Ceglar,
our experience is mainly related to an Oversampling DAC like the ES9018 while you are experiencing a Non Oversampling DAC like the TDA1541A so what I will say in the next deserves to be furtherly discussed.
We experienced a significant and clearly audible difference switching from a standard technology clock to a thermally controlled clock while we found just a slight difference between 22 MHz and 45 MHz so the first point is that the best improvement is mainly provided by the technology itself rather than by the frequency value.
Talking about an Oversampling DAC like the ES9018 there are two opposing effects:
a) a lower frequency clock shows always a better phase noise w.r.t. an higher frequency clock.
b) the sophisticated dejitter engine of the ES9018 could work better with an higher quantization of the bit clock so higher frequencies could benefit of this effect in opposition to the worst phase noise of higher frequency (I'm not sure about this point, it is just a feeling I got reading the detailed Sabre documentation on their DACs)
Talking about a Non Oversampling DAC like the TDA1541A you have only the effect of the previous point "a)" without the benefits of the point "b)" so I espect you could enjoy more a lower frequency clock. (e.g. 22 MHz should be better than 45 MHz in your system)
Pulsar,
i have a buffalo setup in Mono...currently with the 957 crystek on Ian'Boards, as I said before...2-3 years old this setup. Regs from twisted p. All in asynchronous board as I did not want to desolder the clock from the buffalo boards at that time...
So, what would be my best options ? What do you recommend regarding best bamg for the buck / work-effort / complexity of mod if you would suggest 3-4 option from a strong start to the ultimate solution, specifically for the BIII in Dual mono ?
THX
Frank
i have a buffalo setup in Mono...currently with the 957 crystek on Ian'Boards, as I said before...2-3 years old this setup. Regs from twisted p. All in asynchronous board as I did not want to desolder the clock from the buffalo boards at that time...
So, what would be my best options ? What do you recommend regarding best bamg for the buck / work-effort / complexity of mod if you would suggest 3-4 option from a strong start to the ultimate solution, specifically for the BIII in Dual mono ?
THX
Frank
A two cents question to PulsarClock please, maybe totaly off topic (may you excuse me Ian for that if it is !)
- Do you provide just the clock or also a standalone pcb to feed it (does the thermal controll needs an other aditional supply than the standalone one Ian's board provides for its Si crystal ?)
-have you such crystals which can works with higher frequencies for FGPA devices like which can be programmated about speed clock ? I think about Soekris DAC e.g.)
- does this technology needs an factory ageing to stabilize the frequencies before to be sold ?
- Due to the RF and high speed if we talk about the new clock V2 from Ian : is it simple to swap its clock SI ref by yours on him pcb ? If an external pcb clock to feed the Ian's pcb : should you advise a max speed clock due to the splitted layout and problems than RF intoduces in such high speed designs ?
To rephrase it : does it needs a SOTA Power supply to use your SOTA clock, at least do you provide shematics to do it or have an avaliable reference PS shematic with which you tested the Pulsar clock on the ES9018 DAC ?
Sorry if two cents,I have no technical background nore I read this thread, just hear than japanese diyers seems to use both your clock and the Ian's boards together with good results (without knowing really the frequency they use ! Are they NOS or x2 max... this is Japan ?!).
regards
- Do you provide just the clock or also a standalone pcb to feed it (does the thermal controll needs an other aditional supply than the standalone one Ian's board provides for its Si crystal ?)
-have you such crystals which can works with higher frequencies for FGPA devices like which can be programmated about speed clock ? I think about Soekris DAC e.g.)
- does this technology needs an factory ageing to stabilize the frequencies before to be sold ?
- Due to the RF and high speed if we talk about the new clock V2 from Ian : is it simple to swap its clock SI ref by yours on him pcb ? If an external pcb clock to feed the Ian's pcb : should you advise a max speed clock due to the splitted layout and problems than RF intoduces in such high speed designs ?
To rephrase it : does it needs a SOTA Power supply to use your SOTA clock, at least do you provide shematics to do it or have an avaliable reference PS shematic with which you tested the Pulsar clock on the ES9018 DAC ?
Sorry if two cents,I have no technical background nore I read this thread, just hear than japanese diyers seems to use both your clock and the Ian's boards together with good results (without knowing really the frequency they use ! Are they NOS or x2 max... this is Japan ?!).
regards
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Well, I gues I am as well asking myself, what the best usage of the clock is...only in Ian's board and if so, can it simply replace the crytek without any mod, even though this is the board version of 2-3 year ago when it came out (not sure if there is already a new version)...or not on Ian's board, but on the Biii ? Hmmm...And is synchronized mode mandatory as the traditional clock of the biii would otherwise mess up the jitterfree signal coming from the pulsar/ian board...?
