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Old 20th February 2011, 11:35 AM   #41
SunRa is offline SunRa  Romania
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This looks most interesting. I have a couple of questions though..

1. How will it be priced
2. Did you managed developing UAC 2.0 drivers for this thing in windows?

Thanks!
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Old 20th February 2011, 12:12 PM   #42
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Quote:
Originally Posted by NeoY2k View Post
Hello,
Thanks for your message on my previous thread.
[ ...]
FireWire was an excellent idea. It (almost) never was correctly implemented. Compatibility issues were paramount. Finally, even Apple ditched it out of most it's products, even Macbook Pros!
Really? Mine (2010) has FW800, all current Macbook Pros have FW800, the Minis have FW800 (FW800 is back-compatible to FW400).

FW is processor independent, manages itself, and needs no CPU cycles. Any two FW devices can talk to each other (ie , no computer need be involved, Camcorder direct to Hard Drive, for example).

Compatibility? Easy to solve. There was a bad chip some lowest-cost producers of peripherals tried to use that did not follow the IEEE 1394 protocol. Such a chip would be junk in any application (nor is it a "Firewire" chip since to use that trademark instead of IEEE 1394, you needed to comply with Apple's spec fully, amongst other things).

Check to see that your product used the Oxford chipset. Yes? No problems. Next ...

Many of the issues with audio and USB centre around the need for USB to be managed by the CPU. There is no need for asynchronous FW, there is a (perceived) need for async USB, so there must be a problem to solve.

USB is good, but far from perfect, and I see a lot of effort solving problems that should not exist in the first place.

That is not to say that FW should be the solution, but to say "it's dead" without understanding why it was the first choice for audio in the first place isn't helpful.

It was developed specifically for Audio and Video data transport, while USB was developed to be as versatile as possible, the spec incorporating many features intended to interface other products that specifically harm the integrity of audio data streams.

Now, we get to solve them because it's $3 cheaper a box for a USB chip than a FW chip. Async USB to I2S costs less than $3 to implement, right? So no need for FW then.
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Last edited by Johnny2Bad; 20th February 2011 at 12:39 PM.
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Old 20th February 2011, 01:34 PM   #43
exa065 is offline exa065  Canada
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Quote:
Originally Posted by UnixMan View Post
What about Linux/ALSA driver support?
Eventually we will develop Linux drivers. It depends on the demand for the board. At the present time we try to understand what feature are in demand.
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Old 20th February 2011, 01:47 PM   #44
exa065 is offline exa065  Canada
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Originally Posted by qusp View Post
i would also suggest after looking at your board that perhaps in a revision you provide an easy way of supplying your own regulation/power. us diyers often have our own favorites. also the smd micro bnc connectors from hirose are excellent for hispeed impedance controlled interconnects
For the next revision I will have the option for external power supply.
I had the option and I removed it. In my opinion the benefit will be purely psychological. I've already cleaned the power for the sensitive circuits.

Micro BNC can be a add-on board for the current design. Would that be OK?
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Old 20th February 2011, 02:11 PM   #45
exa065 is offline exa065  Canada
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[QUOTE=AR2;2475368]This is absolutely great project, and something of great interest for myself. I am in the middle of designing new active 4 way system and I have been researching a lot on the subject. I do like many aspects of this project. I will be using ESS chip as well. Here are few suggestions:

1. Definitely OSX support....

2. FW support .....

3. ASIO drivers - Yes, perfect!

4. Crossover modules .....

5. Crossover .....

6. Lastly - stand alone DSP....

Best luck with your development, and I assigned myself to the waiting list!


AR2,
Thank you for the feedback. I will try to make these features available via in-house development or via collaboration with third parties. It is not going to happen fast. I will release the product with the current feature set. Software upgrades will enable some of the requested capabilities.

The addition of extra hardware power is a serious and very interesting topic and I would like to move it to a new discussion thread. This will be a different device Ė not the exaU2I.
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Old 20th February 2011, 02:32 PM   #46
gogu is offline gogu  United States
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Hi exaU2I,
It looks very interesting, however I have a few questions:
1. Is the ASIO driver protocol 2.1?
2. Is it multi-client capable ie, can you use it with 2 applications (player + VST host - like plogue bidule or cubase) at the same time? This is very important for DRC.
3 Is the hardware working with other USB ASIO drivers like CEntrance or Ploytec?
Thank you.
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Old 20th February 2011, 03:29 PM   #47
exa065 is offline exa065  Canada
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Quote:
Originally Posted by glt View Post
A couple of comments/questions:

1- Any thoughts of using bulk mode transfer instead of iso-asynch?
2- In your testing with Sabre32, are you using the lowest setting for DPLL?
I have no thoughts at all about changing the USB implementation. I am happy with it - why should I change it? Iíve taken the road less travelled and I arrived on time.

exaU2I wonít get any better if I change the USB mode. It will get worse. I will focus on drivers / software improvements after I release the product.

