Looking for latest & greatest CamillaDSP hardware options, inc non-USB input & output, DSP, DAC, etc.

[jeffme]

Forgive me if I've misunderstood the design brief,

Ha! "Design brief"! : ) Flatttery will get you everywhere.

but it seems to me that Roon driving a fleet of RPi/HifiBerry I2C DAC units running Ropieee gets you everything you've asked for except DSP correction of Airplay / Spotify guests. Ropieee offers the streaming protocols alongside being a Roon endpoint, but can't do the DSP. Admittedly, the hardware is not especially luxe looking and the Hifiberry sinad numbers aren't especially bragworthy, but it works quite nicely.

Chromecast is actually the limiting factor, as we're an Android household. I've looked at Ropiee and used Shairplay, but am hoping to make Pi-based elements the smallest part of the signal path I can, not for quality issues of any sort, but just general management. That said, I'll give it another look / consideration.

Separately, I hadn't seen the Hifiberry SINAD numbers until you prompted me. DAC+ 86 and DAC2 HD here. Sounds like this is arguing for a non-Pi-based DAC, which kind of stinks and drives the price point and space factors higher than I'd like. Hifiberry vs DAC2 thread. To me, this one is a no-brainer, as the prices are too close.

That's basically what I do; the only bit of friction is handing off volume levels between Roon and Shairplay; the underlying Alsa process retains the last volume setting in roon as the top of the scale for Shairplay. So in practice, I stop the music in Roon, bump the zone volume up, quit Roon, and then connect to the Airplay endpoint with iphone volume low, and adjust to taste.

Appreciate this - the whole "what's controlling the volume" is an Achilles' heel for usability.

With regard to clocking the whole system - It doesn't always get the marketing attention, but Roon's RAAT protocol handles network sync between zones quietly and capably. That puts the music rendering endpoints on the end of Cat6 cables (or wifi) rather than running digital or analog audio around the building on dedicated wiring. Each device adjust its digital clocking independently and imperceptibly. I gather there are non-IP standards for passing digital audio over cat6 in the professional studio world, but that's out of scope for residential use.

Finally - Be mindful of the latency for the DSP processing for each room. I'm imagining 4 different DSP correction filters might end up having different lengths / latencies, and that might be tricky to reconcile. I mention it because I've got a bunch of pi/hat stacks scattered about, but my main rig runs CamillaDSP for crossover & correction. I can't group it to other zones in Roon because the Camilla process is 'after' Roon, and so can't be automatically kept in sync. It sounds just delayed enough to be unlistenable. All the other basic realtime DAC devices group together just fine.

From a post filled with good feedback, this may be the most valuable nugget. I hadn't considered the issue of DSP-related processing delays across zones. Were you just comparing non-DSP'd zones to DSP'd zones or across zones with DSP but different processing requirements? If the latter, that would be a big deal. I'm hoping it's mainly a some DSP to no DSP comparison.

Again - many thanks!!

 

[kemmler3D]

This might be way off-target, but if you have more than a few hundred in budget (apparently yes) and a rack to mount things in (also apparently yes), why not use a 1U windows PC and run EQAPO with one of the handy-dandy 8i8o PCIE cards mentioned ITT? You can get an old refurb Dell server for less than $300 and it will run as much DSP as you can possibly find a use for.

 

[AlfaNovember]

I'm hoping it's mainly a some DSP to no DSP comparison.

Correct. Here's the whole system:

- The 'Office' main zone does an @OCA "convolution with inversion" DSP filter in Roon, which streams @44.1 to a CamillaDSP upsampled to 88.2, crossover/volume/time align filter to MOTU M4 to 4 channels of amps. Speakers are DIY actives, no analog xover.
- 'Garage', is a simple no-dsp HifiBerry Amp+ zone. Trad speakers w/ analog xovers. No DSP. Within earshot of Office, the zone-group delay is objectionable. Office is late due to xover latency.
- 'Living Room' is 2ch HiFiBerry Dac, trad/analog, with an convolution/inversion DSP filter in Roon.
- 'Kitchen' is a 2ch HifiBerry Dac, downmixed to mono, no DSP, playing into a Sangean trad/analog table radio. Kitchen and Living Room are an open-plan joined space, and can be grouped seamlessly in Roon.

Roon server runs as a service on a Synology NAS in the garage, the endpoints are Cat5 hardwired, system volume is controlled through Roon. All family devices are Apple, and have the Roon app for UX. Content use is 95% Roon, 5% Airplay.

