And, stephensank
until I started into USB audio, I had a mid-range CD player connected via Toslink to the HT pre... and some 4" mids and planar tweets and a HT sub, sonic heaven at that time 3-4 years ago. Toslink is not just SPDIF it's galvanic isolation. The wars go on, some say copper SPDIF sound better? I only use PC or more likely MAC and FLAC and USB so I tune in on the supposed best of breed USB xfer technologies but without a total solution of galvanic isolation...I cannot say whether 480 Mbps screamin USB to I2s translation technology makes as much sense as it would seem on the surface. Can we Isolate that? or isolate at I2s level? Yah, the DAC stuff is pouring out to try and respond to what I allude to. I think driver free is always gonna be a winner, and noise-free too...so yah you can buy say 5--6-7-8x 480Mbps USB audio DAC solutions but do they break one realm to fix another? Anything PCM270## cm102 seems OLD, TE7022 is "mature" and works great, what of the next wave is truly worth the change? Xmos? Via Vunlyu ENy VT173## Tenor TE8802? CM6631? all USB to I2s chips. I do not use CD players so have no use for SPDIF of any kind. My USB isolation solutions only work at 12Mbps "so far"
until I started into USB audio, I had a mid-range CD player connected via Toslink to the HT pre... and some 4" mids and planar tweets and a HT sub, sonic heaven at that time 3-4 years ago. Toslink is not just SPDIF it's galvanic isolation. The wars go on, some say copper SPDIF sound better? I only use PC or more likely MAC and FLAC and USB so I tune in on the supposed best of breed USB xfer technologies but without a total solution of galvanic isolation...I cannot say whether 480 Mbps screamin USB to I2s translation technology makes as much sense as it would seem on the surface. Can we Isolate that? or isolate at I2s level? Yah, the DAC stuff is pouring out to try and respond to what I allude to. I think driver free is always gonna be a winner, and noise-free too...so yah you can buy say 5--6-7-8x 480Mbps USB audio DAC solutions but do they break one realm to fix another? Anything PCM270## cm102 seems OLD, TE7022 is "mature" and works great, what of the next wave is truly worth the change? Xmos? Via Vunlyu ENy VT173## Tenor TE8802? CM6631? all USB to I2s chips. I do not use CD players so have no use for SPDIF of any kind. My USB isolation solutions only work at 12Mbps "so far"
haha the English is fine, but walls of text are hard to read, I lose patience almost straight away and I know many feel the same way. probably posting on your phone?
USB is perfectly fine, even good for audio if you keep that in mind though, forget the high speed USB isolation, just isolate the i2s before the reclocking stage...done. as far as the data transfer its excellent IMO; impedance controlled differential signalling with error correction.
posting from phone = no
NO, I am just that much a writing cripple. I care but when I forget the rules I keep spewing. I hate cell_phones and the impacts thereof but I DO a=have a smart phone Android. I generally am on a MAC laptop and maybe in Firefox
NO, I am just that much a writing cripple. I care but when I forget the rules I keep spewing. I hate cell_phones and the impacts thereof but I DO a=have a smart phone Android. I generally am on a MAC laptop and maybe in Firefox
I disagree. The potential for sonically damaging "mischief" is, IMO, in the conversion froma straight data file to a PCM audio datastream, e.g., file to spdif. At i2s, it's already too late, the damage is done. Data files don't care about timing errors, but datastreams in PCM or DSD audio land care a hell of a lot about timing. People that think "bits are bits" or "bit perfect is all that matters" just don't comprehend that difference between data files & audio datastreams.
you can disagree all you like...
If you can show me some sort of proof that a bit perfect buffered, isolated i2s reclocker (no PLL, just memory buffered) which re-installs timing/jitter to less than 0.5ps with high grade clocks and potato logic flip-flops/clock buffers after the isolation and after discarding the original clock, is somehow effected by what comes before it with an explanation of how that comes about, i'm all ears.
phantom dark timing perhaps?
it just seems that some people like yourself perhaps, really want to hang onto stuff to worry about, long after the original problems are solved
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I trust what my ears, and those of younger people around me, perceive in a/b testing, and I have been doing this with digital audio systems for getting near to 30 years. A lot of things that are verifiably audible have not yet been quantifiably explained, but that is simply due to our failure to invent ways to measure what variable is the cause. Meitner's Museatex BiDAT has a jitter spec of 2ps peak, via spdif, no less, so low that he had to invent a better jitter measurement system to spec it, and yet that dac was still quite audibly and undeniably affected by source jitter.
I've been an audio service/design professional for 35 years+, and I quite firmly believe that we have as yet invented ways to measure barely half of that which determines how well any device reproduces actual music. All we have really mastered is measurement of repetitive waveforms, which are many orders of magnitude less complex than real world sounds.
