I am a Finney believer but I would not be a CLOCK believer for certain brand.
I am also a technology believer.
Beware that Technology may not always bring us better products and we should be smart to make the right choice without spending too much.
Recently I buy a notebook but it come with Vista but actually I want to use XP because I can have faster speed under XP and also will not make my many hardware or software obsolute immediately. Too sad that it is a commercial world and sometimes we have no choice!
For my hifi, I know I have total choice on that and I have my freedom to believe in religion also!
I am also a technology believer.
Beware that Technology may not always bring us better products and we should be smart to make the right choice without spending too much.
Recently I buy a notebook but it come with Vista but actually I want to use XP because I can have faster speed under XP and also will not make my many hardware or software obsolute immediately. Too sad that it is a commercial world and sometimes we have no choice!
For my hifi, I know I have total choice on that and I have my freedom to believe in religion also!
To the attention of the "Finney believers":
He was talking about the superiority of the DDS approach.
Have a look at it yourself.
Here it is attached [again] the phase noise of the clock by PA0SU:
Look at the smoothness [no spuries at all] and the level at 100 Hz [-140dB]
He was talking about the superiority of the DDS approach.
Have a look at it yourself.
Here it is attached [again] the phase noise of the clock by PA0SU:
Look at the smoothness [no spuries at all] and the level at 100 Hz [-140dB]
And here it is the same for a DDS chip, [AD 9834 at 2MHz with 50MHz clock] which is considered good - that is, in practice one can get even worse. Look again at the level at 100 Hz..
The attachment comes from this thread:
http://recforums.prosoundweb.com/index.php/t/22929/0/#msg_num_7
Decide for yourself, which is the "dated and surclassed" approach..
Ps.: The fact that this latter graph was taken at 2MHz carrier, and the Rutgers osc. is at 11.28 MHz carrier, gives an advantage of ~6 times for the AD9834! That is, if it looks like that at 2MHz, at 11 MHz would look ~6 times worse [higher noise]!!
The attachment comes from this thread:
http://recforums.prosoundweb.com/index.php/t/22929/0/#msg_num_7
Decide for yourself, which is the "dated and surclassed" approach..
Ps.: The fact that this latter graph was taken at 2MHz carrier, and the Rutgers osc. is at 11.28 MHz carrier, gives an advantage of ~6 times for the AD9834! That is, if it looks like that at 2MHz, at 11 MHz would look ~6 times worse [higher noise]!!
Attachments
Joseph K said:
It is even worse! Each doubling in frequency adds 6 dB to the noise. From 2 to 11.3 Mhz adds about 15 dB, so my clock would give -140 dBc/Hz - 15 dB = -155 dBc/Hz at a distance of 100 Hz with 2 MHz carrier.
I do not understand why, but reclocking the signals between digital filter and PCM63 with my clock yields a much better audio. The perception of the human ear is mysterious. Sometimes one can measure large differencies (eg. distortion) without much harm for the audio and the another hardly or not measurable change yields a clear enhancement.
I think that this is one of the reasons that audio-religions appear. Commercial people abuse the less technical people and sell them speaker cables of more than $1000 per meter......
Joseph and Herb,
I cannot understand all this but I want to know what is the impact of -111db, -122 db, -133db or -144db jitter noise to the final result of DAC conversion. I need to have some benchmark to know what is good enough, what is best, what is not necessary.
To be more pratical, how much is enough and what is the norm in Pro-Audio equipment? There must be a reference point.
To me many good sounding equipment do not use excellent perfromance clock but it is a total system design make the equipment sings.
Just telling me you are expert in clock is meaningless as you must also be good in other part of the system.
Just tell peole to use a Branded clock is nonsense to me as they also need a good CD, good recordings, good transport, good amp, good speaker, good environment etc... and also good ears.
Can you give us all the details to build a good clock? Dont just give a block diagram and it is not enough to change the mosque into a University!!
Learn from Nelson Pass to provide all the details and advise. I am also a NP believer. A believe to share knowledge but not just talk the way like a marketing guy and try to sell something here and there.
I cannot understand all this but I want to know what is the impact of -111db, -122 db, -133db or -144db jitter noise to the final result of DAC conversion. I need to have some benchmark to know what is good enough, what is best, what is not necessary.
To be more pratical, how much is enough and what is the norm in Pro-Audio equipment? There must be a reference point.
To me many good sounding equipment do not use excellent perfromance clock but it is a total system design make the equipment sings.
