iFi audio Pro iDSD (Official) - NEW Firmware - MQA and more.

[skootb]

I got an iDSD today and have been using it with my Noble Audio Katana CIEMs. I'm liking it enough that I think I'm going to sell my Hugo 2. I'm not saying it's better than the Chord, but it is different and really good. I don't need anything portable and after a few hours listening to the tube output on the iDSD, I definitely like it.

I am having 1 issue, though. I am using the Onkyo HF player on my iPhone with the apple camera accessory and then USB from that to the iDSD. My phone is constantly "losing" the iDSD. If I pause a track, the phone doesn't see the iDSD anymore. Unplugging the usb and plugging it back in does nothing. I have to turn the iDSD off and then back on to get the phone to see it again. Is this a known issue?

 

[doggiehowser]

oops my bad - the link went to spam folder.

 

[gordec]

I got an iDSD today and have been using it with my Noble Audio Katana CIEMs. I'm liking it enough that I think I'm going to sell my Hugo 2. I'm not saying it's better than the Chord, but it is different and really good. I don't need anything portable and after a few hours listening to the tube output on the iDSD, I definitely like it.

I am having 1 issue, though. I am using the Onkyo HF player on my iPhone with the apple camera accessory and then USB from that to the iDSD. My phone is constantly "losing" the iDSD. If I pause a track, the phone doesn't see the iDSD anymore. Unplugging the usb and plugging it back in does nothing. I have to turn the iDSD off and then back on to get the phone to see it again. Is this a known issue?

Could be a bad USB OTG cable. You have another one to try? Also have you tried with other music apps? When I do iPad pro to pro iDSD via cck, it's fine in Tidal.

 

[skootb]

Could be a bad USB OTG cable. You have another one to try? Also have you tried with other music apps? When I do iPad pro to pro iDSD via cck, it's fine in Tidal.

The iPhone itself isn’t seeing the iDSD. It’s not the app that can’t see it, but iOS

I can try a different cable Monday, but the one I was using is brand new

 

[iFi audio]

I noticed that the videos only show Bit Perfect playback. Are there any restrictions regarding use of filters?

As MQA controls the time- and supersonic frequency domain behaviour of the system all the way to the analogue output, there are no options for filtering or upsampling available, as they would fundamentally act opposite to what MQA is all about, namely a reliable and certified "studio master" result to the analogue outputs.

can an unfolded MQA file with 384Khz be played back with GTO filter plus DSD1024 conversion?

No. In order to be MQA certified, full control over all sampling options rests with the MQA renderer component. Adding additional and optional filtering/upsampling would break any MQA certification.

 

[gordec]

Any way to disable WiFi and only use Ethernet?

 

[audiocraze]

As MQA controls the time- and supersonic frequency domain behaviour of the system all the way to the analogue output, there are no options for filtering or upsampling available, as they would fundamentally act opposite to what MQA is all about, namely a reliable and certified "studio master" result to the analogue outputs.



No. In order to be MQA certified, full control over all sampling options rests with the MQA renderer component. Adding additional and optional filtering/upsampling would break any MQA certification.

OK I can understand now why so many dac companies refuse to implement MQA. It’s very restrictive. Do you know if the FPGA chip is used at all, or if all 8 burr brown dac chips are used or only one? Does it matter what converter is used if MQA creates the same “studio master” analogue signal? How can different DACs sound different?

 

[austinpop]

I've been playing with the 2.0 beta firmware. Functionality wise, there are a few glitches when switching between MQA and non-MQA streams. If you interrupt a Redbook stream to play MQA (or vice versa), you might encounter a burst of static. This can be avoided by pausing first. But these are minor issues, and I expect will be fixed before GA.

To the extent you care about MQA playback, it seems to work just great with Tidal streams, and the few MQA 2L samples in my library. Yes, there are NO options when you playback MQA. No filters. No DSD Remastering. But that isn't iFi's fault - it's MQA-mandated behavior.

What I do like about the Pro iDSD's MQA implementation is that unlike the Micro iDSD Black Label, adding MQA support in the firmware did not reduce the sample rates supported for non-MQA content. The 2.0beta firmware will still support up to 768k PCM and DSD512 inputs.

All in all, 2.0 beta is a very promising update, and hopefully the glitches will be fixed soon.

 

[flyte3333]

Functionality wise, there are a few glitches when switching between MQA and non-MQA streams. If you interrupt a Redbook stream to play MQA (or vice versa), you might encounter a burst of static. This can be avoided by pausing first.