(Having typed that out, I'm realizing I should probably resample the Office zone to 88.2 in Roon and do the correction DSP at the higher sample rate)

 

[jeffme]

This might be way off-target, but if you have more than a few hundred in budget (apparently yes) and a rack to mount things in (also apparently yes), why not use a 1U windows PC and run EQAPO with one of the handy-dandy 8i8o PCIE cards mentioned ITT? You can get an old refurb Dell server for less than $300 and it will run as much DSP as you can possibly find a use for.

I love the idea of doing DSP for all as many zones as possible in 1 PC. As mentioned, my imagination falls short on how the actual physical connections would work. What did you have in mind? Maybe a USB hub & HiFi man adapters for input? And, then I could use as many USB external sound cards (like the Sound Blaster X4) as needed at 4 output per?

The problem with servers is that they can get loooong & all of this is likely going into a 20 or 24" deep AV rack. Luckily, mini PCs and USB connections are cheap!

 

[jeffme]

(Having typed that out, I'm realizing I should probably resample the Office zone to 88.2 in Roon and do the correction DSP at the higher sample rate)

Ha! Never say it out loud... it always means more work.

Seriously, that's great help & feedback on your setup. I'll need to mull this over & play around with some stuff to see what works best (or not annoyingly out of sync!).

 

[kemmler3D]

I love the idea of doing DSP for all as many zones as possible in 1 PC. As mentioned, my imagination falls short on how the actual physical connections would work. What did you have in mind? Maybe a USB hub & HiFi man adapters for input? And, then I could use as many USB external sound cards (like the Sound Blaster X4) as needed at 4 output per?

The problem with servers is that they can get loooong & all of this is likely going into a 20 or 24" deep AV rack. Luckily, mini PCs and USB connections are cheap!

So I misread @voodooless 's post #3 about the PCI-E card, thinking there was a really cheap 8 in 8 out card. He wrote 2 in, duh.

However, there is an 8i8o focusrite USB interface for not a ton of money, e.g. Focusrite Scarlett 18i8. It even has one optical input so you can get a WiiM Mini for that one.

Physically it would just look like 4x RCA->TRS going into the Focusrite, 4x RCA -> TRS (or TRS -> XLR as the case may be) going to the amp(s), and a USB from the focusrite to the server.

There is some SINAD penalty for not doing it all digital, but realistically it would not be audible in almost any situation.

Also for what it's worth, you do not need a server to run DSP. If we're just talking one FIR per channel pretty much any modern computer can do it, so you can go with a mini-PC or frankly any CPU made in the last 10 years. I just thought a server made sense because of the rack-mounting, but you could put a mini-PC next to all the WiiMs and audio interface in a rack tray / drawer.

Lastly, if you end up with different length filters for each channel, it's pretty straightforward to add delay to 3 of the channels to match the slowest one, I think delays are built into EQAPO, if not you can easily find a VST that will do a delay for X samples so you can line it up.

 

[jeffme]

So I misread @voodooless 's post #3 about the PCI-E card, thinking there was a really cheap 8 in 8 out card. He wrote 2 in, duh.

However, there is an 8i8o focusrite USB interface for not a ton of money, e.g. . It even has one optical input so you can get a WiiM Mini for that one.

Physically it would just look like 4x RCA->TRS going into the Focusrite, 4x RCA -> TRS (or TRS -> XLR as the case may be) going to the amp(s), and a USB from the focusrite to the server.

There is some SINAD penalty for not doing it all digital, but realistically it would not be audible in almost any situation.

Also for what it's worth, you do not need a server to run DSP. If we're just talking one FIR per channel pretty much any modern computer can do it, so you can go with a mini-PC or frankly any CPU made in the last 10 years. I just thought a server made sense because of the rack-mounting, but you could put a mini-PC next to all the WiiMs and audio interface in a rack tray / drawer.

Lastly, if you end up with different length filters for each channel, it's pretty straightforward to add delay to 3 of the channels to match the slowest one, I think delays are built into EQAPO, if not you can easily find a VST that will do a delay for X samples so you can line it up.

Gracias! I was just sitting here realizing that if I gave up the Chromecast requirement, I could probably follow @AlfaNovember's advice & keep everything in USB until the final output, maybe just run a bunch of Rpi Zero 2Ws into the Camilla MiniiPC.

Or, if someone had a usable Moode / Ropiee VM, I could run several on the MiniPC... but... we *do* need Chromecast. Need to revisit that, with the partner...

I like the Scarlett, but not the D -> A -> D path it implies for this application.

 

[melomane13]

because no one have proposed, another solution is:
server, Logitech media server , can stream same or different program to finals points, support spotify, tidal ... can be installed on PC or RP.
players: raspberrypi 0 W 2 with picoreplayer and camilla dsp ( here a script for install https://github.com/JWahle/piCoreCDSP ), usb sound card