Just telling me you are expert in clock is meaningless as you must also be good in other part of the system.
Just tell peole to use a Branded clock is nonsense to me as they also need a good CD, good recordings, good transport, good amp, good speaker, good environment etc... and also good ears.
Can you give us all the details to build a good clock? Dont just give a block diagram and it is not enough to change the mosque into a University!!
Learn from Nelson Pass to provide all the details and advise. I am also a NP believer. A believe to share knowledge but not just talk the way like a marketing guy and try to sell something here and there.
Spencer,
The only one who is trying to advertise a product here is Finney. You had put up a link to that product.
I had not sold a single thing on Diya, ever. I'm a diyer of the purest construction. The "rutgers osc" to which I referred here, is a purist diy project as well. It can be coined up in an afternoon, exactly like a Kwack clock. PA0SU has all the documentation on his website, public. I think he put even here the pdf of his oscillator.
Of course, PA0Su only had provided the basic thinking and the fine little tricks for the construction of a really low noise osc. It's not a documented product for sale, with pcbs and idiot proof users guide. I thought Diya is supposed to be a "do it yourself" forum, maybe I'm in the wrong?
Then, you are absolutely right in saying that it's not enough for a good end product. And there are many things that has influence on the final result.
But if we do not try to isolate the problems first, we will not get anywhere. And here it is why I'm speaking up now: I feel that Finney mucked up / confused a lot of things, where the technical bases are instead rather clear. A good clock has lower phase noise.
If someone advertises a solution which, instead, has something like 60dB more, that is, 1000 times more, ONE THOUSAND times more noise, than it has to be for other reasons.. like better adaptability for all type of frequencies, with the same chipset.. - that is, lower production costs - that is, marketing...
Ciao, George
The only one who is trying to advertise a product here is Finney. You had put up a link to that product.
I had not sold a single thing on Diya, ever. I'm a diyer of the purest construction. The "rutgers osc" to which I referred here, is a purist diy project as well. It can be coined up in an afternoon, exactly like a Kwack clock. PA0SU has all the documentation on his website, public. I think he put even here the pdf of his oscillator.
Of course, PA0Su only had provided the basic thinking and the fine little tricks for the construction of a really low noise osc. It's not a documented product for sale, with pcbs and idiot proof users guide. I thought Diya is supposed to be a "do it yourself" forum, maybe I'm in the wrong?
Then, you are absolutely right in saying that it's not enough for a good end product. And there are many things that has influence on the final result.
But if we do not try to isolate the problems first, we will not get anywhere. And here it is why I'm speaking up now: I feel that Finney mucked up / confused a lot of things, where the technical bases are instead rather clear. A good clock has lower phase noise.
If someone advertises a solution which, instead, has something like 60dB more, that is, 1000 times more, ONE THOUSAND times more noise, than it has to be for other reasons.. like better adaptability for all type of frequencies, with the same chipset.. - that is, lower production costs - that is, marketing...
Ciao, George
spencer said:
Up till now I THINK that when I could build a better clock, that I could get a better performance WITH MY SYSTEM. I THINK that the noise close to the carrier harms most, so under 100 Hz.
What does a better clock do if 'the rest of the system' is on level?
The depth and difinition (even in the hight!!!!) of the stereo image enhances and the sound is as the nature after a shower of rain. No more and no less.
The best clock is still not good enough, but I agree: my PCM-7010 DAT has an overall performance which is good in spite of the clock with a jitter of over 100 ps.............
Sure!
Of course the rest of the system should be on the same level and the knowledge of this rest should be developed as well, but here starts the problem: You have only to know which things are essential and to know these essentials takes years of education and research..........
I could not say it better.......
Read the article: 14. Reproducible Low Noise Oscillators. on my web site.......
This is what I try to do all the time, but I cann't educate people 'on a distance' moreover because they donn't want to be educated. On Internet is no hierarchy so everybody can say: 'Listen, I will tell you the truth'
For now the only way is: read my articles (most of them are in Dutch, sorry) on my web site and try to form yourself an idea of my technical background. If you cannot judge the articles because of lack of technical background, then I can not say any thing more to convince you.................
Re: "Rutgers Osc"
This means that you:
- cannot read
- have no bloody idea of electronics.
I offer you the essentials of a good, reproducible oscillator and you are asking for power supply details........ If you can not solve this problem yourself, then you could better NOT build my oscillator because the lay out will be a problem as well and after some days you are telling here that my oscillator does not work!
