Introducing DSPi | A powerful, user friendly and open source DSP for less than a cup of coffee

[Mike123]

I was setting up my system and had a rather indiscreet question. Is there no 88.2 kHz support because no one needs it? Or is there some problem with it? It would be very convenient to not change all frequencies <=96 kHz and downsample all frequencies >=96 kHz.

I hope to make Linux and RPi users very happy soon. Hint hint!

Wow. Super .

 

[BodeMedia]

I'm having trouble getting audio out of this DAC board.

Data = GPIO 6
BCK = GPIO 14
LRCK = GPIO 15
5v and GND to PSU
MCLK = floating because this board has it's own TeraDak oscillator.

Output is configured to i2s on the correct pins, matrix is setup correctly. I see signal coming in and out of the console, but no audio output.

What am I missing?

 

[BodeMedia]

I'm having trouble getting audio out of this DAC board.

Data = GPIO 6
BCK = GPIO 14
LRCK = GPIO 15
5v and GND to PSU
MCLK = floating because this board has it's own TeraDak oscillator.

Output is configured to i2s on the correct pins, matrix is setup correctly. I see signal coming in and out of the console, but no audio output.

View attachment 555379
View attachment 555380
View attachment 555381

What am I missing?

I think I had a bad board. The second DAC is working. All good so far!

 

[bogdansrb]

DSPi doesn’t pass SPIDIF input through ASRC. Instead it recovers the clocks and then uses them to servo the PIO output dividers; both for SPDIF, I2S and ADAT outputs. All output slots are sample aligned for SPDIF and ADAT (DSPi slave mode) inputs.

So the sample rate and subsequent I2S clocks are synced to SPDIF?

 

[Biblob]

I'm having trouble getting audio out of this DAC board.

Data = GPIO 6
BCK = GPIO 14
LRCK = GPIO 15
5v and GND to PSU
MCLK = floating because this board has it's own TeraDak oscillator.

Output is configured to i2s on the correct pins, matrix is setup correctly. I see signal coming in and out of the console, but no audio output.

View attachment 555379
View attachment 555380
View attachment 555381

What am I missing?

"QC Passed"

 

[Weeb Labs]

So the sample rate and subsequent I2S clocks are synced to SPDIF?

Exactly.

 

[john61ct]

So the sample rate and subsequent I2S clocks are synced to SPDIF?

Or alternatively to ADAT

 

[john61ct]

DSPi doesn’t pass SPIDIF input through ASRC. Instead it recovers the clocks and then uses them to servo the PIO output dividers; both for SPDIF, I2S and ADAT outputs. All output slots are sample aligned for SPDIF and ADAT (DSPi slave mode) inputs.

So just to clarify my limited understanding

I've been trying to research HowTo get BNC Word Clocking integrated with I2S clocking without spending $100's on specialised devices

not just for DSPi use but in general.

However, with multiple DSPi specifically, please confirm

if feeding them ADAT or S/PDIF (TOSlink or Coax)

so long as the source devices are all kept in sync via BNC Word Clock

no need to further worry about clock sync between DSPi units?

Time taken by processing, time of flight delays etc can be handled separately, here I'm just asking about preventing clock drift.

Also, is the answer the same for AES3 input?

If anyone can help at at all with the "big picture" top research project, if it's OT to DSPi specifically, please start a new thread, or post here

DSPi users (and prospects) projects discussions

As requested, to keep the main dev thread less cluttered for their internal more techie topics https://www.audiosciencereview.com/forum/index.php?threads/introducing-dspi-a-powerful-user-friendly-and-open-source-dsp-for-less-than-a-cup-of-coffee.69343 I'm starting this for more user-oriented...

www.audiosciencereview.com

 

[bogdansrb]

DSPi Console does not run on a Windows 10 Virtualbox VM. It doesn't throw any error, it just doesn't run. I've install dotnet framework.

 

[BossBunos]

Exactly.

Would it be a good option to use an lvds ic to send the i2s outpur to a second speaker to split the DACs+amps between 2 speakers?

 

[bogdansrb]

I successfully configured and ran DSPi with an ES9081 DAC. I'm feeding MCLK from a separate crystal. All 8 channels work perfectly.
Ignore the messy soldering and resistors, it's a test board.

 

[Bamboszek]

Very nice. Did you managed to get it done on only two layers?
What LDO are you using?

 

[bogdansrb]

Very nice. Did you managed to get it done on only two layers?
What LDO are you using?

Yes.
I'm using the ES9312 for the main analog rails and NCP163 for the rest.

 

[MCH]

I successfully configured and ran DSPi with an ES9081 DAC. I'm feeding MCLK from a separate crystal. All 8 channels work perfectly.
Ignore the messy soldering and resistors, it's a test board.

Great choice for a budget multichannel DAC!

 

[bogdansrb]

Great choice for a budget multichannel DAC!

Indeed. The integrated line drivers eliminate a lot of circuitry in the analog section.

 

[bogdansrb]

I added a rotary encoder for volume and mute and it works perfectly. However SPDIF doesn't, DSPi doesn't even register any incoming signal. I probed the signal and it's 1VRms, might that be too low?

 

[Weeb Labs]

I added a rotary encoder for volume and mute and it works perfectly. However SPDIF doesn't, DSPi doesn't even register any incoming signal. I probed the signal and it's 1VRms, might that be too low?

I’m glad they’re working! The SPDIF input is 3.3V TTL rather than coaxial, so most users choose a TOSLINK RX for simplicity.

 

[bogdansrb]

I’m glad they’re working! The SPDIF input is 3.3V TTL rather than coaxial, so most users choose a TOSLINK RX for simplicity.

Yeah I only have coaxial for testing. I guess I'll try this circuit.

 

[Jamproject]

Hello,
I (maybe) would like to use it with only one rotary encoder with following functionnality:
- turn to change volume
- push to change source
- long push to turn on/off the system (230V voltage input), by controlling a solid state relay.
For the last, I would need to toggle an output on the pico, but I did not find a way to do it? Is it possible/planned to create random outputs?

 

[bogdansrb]

I haven't found a way to switch sources from a control surface. Maybe it's planned. But you can change volume.
Output toggles would be a nice feature.