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DAC + ADC as input selector for digital source and turntable: a conundrum?

mdsimon2 said:
You should be able to check it with something like REW or Audacity on the RPi. When I first started experimenting with this stuff I used REW to see if I could capture sound from my desired input device. If you can do that you are golden.

Michael
Click to expand...
Just making sure I get it: you're suggesting using RPi #1 to try and capture the table's USB out with CamillaDSP, and routing that out of another one of that RPi's USB ports, and then using RPi #2 to see if it can "capture" the sound from RPi #1's output ? Or do you mean that within RPi #1 I could use stuff like REW to check whether I am successful in capturing the turntable's USB out and routing it out of the Pi ? Sorry I am at ease with tweaking around with the RPi but pretty new to audio stuff.
 
glucenag said:
Just making sure I get it: you're suggesting using RPi #1 to try and capture the table's USB out with CamillaDSP, and routing that out of another one of that RPi's USB ports, and then using RPi #2 to see if it can "capture" the sound from RPi #1's output ? Or do you mean that within RPi #1 I could use stuff like REW to check whether I am successful in capturing the turntable's USB out and routing it out of the Pi ? Sorry I am at ease with tweaking around with the RPi but pretty new to audio stuff.
Click to expand...

In your case I would only use one RPi. For testing purposes I wouldn't even worry about CamillaDSP at this point, that will come later once you have confirmed you have successfully captured a signal from your turntable and want to route it to another DAC (or a RPi digital output HAT).

For now I would install REW on your RPi. REW is rather slow but workable on a RPi3/4, if you have a less powerful RPi we may want to rethink this.

Ideally the turntable shows up as an input device and if you play something on the turntable you are able to see it using on REW's level meters or RTA.

If this works it would also be good to run cat /proc/asound/TURNTABLE/stream0 as it should show you the available input options for the turntable. See below for what this looks like when using a MOTU Ultralite Mk5 audio interface.

Code: 
michael3@raspberrypi3:~$ cat /proc/asound/UltraLitemk5/stream0
MOTU UltraLite-mk5 at usb-0000:01:00.0-1.4, high speed : USB Audio

Playback:
  Status: Running
    Interface = 1
    Altset = 2
    Packet Size = 702
    Momentary freq = 96000 Hz (0xc.0000)
  Interface 1
    Altset 1
    Format: S24_3LE
    Channels: 22
    Endpoint: 0x02 (2 OUT) (ASYNC)
    Rates: 44100, 48000
    Data packet interval: 125 us
    Bits: 24
    Sync Endpoint: 0x83 (3 IN)
    Sync EP Interface: 2
    Sync EP Altset: 1
    Implicit Feedback Mode: Yes
  Interface 1
    Altset 2
    Format: S24_3LE
    Channels: 18
    Endpoint: 0x02 (2 OUT) (ASYNC)
    Rates: 88200, 96000
    Data packet interval: 125 us
    Bits: 24
    Sync Endpoint: 0x83 (3 IN)
    Sync EP Interface: 2
    Sync EP Altset: 2
    Implicit Feedback Mode: Yes
  Interface 1
    Altset 3
    Format: S24_3LE
    Channels: 10
    Endpoint: 0x02 (2 OUT) (ASYNC)
    Rates: 176400, 192000
    Data packet interval: 125 us
    Bits: 24
    Channel map: FL FR FC LFE RL RR FLC FRC RC SL
    Sync Endpoint: 0x83 (3 IN)
    Sync EP Interface: 2
    Sync EP Altset: 3
    Implicit Feedback Mode: Yes

Capture:
  Status: Running
    Interface = 2
    Altset = 2
    Packet Size = 624
    Momentary freq = 96000 Hz (0xc.0000)
  Interface 2
    Altset 1
    Format: S24_3LE
    Channels: 20
    Endpoint: 0x83 (3 IN) (ASYNC)
    Rates: 44100, 48000
    Data packet interval: 125 us
    Bits: 24
  Interface 2
    Altset 2
    Format: S24_3LE
    Channels: 16
    Endpoint: 0x83 (3 IN) (ASYNC)
    Rates: 88200, 96000
    Data packet interval: 125 us
    Bits: 24
  Interface 2
    Altset 3
    Format: S24_3LE
    Channels: 10
    Endpoint: 0x83 (3 IN) (ASYNC)
    Rates: 176400, 192000
    Data packet interval: 125 us
    Bits: 24
    Channel map: FL FR FC LFE RL RR FLC FRC RC SL

Once you have that working we can talk about CamillaDSP configuration.

