Hi Ian,
Thanks, good news. So without external MCLK, I need a USB Xmos with an mclk output. But an external MCLK would work too if I feed with it the USB Xmos then the PCM and the DAC if I don't use the bclk output of the PCM to the DAC board... (the last seems illogical, but I'm asking in the case of a home mclk board stacked just above the dac for short connections without Fifo to rule all the device with its Crystal... I understand this Crystal must be 45.x or 49.x because the Xmos : yoour answer !)
I have maybe miss something because my English: I'm on the list for a PCM boards for 2 months (and I'm moving today for 2 boards) without FIFO: do I have to paypall you or wait an invoice payment from you. I don't understand if this is due because you are very busy or if I did a mistake in the procedure... sorry to take your time with 2 cents logistic questions
Thanks, good news. So without external MCLK, I need a USB Xmos with an mclk output. But an external MCLK would work too if I feed with it the USB Xmos then the PCM and the DAC if I don't use the bclk output of the PCM to the DAC board... (the last seems illogical, but I'm asking in the case of a home mclk board stacked just above the dac for short connections without Fifo to rule all the device with its Crystal... I understand this Crystal must be 45.x or 49.x because the Xmos : yoour answer !)
I have maybe miss something because my English: I'm on the list for a PCM boards for 2 months (and I'm moving today for 2 boards) without FIFO: do I have to paypall you or wait an invoice payment from you. I don't understand if this is due because you are very busy or if I did a mistake in the procedure... sorry to take your time with 2 cents logistic questions
The process is normally alongh the lines of this:
1. interest list builds up
2. wait
3. when Ian has both time and sufficient interest he'll start building up stock of PCBs and parts and assemblies then open up the GB. This will come with a new form/spreadsheet.
4. Fill the form out with the final order (can vary from from expression of interest) and send to Ian.
5. Follow any other instructions that Ian provides when he announces GB.
We're currently in the 'wait' phase but Ian's earlier comment was that he might run a limited GB for the i2stoPCM board only as stock and interest (and his time) for the others are making it not worthwhile
Hopefully that's made the general process clearer? Let me know if there is anything that is unclear and I'll try again ... no stupid questions here, I'd rather spend a few minutes typing rather than have confusion rain and have you miss out on an opportunity
Not sure if it was understood from earlier posts, but just to be doubly sure, there is input u.fl on underside of the i2s to PCM board, but they're unpopulated so you need to solder them yourself.
Chris
Hi Drew,
Both PureMusic and Amarra can do bit-perfect playing at music's native Fs. I2S to PCM board is also running at pit-perfect mode doesn't do any up-sampling or re-sampling job. My configuration was iMac-PureMusic (or Amarra)-USB-FIFO-Clock board-PCMboard-TDA1541A( simultaneous mode ). With similar system, you can do anything which you prefer.
Both Si570 clock board and dual xo clock board (with 45/49MHz XOs) can drive the PCM board and DAC running up to 384KHz. Full/Half speed can not be adjust automatically with current design, it doesn't change the SQ according my listening test. But if your really want, you can try some external logic, I don't see there is any problem.
Regards,
Ian
I am pretty sure they are DIY. I did similar once, I got longer u.fl cables and cut in half and used each half. That way 2 longer cables made 4 shorter u.fl to wire terminated leads.
Chris
A question I've been meaning to ask of those who...
know much more about high-speed signal transmission and impedance-matching than I...
When interfacing I2S data and clock signals between a board with u.fl sockets on one end and a header on the other, is it better to use a cut u.fl cable as Chris describes below soldered to the header end (preferably after removing the header and going directly to the board) or is it better do a 'makeshift' u.fl socket adapter and use a stock (un-cut) u.fl cable?
Inquiring minds are waiting for your responses!
Greg in Mississippi
know much more about high-speed signal transmission and impedance-matching than I...
When interfacing I2S data and clock signals between a board with u.fl sockets on one end and a header on the other, is it better to use a cut u.fl cable as Chris describes below soldered to the header end (preferably after removing the header and going directly to the board) or is it better do a 'makeshift' u.fl socket adapter and use a stock (un-cut) u.fl cable?
Inquiring minds are waiting for your responses!
Greg in Mississippi
I'd vote for either/or really. Depends how cleanly the u.fl makeshift can be connected to the signal and ground pads. If it's pretty hard to attach the u.fl socket then probably no meaninful difference really. If you have a gnd plane on that side of the PCB and you're able to scrape solder mask away you may be able to get an improvement with u.fl. But be careful with the socket, the underside has an exposed part directly under the signal termination in the centre where the signal could short to whatever is underneath so try to keep that solder mask under that to ensure you don't short signal and gnd.
The return signal path has to be the closest to the signal wire : so flat wire with one gnd (G) wire for each signal (S) wire à la : GSGS etc . It could be also better to put a larger flat cable to put a wire with no signal (N) between a S and the G used for the other S : like that SGNSGNSG: the signal return go always to the closest path but with that flat cable arrengement with a space between each GS : there is maybe a better separation of the I2S signals : if I'm wrong specialists will correct me !
BUT... with UF.L wire and connectors : G&S are always very close to each others with a constant impedance matching & the coax arrengement provide a good insulation like the connector provide on the pcb to use few soldering... It is the the way now diyers should have to go with RF. And of course as already said with r=the shortest wires... BTW if someone have a link or ref for Mouser for ufl wires, I have some difficulty to find it in the french Mouser pages...
that's my simple understanding after al the reads on diyaudion....WIth RF, too much diy pcb device make the econmy with it or in the worst case wa can see good design but unluckily wasted by some bad terminal layout with : GSSSS
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Please put your name on the waiting list of the GB thread. I'm considering running a GB for PCM board earlier.
Regards,
Ian
As promised, the list of interest is started.
http://www.diyaudio.com/forums/digi...-jitter-crystal-oscillator-4.html#post4057057
Hi Ian. I asked you by email, but I think this will be interesting for someone else.
Is it possible to run TDA1543A/44/45A with your I2S-PCM board?
Instead of regular 1543 version, 43A/44/45A are not I2S, but (from datasheet):
Compatible with most of the Japanese input formats: time multiplexed, two's complement and TTL
These chips like 1543 have only 3 pins for use: DATA, BCK and WS. As you can see there is no separate Data L and Data R pins. How to connect in this case to your I2S-PCM board? Or it is impossible? Thanks!
Is it possible to run TDA1543A/44/45A with your I2S-PCM board?
Instead of regular 1543 version, 43A/44/45A are not I2S, but (from datasheet):
Compatible with most of the Japanese input formats: time multiplexed, two's complement and TTL
These chips like 1543 have only 3 pins for use: DATA, BCK and WS. As you can see there is no separate Data L and Data R pins. How to connect in this case to your I2S-PCM board? Or it is impossible? Thanks!
Hi Bisesik,
All of them don't support simultaneous mode or other "PCM" format. So, I don't think you can use the PCM board in this case. But FIFO is possible.
Though it's not I2S input, but I'm not sure if it is "SONY" format or other Japanese format. FIFO support all other three formats besides of I2S,
"
left justified,
16 bit right justified,
24 bit right justified FIFO input format"
Maybe you can give a try.
Please refer to document "I2S FIFO Firmware V3.80 Upgrading" for setup detailed.
Regards,
Ian