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Thank you for the reply. I am thinking the lower speed clock should be sufficient, given (and although the 1541A will work at higher sampling rates than 176/192) the layout of the 1541A PCB (presumably) wasn't designed to operate at sampling rates higher than this (for what its worth).
Its nice to know that your clock modules will plug straight into Ians Dual XO board as is - and be happy fed with the on-board LDO reg, and also that you make available a dedicated low noise supply for your clocks through your website, which can run the clock/s direct at Ians XO board with some minor modification as documented elsewhere.
I'm getting closer, just waiting for the Euro $ to tank
shouldn't take too long given recent developments Sincerely,
Shane
Dear Ian,
Can I please ask, with your current Dual XO Board, does single or double speed mode have any effect on the jitter output of the I2S signal.
Additionally, if half the Dual XO Board is used single speed, and the other half in double speed (as per jumpers) would this change anything to the above scenario?.
And would it be correct to assume the answer for all WRT to your Dual XO Board would be consistently the same regardless of clock speed and clock technology.. be it generic or a really nice OCXO
Thank you, Ian. I can appreciate that you are busy, and maybe this might suit as an addition to your wiki if deemed appropriate.
Sincerely,
Shane
Can I please ask, with your current Dual XO Board, does single or double speed mode have any effect on the jitter output of the I2S signal.
Additionally, if half the Dual XO Board is used single speed, and the other half in double speed (as per jumpers) would this change anything to the above scenario?.
And would it be correct to assume the answer for all WRT to your Dual XO Board would be consistently the same regardless of clock speed and clock technology.. be it generic or a really nice OCXO
Thank you, Ian. I can appreciate that you are busy, and maybe this might suit as an addition to your wiki if deemed appropriate.
Sincerely,
Shane
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Eldam,You can feed the Pulsar clock with the Pulsar power supply,a supply specially made for the clock (ADM7150 very low noise LDO)you can solder it directly on the terminal block of the clock board of Ian,no problem with the cables.
the Pulsar clock are superb clock,I had the opportunity to test it, i make a report in the thread of Pulsar clock this weekend.
Frank,
here are the options in order of rising performance.
1) if you don't want to remove the original BIII clock you can just install better clocks on Ian's board but this improvement is almost completely cancelled because the quality of the BIII output jitter is mainly due to the BIII main clock.
2) a further improvement is an asynchronous configuration with the substitution of the BIII clock with an high frequency lower jitter clock (e.g. a 100MHz clock)
3)the best option is to switch to a synchronous configuration removing the BIII on-board clock and feeding it from Ian's DualXO board with lower jitter clocks via Ian's BIII clock adapter. As you use a dual-mono setup, please, have care to use same lenght cables also for the clocks.
My suggestion is to look for professional support to remove the original clock in case you don't feel safe enough to do it.
Eldam,
in the following the answers to your kind questions
clsidxxl is right in post #3488, even if the Pulsar Clock can be directly installed on Ian's DualXO board without any mod we provide also a dedicate power supply board for improved performance
to obtain the very best performance we don't provide programmable devices, currently are available the standard audio frequencies for synchronous and asynchronous playback.
In audio applications aging is not a key parameter as it is not the long term stability, the benefits of a low phase noise (e.g. a low jitter) clock is maximum since from its installation
we don't have yet information abuot the V2 board power supply, our understanding having a look at the preliminary pcb provided by Ian is that it will be possible and very easy to install any three-pin external regulator board like is already possible on the Si570 Clock Board but on this point we all must wait for Ian's final design.
Due to the very high professional care that Ian puts in his designs we don't expect any problem due to the high frequencies, the board is specifically designed to work at these frequencies. Also the current DualXO is equipped with individual filter on the clock power supply lines.
Clearly better is the power supply better is the clock performance, the Pulsar Power supply is taylored to the Pulsar Clock even if it shows great performance also on analog power lines.
You can find details of our test setup in this post: http://www.diyaudio.com/forums/vend...clock-ultra-low-noise-ocxo-2.html#post4081558
Ian, sorry for this off topic reply, we hope it can in any case be of some help to your V2 DualXO board finishing touch.
in the following the answers to your kind questions
clsidxxl is right in post #3488, even if the Pulsar Clock can be directly installed on Ian's DualXO board without any mod we provide also a dedicate power supply board for improved performance
to obtain the very best performance we don't provide programmable devices, currently are available the standard audio frequencies for synchronous and asynchronous playback.
