XMOS-based Asynchronous USB to I2S interface

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RSDIO, Barrows:
This does pretty much what Barrows described http://www.diyaudio.com/forums/digi...ifo-project-ultimate-weapon-fight-jitter.html

There are tricks for resyncronizing so the sync issue won't bite, as long as the source isn't too far off tolerance. One trick is to watch for digital silence and reset there. Another is to reset the clock frequency at digital silence to match the approx incoming sample rate. If the clocks match pretty closely (not a difficult proposition) they you could play for a very long time before its an issue. NuForce uses a technique like this in their new digital stuff.

I have inadvertently ran a pro audio DAC with an internal clock option set to internal clock (open loop) and got a glitch every 5-10 minutes. There was no synchronization at all and it worked pretty well with a $150 computer interface card driving it. Took a while to figure out what the problem was.

If the clocks meet the AES standard (5ppm) then you would have 200,000 frames (word clocks) before you got a glitch: about 5 minutes on the back of my envelope. If you used high precision (.5 ppm) clocks you may never get a glitch. The track would stop and restart before its an issue.
 
2nd attempt at integrating wave io

Hi
This is my second attempt at trying to use wave io.
Wave io works well with buffalo 2 and give an excellent sound. thanks to Lorien.
However, there is an intermittent drop out .
I am using window 7 in an atom based fanless pc and the player is itune. I have stopped the antivirus .
I am new to pc audio and hope someone will point me towards correct reading material to optimise window for audio.
attached is my set up

thanks

kp93300
 

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Hi
This is my second attempt at trying to use wave io.
Wave io works well with buffalo 2 and give an excellent sound. thanks to Lorien.
However, there is an intermittent drop out .
I am using window 7 in an atom based fanless pc and the player is itune. I have stopped the antivirus .
I am new to pc audio and hope someone will point me towards correct reading material to optimise window for audio.
attached is my set up

thanks

kp93300

Try J River using WASAPI Event Style output. You can try it for 30 days I believe. Never had any skips using this player and the combination of my other equipment.

I just wouldn't use iTune as a good player in Windows...

Do
 
I'm very interested in this thing. I'm waiting for a ADuM4160 isolator to be delivered and this incompatibility could be a problem, if confirmed. Is there anyone who have used ADuM4160+WaveIO successfully?

ADUM4160 only works in USB 1.0 or 1.1 mode, so i think there's no way it can work with WaveIO.
Anyway i've tried an ADUM4160 in the past (with a PCM2707, a USB 1.0 receiver) and only obtained a muffled sound, really unlistenable and sold it immediately.

Cheers.
 
. . . I've tried an ADUM4160 in the past (with a PCM2707, a USB 1.0 receiver) and only obtained a muffled sound, really unlistenable
Then I'm afraid you must have had it set up wrong for whatever reason. I drove a PCM2707 via a ADuM4160 for over two years with excellent results and know of many others who have had similar results, inc folk who use them at 96KHz/24-bit on Macs. Where it is appropriate, it works well.

That said, let's not get too hung up on the thing - straight out the box, the WaveIO is way, way ahead of any PCM270x implementation with or without USB isolation. In any case, the WaveIO provides isolation on the I2S bus which some designers say is the better place to have it.
 
The ADUM4160 is only for low speed and full speed USB. No 480 Mbps mode.
Thanks for the info but I think we're pretty well clear on that.
I grilled my ADI guy about a 480 Mbps and its not even on the roadmap for now. UAC2 really requires High Speed USB to work
What I'm not so clear about is what USB speeds the device uses at lower data rates - not everyone uses or wants to use 24/192. I haven't found an answer in Xmos literature or elsewhere but I'm not looking very hard either - see my last post. I'm very happy with the WaveIO as it is.
 
in window's world all motherboards have on board or external audio card, therefore a proprietary software is included with such a audio card, therefore that audio software, plus the WaveI/O driver software, makes for 1 software too many., if one wants to bypass the first audio card software then head for the PC's bios and turn it off. It's not required if one is using Wave I/O, the USB data will have one less algorithm to deal with. the end result will be same sound signature emanating from any window's platform and that includes linux.
Foobar is really apt to handle many many codex which are included in the player itself, it's simplicity yet sophisticated formats delivers. to keep it simple one can use Wav format to record incoming signal which will be and sound exactly as, what you hear is what you get, that includes from online streaming to recording cd's .
 