Michael
 
At the moment I am using a miniDsp SHD as ADC for my turntable and also as DAC. The SHD is even doing the preamp and RIAA correction :)
 
(In case someone
mdsimon2 said:
In your case I would only use one RPi. For testing purposes I wouldn't even worry about CamillaDSP at this point, that will come later once you have confirmed you have successfully captured a signal from your turntable and want to route it to another DAC (or a RPi digital output HAT).

For now I would install REW on your RPi. REW is rather slow but workable on a RPi3/4, if you have a less powerful RPi we may want to rethink this.

Ideally the turntable shows up as an input device and if you play something on the turntable you are able to see it using on REW's level meters or RTA.

If this works it would also be good to run cat /proc/asound/TURNTABLE/stream0 as it should show you the available input options for the turntable. See below for what this looks like when using a MOTU Ultralite Mk5 audio interface.

Code: 
michael3@raspberrypi3:~$ cat /proc/asound/UltraLitemk5/stream0
MOTU UltraLite-mk5 at usb-0000:01:00.0-1.4, high speed : USB Audio

Playback:
  Status: Running
    Interface = 1
    Altset = 2
    Packet Size = 702
    Momentary freq = 96000 Hz (0xc.0000)
  Interface 1
    Altset 1
    Format: S24_3LE
    Channels: 22
    Endpoint: 0x02 (2 OUT) (ASYNC)
    Rates: 44100, 48000
    Data packet interval: 125 us
    Bits: 24
    Sync Endpoint: 0x83 (3 IN)
    Sync EP Interface: 2
    Sync EP Altset: 1
    Implicit Feedback Mode: Yes
  Interface 1
    Altset 2
    Format: S24_3LE
    Channels: 18
    Endpoint: 0x02 (2 OUT) (ASYNC)
    Rates: 88200, 96000
    Data packet interval: 125 us
    Bits: 24
    Sync Endpoint: 0x83 (3 IN)
    Sync EP Interface: 2
    Sync EP Altset: 2
    Implicit Feedback Mode: Yes
  Interface 1
    Altset 3
    Format: S24_3LE
    Channels: 10
    Endpoint: 0x02 (2 OUT) (ASYNC)
    Rates: 176400, 192000
    Data packet interval: 125 us
    Bits: 24
    Channel map: FL FR FC LFE RL RR FLC FRC RC SL
    Sync Endpoint: 0x83 (3 IN)
    Sync EP Interface: 2
    Sync EP Altset: 3
    Implicit Feedback Mode: Yes

Capture:
  Status: Running
    Interface = 2
    Altset = 2
    Packet Size = 624
    Momentary freq = 96000 Hz (0xc.0000)
  Interface 2
    Altset 1
    Format: S24_3LE
    Channels: 20
    Endpoint: 0x83 (3 IN) (ASYNC)
    Rates: 44100, 48000
    Data packet interval: 125 us
    Bits: 24
  Interface 2
    Altset 2
    Format: S24_3LE
    Channels: 16
    Endpoint: 0x83 (3 IN) (ASYNC)
    Rates: 88200, 96000
    Data packet interval: 125 us
    Bits: 24
  Interface 2
    Altset 3
    Format: S24_3LE
    Channels: 10
    Endpoint: 0x83 (3 IN) (ASYNC)
    Rates: 176400, 192000
    Data packet interval: 125 us
    Bits: 24
    Channel map: FL FR FC LFE RL RR FLC FRC RC SL

Once you have that working we can talk about CamillaDSP configuration.

Michael
Click to expand...

Nice. Gotcha. May take me a while to come back to this because of me going on holiday soon but I have an Rpi4 so I will definitely try this. Cheers!
 
MarcosCh said:
Hi! I am very interested on a solution like this! I understood that the only way to transmit via wifi was sonos or darkice internet radio. Can you provide more details or provide a link or something? I would be very grateful, have been looking for something like this for months!!
Click to expand...

