thats because those outputs on the buffalo II that you mention have nothing to do with i2s, they are the i2c connections for connecting to volumite or another mcu
as for the i2s though, the i2s header with clk, D1, D2 and ground are listed in the manual quite clearly.
Source GND → GND
Source Bit Clock → DCK
Source Word Clock(LRCK) → D1
Source Data → D2
as for the i2s though, the i2s header with clk, D1, D2 and ground are listed in the manual quite clearly.
Source GND → GND
Source Bit Clock → DCK
Source Word Clock(LRCK) → D1
Source Data → D2
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I would agree with this, because any interest in it and also any functionality provided by it can now simply be provided by thunderbolt/lightpeak by adapters; there will not be a lot of money going that direction any further its dead in the water imo, new macs, the vast majority of firewire ports, are already phasing it out. there will of course continue to be companies that have spent a lot of developing quite good technologies using it, but they will be the minority and will mostly already be working on something else
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qusp...
Thunderbolt is backwards compatible with Firewire and USB3, that is, FW and USB3 formats can be sent over Thunderbolt. So even if Mac does not offer FW ports anymore, one can run FW out of Thunderbolt, and plug in a FW device via either a Thunderbolt to FW cable, or a Thunderbolt to FW adapter.
This is critical for all of those folks who may FW DACs and interfaces, especially in pro audio.
In any case, I do agree that new developments for audio interfaces will go away from FW in the long run.
Thunderbolt is backwards compatible with Firewire and USB3, that is, FW and USB3 formats can be sent over Thunderbolt. So even if Mac does not offer FW ports anymore, one can run FW out of Thunderbolt, and plug in a FW device via either a Thunderbolt to FW cable, or a Thunderbolt to FW adapter.
This is critical for all of those folks who may FW DACs and interfaces, especially in pro audio.
In any case, I do agree that new developments for audio interfaces will go away from FW in the long run.
Oh ! thank you for the response ,i should have known the I2S on BuffaloII was a I2S output ., having used it for volumite....
did you read my post? see below. by adapter i meant ...well...adapter for usb X, firewire X00, PCI-E, HDMI etc etc etc. otherwise you would be using thunderbolt directly; no adapter
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Yes, I'll implement external XO options besides local ones, and I want to be isolated from USB mst probably using AC-coupled differential signaling. I'll see if external sources must be differential as well or not... For this job I'll use SMAs like this one instead of uBNCs (trying to avoid 90 degree turns in signal's paths).
Regards,
L
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Since FW...
is supported by Thunderbolt on the computer side, why would it be "dead in the water" on the peripheral side?
Not that it really matters, the real point is to make sure folks understand that FW peripherals (and USB) are supported by Thunderbolt computer outputs.
I have no preference for FW or USB for a DAC interface, as either can produce the best possible results with proper implementation. Although most FW DACs are not asynchronous (the only exception I know of is that Metric Halo claims to run their own async FW interface) as they use the PLL based DICE approach... USB2 HS, with a good async interface can offer "perfect" performance, except, possibly (but we really do not know yet) in regards to isolation from computer borne noise issues...
is supported by Thunderbolt on the computer side, why would it be "dead in the water" on the peripheral side?
Not that it really matters, the real point is to make sure folks understand that FW peripherals (and USB) are supported by Thunderbolt computer outputs.
