exaU2I - Multi-Channel Asynchronous USB to I2S Interface - Page 115 - diyAudio
Go Back   Home > Forums > Commercial Sector > Manufacturers > exaDevices

exaDevices World-class audio devices for do-it-yourself projects from exaDevices

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 5th July 2012, 03:54 PM   #1141
Account disabled at member's request
 
Join Date: Sep 2007
Location: Multiple...
Quote:
Originally Posted by exa065 View Post
Wave IO is 24bit, exaU2I is 32 bit. The matters when DSP processing (including software volume control or oversampling) is applied by the player. It is also a major advantage on Mac, where Integer mode is a problem.

exaU2I can go twice as high when it comes to sampling rate (384kHz), and this creates opportunities for oversampling. It also makes it possible to play DXD studio masters files.

We have control over the drivers, and this gives exaU2I an unfair advantage.

In my opinion jitter is a major issue with XMOS. Here is a post by JarekC -TAS1020B-based Asynchronous USB to I2S/SPDIF converter 24bit/96kHz. According to Larry, an XMOS employee:

" any external clock is resampled to 400MHz If you tie I2S signals BCLK LRCLK and DATA to a low-jitter external clock on the XMOS device, this will introduce a jitter in the order of one to two 2.5ns (400MHz) cycles"

exaU2I is 50 times better when it comes to jitter. In general FPGA cores provide much more accurate timing than CPUs.

Regards,
exa065
Even if the WaveIO only runs up to 192k/24bit it could (can) easily have been reprogrammed and supported 384k/32bit and DSD - a hex file with support for 384k/32bit and DSD for the reference design exists..

The referenced XMOS info from "forums" do not match the datasheet informations for the newer and actual XMOS chips I have referenced.

With regard to jitter and XMOS designs vs. exaU2I I would not bet on the exaU2I to be the best, and stating that exaU2I is 50 times better are quite a strange way of marketing.

When I tested exaU2I vs. XMOS it was the 352.8kHz/32bit mode witch is the most important for me that the XMOS design performed without doubt better.
  Reply With Quote
Old 5th July 2012, 04:22 PM   #1142
diyAudio Member
 
Join Date: Nov 2011
I have converter by JarekC and now waiting for XMOS. Maybe Ill try EXA in future also. Also things like 50 times better 500% faster dont convince me that much (no offence). I still have doubts if PC can be transformed into lets say "high end" hehe. Can we say for sure that in such chain converter is absolute brain of all operations and we are isolated from all garbage from PC, noises, power supply, not real-time system, etc?
Lets say we feed converter by batteries and send signal by USB cable with cut powers supply wires (only data signal). Then we need very good converter and thats it? or its not that simple?
RayCtech again, could you please elaborate what "better" means? Can you describe what aspects etc?

Last edited by zibra; 5th July 2012 at 04:24 PM.
  Reply With Quote
Old 5th July 2012, 05:08 PM   #1143
exa065 is offline exa065  Canada
diyAudio Member
 
Join Date: Feb 2011
Quote:
Originally Posted by RayCtech View Post
With regard to jitter and XMOS designs vs. exaU2I I would not bet on the exaU2I to be the best, and stating that exaU2I is 50 times better are quite a strange way of marketing.
2.5ns /50 = 50ps - the measured exaU2I jitter. Our jitter measurements are not that precise. Can you provide any approximate or indirect Jitter measurements for WaveIO?
Quote:
Originally Posted by RayCtech View Post
When I tested exaU2I vs. XMOS it was the 352.8kHz/32bit mode which is the most important for me that the XMOS design performed without doubt better.
Then the best path forward for you is to continue with the XMOS design. Perhaps you can show how others can repeat you results. Please do this on your own thread.
Quote:
Originally Posted by RayCtech View Post
The referenced XMOS info from "forums" do not match the datasheet informations for the newer and actual XMOS chips I have referenced.
Can you provide facts that will confirm or disprove that " any external clock is re-sampled to the XMOS internal clock"


Quote:
Originally Posted by RayCtech View Post
Even if the WaveIO only runs up to 192k/24bit it could (can) easily have been reprogrammed and supported 384k/32bit and DSD - a hex file with support for 384k/32bit and DSD for the reference design exists.
The discussion here is about specific commercially available devices - WaveIO and exaU2I. They can be acquired and produce predictable and verifiable results. Both devices come with excellent customer service. Therefore they can be used for real projects. Things that "exist", "could" or "may" be done belong to different threads.
__________________
exaDevices.com | exaSound.com
  Reply With Quote
Old 5th July 2012, 05:30 PM   #1144
exa065 is offline exa065  Canada
diyAudio Member
 
Join Date: Feb 2011
Quote:
Originally Posted by zibra View Post
things like 50 times better 500% faster dont convince me that much (no offence). I still have doubts if PC can be transformed into lets say "high end" hehe.
There was a specific question, and I provided a specific answer.
What are the things that convince you much? I can try to help.