See link below for the basic configuration.

https://www.hifiberry.com/docs/software/integrate-analoge-audio-devices-into-your-multi-room-system/

I remember it being a bit of pain to setup (would only work at certainly sample rates / bit depths) but I think that may have been related to specific kernel issues at the time. For reference see below for my current WaveInput custom-convert.conf (located in /var/lib/squeezeboxserver/cache/InstalledPlugins/Plugins/WaveInput).

Code: 
#
# wavin
#
wavin pcm * *
        # R
        [arecord] -d0 -c2 -f S16_LE -r 48000 -twav -D $FILE$
wavin mp3 * *
        # RB:{BITRATE=-B %B}
        [arecord] -d0 -c2 -f S16_LE -r 48000 -twav -D $FILE$ | [lame] --silent -q $QUALITY$ $BITRATE$ - -
wavin flc * *
        # R
        [arecord] -d0 -c2 -f S16_LE -r 48000 -twav -D $FILE$ | [sox] -q -t wav - -t flac -C 4 -

I capture at 16 bit / 48 kHz as this should be more than good info for vinyl and file size grows significantly for higher bit depths / sample rates, even if using FLAC. I also found that the RPi 3B+ built in wifi was not that stable but once I switched to a TP Link AC600 on both sending and receiving ends it worked perfectly.

The only other thing to note is that there is a several second delay that is introduced (especially when using FLAC, I think mp3 may have had less delay but I don't use it and do not remember).

Michael
 
  • Like
Reactions: MCH
BTW, just to have all my options, does anyone have an informed opinion on the adc in the matrix audio mini i 3?
 
mdsimon2 said:
See link below for the basic configuration.

https://www.hifiberry.com/docs/software/integrate-analoge-audio-devices-into-your-multi-room-system/

I remember it being a bit of pain to setup (would only work at certainly sample rates / bit depths) but I think that may have been related to specific kernel issues at the time. For reference see below for my current WaveInput custom-convert.conf (located in /var/lib/squeezeboxserver/cache/InstalledPlugins/Plugins/WaveInput).

Code: 
#
# wavin
#
wavin pcm * *
        # R
        [arecord] -d0 -c2 -f S16_LE -r 48000 -twav -D $FILE$
wavin mp3 * *
        # RB:{BITRATE=-B %B}
        [arecord] -d0 -c2 -f S16_LE -r 48000 -twav -D $FILE$ | [lame] --silent -q $QUALITY$ $BITRATE$ - -
wavin flc * *
        # R
        [arecord] -d0 -c2 -f S16_LE -r 48000 -twav -D $FILE$ | [sox] -q -t wav - -t flac -C 4 -

I capture at 16 bit / 48 kHz as this should be more than good info for vinyl and file size grows significantly for higher bit depths / sample rates, even if using FLAC. I also found that the RPi 3B+ built in wifi was not that stable but once I switched to a TP Link AC600 on both sending and receiving ends it worked perfectly.

The only other thing to note is that there is a several second delay that is introduced (especially when using FLAC, I think mp3 may have had less delay but I don't use it and do not remember).

Michael
Click to expand...

Thank you very much Michael, will give it a try. Latency won't be an issue for me as i am considering this for: 1. wifi transmission of analog (turntable) signal and 2. Eq flac stored in a NAS and transmit to an integrated renderer/DAC/amplifier that doesn't allow eq.
Let's see if i manage to make work at least one of the two.
Thanks!
 
glucenag said:
BTW, just to have all my options, does anyone have an informed opinion on the adc in the matrix audio mini i 3?
Click to expand...
Can't help you with that, but another option for you (and way cheaper and simpler) could be just an rca Y connector or switch at the input of your power amp? - note that this is a question, maybe someone can advice if this could damage your signal or devices...
 
MarcosCh said:
Can't help you with that, but another option for you (and way cheaper and simpler) could be just an rca Y connector or switch at the input of your power amp? - note that this is a question, maybe someone can advice if this could damage your signal or devices...
Click to expand...

You mean wiring the line-level output of the turntable directly into the Power amp? I don't think that's a good idea, among other things because ... no volume control ? :)
 
  • Like
Reactions: MCH
Would you dare contradicting Keith?
Screenshot_20210802-150649_Google.jpg
 
mdsimon2 said:
In your case I would only use one RPi. For testing purposes I wouldn't even worry about CamillaDSP at this point, that will come later once you have confirmed you have successfully captured a signal from your turntable and want to route it to another DAC (or a RPi digital output HAT).