In audio applications aging is not a key parameter as it is not the long term stability, the benefits of a low phase noise (e.g. a low jitter) clock is maximum since from its installation
we don't have yet information abuot the V2 board power supply, our understanding having a look at the preliminary pcb provided by Ian is that it will be possible and very easy to install any three-pin external regulator board like is already possible on the Si570 Clock Board but on this point we all must wait for Ian's final design.
Due to the very high professional care that Ian puts in his designs we don't expect any problem due to the high frequencies, the board is specifically designed to work at these frequencies. Also the current DualXO is equipped with individual filter on the clock power supply lines.
Clearly better is the power supply better is the clock performance, the Pulsar Power supply is taylored to the Pulsar Clock even if it shows great performance also on analog power lines.
You can find details of our test setup in this post: http://www.diyaudio.com/forums/vend...clock-ultra-low-noise-ocxo-2.html#post4081558
Ian, sorry for this off topic reply, we hope it can in any case be of some help to your V2 DualXO board finishing touch.
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Thanks Pulsar and clsidxxl for your answers
Greater Clock + FIFO seems to worth the effort.
It remains to me to understand as talked above how one can choose its FS frequencies in relation to the RF the pcb DAC layout can manage ! And if the oversampling made by the PC is a valid alternative to lower the crystal speed choice ! As well in relation to the choice Ian did to use higher frequencies with the new crystals....
ABX tests to quantisize the difference with subjective sound quality result !
Greater Clock + FIFO seems to worth the effort.
It remains to me to understand as talked above how one can choose its FS frequencies in relation to the RF the pcb DAC layout can manage ! And if the oversampling made by the PC is a valid alternative to lower the crystal speed choice ! As well in relation to the choice Ian did to use higher frequencies with the new crystals....
ABX tests
to quantisize the difference with subjective sound quality result !Dear Ian,
Following in the same footstep from the question above, please how does the automatic frequency detector works in case of "not near" frequencies so far as jitter re: single and double speed mode in an absolute sense. All to suggest that a test on a generic unit could be not significant, so I am looking for the definitive answer, and feel that it is one that only are probably able to provide - all of course relating to jitter levels at the I2S output for both single and dual speed mode.
With Thanks,
Shane
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There is absolutely no need to remove the onboard clock on the Buffalo. If you don't want to use it, don't power it. This either means removing the ferrite bead feeding the XO on the Buffalo-II, or simply removing the VDD_XO Trident (or other supply) on the Buffalo-III/IIIse. The XO's output will be high-impedance and will not interfere with an external master clock.
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Thank you Brian for your indication, we removed the clock in order to access the three holes under it but indeed there is an easily accessible two pin clock input on BIII and an even more versatile UFL connector on BIII-SE.
My only concern is that I don't thrust the behaviour (the high-Z parameters) of output lines that are not expressly specified for the Power Off condition (the onboard clock). Even if the output line shows an high impedance its parassitic parameters or leakage current could be different from those specified for the nominal power supply levels, maybe very small but not negligible if to that output is connected a very low jitter device.
In any case it worths a trial, I mean that Blitz could connect an external clock not removing the onboard clock and perform this operation for troubleshooting just in case of not satisfactory performance.
My only concern is that I don't thrust the behaviour (the high-Z parameters) of output lines that are not expressly specified for the Power Off condition (the onboard clock). Even if the output line shows an high impedance its parassitic parameters or leakage current could be different from those specified for the nominal power supply levels, maybe very small but not negligible if to that output is connected a very low jitter device.
In any case it worths a trial, I mean that Blitz could connect an external clock not removing the onboard clock and perform this operation for troubleshooting just in case of not satisfactory performance.
Comparing clocks using IR remote control.
On any DAC project that uses one or more clocks having to plug in or solder
the clocks for comparison is time consuming and allows the clocks to cool down.
I am using the Potato Semiconductors PO3B3306A bus switch device
http://www.potatosemi.com/potatosemiweb/datasheet/PO3B3306A.pdf
to switch between 3 pairs of clocks.
Clock select is performed via an micro controller (outputs isolated) with IR remote.
Twistedpear use similar (analoge switch) devices on the BuffaloIIIse to switch the input signals.
Do they introduce jitter ? The data sheet suggests not.
Waiting for some flack here on the jitter front
Ian, Pulsar - any comments ? You guys have the test equipment
Dean.
On any DAC project that uses one or more clocks having to plug in or solder
the clocks for comparison is time consuming and allows the clocks to cool down.
