Using miniDSP 2 x 4 HD's usb port as output.

[kukocz]

I'm successfully running camilladsp on rpi4 (dietpi) to route audio from DDRC-24 to USB DAC along with minidsp-rs to control minidsp.
I also wanted to use rpi as a streamer (raspotify) but it turned out that sound is either interrupting or completely distorted.

It looks like DDRC-24's USB is not capable to work bi-directional using two different processes on rpi side.
Any ide what could be changed in camilldsp .yml config file to fix the issue?

 

[mdsimon2]

I'm successfully running camilladsp on rpi4 (dietpi) to route audio from DDRC-24 to USB DAC along with minidsp-rs to control minidsp.
I also wanted to use rpi as a streamer (raspotify) but it turned out that sound is either interrupting or completely distorted.

It looks like DDRC-24's USB is not capable to work bi-directional using two different processes on rpi side.
Any ide what could be changed in camilldsp .yml config file to fix the issue?

Maybe try the CamillaDSP thread on DIY Audio? Feels like it would be a bit challenging as you almost want the DDRC-24 to act as an output device in CamillaDSP.

As a bit of a hack solution you could electrically measure the DDRC-24 output after applying Dirac and then recreate that transfer function using a FIR filter which you then apply in CamillaDSP. Not sure if you need the analog / TOSLINK inputs of the DDRC-24 but it would be a way to get Dirac processing with just your USB DAC.

Michael

 

[kukocz]

Maybe try the CamillaDSP thread on DIY Audio? Feels like it would be a bit challenging as you almost want the DDRC-24 to act as an output device in CamillaDSP.

As a bit of a hack solution you could electrically measure the DDRC-24 output after applying Dirac and then recreate that transfer function using a FIR filter which you then apply in CamillaDSP. Not sure if you need the analog / TOSLINK inputs of the DDRC-24 but it would be a way to get Dirac processing with just your USB DAC.

Michael

Thanks,
maybe it's a good place to look for the solution.

To make my usecase crystal clear I'll describe it in more details:

Current scenario:

• Rpi4 with dietpi onboard
• usb connection from rpi to external DAC and DDRC24
• camilladsp is configured in the way that it grabs audio output from DDRC24 and redirecting to external DAC
• it is working like a harm when I use i.e. toslink input in minidsp.

When I configure raspotify on rpi4 and set output device to USB of DDRC-24 the sound is interrupting or it's distorted.

I suspect that there is something with configuration to deal with. Normally, when you connect DDRC-24 to PC you can play music and capture it at the same time (or you can use REW to perform full frequency sweep and capture processed signal - it's nice feature to check correction headroom by the way).

Here's my .yml config:

devices:
  samplerate: 192000
  capture_samplerate: 48000
  chunksize: 1024
  enable_rate_adjust: true
  queuelimit: 1
  capture:
    type: Alsa
    channels: 4
    device: "hw:CARD=DDRC24"
    format: S32LE
  playback:
    type: Alsa
    channels: 2
    device: "hw:CARD=LAQXD1"
    format: S32LE
mixers:
  minidsp2DAC:
    channels:
      in: 4
      out: 2
    mapping:
      - dest: 0
        sources:
          - channel: 0
            gain: 0
            inverted: false
      - dest: 1
        sources:
          - channel: 1
            gain: 0
            inverted: false
pipeline:
  - type: Mixer
    name: minidsp2DAC

 

[RoyB]

Along the same lines of this question.......How do I run a Node2i that is connected to a Gustard X16 digitally through the miniDSP-HD and into my analog inputs of my preamplifier?

 

[kukocz]

Along the same lines of this question.......How do I run a Node2i that is connected to a Gustard X16 digitally through the miniDSP-HD and into my analog inputs of my preamplifier?

Node 2i <=optical=> minidsp HD <=USB=> raspberry pi zero 2/3B/4 with camilladsp <=USB=> Gustard X16 <=RCA/XLR=> preamp

 

[Strobilus]

Great thread, I have received valuable information concerning on how to add a display to my DDRC-24 and using CamillaDSP to route audio from the minidsp to an external DAC. However I have one question which would be great to get input on based on my audio system set up.

As I use my DDRC for 2.1 (3 outputs) and the DAC I'm thinking of using having 2 outputs (RCA/XLR), in the case of routing the audio to an external DAC, will the DDRC still send signal to the analog outputs? In short, the subwoofer would receive the analogue signal (output 3) from the minidsp while my stereo speakers get the signal from the DAC?

I now make an assumption that I can modify the .yml file for camillaDSP so that only the stereo channels form the minidsp (channel 1 & 2) are used by the DAC.

Do you think this is a case that could work? I am planning to test out as soon as I have the time to get my pi in order with CamillaDSP.

Thanks!

 

[mdsimon2]

Great thread, I have received valuable information concerning on how to add a display to my DDRC-24 and using CamillaDSP to route audio from the minidsp to an external DAC. However I have one question which would be great to get input on based on my audio system set up.

As I use my DDRC for 2.1 (3 outputs) and the DAC I'm thinking of using having 2 outputs (RCA/XLR), in the case of routing the audio to an external DAC, will the DDRC still send signal to the analog outputs? In short, the subwoofer would receive the analogue signal (output 3) from the minidsp while my stereo speakers get the signal from the DAC?

I now make an assumption that I can modify the .yml file for camillaDSP so that only the stereo channels form the minidsp (channel 1 & 2) are used by the DAC.

Do you think this is a case that could work? I am planning to test out as soon as I have the time to get my pi in order with CamillaDSP.

Thanks!

Although it should be possible I do not think it is a good idea.

In such a setup you are using two USB DACs with two asynchronous clocks. These DACs will not stay sync'd over time and will result in phase inconsistencies which will result in poor integration between your speakers and subwoofer.

In addition CamillaDSP will add latency compared to the DDRC-24, depending on your CamillaDSP settings you might be able to compensate for this in the DDRC-24, although most CamillaDSP configurations will have at least 30 ms delay minimum and the DDRC-24 only has the ability to implement 30 ms of delay.

Michael