For now I would install REW on your RPi. REW is rather slow but workable on a RPi3/4, if you have a less powerful RPi we may want to rethink this.

Ideally the turntable shows up as an input device and if you play something on the turntable you are able to see it using on REW's level meters or RTA.

If this works it would also be good to run cat /proc/asound/TURNTABLE/stream0 as it should show you the available input options for the turntable. See below for what this looks like when using a MOTU Ultralite Mk5 audio interface.

Code: 
michael3@raspberrypi3:~$ cat /proc/asound/UltraLitemk5/stream0
MOTU UltraLite-mk5 at usb-0000:01:00.0-1.4, high speed : USB Audio

Playback:
  Status: Running
    Interface = 1
    Altset = 2
    Packet Size = 702
    Momentary freq = 96000 Hz (0xc.0000)
  Interface 1
    Altset 1
    Format: S24_3LE
    Channels: 22
    Endpoint: 0x02 (2 OUT) (ASYNC)
    Rates: 44100, 48000
    Data packet interval: 125 us
    Bits: 24
    Sync Endpoint: 0x83 (3 IN)
    Sync EP Interface: 2
    Sync EP Altset: 1
    Implicit Feedback Mode: Yes
  Interface 1
    Altset 2
    Format: S24_3LE
    Channels: 18
    Endpoint: 0x02 (2 OUT) (ASYNC)
    Rates: 88200, 96000
    Data packet interval: 125 us
    Bits: 24
    Sync Endpoint: 0x83 (3 IN)
    Sync EP Interface: 2
    Sync EP Altset: 2
    Implicit Feedback Mode: Yes
  Interface 1
    Altset 3
    Format: S24_3LE
    Channels: 10
    Endpoint: 0x02 (2 OUT) (ASYNC)
    Rates: 176400, 192000
    Data packet interval: 125 us
    Bits: 24
    Channel map: FL FR FC LFE RL RR FLC FRC RC SL
    Sync Endpoint: 0x83 (3 IN)
    Sync EP Interface: 2
    Sync EP Altset: 3
    Implicit Feedback Mode: Yes

Capture:
  Status: Running
    Interface = 2
    Altset = 2
    Packet Size = 624
    Momentary freq = 96000 Hz (0xc.0000)
  Interface 2
    Altset 1
    Format: S24_3LE
    Channels: 20
    Endpoint: 0x83 (3 IN) (ASYNC)
    Rates: 44100, 48000
    Data packet interval: 125 us
    Bits: 24
  Interface 2
    Altset 2
    Format: S24_3LE
    Channels: 16
    Endpoint: 0x83 (3 IN) (ASYNC)
    Rates: 88200, 96000
    Data packet interval: 125 us
    Bits: 24
  Interface 2
    Altset 3
    Format: S24_3LE
    Channels: 10
    Endpoint: 0x83 (3 IN) (ASYNC)
    Rates: 176400, 192000
    Data packet interval: 125 us
    Bits: 24
    Channel map: FL FR FC LFE RL RR FLC FRC RC SL

Once you have that working we can talk about CamillaDSP configuration.

Michael
Click to expand...

So it does not work. At least not out of the box. For starters, plugging the turntable in the RPi3 does not alter lsusb's output, so I think the Pi isn't even seeing the turntable - let alone REW in the "input device" scroll down menu from the preferences menu.

I've googled "sony ps-hx500 linux" and related stuff but to no avail, and the drivers from Sony's website are for Windows or Mac only. If anyone has any idea, please comment!
 
glucenag said:
So it does not work. At least not out of the box. For starters, plugging the turntable in the RPi3 does not alter lsusb's output, so I think the Pi isn't even seeing the turntable - let alone REW in the "input device" scroll down menu from the preferences menu.

I've googled "sony ps-hx500 linux" and related stuff but to no avail, and the drivers from Sony's website are for Windows or Mac only. If anyone has any idea, please comment!
Click to expand...

Ahh, that is too bad, would have been an elegant solution if this worked. You can also run CamillaDSP on Windows or Mac but I have not done it and obviously the hardware is more expensive and/or bulkier.

