If the ESS DAC truly eliminates jitter then I guess it shouldn't matter if the isolation adds a little.
BTW don't the U.FL jacks have a 50 ohm impedance? Is that the correct impedance for I2S lines?
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I was kind of hoping it wouldn't have S/PDIF. May save a little cost. Someone's gotta start getting rid of S/PDIF.
No, there is not correct impedance for I2S lines, as they were never meant to leave the circuit board. I2S (really IIS, or Inter-IC Sound) was designed for interfacing two nearby chips. If you add a line driver for distance, the correct impedance will depend on the design of the transmitter and receiver.
S/PDIF was designed to transmit digital audio over cables.
http://www.nxp.com/acrobat_download2/various/I2SBUS.pdf
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Nonsense
DACs with I2S input (of the top of my head, there are more):
Northstar
Stello
Empirical Audio
PS Audio
Perpetual Technologies
Zanden
I guess all these manufacturers did not get the memo that "DACs aren't supposed to have I2S inputs"!
Yes, SPDIF was designed to have a convenient interface on a single wire for consumer use, it is an interface which does not offer the highest performance possible, as the embedding and stripping out of the clock signals causes additional jitter problems. Too bad that some folks are still chained to SPDIF in their mind. Like any DAC chip, the ESS 9018 sounds much better with a lower jitter feed, contrary to claims, it is not "jitter immune".
Tonight I will be fitting a USB-I2S board (with filtered/regulated battery power supply) to my B-II for testing, should be fun!
DACs with I2S input (of the top of my head, there are more):
Northstar
Stello
Empirical Audio
PS Audio
Perpetual Technologies
Zanden
I guess all these manufacturers did not get the memo that "DACs aren't supposed to have I2S inputs"!
Yes, SPDIF was designed to have a convenient interface on a single wire for consumer use, it is an interface which does not offer the highest performance possible, as the embedding and stripping out of the clock signals causes additional jitter problems. Too bad that some folks are still chained to SPDIF in their mind. Like any DAC chip, the ESS 9018 sounds much better with a lower jitter feed, contrary to claims, it is not "jitter immune".
Tonight I will be fitting a USB-I2S board (with filtered/regulated battery power supply) to my B-II for testing, should be fun!
I didn't say DAC's are not supposed to have I2S inputs, I said I2S was not designed to transmit over distance, so there is no "correct impedance." All of those manufacturers (or at least the ones I have looked into) use either buffers or line drivers, often of their own spec, to do it, each with it's own proper configuration.
Nothing wrong with that.
Agreed...
Russ, I agree that the ESS 9018 uses a very interesting approach to SPDIF reception. I have read all the available (public domain) stuff, including some of the patent stuff, and have formed a general understanding of how the SPDIF receiver works. This does not change the fact the DAC sounds better when provided a low jitter SPDIF feed rather than a high jitter one. I have used a few different sources with my B-II, and it sounds different with all of them.
There are many approaches out there to reducing jitter, and many DACs claim they are "jitter immune", it is entirely possible that the ESS is more "jitter immune" than anything else, but nothing, in my experience, has ever really achieved "jitter immunity"-everything still sounds better when the source is truly low jitter to begin with.
I really do not want to harp on this too much, I just do not want potential TPA customers (and I am a very happy customer, and love what you guys are doing) to think that they should not be concerned about source jitter with the B-II,III, because my experience has shown that if one wants to truly find out how good these DACs are, one should try and supply as low jitter a source as possible.
Embedding and stripping out of clock hardly matter if the clock is ignored.
ES9018 does not decode SPDIF like any other device I know of, it is very unique in it approach.Dustin actually provides some gems on the way it works but you will have to search for them.
Russ, I agree that the ESS 9018 uses a very interesting approach to SPDIF reception. I have read all the available (public domain) stuff, including some of the patent stuff, and have formed a general understanding of how the SPDIF receiver works. This does not change the fact the DAC sounds better when provided a low jitter SPDIF feed rather than a high jitter one. I have used a few different sources with my B-II, and it sounds different with all of them.