Please keep off your hands of it.
QSerraTico_Tico said:
This means that you:
- cannot read
- have no bloody idea of electronics.
I offer you the essentials of a good, reproducible oscillator and you are asking for power supply details........ If you can not solve this problem yourself, then you could better NOT build my oscillator because the lay out will be a problem as well and after some days you are telling here that my oscillator does not work!
Please keep off your hands of it.
tritosine said:
Yes, all the possibilities! One day I was discussing this with a few friends about moving cross-over to the DAC, this digital crossover thing. Basically it's like the Behringer DCX2496 done in the DAC yet without the extra AD/DA stage. Based on what Emerald Physics can do to their speakers with the Behringer. I am confident a DAC/crossover can do even more than that!
An externally hosted image should be here but it was not working when we last tested it.
irgendjemand said:
Connection? Who? Me? Well, sort of. I am a forum raider, popping up everywhere in the world so you can say that I have connection to everyone! 😀
Be honest, I do not know this guy who did the I2S interface. This interface is for the output of transport. It does reclocking on the I2S signal, feeds the signals to output driver, that.s it. It uses Cat6 network cable for the transmission.
To use it, you can put a good XO on the board then use it for the transport's main clock. Or you can use the drives master clock to do the reclocking. On the receiver side, you have to do the work youself. Probably do signal reshaping first then do some sort of reclocking. There's only one clock used hence less headache.
From the photo I can see that the implementation looks ok, not the best yet worth of a try.
I am trying to get the same I2S board as well. Communication is easy for me yet sending money to China is a big turn-off. I am also interested in this AD1955 board. It has the I2S receiver already built on board. The DAC may look impressive yet I figure the sound probably is just OK. Nice to have for my collections though.
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Nikola Krivorov said:
Well, if you want to do a group-buy the definitely I can translate/forward the message for you. Still, I think many people can help you on that already. 🙂
Joseph K said:
This is funny that someone who has been selling things on diyaudio.com for years is accusing me that I am selling stuff here. The fact is that The FIFO/DDS board is long gone and I even dont know the designer of the I2S thing. Are you getting nervous that someone is trying to promot something different from what you have selling here? Oh, yes, I remember that you have been selling this master clock solution with fiber optics thing! 😀
Have you ever read Paul's post at all? He has a problem. He did this reclock thing and the clock frequency kept jumping. I was just telling him that he needed a FIFO there to smooth things out. Since a FIFO is involved, he also has to consider taking care of the overflow and underflow issue. Simple. This is his EXPERIENCE and I was reacting to it. Isnt this experience counted as real experience based on your standard? 😀
The way you talk about experiences just show me your arrogance and your contempt to other peoples experiences!
Some people design for general scenario, some prefer to cover the worst case scenario. I am the buyer for the latter case. In fact, most engineers will go for the latter.
2 word buffer is enough? So how come the aforementioned Genesis digital lens failed miserablely? Probably that experience has never reached the domain of your experience? So the small buffer in DIR9001 is no good and your 2 word buffer works just fine?
Now that's REAL experience! 😀
Again, you are acting silly. Not even mention the way you jump to the conclusion too quickly and start to accuse people. How arrogant and ignorant you are!
These are the only photos I can find so what else I can do? Shall I use Photoshop to remove the link before I post the picture? Now I feel lucky that those photos do not contain links to some porno site or you might to start to call me a porno seller! Haha.
tritosine said:
I am not sure whether that I2S thing works for your Lynx. Too much hassle involved. Probably a word clock solution will be better?
Joseph K said:
Nice little chart? So what?
You can show me all kinds of graphs for a component. They are good to have, nice as reference points. Yet what really counts is how the component behaves in a real circuit, in a real application. That's the real measurement you care about.
Again, as I have said, the application is that you have this PIC-DAC-VCXO loop thing. For this circuit, a DDS can be used to replace DAC/VCXO as a cleaner DPLL solution. It's less hassel, works better. People invented DDS for a certain reason, OK?
Also, looks like the DDS test wasnt done right? 50MHz XO? For the output frequency, 50MHz is not enough. Not even mention it's hard to get a decent 50MHz XO.
Audio Precision II is using DDS. Apogee Big Ben is using DDS, the list goes on and on. Those engineers must be very dumb? They all have to come down here to buy your gadets, right? 😀
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