Michael
 
mdsimon2 said:
Ahh, that is too bad, would have been an elegant solution if this worked. You can also run CamillaDSP on Windows or Mac but I have not done it and obviously the hardware is more expensive and/or bulkier.

Michael
Click to expand...

Yeah, I considered that, but man do I hate Windows / Mac. And of course, like you say, I am going to need more than a RPi for that. I actually do have a spare PC tower from 10 years ago that can easily run Windows, but it's not like I would want to fit that in between my turntable and my DAC (also, it has fans, makes noises, so the only nice way would be to somehow put this away with long USB cables in and out ... and that just does not seem too realistic nor elegant to me).

SO I guess this poor choice of USB turntable leaves me with your other option, of using some ADC, and you suggested some which are not crazy expensive and which seem to be of decent quality. The thing is, as I understand it, those will also need some RPi in the middle (with better chances of it working as a master, this time). In the end these RPis are cheap but not for free, and if I need at least a 3/4 to make sure it does its job smoothly, I'm looking at adding 50 euros on top of the ADC thing. Gotta say it makes me wonder if I would not want to just go the easy route and go for the Matrix Audio Mini i (Pro) 3, and plugging in the turntable's line output and call it a day. Or, for the same price basically, I can go for one of my DACs that I like without RCA in and purchase the puffin parks audio, which costs about the difference between one of these DACs and the Matrix.

I have to admit I am a bit lost. If people have inputs on the quality of the ADC in the Matrix Audio Mini i 3, I'd take them!

Cheers.
 
Spec'd ADC performance on the Matrix is not exceptional but definitely competent (~90 dB SINAD), based on measurements of the DAC seems like a far assumption they will meet their specs.

Looking back through this thread I think the suggestions by @MarcosCh on post 12 are quite good. Spec'd performance on the AD24QS-FS is really good (better than the Matrix) but it is a DIY kit requiring assembly. As a budget option the Swisstronics Converter looks OK (better than the really cheap ADCs but not great). Both of these options have conventional digital outputs which is what you are looking for.

Michael
 
Ah, I missed the Swisstronics. Looks like that's something I could go for. The DIY route seemed appealing but you end up spending 200 bucks (casing included) to end up with something that I think has only a small chance of sounding better to me than this OK-checked Swisstronics.

One concern I have is that clipping happens at 1.5Vrms for the Swisstronics. I could not find the voltage information for the line level output of the turntable, nor am I able to measure it since my multimeter's AC settings are all really high (meant for wall plugs, etc.). Anyone has a guess as to what the voltage level could be there?
 
mdsimon2 said:
Spec sheet has the line out voltage at 190 mV so you should be OK.

Swisstronics will definitely be a lot noiser (+35 dB, 70X more noise) but it also seems likely you will be limited by the preamp in the turntable and vinyl of course is not a low noise source.

Michael
Click to expand...

Ah, well you are better than me at finding spec sheets then! Thanks. Yeah the noise seems less than optimal on the Swisstronics, for sure. But it's like you say: Vinyl is far from a noise-free source (and in my case it's old vinyls, too...) and of course who's to say the turntable's phono stage is absolutely perfect? For 50 bucks I am willing to give this a try and if I somehow feel it is ruining the experience for me then I'll just bite on it until I can afford a better ADC (or a phono stage with digital out altogether, like the Puffin). At least I won't have limited myself to DACs with RCA inputs (whose ADCs also could have ended up being disappointing). Honestly, right now the turntable is hooked to an old integrated amp (phono in) (a Pioneer from 20 years back that was far from top of the line back then) together with a pair of entry-level bookshelf speakers, so I wonder if the rest of the modifications I am going to do to my setup aren't going to end up compensating for the turntabl's built-in phono stage + average Swisstronic combo. I guess I'll find out.

On a side note, I find it slightly weird that there isn't a (more) decent ADC with coax or toslink output selling for something like 200 bucks, or a phono stage like the Puffin with digital out for maybe a bit more (the Puffin does that but it's 400 bucks and you need to ask for a modification implementing the digital out). But I don't know the market that well in that regard so that's that.
 
Indeed there aren't many cheap ADC, probably for a reason, as nobody seems to need/care about it
 
Thanks jackpine, good to know. Seems that it was even reviewed here
 
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