosing Clarinet softest and suffering from Trumpets harsh highs, my "Y" are able to handle all this correctly. So there must be more Dynamic Range and Headroom available through using them.
Regards,
irgendjemand said:Herb,
If I do understand you right, you mean that by “re-clocking” the DAC, you arrived a level where the PCMs having no any notable "character". I have no idea how this can be!!!
Another question: When you say "my best PCMs" do you mean - by measuring or by listening?
The LATCH to the PCM (and any other DAC) is the only important signal that should be 'jitter-free'. To obtain this you should also be aware of cross talk between the other signals and the LATCH-signal, especially the data-signals because they CHANGE WITH THE AUDIO !
Most SPDIF-receivers and/or digital filters suffer from cross talk and other idiosyncrasies (apart from the filter algoritm) by which they sound different from each other if they are connected directly to the DAC-chip.
If you reclock the digital- (clock and latch) and audio signals decently, only the digital filter ALGORITM will remain important.
The reclocking is also important to avoid cross talk and other differencies at THE INPUT-side of the PCM !!!! I THINK (I can not proof it up till now) that the diferent production runs (in different countries, at different times) of the PCM's are different in this aspect. (The silicon chip inside has just been copied or have been delivered from the stock of BB). Reclocking just before the PCM on a well designed PCB with a low jitter clock is the solution to all these problems.
What remains is the distortion within the PCM during DA-conversion which we all are talking about and measuring (in different ways). My statement is that this (little) distortion is of secondary importance.
My recent selection of the PCM's (my best PCM's) has been executed on the base of this distortion......
spzzzzkt said:
I worked with Philips for more than 30 years, so I'm familiar with mass-production. You should always be prepared for mistakes during production, which means that you should build in the possibility to LOCALIZE the faulty position.
For this reason the machines which mold the plastic around the circuit give their signature on it !!! Using this signature to select the ELECTRONIC behaviour of components will be rather silly. Silicon chips from the same wafer (what everybody will like to have, because they are clones of each other) DO HAVE DIFFERENT MOLDING MACHINE SIGNATURES.
Herb,
This is an excellent explanation, thank you!! I will have to find time and then - to "jump" to Tent-Labs (only 280 KM). Re-clocking the DAC (clock and latch) while avoiding cross talk sounds very plausible to me.
This is for me THE question: Are we talking indeed about "small" distortion levels, or - something more major includes a lower noise-level of the PCM, or both. According to your mail (& George's one) there is no difference to be heard once all is being clocked correctly. I do doubt THIS.
However, if this is true
I will have to eat my hat 
No problems
Until clocking the DAC, please give my best regards to Guido T. tomorrow at Den-Haag...
This is an excellent explanation, thank you!! I will have to find time and then - to "jump" to Tent-Labs (only 280 KM). Re-clocking the DAC (clock and latch) while avoiding cross talk sounds very plausible to me.
PA0SU said:
This is for me THE question: Are we talking indeed about "small" distortion levels, or - something more major includes a lower noise-level of the PCM, or both. According to your mail (& George's one) there is no difference to be heard once all is being clocked correctly. I do doubt THIS.
However, if this is true
I will have to eat my hat No problems Until clocking the DAC, please give my best regards to Guido T. tomorrow at Den-Haag...
irgendjemand said:Herb,
I am not an engineer, so I base my knowledge on a combination of what I read, see and mostly – what I hear. Readings your page, there are several topics to be discussed, for example - about the using of a loudspeaker membrane (in the HF) with having no cabinets (?!). There is also the Cables issue & the ESL, and and...
My own experience shows, that every step/measure which I took in my HiFi system – did influenced the sound, in one way or another: Sometime the sound differences were not such major,
......
QUOTE]
That is the difficulty: what is SCIENCE and what is RELIGION..... You can find 'everything' on the Interenet and audio magazines. The most is religion: People BELIEVE in terms as 'oxygen-free-copper' and such rubbish. I am a scientist and I KNOW that it is very difficult to find the relevant parameters for better sound.
Often folks measure variables which have little to do with the sound quality and 'forget' the variables of interrest. I don't want to discuss the subject here but read the Internet about loadspealer cables and interlinks...... !! Read also the article:
23. EMC Problems with Audio Equipment
on my web site. I found out that the kind of cord for speaker cables becomes irrelevant if the system is EMC (Electro Magnetic Compatible). The same counts for interlinks.
Sometimes I am threaten by commercial people who sell speaker cables for the price of 500 euro per meter when I demonstrate on an exebition an excellent sound system with ordinary cables and old standard interlinks with DIN-plugs, etc.!!
I do not know if you are familiar with electro static loudspeakers (ESL) The 'mambrane' as you call it is one of the subjects in this world. I have found a much better material for this.
ESL's are dipole loudspeakers so they are NOT enclosed in a cabinet....
Enough for here..... Do not waste your effort in changing the wrong parameters.
PA0SU said:
Very good news!
So I will surely not have to eat my hat, even before re-clocking
But if so, what is all this about swapping and that PCMs "sound the same" ??
p.s It seems that our thread here is still very much OK, especially if one read something like this in another thread:
Well gentlemen, we are doing not so bad!!!!
Greetings!
irgendjemand said:Herb,
This is an excellent explanation, thank you!! I will have to find time and then - to "jump" to Tent-Labs (only 280 KM). Re-clocking the DAC (clock and latch) while avoiding cross talk sounds very plausible to me.