I have no preference for FW or USB for a DAC interface, as either can produce the best possible results with proper implementation. Although most FW DACs are not asynchronous (the only exception I know of is that Metric Halo claims to run their own async FW interface) as they use the PLL based DICE approach... USB2 HS, with a good async interface can offer "perfect" performance, except, possibly (but we really do not know yet) in regards to isolation from computer borne noise issues...
dead in the water as in ceased further development and now just legacy support, why would you develop something new using it?, forcing the high end of your customers (traditionally those looking at firewire interfaces are not entry level), who probably already have a thunderbolt equipped mac, to buy an adapter and limit bandwidth. usb 3.0 is only just released and its already dead imo, that depends on how quickly intel roll out chipsets for PCs of course and what agreement they have with apple, though it looks as though they will simply push ahead with lightpeak hybrid copper/optical connections.
anyway we are OT, its exciting times!! i'm waiting for the first external thunderbolt audio DSP and just bought a crucial M4 ssd
@Lorien w.fl bnc work just fine for clock distribution and there are also larger type smd bncs developed for exactly this purpose, thats whats underneath the local clock on the ackodac in case you want to do synchronous master clocking (pads for it anyway). also they make the sma quite often in right angle form. i don't think you have anything to worry about, why not stick with something so that people do not have to change again after just buying the cables?
anyway we are OT, its exciting times!! i'm waiting for the first external thunderbolt audio DSP and just bought a crucial M4 ssd
@Lorien w.fl bnc work just fine for clock distribution and there are also larger type smd bncs developed for exactly this purpose, thats whats underneath the local clock on the ackodac in case you want to do synchronous master clocking (pads for it anyway). also they make the sma quite often in right angle form. i don't think you have anything to worry about, why not stick with something so that people do not have to change again after just buying the cables?
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This is very interesting. How do you know that the Ayre QB-9 is designed this way? Or, maybe I should ask: Where do I go to find schematics or other internal details of the QB-9? I have the Manual, but it's not quite that detailed.
I live in
Boulder, and was friendly with Ayre's former sales/marketing guy, Steve. Every once in awhile I would be at their office and he would show me what's new. So I got to see under the hood of the QB-9 back when it was first being released.
Ayre head honcho Charlie Hansen has also described it in some detail on various Audio Asylum posts.
They power the USB receiver (on a separate board) from the USB bus, and then power the rest of the DAC from the onboard linear power supply. The USB receiver board is isolated from the DAC/output board by optocouplers. The clocks are on the DAC board, near the DAC chip, the the masterclock is sent back to the USB receiver.
This approach powers the clocks from the clean onboard supply, and isolates the computer and USB receiver from DAC/output board.
Boulder, and was friendly with Ayre's former sales/marketing guy, Steve. Every once in awhile I would be at their office and he would show me what's new. So I got to see under the hood of the QB-9 back when it was first being released.
Ayre head honcho Charlie Hansen has also described it in some detail on various Audio Asylum posts.
They power the USB receiver (on a separate board) from the USB bus, and then power the rest of the DAC from the onboard linear power supply. The USB receiver board is isolated from the DAC/output board by optocouplers. The clocks are on the DAC board, near the DAC chip, the the masterclock is sent back to the USB receiver.
This approach powers the clocks from the clean onboard supply, and isolates the computer and USB receiver from DAC/output board.
Very impressed.
I own an April Music Stello U3 which seems similar.
I just wanted to say that XMOS boards seem to be perfectly seen under Linux.
If:
- linux kernel is >=2.6.37
- AND alsa version >= 1.0.23
then, USB Audio Class 2.0 is fully implemented.
You can run alsa-info script to report information on a Linux system. Here is what reports the Stello U3.
I assume your board can achieve excellent results on Linux. I use my XMOS based converter on a dedicated linux plugcomputer. Cheap but very efficient with MPD for a great and natural sound.
I own an April Music Stello U3 which seems similar.
I just wanted to say that XMOS boards seem to be perfectly seen under Linux.
If:
- linux kernel is >=2.6.37
- AND alsa version >= 1.0.23
then, USB Audio Class 2.0 is fully implemented.
You can run alsa-info script to report information on a Linux system. Here is what reports the Stello U3.
I assume your board can achieve excellent results on Linux. I use my XMOS based converter on a dedicated linux plugcomputer. Cheap but very efficient with MPD for a great and natural sound.
