Hey guys,
I have the boards, and I am checking them out right now. 🙂
BTW Brian and I have been looking at the prototype and hit on something which will improve Botic - and lots of other modules 🙂 I don't want to let the cat out of the bag just yet - but very soon.
I am feeling much less work pressure lately and will be back into the swing of enjoying this great hobby of mine.
Cheers!
Russ
I have the boards, and I am checking them out right now. 🙂
BTW Brian and I have been looking at the prototype and hit on something which will improve Botic - and lots of other modules 🙂 I don't want to let the cat out of the bag just yet - but very soon.
I am feeling much less work pressure lately and will be back into the swing of enjoying this great hobby of mine.
Cheers!
Russ
Real hit would be to pack an ES9018K2M on the board, right? BTW Botic should be pronounced 'botitch' - I know for sure as I grew up there and went skating there in winter... ;-)
That would increase the cost, complexity and size of the board.
Using a modular aproach allows each person to build a system to their needs and preferences.
It allows for use with other dacs offered by TPA and other companies.
I for exemple won't need usb or spdif inputs, so I'll probably build a BBB/botic input only dac.
Remarks to the cape with ES9018K2M...
- cannot be "open hardware" because of NDA required to sign with ESS
- just one clock for DAC is enough, because it could be able to generate BCLK/LRCK for BBB (not verified yet)
- cannot be "open hardware" because of NDA required to sign with ESS
- just one clock for DAC is enough, because it could be able to generate BCLK/LRCK for BBB (not verified yet)
With only the time to skim this thread (so apologies if this has been mentioned) I'm curious if the anticipated botic might interface multiple DACs from one BBB. ...with the idea of running simple DSP filters for crossovers, etc.
francolargo: yes, 4 I2S stereo channels will be available.
So one can use either 4 DACs or for example one 8 channel DAC - this is the scenario I'm using for driver tests (with ES9018).
So one can use either 4 DACs or for example one 8 channel DAC - this is the scenario I'm using for driver tests (with ES9018).
Thanks Miero! For me, two I2S stereo channels will be sufficient. 🙂 A quick search suggests that implementing useful audio DSP functions on BBB may require a bit of development. However, the persistence of this group has never failed to impress!
Best,
Frank
That is something that would interest me also but agree its a lot of work and way beyond myself.
So my current plan is to take SPDIF off the Botic cape and feed a miniSHARC which in turn feeds a pair of DACs via I2S. Much cleaner than my current MiniDSP solution.
This is in my interest also (but with 8ch crossover). I read somewhere over at the Volumio forum that some managed to run BruteFIR and/or Folve on their units. This might be a possible way to go...
Best regards,
Mattias
SW crossover is not difficult to set-up, an ecasound tool will do the trick: Digital Crossover/EQ with Open-Source Software: HOWTO | Richard's Stuff
Looks like this is IIR only, a convolution engine for FIR filters (like Folve - https://github.com/hzeller/folve) would be even better! [emoji2]
I checked there and one report (with a Rpi) claimed that BruteFIR distorted badly but Folve worked well, and a post on linuxaudio.org claimed Folve includes high and low-pass filters. Certainly, Ecasound offers lots of processing options. For my low/mid XO point - the one I really need - I haven't heard a difference between FIR and IIR. In either case, though, timing adjustments are critical. I will be following this project with great interest.
Frank
Some news!
The boards I created were fine - but I will be making new/better ones. 🙂
I learned a few things from this build.
I need to separate out core concerns from eachother
1) BBB interface and botic features with Isolation I2C and Audio (PCM/DSD) signals with correct power sequencing etc (so no inputs are driven until power good).
2) Re-clocking/Clock generation.
So I am just about to order 4 prototype boards
1) Hermes-BBB which supports Botic application
2) Cronus - Clock generator with reclocking for 8 channels of PCM and 4 channels of DSD it also has a local 3.3V supply. Hermes plugs into Cronus and is powered on the clean side by it. Cronus can use direct soldered clocks or you can plug in a socket and use Rhea clock modules (see below)
3) Rhea - Pluggable Clock adapter which can be used with Cronus. These modules allow you to experiment with various clock strategies/frequencies. Or just to try different clocks.
4) Hermes-Amanero isolator which allows you to use the amanero USB module with the Cronus where the Cronus supplies the master clock. This module isolates and exposes all the Amanero signals so you can use it with just about any DAC.
The great thing is I can now use the Cronus module with lots of sources - not just BBB. I will just create a Hermes board for each source.
I will have more information shortly. 🙂
The boards I created were fine - but I will be making new/better ones. 🙂
I learned a few things from this build.
I need to separate out core concerns from eachother
1) BBB interface and botic features with Isolation I2C and Audio (PCM/DSD) signals with correct power sequencing etc (so no inputs are driven until power good).
2) Re-clocking/Clock generation.
So I am just about to order 4 prototype boards
1) Hermes-BBB which supports Botic application
2) Cronus - Clock generator with reclocking for 8 channels of PCM and 4 channels of DSD it also has a local 3.3V supply. Hermes plugs into Cronus and is powered on the clean side by it. Cronus can use direct soldered clocks or you can plug in a socket and use Rhea clock modules (see below)
3) Rhea - Pluggable Clock adapter which can be used with Cronus. These modules allow you to experiment with various clock strategies/frequencies. Or just to try different clocks.
4) Hermes-Amanero isolator which allows you to use the amanero USB module with the Cronus where the Cronus supplies the master clock. This module isolates and exposes all the Amanero signals so you can use it with just about any DAC.
The great thing is I can now use the Cronus module with lots of sources - not just BBB. I will just create a Hermes board for each source.
I will have more information shortly. 🙂
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