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exaU2I - Multi-Channel Asynchronous USB to I2S Interface

When I'm switching from one samplerat/bitrate to another (without pressing stop) in J.River I get an error message. I don't have this problem with other Asio sources. Not a big issue since it's solved by pressing stop and then play, but still something I would like to see fixed.

I will investigate the issue. However your best choice is to use the ASIO driver with J River. The Windows option wising Virtual Audio Cable is available as a backup for players that have no ASIO support - for example Windows Media Player and Windows Media Center.

The disadvantage of using VAC is that you and up with re-sampling unless you re-configure manually VAC every time you use a source with a different sampling rate.
 
I'm almost interesting in hearing more about the cause of hiccups with the standard firmware in Buffalo II. If it's related to high jitter level or not. I haven't bought the new firmware yet and is hesitant because TPA is saying it will increase the tolerance for phase noise/jitter.

You are raising the important question for compatibility between Buffalo II and third party I2S devices. Here is a brief summary of previous posts to this thread regarding this issue:

Supra, Post 533:
I've just imported the first exaU2I USB-I2s device into Australia. Very nice unit and great backup from exadevices.
I'm using it with a Twisted Pear Sabre 2 dac, and using the I2S connection of course.
However I cant get a constant lock on to the dac with any freq over 96K. Works fine at 44, 48, 96 but drops out every 2 secs with 176,192.
I've determined it's not the exadevice, as the same thing happens when using an Evo and Teradak I2S connection.
Even when there is no track selected the "Lock" led on dac flashes every 2 secs when connected via I2S.
It's fine with spdif at all freqs, works very well.

http://www.diyaudio.com/forums/members/bunpei.htmlBunpei Post 541:
TPA might have changed ES9018 register setting for DPLL bandwidth parameter at the same timing when they upgraded previous 80 MHz oscillator to new 100 MHz one.
In my case, two new Buffalo II boards with 100 MHz oscillators shipped this year suffered the similar problems. After replacing the new MCU with old one that came with an old Buffalo II board with 80 MHz oscillator, the problem disappeared.

http://www.diyaudio.com/forums/members/bunpei.htmlBunpei, Post 546:
Just about two months ago. I posted the issue on their support forum.
DPLL Bandwidth setting on B II - Buffalo DAC - Twisted Pear Audio Support
However, I have received no answers from them so far.
Any DPLL Bandwidth parameter other than "default best" is very hard for any transports of I2S output to catch up because the DPLL frequency might be 64 times higher for I2S than that of S/PDIF.

BrianDonegan, Post 554
Hey, I just got your PM this morning and replied. I also just saw this. Russ just posted about it here as well: DPLL Bandwidth setting on B II - Buffalo DAC - Twisted Pear Audio Support So, the uC on the Buffalo is set to use the optimal DPLL setting, which in our testing with both the XMOS eval and our XMOS solution in development, has provided the best and lowest jitter performance.

We have not used this USB interface, so I hesitate to offer an explanation. We have had no issues with high-res material and the current firmware on the Buffalo, or we would have changed it. I would stress that most people using the Buffalo for high-res are not having any issues. If you are having success w/o the firmware chip in place, then the default DPLL settings are what you want, as it can deal with higher jitter from the source (lower jitter rejection).

Running w/o the firmware, however, means you have incorrect DAC mapping for the I2S signals, so that is not good either. We will make a "High Bandwadth" version of the firmware available to those who want it with the less optimal default DPLL. That's totally not a problem. I will add a link to the web site for people to order it (will post an URL when I have it set up).


GLT, Post 555
The real issues is that the ESS 9018 DAC has a 7-step tweakable DPLL setting below the lowest setting available in the older 9008 DAC, and that setting applies to both I2S and SPDIF with SPDIF possibly having a larger BW on the same setting as Mr Bunpei said. I have no doubt that the shipping firmware for the DAC has been tweaked for best performace rather than best customer satisfaction because this is DIY

In summary, the fact is that the Buffalo II firmware change cased compatibility issues with the following I2S devices:

  • Evo
  • Teradak
  • MicroSD Memory Card Transport
  • exaU2I
We are told by Brian Donegan that the unreleased TPA I2S interface and the XMOS evaluation board are working fine. These two devices are not a practical alternative for most users.

