XMOS-based Asynchronous USB to I2S interface

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#624
I'm curious to know about users experiences with different DAC kits. I would like to purchase a WaveIO board.

I don't mind building from a kit, however I do not have the necessary expertise to design or fabricate PCB. I would also prefer not to bread board the unit.

I saw this site: Analog Metric - DIY Audio Kit which seems to sell many DAC kits.

I would appreciate any recommendations!

If you have experience with pre-built DACs that take I2S that would be interesting also. I would eventually like for these units to be inside enclosures.

I personally own a Schiit Bifrost and an Ibasso D7. I feel like this could be an interesting project and I require another DAC for my dedicated stereo.
 
#626
Opus 8740

A question for Wolfsin or whoever is successfully using WaveIO with a TP Opus 8740 module.
I don't get any output from the dac (but the module works fine with Teralink X2 I2S output) and WaveIO output clocks signals seems ok (non-isolated).
Which hardware setting are you using on Opus8740 with WaveIO?
Mine is a typical stereo (I2S high, dsd low, deemph low, mode low, iwo high, diffhw low, fsel off, mute off, osr off)
Thanks.
 
#627
I don't think Wolfsin has actually connected to the 8740 modules yet.

I am hoping to try it out with 8741 within the next week or so, exact timing depends how the power supply testing goes tomorrow. No smoke could mean I'll have feedback in a few days.

I think pinocchio was doing something with WaveIO and Opus boards ... haven't heard about any results yet though.
 
#628
Opus 8740 again

Well, reading 8740 and 8741 datasheets I noted this peculiar difference:

8740
The WM8740 supports data input word lenghts from 16 to 24 bits and sampling rates up to 192 kHz

8741
The WM8741 supports PCM data input word lenghts from 16 to 32 bits and sampling rates up to 192 kHz

If I'm not wrong, I remember that Lucian told that WaveIO I2S output is 32bits.

Could it be that difference the problem with 8740?
 
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#629
If I'm not wrong, I remember that Lucian told that WaveIO I2S output is 32bits.
Click to expand...
Yes, but from that 32 bits only 24 are used. I2S Data is left aligned (except the first bit after the Left/Right transition) while the rest of them are zero padded. You can see descriptions of I2S interface here, at page 13 (bottom) and here, at page 23, below the I2S Mode paragraph.
At first sight you ave to make sure that your DAC chip has Audio Input format configured to 24-bit I2S data (pin 28 & pin 23 = High).
Kind regards,
L
 
#630
Opus 8740 + WaveIO now works

Problem seems solved.
I used I2S cables lenght of 170mm at the beginning in order to have the chance to be able to move the board in case of need.
I've cut the cable to 70mm and now I got analogue output on the scope.
With X2 I used a I2S cat5 cable of about 150mm with no problem, so I started with a similar length, but it's clearly not sustainable in this new setup.
Thank to Lucian for the time dedicated and help by mail.
 
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#632
external usb (with a usb cable I'm crafting) and external power are two future steps in search of improvement.
At that point I'll turn WaveIO 90° counterclockwise and I2S cable will be less than 10mm.
Just a hint for whoever need a connector for isolated pins at nearly no cost: an old ide connector
 

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#633
m.massimo said:
A question for Wolfsin or whoever
Click to expand...

Thanks hochopeper for answering correctly. I am exploring digital sides of WaveIO and WM8740 but have yet to connect. There is no DPC latency issue on any of my computers except the eeePC portable. I am writing a small Windows dialog app to control the Diolan->WM874x register interface. It will also respond to http gets with a tiny webpage for the Palm Tungsten so I will have volume, balance, and mute thru wi-fi. Tungsten C was shipped with a web browser and wi-fi and I just received one for US$6.14 shipped 😀
 
#636
quick answer is: No. No such device exists to my knowledge.

You may be able to have a low powered computer local to the WaveIO device and connect to storage somewhere else on the network though that adds a layer of complexity I think you're trying to avoid ...
 
#637
m.massimo said:
external usb (with a usb cable I'm crafting) and external power are two future steps in search of improvement.
At that point I'll turn WaveIO 90° counterclockwise and I2S cable will be less than 10mm.
Just a hint for whoever need a connector for isolated pins at nearly no cost: an old ide connector
Click to expand...

you know that screw terminal will be decimating any impedance matching you achieve with those u.fl cables right? its completely possible to turn that input into a bank of 4 x u.fl
 
#638
gabanyayaya said:
Hi Lorean

A quick question. Is it possible to connect between a pc and the usb to i2s interface via wifi or wireless bridge by using some kinda of usb to wireless adapter ?
Click to expand...

There's a project somewhere that allows usb over ethernet, I think the host has to be linux but I could be wrong. An old thin client or something like a beagle board would be more than sufficient. But you could also turn that old thin client into a squeezebox/mpd-server/etc.

-- Sent from my Palm Veer using Forums
 
#640
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