Hey EC Designs
Hi EC
It is never pleasant to be on the end of a tar and feathering I know but i have always been happier to be out on the limbs i choose to be on rather than mainstream.
You have been open and transparent with this whole design and you have a great belief in your project.
Get up. dust yourself down and walk proud... Einstein was ridiculed as was copernercus and why? Because they dared walk outside the constraints of conventional wisdom.. well no new fronteirs are ever discovered by staying close to land. You must beleive ,as you do I am sure, in yourself. Dont worry about the critics.. if you posed no threat to them they wouldnt bother now would they
Keep up the good work
As soon as your kit is ready i will build one.. this is all over my head but I recognise genius when I see it.
Now put your mouthguard back in and get back in the ring..
Regards
Nick Mega
Australia
Hi EC
It is never pleasant to be on the end of a tar and feathering I know but i have always been happier to be out on the limbs i choose to be on rather than mainstream.
You have been open and transparent with this whole design and you have a great belief in your project.
Get up. dust yourself down and walk proud... Einstein was ridiculed as was copernercus and why? Because they dared walk outside the constraints of conventional wisdom.. well no new fronteirs are ever discovered by staying close to land. You must beleive ,as you do I am sure, in yourself. Dont worry about the critics.. if you posed no threat to them they wouldnt bother now would they
Keep up the good work
As soon as your kit is ready i will build one.. this is all over my head but I recognise genius when I see it.
Now put your mouthguard back in and get back in the ring..
Regards
Nick Mega
Australia
Einstein did not overturn conventional wisdom... he extended it. Einstein wasn't truely ridiculed until he choose to work by himself, ignoring the works of others.
Copernicus was not up against conventional wisdom... he was up against organized religion. Consider things here for example.
Linear interpolation reinforces the very image freq's that any form of oversampling is intended to remove. Do the math.
Copernicus was not up against conventional wisdom... he was up against organized religion. Consider things here for example.
Linear interpolation reinforces the very image freq's that any form of oversampling is intended to remove. Do the math.
John,
This my first post on this thread.
I have more than 50 years of experience in audio.
I think I saw almost everything from tubes, mono high fidelity, LPs, ICs, microprocessors, compact disk, digital audio including video.
Along these years, I had the privilege to exchange ideas or to follow the works of great designers such as Samuel B. Marantz, Joseph Curcio, Erno Borbely, Walt Jung to name only those.
I am also very much in admiration for the contributions of Nelson Pass, Radford, etc. I will stop there because the list would be endless and I would surely forget too many of these valuable contributors.
I think you belong with these inovators.
Digital audio will never be the same after you, sir. You will be copied, imitated, criticised, so what!
In the 50's the great pioneers had their critics also and you know what? They are all buried. Nothing is left from them, not even their saliva.
In 3 weeks from now, I will be celebrating one of my old friend's birthday. He is much older than me, he could be my father, imagine!
He will turn 99.
I will tell you his secret, he never quited.
The soldering iron is on the table next to his bed ready to fire on any project that catches his interest.
Being an amateur radio operator every day you can hear him on 2M and when propagation permits he is DXing in Morse code on the 20 M band.
The day he will stop is because he has closed his eyes for eternity.
He is an inspiration for me, I hope he becomes one for you too.
John, walk your way and let others follow, if they can!
Jean-Charles
This my first post on this thread.
I have more than 50 years of experience in audio.
I think I saw almost everything from tubes, mono high fidelity, LPs, ICs, microprocessors, compact disk, digital audio including video.
Along these years, I had the privilege to exchange ideas or to follow the works of great designers such as Samuel B. Marantz, Joseph Curcio, Erno Borbely, Walt Jung to name only those.
I am also very much in admiration for the contributions of Nelson Pass, Radford, etc. I will stop there because the list would be endless and I would surely forget too many of these valuable contributors.
I think you belong with these inovators.
Digital audio will never be the same after you, sir. You will be copied, imitated, criticised, so what!
In the 50's the great pioneers had their critics also and you know what? They are all buried. Nothing is left from them, not even their saliva.
In 3 weeks from now, I will be celebrating one of my old friend's birthday. He is much older than me, he could be my father, imagine!
He will turn 99.
I will tell you his secret, he never quited.
The soldering iron is on the table next to his bed ready to fire on any project that catches his interest.
Being an amateur radio operator every day you can hear him on 2M and when propagation permits he is DXing in Morse code on the 20 M band.
The day he will stop is because he has closed his eyes for eternity.
He is an inspiration for me, I hope he becomes one for you too.
John, walk your way and let others follow, if they can!