I've been an audio service/design professional for 35 years+, and I quite firmly believe that we have as yet invented ways to measure barely half of that which determines how well any device reproduces actual music. All we have really mastered is measurement of repetitive waveforms, which are many orders of magnitude less complex than real world sounds.
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sorry edit time ran out.
you'll excuse me for not trusting your ears and not even those younger ones around you, to define a 'problem' in the sub 1ps range.... especially since you apparently do not have any idea where to look for the problem, or even what the problem is.
the mechanism I describe (Ians i2s Fifo buffer and other mechanisms like it) has no connection to ground and power supply of the PC and reads from local memory and is clocked out with the best clocks I can afford (~0.5ps). the timing information, which is where any minor damage could occur that isnt picked up in bitperfect tests; is discarded before this and the data is clocked out of memory with isolated clocks and clock buffers with battery supply and impedance controlled, synchronous connections to the dac.
in effect the transport/source becomes one mechanism with the dac, while being completely isolated from the computer.
i'm as neurotic as the next guy with audio tinkering, but even I need some basis for investigation. I prefer not to invent new issues out of thin air to disrupt happy listening time.
you'll excuse me for not trusting your ears and not even those younger ones around you, to define a 'problem' in the sub 1ps range.... especially since you apparently do not have any idea where to look for the problem, or even what the problem is.
the mechanism I describe (Ians i2s Fifo buffer and other mechanisms like it) has no connection to ground and power supply of the PC and reads from local memory and is clocked out with the best clocks I can afford (~0.5ps). the timing information, which is where any minor damage could occur that isnt picked up in bitperfect tests; is discarded before this and the data is clocked out of memory with isolated clocks and clock buffers with battery supply and impedance controlled, synchronous connections to the dac.
in effect the transport/source becomes one mechanism with the dac, while being completely isolated from the computer.
i'm as neurotic as the next guy with audio tinkering, but even I need some basis for investigation. I prefer not to invent new issues out of thin air to disrupt happy listening time.
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how well any device reproduces actual music
I spotted this on some other thread and found it interesting:
RMAF 11: Noise Shaping Sigma Delta Based Dacs, Martin Mallison, CTO, ESS Technology - YouTube
I spotted this on some other thread and found it interesting:
RMAF 11: Noise Shaping Sigma Delta Based Dacs, Martin Mallison, CTO, ESS Technology - YouTube
...and the Jitter lecture
you may wish to note another talk by him on Jitter, and digital vs analog volume control...
RMAF 11: Digital Jitter and Volume Controls, Martin Mallison, CTO, ESS Technology - YouTube
I hope our friend with the probably fried USB receiver is getting back on his feet? In some ways he's way ahead of me on the DAC DIY journey -- I have numerous USB receivers but have not had the time to burn any up. I hope to standardize on RJ45 for external use but more likely will be wiring I2S with wire-wrap wire and a bit of solder. I DID save a 3m hunk of tiny TwinAx from a 10Gbps ethernet cable. I dunno how touchy I2s is, I have dreamed also of a 4PDT center-off toggle switch for I2s --> could switch which receiver and which DAC IC with a few? Eina Klina DAC playground.
Great link, thanks
you may wish to note another talk by him on Jitter, and digital vs analog volume control...
RMAF 11: Digital Jitter and Volume Controls, Martin Mallison, CTO, ESS Technology - YouTube
I hope our friend with the probably fried USB receiver is getting back on his feet? In some ways he's way ahead of me on the DAC DIY journey -- I have numerous USB receivers but have not had the time to burn any up. I hope to standardize on RJ45 for external use but more likely will be wiring I2S with wire-wrap wire and a bit of solder. I DID save a 3m hunk of tiny TwinAx from a 10Gbps ethernet cable. I dunno how touchy I2s is, I have dreamed also of a 4PDT center-off toggle switch for I2s --> could switch which receiver and which DAC IC with a few? Eina Klina DAC playground.
you are assuming faaaaar too much ruggedness in i2s signalling, external use, or switching with a mechanical switch will dominate any error/jitter performance, the act of trying to compare them with such means will render them all sub-par. its designed for travelling mm->cm on PCBs thats all.
there is so much talk about i2s being superior, for internal use, or conversion from USB->i2s etc thats true, but you will add significant issues if you try to carry it too far, use a standard designed for such things, i2s as a standard doesnt even contain ground, because its not meant to leave the PCB.
yeah those talks from ESS at RMAF are pretty good
what is the missing link
we have
timing
data
if both are tested to be perfect, where is this missing element? anything else wasnt there to begin with. with i2s the data can be separated from the timing and new timing installed after isolation from any PC issues.