Can you share exactly what causes this for you? Like the exact track (and their sample rate) sequence - so that I can try to reproduce it at my end?

And what is your USB source when you have this static?

Does the static only happen when transitioning from 16/44 to 24/44? And with Roon only? Do you get it with another program, like Audirvana (using the same tracks and sequence)?

I don't get it going from 16/44 to 24/48/88/96 (MQA and non-MQA) for example. I only get the static from from 16/44 to 24/44 (whether MQA or non-MQA 24/44)... and only with Roon and only with a Linux based USB source...

 

[austinpop]

@Em2016

The important thing is you get the static too. I didn’t test it as carefully as you, so hopefully iFi will benefit from your input!

 

[flyte3333]

@Em2016

The important thing is you get the static too. I didn’t test it as carefully as you, so hopefully iFi will benefit from your input!

It would be nice to see if your bug is different... If you can share the above details I (and anyone else) can try to reproduce it...

 

[austinpop]

It would be nice to see if your bug is different... If you can share the above details I (and anyone else) can try to reproduce it...

Hi Sean,

My chain is in my signature: Zenith SE > tX-USBultra > Pro iDSD (over USB).

I think you are correct on all your observations:

1. my endpoint is Linux.
2. the static only happens on Roon, not on LMS
3. it only happens when going from 16 <-> 24 bits (both directions) at 44.1 kHz. I could not make it happen on any other sample rate.
4. Setting the Resync Delay (I tried up to 2000ms) did not help.

This is as far as I have the time to test. I am sure iFi are working on a newer version with fixes.

 

[flyte3333]

Hi Sean,

My chain is in my signature: Zenith SE > tX-USBultra > Pro iDSD (over USB).

I think you are correct on all your observations:

1. my endpoint is Linux.
2. the static only happens on Roon, not on LMS
3. it only happens when going from 16 <-> 24 bits (both directions) at 44.1 kHz. I could not make it happen on any other sample rate.
4. Setting the Resync Delay (I tried up to 2000ms) did not help.

This is as far as I have the time to test. I am sure iFi are working on a newer version with fixes.

Thanks Rajiv.

There has been very recent discussion of this same issue on the Roon forum with other XMOS based USB DACs... especially with newer XMOS interfaces... the Pro iDSD's XMOS interface is definitely one of the newer ones.

Roon CTO's public post and discussion:
https://community.roonlabs.com/t/dac-issues-with-xmos-usb-chipset-and-roon-on-linux/52911/11

You will probably observe that even with Roon, if you have a direct USB connection to your Windows or Mac running the Roon Bridge program, you won't have any issues. You will also probably observe that the SPDIF input (which also supports MQA) won't see any of these issues.

So it seems specific to Roon AND Linux based USB endpoints (and XMOS based USB DACs of course).

Roon has mentioned that this should be fixed at the DAC end (i.e. firmware update).... so I hope @iFi audio can speak with Roon about what's happening or investigate themselves...

I am sure iFi are working on a newer version with fixes.

Only if they were aware before this

They are now aware though

This is why I was asking you for additional details... giving steps to reproduce the issue helps iFi to zoom in on the issue and hopefully a solution...

 

[iFi audio]

Do you know if the FPGA chip is used at all, or if all 8 burr brown dac chips are used or only one? Does it matter what converter is used if MQA creates the same “studio master” analogue signal? How can different DACs sound different?

MQA requires a single pre-defined digital filter response. The MQA renderer portion is tuned by MQA to complement this filter and produce the required response. However, this applies ONLY in order to play MQA content and does not affect any other audio.

In our case the FPGA is active (it always is) and all DACs are used. The choice between Solid State, Tube and Tube+ remains as is.

So MQA only restricts playing MQA content and for reasons that are essential to allow MQA to deliver the state aims of certified "Studio master" to the analogue outputs.

MQA do not in any way restrict any DAC manufacturer from doing whatever they please as far as non-MQA playback goes.

We choose to support MQA because we had a substantial portion of customers requesting MQA both in public here on forums and in private. We are fundamentally "format agnostic" and will support any format with sufficient market support and aim to deliver the best possible sound quality from this format, be it traditional PCM, DSD or now MQA.

 

[iFi audio]

I've been playing with the 2.0 beta firmware. Functionality wise, there are a few glitches when switching between MQA and non-MQA streams.

Thank you for testing V2.0. Please help us resolving issues you encounter by reporting them via our support system to be found here: http://support.ifi-audio.com