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What I'm not so clear about is what USB speeds the device uses at lower data rates - not everyone uses or wants to use 24/192. I haven't found an answer in Xmos literature or elsewhere but I'm not looking very hard either - see my last post. I'm very happy with the WaveIO as it is.

UAC1 and UAC2 are enough different that the device can't switch dynamically between them. In UAC2 it seems all the communications are at high speed even for a 44.1 file. It sort of makes sense because negotiating a high speed link is a little involved and you don't want to switch once engaged. UAC reserves some bandwidth for the audio stream (what they mean by isochronous) so the audio won't get hammered by a disk transfer on the same host. At lower data throughput it probably releases more bandwidth for other transfers.
 
UAC1 and UAC2 are enough different that the device can't switch dynamically between them. In UAC2 it seems all the communications are at high speed even for a 44.1 file. It sort of makes sense because negotiating a high speed link is a little involved and you don't want to switch once engaged. UAC reserves some bandwidth for the audio stream (what they mean by isochronous) so the audio won't get hammered by a disk transfer on the same host. At lower data throughput it probably releases more bandwidth for other transfers.
You are correct. If the Device starts in UAC1, then it probably won't even list 192 kHz as an option in the Descriptors. If the Device starts in UAC2, then it's going to require a disconnect and reconnect or a USB rescan to change to the slower bus speed of UAC1.

However, a Device can have multiple Alternate Interfaces, and that's where different amounts of bandwidth for the Isochronous endpoints are specified. So, when a UAC2 Device switches from 192 kHz to 44.1 kHz, the selected Alternate Settings will be using less bandwidth, leaving the rest for other Devices on the USB.

In other words, the USB Audio Device does not change bus speed, but it does change the percentage of the available bandwidth that it reserves and uses.
 
Here's something some of you without MACs will probably enjoy...!

Since WaveIO is natively supported in OSX and not in Windows, some of you probably wish they had a MAC. (I don't... :D )

There's a USB dongle called EFI-X (V2 or V3, older version like V1.1 only support MAC OSX to a certain version).

This dongle is capable of booting a RETAIL copy of MAC OSX as well as any other PC supported OS like Windows and Linux.

It boots MAC OSX natively (not virtualized and not Hackingtosh) from the retail original copy and installs without issues. Works like a charm but make sure you check the ACL since not all CPUs, Motherboards and GPUs are supported. But the list is pretty good. I believe it requires at least a Core 2 Duo and higher processor and maybe some AMDs as well...

I have a friend in the US using it with V2 and loves it

You can actually go to youtube and look for EFI-X

So this should make some WaveIO fans happy!

Ciao!
Do
 
Here's something some of you without MACs will probably enjoy...!

Since WaveIO is natively supported in OSX and not in Windows, some of you probably wish they had a MAC.

Hmmh. Most of the USB HiRes DAC users out there use the generic Thesycon USB driver under Windows 7.

Is the WaveIO not working with that driver under W7?
 
Many postings suggest that it is a scam? Ripping off others' software from Chameleon et al - see here from Toms Hardware which is a reputable site - Exclusive Report: EFI-X Mac Booter, A Scam?

Must say I wouldn't touch it especially as it costs 175 Euros + shipping and also almost certainly infringes Apple's licence terms.

To infringe on Apple's licence is of course 1000000% true as just farting infringe on it and you might also get sued for iFart! :D

My friend uses the v2 or v1.1 and was going to get v2 on the hype. His experiences are mostly positive not saying there is not any bumps or hickups though... Like I said I'm happy with my PC!

Do