Jean-Charles
Well Poobah, what do you advise then. IIR?
http://kondor.etf.bg.ac.yu/~lutovac/zip/Lecture13.ppt
Btw, Wadia used in the 90's digital filters with their own designed bio-algorithm. Designed with repect to biological hearing process (at that time)
http://kondor.etf.bg.ac.yu/~lutovac/zip/Lecture13.ppt
Btw, Wadia used in the 90's digital filters with their own designed bio-algorithm. Designed with repect to biological hearing process (at that time)
dual format timing chain schematics
Hi tubee,
Thanks for your encouraging words [post#860]
Yes, combining all these activities is very hard work, I actually did listen to the octal D-I DAC all day, testing the USB to I2S interface. I am very gratefull for the support I get from diyAudio members.
So let's get on with the project. I have been optimizing the USB to I2S interface lately, especially the reclock circuit. Asynchronous reclocking usually takes 2 clock cycles of the reclock source (48 MHz with the USB interface). One to lock the positive going edge, one to lock the negative going edge (2 D flipflops in cascade). I only used one D flipflop for the positive going edge of BCK and a digital (crystal controlled) one shot circuit to overrule / lock the negative going edge. So the circuit acts like being reclocked at 96 MHz, the time between the rising and falling edge of the reclocked BCK is now fixed. Next I am planning to go even further by locking on both positive and negative going edge of the reclock signal, whichever comes first locks the positive going edge of BCK. This would compare to a reclock frequency of 192 MHz.
I also added a schematic diagram of the autodetecting dual format timing chain, since I haven't posted it yet.
This circuit accepts both philips and sony format signals. So the I2S interface that is now standard for the octal D-I DAC can be used for both.
Shift registers U1...U7 generate the necessary DATA delays for both formats D6...D56. U8 is used as synchronous divide by 6 or 8 register during the positive half of WS, U9 is used as synchronous divide by 6 or 8 register during the negative half of WS. This is necessary in order to maintain perfect synchronization with both BCK and WS. Taps are provided for philips and sony format WS delays. Both U8 and U9 provide the synchronized clock signal for the actual WS shift register U10. So basically the WS delay circuit only needs 3 shiftregisters. The different tap settings for each format are necessary to maintain equal delays between interpolated samples.
U11 is the format converter, it delays WS 7 BCK pulses and inverts it in order to accept the sony format. The format converter is bypassed when the philips format is detected.
U12 and U13 are used for actual format detection. Detection is obtained by strobing unique patterns derived from counter U12. The blue LED lights when philips format is detected, The white LED lights when sony format is detected.
U14...16 are multiplexers (digital switches) that select all necessary signals according to the received format.
U19...U22 are inverters used to obtain ND2, ND4, ND6 and ND8.
Hi tubee,
Thanks for your encouraging words [post#860]
Yes, combining all these activities is very hard work, I actually did listen to the octal D-I DAC all day, testing the USB to I2S interface. I am very gratefull for the support I get from diyAudio members.
So let's get on with the project. I have been optimizing the USB to I2S interface lately, especially the reclock circuit. Asynchronous reclocking usually takes 2 clock cycles of the reclock source (48 MHz with the USB interface). One to lock the positive going edge, one to lock the negative going edge (2 D flipflops in cascade). I only used one D flipflop for the positive going edge of BCK and a digital (crystal controlled) one shot circuit to overrule / lock the negative going edge. So the circuit acts like being reclocked at 96 MHz, the time between the rising and falling edge of the reclocked BCK is now fixed. Next I am planning to go even further by locking on both positive and negative going edge of the reclock signal, whichever comes first locks the positive going edge of BCK. This would compare to a reclock frequency of 192 MHz.
I also added a schematic diagram of the autodetecting dual format timing chain, since I haven't posted it yet.
This circuit accepts both philips and sony format signals. So the I2S interface that is now standard for the octal D-I DAC can be used for both.
Shift registers U1...U7 generate the necessary DATA delays for both formats D6...D56. U8 is used as synchronous divide by 6 or 8 register during the positive half of WS, U9 is used as synchronous divide by 6 or 8 register during the negative half of WS. This is necessary in order to maintain perfect synchronization with both BCK and WS. Taps are provided for philips and sony format WS delays. Both U8 and U9 provide the synchronized clock signal for the actual WS shift register U10. So basically the WS delay circuit only needs 3 shiftregisters. The different tap settings for each format are necessary to maintain equal delays between interpolated samples.
U11 is the format converter, it delays WS 7 BCK pulses and inverts it in order to accept the sony format. The format converter is bypassed when the philips format is detected.
U12 and U13 are used for actual format detection. Detection is obtained by strobing unique patterns derived from counter U12. The blue LED lights when philips format is detected, The white LED lights when sony format is detected.
U14...16 are multiplexers (digital switches) that select all necessary signals according to the received format.
U19...U22 are inverters used to obtain ND2, ND4, ND6 and ND8.
Attachments
Hi EC, thanks for continuing your project. I for one support you a 100% and admire you for remaining calm and professional in face of people who just don't get it. They can reference sampling theories and untested schematics, but the proof is in the sound, not theories. You have done this admirably.
My old college physics professor, discoverer of the neutrino and Nobel laureate, reminded graduate students who take theories as doctrines that theories are only as a good as their assumptions. Sage advice.
