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Old 7th March 2013, 01:59 AM   #11
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Any interest in implementing DSP crossover filters?
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Old 7th March 2013, 07:34 AM   #12
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Good news, but there is no any info of key features of this transport. Is it 32bit , what's max. sampling rate supported, likewise what about DSD support? When 8ch ver will be available?
Thanks.
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Last edited by AndriyOL; 7th March 2013 at 07:43 AM.
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Old 7th March 2013, 09:20 AM   #13
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Man, this is exciting! Finally the wait is almost over Thanks for sharing, Russ!
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Old 7th March 2013, 12:31 PM   #14
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I was intentionally vague about some key features, as I have some firmware coding to do on the prototype.

Still what I can say for sure is that it will at least support the following:

44.1 - 192Khz-24bit playback via I2S and SPDIF.

Features still in development that are expected (but not promised):

2 channel Audio input *and* output up to 384Khz 32-bit.

DSD support (to what degree TBD)

ADC input (because I need to test integration with the ADC)

The great thing is that It is a DIY module, and as such we expect to provide updates and even possibly custom firmware as we can to support the community. To facilitate that I plan on installing the DFU firmware. All of this still needs to be tested.

Cheers!
Russ
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Old 7th March 2013, 01:52 PM   #15
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Sounds great! But I'm interested only with 8 channel 384Khz 32-bit version with DSD support (DSD 128fs or diy DSD512).

Best Regards.
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Old 7th March 2013, 02:52 PM   #16
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What is the expected price?
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Old 7th March 2013, 03:08 PM   #17
Bunpei is offline Bunpei  Japan
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Oh, it's a long-awaited good news!

May I ask a few questions? Please feel free to ignore any of them.

1. "Asynchronous USB 2.0 input module"
Does this mean "USB Audio Class 2.0" compatible or simply "USB 2.0 (High-speed)" compatible?
If it is "USB Audio Class 2.0" compatible, it does require a driver software in Windows environment and does not in Mac OS environment. Is it correct?
If we use it with ASIO compatible players, we can use ASIO4ALL for that purpose?

2. I2S (TTL and LVDS for teleporter)
Does the TTL mean "+5V TTL level" or "+3.3V C-MOS level"?

3. Two extremely low phase noise Crystek clocks for the audio master clocks
Are these clocks of 45.1584/49.152MHz or 90.3168/98.304MHz?
We expected your strong buying power would make them supply 90s MHz pair to you.

4. All digital audio signals (clocks and data) are re-clocked to the audio master clock
I assume you have overcome the 400MHz re-clocking issue of XMOS architecture that a Canadian vendor sometimes blames. I have believed that you would achieve the true re-clocking.

5. I2C control for DAC
Is the USB board configurable to send commands for setting registers in DAC over I2C?

Anyway, congratulations!
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Old 7th March 2013, 03:35 PM   #18
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Quote:
Originally Posted by Bunpei View Post
Oh, it's a long-awaited good news!

May I ask a few questions? Please feel free to ignore any of them.

1. "Asynchronous USB 2.0 input module"
Does this mean "USB Audio Class 2.0" compatible or simply "USB 2.0 (High-speed)" compatible?
If it is "USB Audio Class 2.0" compatible, it does require a driver software in Windows environment and does not in Mac OS environment. Is it correct?
If we use it with ASIO compatible players, we can use ASIO4ALL for that purpose?

2. I2S (TTL and LVDS for teleporter)
Does the TTL mean "+5V TTL level" or "+3.3V C-MOS level"?

3. Two extremely low phase noise Crystek clocks for the audio master clocks
Are these clocks of 45.1584/49.152MHz or 90.3168/98.304MHz?
We expected your strong buying power would make them supply 90s MHz pair to you.

4. All digital audio signals (clocks and data) are re-clocked to the audio master clock
I assume you have overcome the 400MHz re-clocking issue of XMOS architecture that a Canadian vendor sometimes blames. I have believed that you would achieve the true re-clocking.

5. I2C control for DAC
Is the USB board configurable to send commands for setting registers in DAC over I2C?

Anyway, congratulations!
Thanks! I am happy to answer.

1) USB Audio Class 2

2) 3.3V based LVTTL same as ESS DAC and ADC accept/produce.

3) Exploring several possibilities here. More prototyping will be required.

4) This technique I am using should ensure that signals are always aligned with the master clock. I would be interested in reading the experience of the Canadian vendor. If you can please send me more info.

5) Not currently in scope, but I will think it over.

Cheers!
Russ
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Old 7th March 2013, 03:44 PM   #19
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Quote:
Originally Posted by Bassivus View Post
What is the expected price?
It would be difficult to venture a guess at the moment with so many variables still not solved. But as always we will price it reasonably based on the cost to produce the unit. We value the DIY community too much to overprice it.

Cheers!
Russ
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Old 7th March 2013, 05:07 PM   #20
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Hi Bunpei, of course I meant you to respond privately, because I simply do not agree in many respects with the people you refer to.

I understand very well how both the XMOS and ESS I/O schemes work.

https://www.xmos.com/download/final/...ime=1362678408

With the ES9018 the effects of the 400Mhz skew on I2S would not matter as everything is asynchronously re-sampled (not merely re-clocked), but even if you are of the mind that it would matter, re-clocking each signal to the audio master clock solves this issue very nicely.

I will say that if someone credible can definitively show a direct analog effect (at the DAC output) of the 4ns jitter on anything other than a master clock on the analog audio signal (not digital) I will gladly change my view, until then that idea holds no water for me.

Anyway - for this source, it's a complete non-issue. The output is not coming directly from the XMOS chip. And the master clock is definitely not generated by it.

Cheers!
Russ
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Last edited by Russ White; 8th March 2013 at 01:03 AM.
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