I am thinking about a full DAC here not just streamer. I should be able to receive input from tvs, consoles, avr etc
I don't see how that answers the question. None of the things you mention have ADAT output..I am thinking about a full DAC here not just streamer. I should be able to receive input from tvs, consoles, avr etc
Eh, no, it’s not going to be that easy. It’s also a matter of how fast you can access the pins, how well you can control the timings, etc..@voodooless
What do you mean "toggle"? Is there a need to toggle the pins? I thought once the system boots up they get by prior configuration assigned to a "channel" with clock and sample size and then it's continously transmitted over a low level written I2S interfacing code compiled in c++ or even Python.
If I read right the GPIO pins of the Pi have a clock of about 30 Mhz which is far beyond what audio needs. Then there will be each a shared pin for sample size, clock sync and channel select to keep everything aligned. So I can't think of any problems there as long as the code is error free.Eh, no, it’s not going to be that easy. It’s also a matter of how fast you can access the pins, how well you can control the timings, etc..
That is in a loop toggling only one of the IOs. This doesn’t tell you how fast you can actually an IO in practical applications, let alone a multitude of them.If I read right the GPIO pins of the Pi have a clock of about 30 Mhz which is far beyond what audio needs.
I won’t stop you@voodooless
Voodoo pleaaase just let me try it, even if I burn myself.
I don’t need to cut your finger off to know that it will hurtIt's like you don't want this to be tested .
Don’t buy ICs. Buy an analyzer so you can verify performance of the IOS before you proceed to do anything.But I would be glad for a list of things I should confirm before buying the ICs on a hunch (while this will be probably unavoidable, buying stuff that doesn't work later on and I have to order something else).
But I double and triple checked with GPT4 that most of my ideas are feasible and will work out.
@tinnitus
I didn't want to open a whole different thread because it's too similar. You could use the Raspi even as a streamer because it has enough processing power and RAM. Even WLAN/Ethernet.
@voodooless
Those devices have all optical output, some with two and some with more channels. But oohhh I noticed my confusion now. I keep calling multichannel TOSLINK "ADAT". Looking for Toslink multichannel ICs there are plenty of devices to interface this over I2S through GPIO pins.
We made a moderate progress.
Edit2:
Okay let me summarize where I want to go:
- I want a true high quality multi channel DSP/Streamer/DAC (even it the SINAD is slightly less then top end stereo DACs)
- I want it to be modular and customizable through software updates of the micro controller and the ICs to be replaceble - only Pin calbes and clamp connections, no solder
- processing of 8 inputs over optical and USB and up to balanced outputs
What causes the most headache is how to physically interface the ESS9038 since the package is meant to be soldered. There are breakout bords but it's still not DIY friendly.
For starters it's "enough" if the bare bone device can be programmed and configured over SSH, Web-UI and/or HDMI out. If the core concept works, adding a screen, knobs and a menu interface should be feasable too. But it begs the question if a PI-board is still enough or even the best solution.
Edit3:
This thing could work!
View attachment 280211
Considering the raw parts I have in mind so far the price tag of the whole project without case and OLED screen ranges about 250-300 €, from a pessmist perspective even.
Edit4: (last edit I pinky swear)
I took a look at multiple dedicated ICs like an XMOS USB Interface but those would need additional circuitry for DSP, Streamer, etc... The PI board seems like the best solution no matter how I look at it. Each GPIO pin has a clock of about 30 Mhz and a clock drift of 0,001 % worst case(!). Jitter should never be an issue there.
(I lied)Edit5:
I just remembered some of the Pin outs of the Pi board have 3,3V and 5,0V which is just PERFECT and makes the DC-DC stuff also unneccsary for the most part. Nice!
On first glance your guide looks great! This might be it!Why fuss around with I2S when there are so many multichannel USB DACs that work well with the Pi? The approach described in my signature meets all of your requirements with completely off the shelf equipment including a remote control, case and display. Why complicate it more?
Michael
On first glance your guide looks great! This might be it!
I skimmed over it but basically I can follow your guide with a Motu Mk5 and have a plug and play device for multiple inputs, outputs, DSP and even optical in?
I did! But I send the UltraLite back because it didn't have multichannel, it just had multiple stereo outs (at least in Windows) which was pretty useless for movies and gaming.That’s what I said in the first place: get a multichannel USB interface
Okay what it boils down to is that I want ditch my AVR and have one single core audio device that can be connected to a PC over USB and as an optical input for all other home devices like TV or consoles.
Whenever I wanted to use multichannel I had so use HDMI, eARC and the Denon X3700 while also turning a knob in my passive XLR switch to change the power amp routing.
This all could be omitted if I had one core device where I just need to change the input source (usb/optical) and then the same FIR processing is applied regardless of the input device and clock. So no matter what I use as input, the room calibration would apply and I have the same high quality output (UltraLite Mk5 for example).