My old college physics professor, discoverer of the neutrino and Nobel laureate, reminded graduate students who take theories as doctrines that theories are only as a good as their assumptions. Sage advice.
Oh dear EC, you've achieved cult status now. You're going to have followers whether you like it or not.
As far as the criticism goes it does seem fairly tame compared the vitriol heaped upon gmarsh for having the audacity to design a dac that does not a TDA154x and you do hold some unconventional views on the way the DIDAC works. All things considered, they are only words and as you plan to carry down this path why worry about it.
As far as the criticism goes it does seem fairly tame compared the vitriol heaped upon gmarsh for having the audacity to design a dac that does not a TDA154x and you do hold some unconventional views on the way the DIDAC works. All things considered, they are only words and as you plan to carry down this path why worry about it.
Francsmith wrote:
Heard the D-I DAC you meant?
In that case notre cher Jean-Charles forgot to mention that he built it?
Please confirm.
Dear Ecdesigns,
So far I admire your vision, effort and endurance...but don't even think that I'm a blind follower. If you make a mistake I'll be there to put you in evidence! 
Regards
M
Heard the D-I DAC you meant?
In that case notre cher Jean-Charles forgot to mention that he built it?
Please confirm.
Dear Ecdesigns,
So far I admire your vision, effort and endurance...but don't even think that I'm a blind follower. If you make a mistake I'll be there to put you in evidence!
Regards
M
There is a difference between attacking an opposing idea and attacking the person who holds said idea.
Apparently, some people, for all their advanced knowledge, have forgotten the more basic, intrinsic things in life.
Like manners for example.
This site is about DIY - Do It Yourself. Not DESIGN It Yourself. The impression I distinctly receive here towards my (and others) lack of knowledge is one of hostility. Some more learned members here seem to enjoy ridiculing and insulting their less learned peers.
I do not claim to know digital design in depth (I have more experience with building [not designing] tubed equipment). My chosen specialty in life is medicine, not electrical engineering. I would not patronise you if you didn't know the difference between Wernicke's or Broca's area - I would think to myself instead, how would you know it anyway? You would have no experience with medical jargon, nor the raw knowledge that I do. But I would not hold it against you.
If you have knowledge, why not share it? And share it in a useful format - ie one that takes the jargon out and explains concepts instead of making them seem more convulated. Or at least direct less learned members here to where these resources may be accessed.
I see very little of that in this particular forum. It seems that one has to be an EE, or have an education pertaining to circuit design to be able to join a little 'club' of gurus who can make no mistakes.
There seems to be some confusion over the positive feedback exhibited in this thread - people confuse praising the efforts of a designer as opposed to praising his actual design.
I have not heard the Octal DAC. I do not know for a fact that it sounds good. What I do know however, is that EC has put a lot of effort into it, and even more effort into documenting his progress here. And he takes suggestions too. And replies to those who disparage his design. And replies politely.
And it is from this that I derive the confidence to praise him: good work EC, keep it up!
Apparently, some people, for all their advanced knowledge, have forgotten the more basic, intrinsic things in life.
Like manners for example.
This site is about DIY - Do It Yourself. Not DESIGN It Yourself. The impression I distinctly receive here towards my (and others) lack of knowledge is one of hostility. Some more learned members here seem to enjoy ridiculing and insulting their less learned peers.
I do not claim to know digital design in depth (I have more experience with building [not designing] tubed equipment). My chosen specialty in life is medicine, not electrical engineering. I would not patronise you if you didn't know the difference between Wernicke's or Broca's area - I would think to myself instead, how would you know it anyway? You would have no experience with medical jargon, nor the raw knowledge that I do. But I would not hold it against you.
If you have knowledge, why not share it? And share it in a useful format - ie one that takes the jargon out and explains concepts instead of making them seem more convulated. Or at least direct less learned members here to where these resources may be accessed.
I see very little of that in this particular forum. It seems that one has to be an EE, or have an education pertaining to circuit design to be able to join a little 'club' of gurus who can make no mistakes.
There seems to be some confusion over the positive feedback exhibited in this thread - people confuse praising the efforts of a designer as opposed to praising his actual design.
I have not heard the Octal DAC. I do not know for a fact that it sounds good. What I do know however, is that EC has put a lot of effort into it, and even more effort into documenting his progress here. And he takes suggestions too. And replies to those who disparage his design. And replies politely.
And it is from this that I derive the confidence to praise him: good work EC, keep it up!
Hi, I'm a newby, sorry if the question is not ok technically. Is the using of DAC chips in parallel the same as what Accuphase did in 1992 with their reference DC-91 DAC?
http://s96.photobucket.com/albums/l...urrent=c34b3378.jpg&refPage=&imgAnch=imgAnch1
Chris
http://s96.photobucket.com/albums/l...urrent=c34b3378.jpg&refPage=&imgAnch=imgAnch1
Chris