Thank you for the positive info regarding XMOS interfaces under Linux. In my years of experience with Linux one thing I've learned is that should work (meaning there is full software support for it) does not always equate to does work, so I was a bit skeptical about the promised PnP functionality of USB AC2.0 under Linux. Perhaps I'm still not 100% convinced that all USB AC2.0 compliant interfaces work without a hitch under Linux. Call me cynical if you wish... 
I am no
expert on this, but I think that the player software with Linux may have somethign to do with whether or not a USB2 HS interface, like XMOS based USB devices will work perfectly. Note, that just because something works (music comes out) does not prove that it is actually working perfectly (bit perfect).
If using mpd, I would contact the mpd developer(s) to ask what their experience is with XMOS based USB to be sure.
expert on this, but I think that the player software with Linux may have somethign to do with whether or not a USB2 HS interface, like XMOS based USB devices will work perfectly. Note, that just because something works (music comes out) does not prove that it is actually working perfectly (bit perfect).
If using mpd, I would contact the mpd developer(s) to ask what their experience is with XMOS based USB to be sure.
Well, maybe you could see here. They may help you.
This is only my personal tries: for the story, I've tried several DAC/Transport on Linux to replace my good old CEC CD player: Arcam rDac, HRT II+, VDAC -I and the combo April Stello U3 (XMOS)/VDAC. The last one is far far superior.
And since:
1.- XMOS are USB Audio Class 2.0 boards
2.- USB Audio Class 2.0 is a documented standard
3.- USB Audio Class 2.0 is implemented on recent Linux distributions (no driver needed) even if alsa dev do not communicate much about it
4.- XMOS developpment boards were said to play on Linux, as well as Ayre QB-9, Wavelenght Wavelink HS, SOtM dx, Calyx DAC 24/192 (all XMOS based). sonore.us has made some tests.
so I would'nt be afraid with every XMOS based devices.
An issue could come more from the usb controller than the OS. With USB Audio Class 2.0, when playing 24 bits/192 kHz flac files (high flow), it's better to not share the USB controller with for example an USB HDD. That's why I've dedicated my plugcomputer (equipped with 4 USB ports) only to one USB device: the XMOS Spdif transport Stello U3.
No clics, no issues.
Of course I do not use any logical mixer, the USB XMOS is hardware adressed by alsa in mpd. And with a dedicated plugcomputer: there are less interrupts: no other usb ports used (printer mouse..), no graphical system.
I've played some classical strings pieces to an EMI concertist friend. She was amazed and asked me where to buy it ;-)
This is only my personal tries: for the story, I've tried several DAC/Transport on Linux to replace my good old CEC CD player: Arcam rDac, HRT II+, VDAC -I and the combo April Stello U3 (XMOS)/VDAC. The last one is far far superior.
And since:
1.- XMOS are USB Audio Class 2.0 boards
2.- USB Audio Class 2.0 is a documented standard
3.- USB Audio Class 2.0 is implemented on recent Linux distributions (no driver needed) even if alsa dev do not communicate much about it
4.- XMOS developpment boards were said to play on Linux, as well as Ayre QB-9, Wavelenght Wavelink HS, SOtM dx, Calyx DAC 24/192 (all XMOS based). sonore.us has made some tests.
so I would'nt be afraid with every XMOS based devices.
An issue could come more from the usb controller than the OS. With USB Audio Class 2.0, when playing 24 bits/192 kHz flac files (high flow), it's better to not share the USB controller with for example an USB HDD. That's why I've dedicated my plugcomputer (equipped with 4 USB ports) only to one USB device: the XMOS Spdif transport Stello U3.
No clics, no issues.
Of course I do not use any logical mixer, the USB XMOS is hardware adressed by alsa in mpd. And with a dedicated plugcomputer: there are less interrupts: no other usb ports used (printer mouse..), no graphical system.
I've played some classical strings pieces to an EMI concertist friend. She was amazed and asked me where to buy it ;-)
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