dCS Network Firmware [398] release announcement

[miguelito (Miguel Barrio)]

Decoder and Renderer: Roon does the MQA core decoding process, applies DSP, re-attaches the MQA signaling information , and sends that stream to the Bridge. This allows the downstream DAC to perform the MQA rendering stage.

Interesting, but why would you not always reattach the MQA rendering bits?

[Roony]

I have tested it one more time.
It has nothing to do with the format of the album, Tidal or not.
The click occurs when a track plays a few seconds, and then I quickly click another track.
It happens 1 of 20 times, and the click is different from strength.
Sometimes so loud that I feared for my speakers.
Now I first put down the the volume before clicking on another track.
That can not be the intention.
For a long time I had an Sonore ultrarendu on the dCS because of this issue.
Now it’s back again…

[AMP (Andrew P)]

Interesting, but why would you not always reattach the MQA rendering bits?

[AMP (Andrew P)]

It has nothing to do with the format of the album, Tidal or not.
The click occurs when a track plays a few seconds, and then I quickly click another track.
It happens 1 of 20 times, and the click is different from strength.

OK, I’ve tried this using a 16/44.1 album and have been sitting here skipping tracks within the first 1 - 2 seconds of audio starting. I’ve skipped over 200 times at this point and haven’t had an issue.

I’ll need some more information so that I can try to replicate this:

1. Does this only happen when changing formats / sample rates (e.g. 16/44.1 to 24/96) or does it happen within tracks of the same album?

2. What is a rate / format for which you know it happened.

3. Is it only with PCM or is it all formats? Have you noticed it more with or without MQA tracks (if you play them)?

4. What amp / preamp do you use? Do you use the volume control in your Rossini?

5. Are you using any of Roon’s DSP functions?

6. What are the settings on your Rossini:

   • Upsampling (DXD / DSD)
   • Output voltage
   • Is the DAC’s buffer on or off?
   • What filter are you using (these are sample rate dependent so please provide the filter for the rate of a track where you know you’ve heard the noise).
   • If you’re using DSD upsampling or have heard it with DSD which DSD filter are you using?
   • If you use the Rossini’s volume control what level is it typically at for normal listening?
   • Do you use an external word clock?

Please provide this info and I’ll try again to replicate.

[AMP (Andrew P)]

The Amber Rubarth DSD128 album has a small pop (on the right channel in my system) on every song transition. Odd. Maybe it was there before and never paid attention.

Added a 100ms sync delay (maybe between tracks it went back to PCM?) but no difference in behavior.

Clicks with DSD are very common and it has to do with taking the original “Album” and slicing it into tracks. DSD has a natural DC offset and if tracks aren’t cut on exactly a zero crossing then the latent offset manifests as a pop. It’s common to get it in one channel and not the other as it’s hard to find a spot where both tracks are at zero.

As for the Roon PCM upsampling case that’s a mystery. It’s one continuous stream and there’s never any kind of changeover either from the DAC’s perspective or the endpoint’s perspective. If you can find a Tidal album that exhibits the behavior please let me know.

I did my tests setup exactly as you describe (Rossini on all defaults and Roon’s upsampling set to Max PCM power of 2) and I can’t get it to glitch.

[Roony]

Does this only happen when changing formats?
No
Sample rates (e.g. 16/44.1 to 24/96)?
No, all kind of formats and Tidal MQA, DSD DXD enz
Or does it happen within tracks of the same album?
No, the same or others

What amp / preamp do you use?
- dCS Rossini DAC with Rossini Clock
- Pass Labs 250.5 power amplifier
- KEF Blade loudspeakers
- All Shunyata cables and filter.
- (LG oled TV and Hama DT100BT Digital tuner)
- Roon: SonicTransporter with 4TB SSD (extern)

Do you use the volume control in your Rossini?
- Yes

Do you using any of Roon’s DSP functions?
- No

What are the settings on your Rossini:
- Upsampling DXD
- Output voltage 6V
**- Buffer off (with buffer on my TV sound is not sync) **
- Filter 1
- Volume control level: 30 - 40

I worked for 22 years in a hifi shop and did sell dCS in the beginning off dCS.
So I know all about hifi and the problems.
I think this is a problem of the network card / firmware.
dCS changed it and the problem is back.

Maybe I can make a recording of it…I will try.

[AMP (Andrew P)]

@Roony, I’ll test using these settings and see if I can generate the same behavior.

- Output voltage 6V
- Buffer off (with buffer on my TV sound is not sync)
- Filter 1
- Volume control level: 30 - 40

One thing I will say here is that this combination of output voltage and volume setting is not recommended. If you need to remove 30 - 40 dB of gain to get to a typical listening level then the output voltage is too high. Problems can arise here if there’s any sort of a glitch after the volume control as that has the potential to be at full scale. If you have to set the volume level down that much then there’s a potential for a noise that’s going to be really LOUD. This is especially true if you’re running without the buffer.

I think this is a problem of the network card / firmware.
dCS changed it and the problem is back.

I have no doubt that you’re experiencing this issue, but until we can reproduce it there’s no way of telling where the actual problem lies. I’ll work on trying to replicate the issue, but if you’re uncomfortable with what this version is doing then I’m happy to provide the instructions on how to roll it back. It’s a simple-enough process, just let me know.

There will be a new version of the network firmware coming out in the December timeframe so if we can get to the root of the problem then we can make sure it’s fixed.

[Roony]

Surprise!
I set the volume setting to 2V and I did not hear a click anymore.
I just skipped that piece in the manual. I thought very arrogant, I know that, ha ha.
Let’s hope it stays that way.
By the way, I have not listened extensively yet, but I hear also a change in the sound, it sounds a bit softer, but whether that is more realistic? Time will tell.
I am very satisfied with the quality of the sound. Especially since I have the KEF Blades. Chicken skin!!
Many thanks Andrew!!

[miguelito (Miguel Barrio)]

Clicks with DSD are very common and it has to do with taking the original “Album” and slicing it into tracks. DSD has a natural DC offset and if tracks aren’t cut on exactly a zero crossing then the latent offset manifests as a pop. It’s common to get it in one channel and not the other as it’s hard to find a spot where both tracks are at zero.

Thx @AMP. I will keep an eye for PCM showing a pop between tracks.

[jie_zhang]

Since my ROSSINI PLAYER upgraded v398, I can’t play DSD256 in ROON. Prior to this, ROON will automatically convert DSD256 to PCM (32/384), which can play smoothly; But now , ROON will automatically convert DSD256 to DSD128, only 2 seconds of sound, then stop, but found the progress bar Continue on the move. What is the reason for this, thank you!

[miguelito (Miguel Barrio)]

I would suggest you reset the DAC info in the audio setup in Roon. I have no such issues.

[Roony]

DSD128 is the max for the Rossini?

[miguelito (Miguel Barrio)]

Yes. Clearly stated in the specs.

[Roony]

Just played a 256 file. No problem here. I think it ia a network problem. Also try to reboot de core.

[miguelito (Miguel Barrio)]

Roon should be downsampling to DSD128. If you click on the audio path you should see that.