I agree with the explanation provided by Bunpei and endorsed by GLT - Any DPLL Bandwidth parameter other than "default best" is very hard for any transports of I2S output to catch up because the DPLL frequency might be 64 times higher for I2S than that of S/PDIF.

I believe TPA have optimized the default Buffalo II firmware for use with SPDIF at the expense of I2S compatibility. It is unfortunate that TPA blames third-party I2S devices for having noisy I2S lines or high jitter.

My position is that the use of any of the fine I2S sources with the alternative Buffalo II firmware will produce less jitter and better subjective results than using Buffalo II with the standard firmware and SPDIF. The SPDIF disadvantage of not having a dedicated clock signal by far outweigh the "drawbacks" of using DPLL Bandwidth setting compatible with I2S.

exa065
 
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A concise summary of how to obtain DSD audio files by ripping them from SACD using SONY PlayStation 3 (of the first generation model) is available on this Japanese blog page (In Japanese).
PC???: SACD???????!!!
The page has a lot of illustrative pictures and useful links.

I think the number of people those who start the ripping and need a good USB interface capable of playing DSD audio files will increase much.
 
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What a complete kit for the BIII of accessories, add-ins boards do we need to order to be able to listen 8ch 32bit 384Khz sources?

This morning I replied to a question posted on Buffalo III - flexibility without compromise. My answer appeared for a short moment and than became unavailable. I am puzzled. exaU2I complements the fine offerings of TPA and it is the only DIY USB to I2S interface that can provide 8 channels at 32bit/192kHz and 4 channels at 32bit/384kHz / DSD64 / DSD128. One would think that Buffalo III and exaU2I provide the magic mix to DIY designers to boldly go where no audiophile has gone before.

Here is my original answer to AndriyOL (reconstructed from memory):

"There is a third-party component that almost meets your requirements. exaU2I will give you the taste of 32bit resolution. The interface supports up to 4 channels at 384kHs and DSD."
 
This morning I replied to a question posted on Buffalo III - flexibility without compromise. My answer appeared for a short moment and than became unavailable. I am puzzled. exaU2I complements the fine offerings of TPA and it is the only DIY USB to I2S interface that can provide 8 channels at 32bit/192kHz and 4 channels at 32bit/384kHz / DSD64 / DSD128. One would think that Buffalo III and exaU2I provide the magic mix to DIY designers to boldly go where no audiophile has gone before.

You should not be puzzled as they (the TPA guys) simply delete all posts that either they imagine as critical in any way or if you mention anything that could be thought of as a competing product :D:D
The TPA guys have stricter censor management than the old iron curtain guys:headbash:
 
Buffalo III and exadevice indeed are great combination! Any plans to let exaU2I available outside the existing country list? I am based in Hong Kong

I apologize for the country list restrictions. We are working hard to expand our manufacturing capacity and support capabilities. Hopefully soon we will be able to expand the country list.

exa065
 
Seems fair to me considering that, in contrast to the exaU21 device, the TPA products are marketed in the commercial sector of DIYaudio.

We will move to the commercial sector when we have more content and more products. It will be disrespectful to the community to move one single thread for the questionable benefit of censorship. Alter all, facing critical views like yours helps us to stay strong, honest and credible.
 
simply delete all posts that either they imagine as critical in any way

I am going to have to chime in here (sorry). The following is a list of reasons we might delete a post:

- posts promoting competing products... that only makes sense
- posts that are technically inaccurate or misleading, which may lead users to make mistakes

We do not delete posts that are simply critical.
 
Member
Joined 2009
Paid Member
We will move to the commercial sector when we have more content and more products. It will be disrespectful to the community to move one single thread for the questionable benefit of censorship. Alter all, facing critical views like yours helps us to stay strong, honest and credible.
I'm sure you could decide not to censor also in a thread in the commercial sector. I would find that more honest, credible and consistent with community rules.
Anyway, my 'critical view' has nothing to do with your device so I'm OT. Just lurking around for OSX support:)
Cheers,
Nic
 
Wow. How do you buy the Burwen software?


You can get a key at his site and download the software. I am waiting for the Audio Splendor to become available. The Bobcat software is available now $469. The Audio Splendor will be ~1,200.

BBTB_Download


Not affiliated with Burwen software.