Quote:
Originally Posted by zibra View Post
"Can we say for sure that in such chain converter is ... and we are isolated from all garbage from PC, noises, power supply, not real-time system, etc?"
-Yes

Regards,
exa065
__________________
exaDevices.com | exaSound.com
  Reply With Quote
Old 5th July 2012, 05:41 PM   #1145
diyAudio Member
 
Join Date: Nov 2011
I just wonder if human perception can catch such things like jitter 20ps vs 2ns. I would like to hear more realistic impressions of comparisions between devices, not only "I plugged xxx and it sounds much better" - such sentence doesnt bring any info. on the other hand I assume that audio is very subjective and everybody hear different. The best possible way is to check it out by myself
Thats why Im waiting for XMOS to compare it on TAS based DIY converter. If I hear audible positive difference maybe Ill try Exa. Problem is much higher cost and tax possibilities as I live in EU. that would be 600 USD for unknown "improvement"
  Reply With Quote
Old 5th July 2012, 05:49 PM   #1146
Account disabled at member's request
 
Join Date: Sep 2007
Location: Multiple...
Quote:
Originally Posted by exa065 View Post
Can you provide facts that will confirm or disprove that " any external clock is re-sampled to the XMOS internal clock"
I re-clock I2S for both exaU2I and XMOS designs with a external isolated audio grade clock (synchronous from/with the DAC masterclock). Thus jitter for both designs will be down in the 1p region. Of course the re-clock / clock hardware cost is higher than the USB -> I2S devices.
  Reply With Quote
Old 5th July 2012, 06:04 PM   #1147
diyAudio Member
 
Join Date: Apr 2008
Human hearing is much more than FR measurement and you will be surprised to witness what a trained hearing can do. I have seen it( because I could not hear anything)- a friend who is a mastering engineer could identify 10/10 whether the digital signal was coming from a hard drive or an SSD and the change was done in the other room. And that is on the most sophisticated equipment that can be bought at the moment.

The exaU2I is absolutely worth the price and if you do a search you could not find someone who has found a better device(at least I haven't come across), the only thing is that is for DIY and doesn't come in a fancy box, I2S only too. No one can guarantee that it is the BEST(don't we all want that?!?!) but it if you can squeeze the best from it it will make you happy. Not going to make a mini system sound like mastering equipment though.

RayCtech is on another level for sure.
  Reply With Quote
Old 5th July 2012, 06:11 PM   #1148
tsiros is offline tsiros  Greece
diyAudio Member
 
tsiros's Avatar
 
Join Date: Jun 2012
Location: Patra, Greece
Send a message via MSN to tsiros Send a message via Skype™ to tsiros
Quote:
Originally Posted by Nikola Krivorov View Post
a friend who is a mastering engineer could identify 10/10 whether the digital signal was coming from a hard drive or an SSD and the change was done in the other room.
so you imply an SSD reading the data produces a different result than an HDD?

that's, simply, impossible.

if they could tell which drive did the reading, it must have been something else - not the sound - that was different.
  Reply With Quote
Old 5th July 2012, 06:24 PM   #1149
diyAudio Member
 
Join Date: Apr 2008
I knew you would say that, I did not hear anything. But when the notes were checked it was 10/10. 4 times it was the SSD feeding the DAC and 6 times the HDD, random. Go figure.

Have a look at this, I find it interesting, but listen to it till the end. She's DEAF.

Evelyn Glennie shows how to listen | Video on TED.com
  Reply With Quote
Old 5th July 2012, 07:46 PM   #1150
diyAudio Member
 
Join Date: Nov 2011
Quote:
Originally Posted by Nikola Krivorov View Post
I knew you would say that, I did not hear anything. But when the notes were checked it was 10/10. 4 times it was the SSD feeding the DAC and 6 times the HDD, random. Go figure.

Have a look at this, I find it interesting, but listen to it till the end. She's DEAF.

Evelyn Glennie shows how to listen | Video on TED.com

Well Im amazed that your friend didnt gather 1 million yet

James Randi Offers $1 Million If Audiophiles Can Prove $7250 Speaker Cables Are Better

OK, back to converters - I would really appreciate what audible differences are between WaveIo and Exa from ppl who have tested both. I got quite nice headphone system where I can hear a lot of things and Im still in search of the best solution for chain with PC

Last edited by zibra; 5th July 2012 at 07:49 PM.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Ultimate USB to I2S interface sampler Digital Source 206 30th January 2012 04:45 PM
High Resolution Multi-Channel Digital Interface Brian Brown Digital Source 34 15th January 2008 07:48 PM
interface I2S with USB mermoz Digital Source 0 21st February 2003 11:34 AM


New To Site? Need Help?

All times are GMT. The time now is 08:30 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2