I am using the Potato Semiconductors PO3B3306A bus switch device
http://www.potatosemi.com/potatosemiweb/datasheet/PO3B3306A.pdf
to switch between 3 pairs of clocks.
Clock select is performed via an micro controller (outputs isolated) with IR remote.
Twistedpear use similar (analoge switch) devices on the BuffaloIIIse to switch the input signals.
Do they introduce jitter ? The data sheet suggests not.
Waiting for some flack here on the jitter front
Ian, Pulsar - any comments ? You guys have the test equipment
Dean.
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I'm very sorry that this post is completely off-topic. However, I think audiences of this thread may possibly do such an experiment that requires a high-quality master clock oscillator, ES9018 DAC of synchronous master clocking scheme and a high-quality I2S bit clock signal.
My current interest is achieving "No Bandwidth" play of ES9018 DAC. Within my limited experiments, I have realized the best sound quality of ES9018 DAC chip when I run the chip under "No Bandwidth" conditions.
However, one continuous play period without "unlock" event under the condition is approximately 24 seconds only. I want to obtain a stable play without an unlock for 44.1kHz/16bit sources. That's why I need more information on this diyAudio Forum.
If you are running your ES9018 chip with a master clock 45. 1584MHz and your I2S Bit Clock is fully synchronized to the master clock, you may have a chance to listen a superior "No Bandwidth" sound of 176.4kHz/24bit PCM sources only for 24 seconds without any interruptions.
I will appreciate your commentary posts on ES9018 thread of this forum.
My current interest is achieving "No Bandwidth" play of ES9018 DAC. Within my limited experiments, I have realized the best sound quality of ES9018 DAC chip when I run the chip under "No Bandwidth" conditions.
However, one continuous play period without "unlock" event under the condition is approximately 24 seconds only. I want to obtain a stable play without an unlock for 44.1kHz/16bit sources. That's why I need more information on this diyAudio Forum.
If you are running your ES9018 chip with a master clock 45. 1584MHz and your I2S Bit Clock is fully synchronized to the master clock, you may have a chance to listen a superior "No Bandwidth" sound of 176.4kHz/24bit PCM sources only for 24 seconds without any interruptions.
I will appreciate your commentary posts on ES9018 thread of this forum.
Shane,
the above quoted post and your following posts on this unusual usage of the DualXO with a 22 and a 49 clock pushed us to investigate the behaviour of Ian's board in this condition so we ran a test with a 22 MHz clock in U1 position and a 49 MHz clock in U2 position (tested with both Pulsar Clock and the original clocks provided by Ian). Synchronous output was sent to an ES9018 I2S input as described in this post and we played without any problem 16-44.1, 24-44.1, 24-48, 32-88.2, 24-176.4, 24-96, 24-192 files.
We tested successfully also an 11 MHz clock in U1 position and a 49 MHz clock in U2 position.
In conclusion the DualXO board demonstrates to be very flexible and perfectly performant also when used in these really unusual configurations.
Thanks Mauro,
Are you able to comment on the jitter output (or any other meaningful parameter) of the Pulsar Clock using 22MHz at 176kHz sampling rate with Ians Dual XO in Single Speed Mode (MCK = 128 *Fs) and the 45MHz clock at 176kHz running in Dual Speed Mode (MCK = 256 *Fs) ? -
Again, all using Ians Dual XO Board
Regards,
Shane
Are you able to comment on the jitter output (or any other meaningful parameter) of the Pulsar Clock using 22MHz at 176kHz sampling rate with Ians Dual XO in Single Speed Mode (MCK = 128 *Fs) and the 45MHz clock at 176kHz running in Dual Speed Mode (MCK = 256 *Fs) ? -
Again, all using Ians Dual XO Board
Regards,
Shane
Shane,
if you send the DualXO output data to a NOS DAC the output bit-clock have the jitter of the clock plus a little contibution due to the electronics so a better clock generates a less jittered bit-clock. As far as I can understand by the DualXO board Single and Double Speed modes shouldn't impact the jitter in different ways. In your example 22 MHz performs better than 45 MHz.
Oversampling DACs could have a different behaviour due to further data processing based on higher MCLK that is not used by NOS DACs.
if you send the DualXO output data to a NOS DAC the output bit-clock have the jitter of the clock plus a little contibution due to the electronics so a better clock generates a less jittered bit-clock. As far as I can understand by the DualXO board Single and Double Speed modes shouldn't impact the jitter in different ways. In your example 22 MHz performs better than 45 MHz.
Oversampling DACs could have a different behaviour due to further data processing based on higher MCLK that is not used by NOS DACs.