This is for me THE question: Are we talking indeed about "small" distortion levels, or - something more major includes a lower noise-level of the PCM, or both. According to your mail (& George's one) there is no difference to be heard once all is being clocked correctly. I do doubt THIS.
However, if this is true
Until clocking the DAC, please give my best regards to Guido T. tomorrow at Den-Haag...
The small haronic distortion AND the low noise floor of our DACs are NOT the problem. Look at www.tentlabs.nl and you will find a DIY CD player for a 2400 euro or about which sounds excellent!!!! In this player also the cheepest 1742 (?? I'm not sure) DACs are implemented, because Guido knows that the change in quality is not noticable with more expensive ones.
PA0SU said:
Tentlabs page www.tentlabs.com is very interesting indeed. I went through it several times and I am sure that the products are very good.
As for the rest of the post - I completely do not agree.
Quote
Please do not attribute this nonsense to me, I said nothing of the sort. You asked what the chips marking were and I explained. The markings are a convenient means to identify the chips while testing and nothing more.
Unquote
I asked you for the meaning of the codes AT THE TOP of the chips and gave you an example like:
9441 K4 035
and you reply with the codes from the bottom......... which say NOTHING about the silicon inside. You can only use that code FOR YOURSELF. Any correspondence with that bottom code on itself is meaningless. The COMBINATION of the code on top and the bottom code COULD, once again: COULD be an indication, but be careful.
Please do not attribute this nonsense to me, I said nothing of the sort. You asked what the chips marking were and I explained. The markings are a convenient means to identify the chips while testing and nothing more.
Unquote
I asked you for the meaning of the codes AT THE TOP of the chips and gave you an example like:
9441 K4 035
and you reply with the codes from the bottom......... which say NOTHING about the silicon inside. You can only use that code FOR YOURSELF. Any correspondence with that bottom code on itself is meaningless. The COMBINATION of the code on top and the bottom code COULD, once again: COULD be an indication, but be careful.
PA0SU said:
Let's leave it like this. I easily hear the differences between the PCMs, what can I say? Indeed, my DAC is not yet separately "clocked", but all in all it is an amazing DAC, very accurate. Modification started in 1997 and we are now in 2008. OK, I will invest in a clock for being even more coherent. Now, other members here who ARE using good re-clocking systems (like Paul) or - a low Jitter Receiver (Spencer, with the DIR 9001) are reporting major changes between PCMs sound. So it is not about a clock, of course not.
Moreover, Bernhard said once (if I remember right) that the better the DAC is – the better the differences should be heard. Guido mentioned once that things must be transparent and we agreed about this - but you insist that exchanging PCMs - even between CDPs (!) makes no difference or it is a marginal subject. OK, what can I say? Better we leave it like this. Or one hear it - or not. Meeting & listening together to music will not change this impression, very probabely. We hear what we hear.
Greetings.
All, My logic of improvement is very simple.
Changing from CS8412 to 8414 only have very little difference but changing to DIR9001 is a very obvious improvement.
Changing from Taiwan PK to Japan PK PCM63 chips is very obvious improvement but changing from PK to K2 or Y is not that much improvement.
Changing my transport from a Marantz DV7600 (has been using for 3 yrs) to CD-PRO2 (diy) transport is a obvious improvement
Changing the regulator from 78 series to LM337/217 do have little improvement on the D1.
Changing the layout of the D1 from V2 to V3 do have quite significant improvement.
Changing capacitor from normal grade to Black Gate will have .....
Too many things to list.... but also changing our ears also will be different, can be worst and can be better!
BUT NOT ALL THE CHANGS WILL GIVE YOU BIG IMPROVEMENT AND SOME CHANGE IS JUST MAKE IT SOUND DIFFERENT AND NOT NECESSARY BETTER!
The question I have is changing from DIR9001 to whatever super low jitter clock, how much is the improvement and how much is the cost? From what I experience so far is not my first priority to improve the clock and I am working on the transport at this moment.
It will be interested to know how much is the improvement in his player if Irgendyernand change the clock to a Tent clock.
For non-diyer, changing the CD player from one model to another model can also be better / worst but how much is the cost and the risk? This is business world and we need to be smart.
Changing from CS8412 to 8414 only have very little difference but changing to DIR9001 is a very obvious improvement.
Changing from Taiwan PK to Japan PK PCM63 chips is very obvious improvement but changing from PK to K2 or Y is not that much improvement.
Changing my transport from a Marantz DV7600 (has been using for 3 yrs) to CD-PRO2 (diy) transport is a obvious improvement
Changing the regulator from 78 series to LM337/217 do have little improvement on the D1.
Changing the layout of the D1 from V2 to V3 do have quite significant improvement.
Changing capacitor from normal grade to Black Gate will have .....
Too many things to list.... but also changing our ears also will be different, can be worst and can be better!
BUT NOT ALL THE CHANGS WILL GIVE YOU BIG IMPROVEMENT AND SOME CHANGE IS JUST MAKE IT SOUND DIFFERENT AND NOT NECESSARY BETTER!
The question I have is changing from DIR9001 to whatever super low jitter clock, how much is the improvement and how much is the cost? From what I experience so far is not my first priority to improve the clock and I am working on the transport at this moment.
It will be interested to know how much is the improvement in his player if Irgendyernand change the clock to a Tent clock.
For non-diyer, changing the CD player from one model to another model can also be better / worst but how much is the cost and the risk? This is business world and we need to be smart.
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