The Audio Splendor is an expanded version that will create up to 7.1 from 2 ch recordings. Bobcat will do 5.1.

Some information from Dick on the software and multi ch:

I make 3 channels in front by adding left and right into the center, each at -13 dB. To compensate narrowing of the image, left and right are blended out of phase at -22 dB. Both AUDIO SPLENDOR and BURWEN BOBCAT TONE BALANCER have around 40 fixed mixes one of which does this. AUDIO SPLENDOR also has a 7 to 7 mixer variable in 0.1 dB steps.

Other systems for enhancing stereo imaging use combinations of mixing and delays and do nothing to fix bad high frequencies. In addition to tonal balancing, my system fixes high frequencies by adding unique high frequency reverberation that no other company has and does not occur in real rooms. I strongly recommend 5 channels instead of 3. My system adds ambience into both rear and front channels to make everything more musical. The instruments are still up front where they should be........

Both AUDIO SPLENDOR and BURWEN BOBCAT TONE BALANCER have an all-channel master volume control. Tone calculations are made at 64 bits floating point and reverb at 32 bits floating point......

Yes. Sample rate conversion is basically interpolation to get more samples. You can play CDs at 88.2 kHz, 24 bits. (The Audio Splendor can work up to 192k/24 bit IIRC. I didn't go into a lot of detail with him about higher clock freq so this info may be incomplete), [/quote


So the software will do up sampling of CD's, includes the functionality of the Cello Audio Pallette, go from 2 to 7.1 from CD source. It add a small amt of hi freq reverb. I am in the process of transferring my CD's to the pc.

It does reequire you use the Windows Media Player & Excel(the software is written in excel workbooks and is a WMP media player. It will also work with MP3's. I am using a FLAC converter for FLAC files I have. The settings for a recording can be stored, so no need for program eq after first setting. However the settings are stored as metadata so the original file is always available.

BTW I am not affilated just looking to become a customer.
 
I am going to have to chime in here (sorry). The following is a list of reasons we might delete a post:

- posts promoting competing products... that only makes sense
- posts that are technically inaccurate or misleading, which may lead users to make mistakes

We do not delete posts that are simply critical.

Hi Brian,
I respect your space. It was the first time I allowed myself to answer a direct question in a balanced way. I won't intrude again.

I certainly taught that exaU2I complements your offerings by filling in a missing piece of the puzzle. What other computer interface can offer the 32bit/384kHz resolution and the multichannel capabilities of exaU2I?

I don't think my answer was misleading or inaccurate. I am not sure what was the line that I overstepped.

exa065
 
I'm sure you could decide not to censor also in a thread in the commercial sector. I would find that more honest, credible and consistent with community rules.
Anyway, my 'critical view' has nothing to do with your device so I'm OT. Just lurking around for OSX support:)
Cheers,
Nic

Hi Nic,
Our experience is mostly Windows. Getting into Objective C, Cocoa UI and CoreAudio is a real adventure for us. At the present time we enjoy the DIY journey.
 
Hi Nic,
Our experience is mostly Windows. Getting into Objective C, Cocoa UI and CoreAudio is a real adventure for us. At the present time we enjoy the DIY journey.

Ever consider some help with the OSX drivers?

If so try contacting Rob Robinson at Pure Music CHANNEL D - Contact

Maybe there is something you two can work out? I would think the business that would be generated from the first to deliver a Mac solution would be very profitable. :cool:

-Steve
Quietly waiting for a OSX/USB/I2S solution.......
 
If I may... I hope Axa will not object that I like posting here:)

I feel need to update you on the latest I find out regarding the problem I outlined here before. The problem was that I could not find software crossover for OSX so I did it through the use of Jack and Logic. Crossover within Pure Music was fine but I needed something else in order to play streaming music or simply just to pop CD, since I was not able to do it in Pure Music.

Now life gets much simpler. Pure Music implemented play through option, which functions sort of like Jack. It allows you to select Pure Music as an output device. That way you could use any other player to play through Pure Music, where you might have set up crossover and Eq filters. That is much easier and simpler than what I was doing before with Jack and Logic. That way you could enjoy your digital files, streaming and CD all through the same set up on Pure Music player. We all do that, we enjoy our Flac files, but we also need simple background music as well.

So Axa, here is one more voice for OSX driver, hehe