Om my ES9018 DAC I use the chip default settings for everything. The goal was wide compatibility with Sabre32 and other DACs.
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Old 20th February 2011, 03:57 PM   #48
exa065 is offline exa065  Canada
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Quote:
Originally Posted by gogu View Post
Hi exaU2I,
It looks very interesting, however I have a few questions:
1. Is the ASIO driver protocol 2.1?
2. Is it multi-client capable ie, can you use it with 2 applications (player + VST host - like plogue bidule or cubase) at the same time? This is very important for DRC.
3 Is the hardware working with other USB ASIO drivers like CEntrance or Ploytec?
Thank you.
The ASIO implementation supports playback only. I am not sure which ASIO 2.1 functions affect playback. If there is something missing for your applications within we should be able to add it.

The driver is not multi-client capable. I've used ReaRoute to chain VST hosts. The driver worked fine with Reaper. Please contact me to discuss your configuration.

exaU2I is a piece of proprietary hardware. It won't work with any other drivers. I guess there is a price to pay if you want top performance. You get the multichannel bit-perfect 32 bit / 352.8kHz, the jitter elimination techniques and the galvanic isolation. You loose wide compatibility.

exaU2I is an alternative device. It deliverers top performance but it does things differently.
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Old 20th February 2011, 06:20 PM   #49
exa065 is offline exa065  Canada
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Guys,

I cannot be of any help on the FireWire vs. USB discussion. There is more than one way to skin a cat. In my opinion there arenít any technological limitations in my USB implementation. Nothing will change in the output I2S stream if I use FireWire. It is a matter of convenience and compatibility to use one or the other. I admit FireWire is cool.

Regarding the various USB modes of operation Ė this discussion is relevant for traditional USB implementations. I donít rely on the USB to do any synchronization. I have a proprietary solution. What matters is that exaU2I is the host, and the PC is the slave. Maybe thatís why I did it with a PC. I donít want to enslave Macs.

So exaU2I (the FPGA core) controls the data flow over USB. Later it may be over FireWire. The FPGA makes sure that USB data has arrived and is uncorrupted in the exaU2I memory buffer. The FPGA makes sure that the buffer never gets empty. If Windows is terribly busy, sometimes the buffer does get empty. For cases like that I have an LED light to indicate an error. A parallel FPGA process reads the memory buffer, clocks the data with one of the two low-jitter quartz oscillators and sends it out in I2S format. This process will go well if the input stream transport (USB or something fancy) is faster than the output stream.

With other words I am confident I donít need to reconsider the USB mode of operation or the use of alternative transport because I know that I can fill up the buffer faster than it is emptied. Remember these high-school math problems: ďA swimming pool is filled up by one pipe delivering X litters per second and drained out by 3 drain pipes taking out Y litters per second. Calculate how long will take before the pool gets empty.Ē I just solved one of these math problems.

For the benefits of the users that are interested to try the coming release of exaU2I we should focus on the use of the device. How are you going to use it guys? What DAC boards do you have?

Is anybody listening to multichannel 192 kHz recordings? Thatís how I use the device. I have Fubar2000 and J. RiverMedia Center. I use an old-fashioned PC because I know how to make it to do anything. The only thing I care about is sound quality. I use 4 speakers and I mix 5.1 and 7.1 to quarto. One day I will build the remaining four speakers. I am really excited about multichannel; there are recordings out there that are mixed in 5.1 with the audiophile in mind. Stereo is not the ultimate thing for me any more. Of course I listen to stereo 44.1 kHz recordings but I donít up-mix stereo and I donít up-sample.

Cheers,

exa
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Old 20th February 2011, 07:20 PM   #50
ejaouen is offline ejaouen  France
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your device as it is now is near perfect and fills a precise niche and task a lot of people here (as I) were waiting for... No problem with a well implemented USB solution for me...
I am linux only user because linux has BRUTEFIR (real time FFt convolution filter engine) and I am making a multiway (stereo) DAC (for 4 way active crossover).

I am sure a lot of people would need ALSA linux drivers : peufeu here has a device like yours but based on the Nexys2 board and linux (you should really be in contact). I am pretty sure a would be interested in buying also you board.
The alsa developper guys are reachable and open : getting them to make the driver would be easy I think.
I would buy instantly your board if it had alsa linux driver...
I am interested in only 44100hz but personnaly with 8 to 16 channels.
I would love a way to combine 2 of your boards to have 16 channel totally in sync (8 channel per speaker side) but it is probably already doable with JACK server in linux.
Playback only is perfect for me and a lot of people here.
I will use many pcm1794 dac ics and would love it if you had a board with 8 (or 16 with dual mono mode possibility) of them already soldered on it.
(A not to expensive board with the ESS 32bit top of the line in 8ch output would also be very interesting to me...) What could be interesting concerning price and performance would be a new board of yours with the ESS 8ch dac also on it.
I also favor integrated power regulation in the boards as you did in you proto board too, and for everyboards.

So personnaly only ALSA linux driver are missing... All the rest is already near perfect as it is.
Thanks in adavance for your time and dedication
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