I really am interested, not being facetious, but until there is something to look for the claims are just noise
there is so much talk about i2s being superior, for internal use, or conversion from USB->i2s etc thats true, but you will add significant issues if you try to carry it too far, use a standard designed for such things, i2s as a standard doesnt even contain ground, because its not meant to leave the PCB.
yeah those talks from ESS at RMAF are pretty good
what is the missing link
we have
timing
data
if both are tested to be perfect, where is this missing element? anything else wasnt there to begin with. with i2s the data can be separated from the timing and new timing installed after isolation from any PC issues.
I really am interested, not being facetious, but until there is something to look for the claims are just noise
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I2s too far
...some eBay sellers have USB receiver products in chassis with RJ45 I2s export, also AUdioGD sold me TE8802 boards with options for RJ45 [5-pin flat IDC ribbon to RJ45], I bought maybe 10 RJ45 boards from them. NOT meaning to disagree with you at all. I have also got the technology to put DACs on larger DIP fanout PCBs that can take header pins, etc, std spacing. It would be fun to find out what "I like". Some of the Arduino prototypingboards looked handy, I have some of those too. I will take your advice and use the KISS method: "keep it short Silly" And, I have a CM6631 board to try too...I will run USB to the guts of whatever vs long I2S, THANKS!
...some eBay sellers have USB receiver products in chassis with RJ45 I2s export, also AUdioGD sold me TE8802 boards with options for RJ45 [5-pin flat IDC ribbon to RJ45], I bought maybe 10 RJ45 boards from them. NOT meaning to disagree with you at all. I have also got the technology to put DACs on larger DIP fanout PCBs that can take header pins, etc, std spacing. It would be fun to find out what "I like". Some of the Arduino prototypingboards looked handy, I have some of those too. I will take your advice and use the KISS method: "keep it short Silly" And, I have a CM6631 board to try too...I will run USB to the guts of whatever vs long I2S, THANKS!
yes, some ebay sellers are catering for audiophile fashion to sell units as well I trust ebay sellers to get it right least; its the most vulnerable of all. spdif is higher jitter as an interface because it has the jitter from the conversion from spdif->i2s, but to better it assumes perfect transmission/switching of i2s, which is not so easy, because using less than ideal connections, not impedance controlled connections etc. even the headers and ribbon you mention are far from the correct impedance for i2s and short isnt going to guarantee good; then add a switch and its all over
I trust ebay sellers to get it right least; its the most vulnerable of all. spdif is higher jitter as an interface because it has the jitter from the conversion from spdif->i2s, but to better it assumes perfect transmission/switching of i2s, which is not so easy, because using less than ideal connections, not impedance controlled connections etc. even the headers and ribbon you mention are far from the correct impedance for i2s and short isnt going to guarantee good; then add a switch and its all overEagle
I have the hobby license to Eagle CAD but am FAR too new at it, and to keep costs lower I'd want to DIY some small runs of boards...and probably want a hot-air station and suction grabber tool... I DID find a place in the States that makes VERY NICE PCBs EFABPCB I think it was, I had 50x 2-layer really extra thick and thick copper [paid options], I think it was $250-300/50. Problem is it's rough to get stuff like Tenor ICs, much less DIY solder them [though I watched a Youtube of some Asian woman doing it with just a pencil iron and then tapping the board on it's side against the table while that side of the square IC was all hot, I laughed]. SO for this DIY guy...I'll probably get USB receivers as modules. I think it's Twisted Pear that offers U_fl connectors for I2S signals? I can see myself swearing at sub-mini feedlines, junking old laptops for them
With what is left of my holidays I may try the CM6631, it wont be pretty, well, steal a 5pin ribbon assy from AUdio GD TE8802 project, or tack solder Kynar. I could just about hot-glue a ES9023 upside down on the $29 CM6631 board and try my hand at "dead bug" style DAC wiring, turn the house upside down finding the reels of SMD this and that. Or jump I2s to DIP fan-out.
There ARE many open projects on the net and probably here on DIYAUdio, with people like you who know how wide a trace needs to be and how far from ground-plane etc. I have not met just the right people to shoot holes in my ideas and also help make the Eagle CAD stuff come out perfect.
yes, some ebay sellers are catering for audiophile fashion to sell units as well
I have the hobby license to Eagle CAD but am FAR too new at it, and to keep costs lower I'd want to DIY some small runs of boards...and probably want a hot-air station and suction grabber tool... I DID find a place in the States that makes VERY NICE PCBs EFABPCB I think it was, I had 50x 2-layer really extra thick and thick copper [paid options], I think it was $250-300/50. Problem is it's rough to get stuff like Tenor ICs, much less DIY solder them [though I watched a Youtube of some Asian woman doing it with just a pencil iron and then tapping the board on it's side against the table while that side of the square IC was all hot, I laughed]. SO for this DIY guy...I'll probably get USB receivers as modules. I think it's Twisted Pear that offers U_fl connectors for I2S signals? I can see myself swearing at sub-mini feedlines, junking old laptops for them
With what is left of my holidays I may try the CM6631, it wont be pretty, well, steal a 5pin ribbon assy from AUdio GD TE8802 project, or tack solder Kynar. I could just about hot-glue a ES9023 upside down on the $29 CM6631 board and try my hand at "dead bug" style DAC wiring, turn the house upside down finding the reels of SMD this and that. Or jump I2s to DIP fan-out.