There are many approaches out there to reducing jitter, and many DACs claim they are "jitter immune", it is entirely possible that the ESS is more "jitter immune" than anything else, but nothing, in my experience, has ever really achieved "jitter immunity"-everything still sounds better when the source is truly low jitter to begin with.
I really do not want to harp on this too much, I just do not want potential TPA customers (and I am a very happy customer, and love what you guys are doing) to think that they should not be concerned about source jitter with the B-II,III, because my experience has shown that if one wants to truly find out how good these DACs are, one should try and supply as low jitter a source as possible.
Sorry
For the misunderstanding Brian, my response, and quote, was to labjr, and not directed at your post.
For the misunderstanding Brian, my response, and quote, was to labjr, and not directed at your post.
Yeah Russ...
I figured. Clearly to me the ESS chip has a lot of very interesting stuff going on. The more I play with my B-II, and tweak power supplies and such, the more performance I get, it sounds so good, then when one thinks it could not get better, a little different configuration results in even better sound, amazing!
I just want the users out there to know that it is totally worth paying attention to all the details as you can, because every time you make an improvement, the B-II/III rewards you with better sound.
I am really looking forward to the USB interface, I am sure you will produce a fantastic design. Thanks, as usual, for all you and Brian do.
I figured. Clearly to me the ESS chip has a lot of very interesting stuff going on. The more I play with my B-II, and tweak power supplies and such, the more performance I get, it sounds so good, then when one thinks it could not get better, a little different configuration results in even better sound, amazing!
I just want the users out there to know that it is totally worth paying attention to all the details as you can, because every time you make an improvement, the B-II/III rewards you with better sound.
I am really looking forward to the USB interface, I am sure you will produce a fantastic design. Thanks, as usual, for all you and Brian do.
What I gathered from Brian and other things I've read it seems to me that I2S wasn't designed to be used outside the box. Apparently, the companies which do are turning it into a their own proprietary interface so they can make a 2 chassis DAC system. But not to have a I2S universal input so to speak. Maybe companies like Empirical can put a higher price tag on it this way.
BTW, Maybe you don't need to be in these forums. There's nothing more you can learn because you seem to know everything.
labjr...
Sorry, I did not mean to offend you, I just wanted to point out that it is not all that uncommon for companies to use I2S interfaces. As to knowing everything, hardly! I am here to learn as much as anyone, and as I have learned a lot here, if I can contribute back something on occasion I will try and do so.
I have a huge interest in TPAs forthcoming USB product, and if I come across ideas that might help in any way, I will bring them up-of course, in most cases, Russ has already thought of everything, as he tends to sweat the details.
I do want Buffalo users to sweat the details as well, because this DAC is so good, it keeps on giving as one refines their implementation. I overreacted a bit because I know form experience with this DAC that it is worth going to extremes in getting it a low jitter feed in order to get the best out of it.
As to I2S, people use this format because it circumvents the compromises inherent in SPDIF, no matter how small those compromises might be-SPDIF was developed to be a convenient consumer interface, and not for ultimate performance.
Sorry, I did not mean to offend you, I just wanted to point out that it is not all that uncommon for companies to use I2S interfaces. As to knowing everything, hardly! I am here to learn as much as anyone, and as I have learned a lot here, if I can contribute back something on occasion I will try and do so.
I have a huge interest in TPAs forthcoming USB product, and if I come across ideas that might help in any way, I will bring them up-of course, in most cases, Russ has already thought of everything, as he tends to sweat the details.
I do want Buffalo users to sweat the details as well, because this DAC is so good, it keeps on giving as one refines their implementation. I overreacted a bit because I know form experience with this DAC that it is worth going to extremes in getting it a low jitter feed in order to get the best out of it.
As to I2S, people use this format because it circumvents the compromises inherent in SPDIF, no matter how small those compromises might be-SPDIF was developed to be a convenient consumer interface, and not for ultimate performance.
Not on this thread.
Definitely off topic.As for I2S. I have a nice solution for that.
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