There ARE many open projects on the net and probably here on DIYAUdio, with people like you who know how wide a trace needs to be and how far from ground-plane etc. I have not met just the right people to shoot holes in my ideas and also help make the Eagle CAD stuff come out perfect.
Broken link
Broken link was to an emoticon a smile with big teeth at DIYAUDIO here, I don't know what happened.
But since you would enjoy a link, here is one showing the U.FL connectors being used for I2S
The Buffalo-IIISE (Stereo Edition) 2-Channel DAC
Speaking of things ESS, my TE7022//ES9023 ODAC want-to-be from HifiMEDIY showed up today [wrong QTY in the package arrgh, working on them about THAT]. I am having to use the WIndows Mixer and Jriver's volume etc at about 1/2, I think due to ~1.9V P-P rolling out of ES9023. Their next cool updated model will have a POT at output and USB isolation for better or worse. *I* am using this with fiber optic isolation. So, I'm pretty happy but WILL void the WTY ASAP. maybe a POT with also fixed R protection [from hitting ground], I have also some Foxcon? 3.3V SMD TCXO at 12.000MHz, I might drop one in and try to not to let any smoke out. If it is using one 3.3V regulator I will drop in one just for the DAC [3.3 or 3.6 ES9023 can take]. So the DAC assy may get a new box too. I found
Hammond 1593KBK $2.74USD Ea. but $10 Min. orders...guess I need 5
Hammond 1593KBK Handheld Plastic Enclosure 2.6 X 2.6 X 1.1, Black
I DO hope we hear from our friend who had the batteries mishap. I had a Behringer UCA-202 hooked up 4hr today and that was ppainful. [PCM27## as I recall]
Broken link was to an emoticon a smile with big teeth at DIYAUDIO here, I don't know what happened.
But since you would enjoy a link, here is one showing the U.FL connectors being used for I2S
The Buffalo-IIISE (Stereo Edition) 2-Channel DAC
Speaking of things ESS, my TE7022//ES9023 ODAC want-to-be from HifiMEDIY showed up today [wrong QTY in the package arrgh, working on them about THAT]. I am having to use the WIndows Mixer and Jriver's volume etc at about 1/2, I think due to ~1.9V P-P rolling out of ES9023. Their next cool updated model will have a POT at output and USB isolation for better or worse. *I* am using this with fiber optic isolation. So, I'm pretty happy but WILL void the WTY ASAP. maybe a POT with also fixed R protection [from hitting ground], I have also some Foxcon? 3.3V SMD TCXO at 12.000MHz, I might drop one in and try to not to let any smoke out. If it is using one 3.3V regulator I will drop in one just for the DAC [3.3 or 3.6 ES9023 can take]. So the DAC assy may get a new box too. I found
Hammond 1593KBK $2.74USD Ea. but $10 Min. orders...guess I need 5
Hammond 1593KBK Handheld Plastic Enclosure 2.6 X 2.6 X 1.1, Black
I DO hope we hear from our friend who had the batteries mishap. I had a Behringer UCA-202 hooked up 4hr today and that was ppainful. [PCM27## as I recall]
hehe Twisted Pear are one of the last of the suppliers here to offer u.fl connectors after theyve become a bit of a defacto standard here... (as you can see from the soldering =) ) Acko, Ian and Lucian (and myself) have been using them for quite some time (years), they are very good. looks like TP have pretty unfriendly PCB patterns for them, designed for reflow soldering that will cause trouble for DIYers not used to them (including themselves); hopefully they fix that in a board revision. they are good but still you want to keep them as short as possible. keep the connect/disconnect cycles to a minimum
9023 is just soic package, dead easy to solder, much harder to deadbug than just solder properly. it takes 2 swipes and a quick cleanup, look for videos on drag soldering, its much easier than you think. but rather than doing your own PCB for USB, Lucians XMOS WaveIO board seems very good, as is the support. it uses u.fl.
9023 is just soic package, dead easy to solder, much harder to deadbug than just solder properly. it takes 2 swipes and a quick cleanup, look for videos on drag soldering, its much easier than you think. but rather than doing your own PCB for USB, Lucians XMOS WaveIO board seems very good, as is the support. it uses u.fl.
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