Multichannel audio on a Pi will get a whole lot easier and cheaper!

[Frunse]

Ok changed the Plan without FIFO and Clock from First ASRC, MCLK OUT to MCLK IN next ASRC without XO and so on.
Will test what happen to that LCRK and BCK Lines if i split it to 4 ASRC Boards if i put them close one over the next with this Conectors 2,54mm (Stacking them Up).

Robert

 

[phofman]

Of course my previous post should have been "Do as you want", not "as I want"

Ok I see, need to sell it again
Damm I was to fast and to fourius to buying it .....

Happens to me all the time, our house IS full of stuff not used in the end

 

[somebodyelse]

Happens to me all the time, our house IS full of stuff not used in the end

I resemble that remark!

 

[Frunse]

Of course my previous post should have been "Do as you want", not "as I want"


Happens to me all the time, our house IS full of stuff not used in the end

Its still an nice piece of Hardware, may be i can do an other Project with it. Need to think aboout.

Have still lots to do other Stuff like my CNC Converting to 380Volt from 230V and Cutting all the Enclousures for the Amps Installing Toolchangespindel and so on.

Ian's Stuff get sendet back to Audiophonics with RMA not an Big Deal very nice Shop.

Robert

 

[charlielaub]

Resampling is no longer a horror show to be avoided at all costs. Running everything at a fixed resampling rate can make life a lot easier...

 

[Frunse]

Hello Experts this crazy german Guy has an stupid idea and need Advise!

If i use 2 RPI 5 with same Software (Camilla DSP) and spread my 4 I2S Channels to them like on my Crazy Plan to use 2 MOTU UL at the same Time or even 2x 8 Channel DAC Sync on I2S Out form RPI 5 1 and 2 (at all 8 I2S Outs, 16 Analogue Channels) or Async USB (Topping DM7, MOTU...).

Any chance that this devices runs neare syncrone ???? They get his Input I2S Clocks at the same time and you could use one SPDIF out from MOTU 1 to Sync the Motu 2

Will this makes sense or may be a bit of sense???

would be realy nice if i could use something like 2x Topping D7 instead of one MOTU Ao24 or 16, Pricly a bit cheeper and even better specs i guess, dont need all the studio stuff on the Motu's

The Timedelay between The Channels could be corected with an Delay on Camilla , on surround settup you need to set the Delays for ech Speaker to be correct so anyway.

And if i want to listen Stereo i need only one RPI and can switch the other Chain off independant, (RPI 2+DAC Off)

Most time i listen Stereo so only for an Movie i need all Channels or for some Surround Music.

There is by sure an Time drift between two RPI's but how much coud it be???

2 USB DACS at the same time on one RPI5 with Camilla isnt' working right?

Found that:

https://medium.com/home-wireless/how-to-run-camilladsp-with-multiple-dacs-9672a4639cf3

1/4 ms timeshift betwen 2 same USB Dacs so not an good idea i guess ;(
The Problem is it seems not to be every time the same so you cant compensate it with fix Delay on Camilla per Channel
So better to use one 16 Channel Dac on one RPI at least.

Robert

 

[renne]

Hello Experts this crazy german Guy has an stupid idea and need Advise!

If i use 2 RPI 5 with same Software (Camilla DSP) and spread my 4 I2S Channels to them like on my Crazy Plan to use 2 MOTU UL at the same Time or even 2x 8 Channel DAC Sync on I2S Out form RPI 5 1 and 2 (at all 8 I2S Outs, 16 Analogue Channels) or Async USB (Topping DM7, MOTU...).

Any chance that this devices runs neare syncrone ???? They get his Input I2S Clocks at the same time and you could use one SPDIF out from MOTU 1 to Sync the Motu 2

Will this makes sense or may be a bit of sense???

would be realy nice if i could use something like 2x Topping D7 instead of one MOTU Ao24 or 16, Pricly a bit cheeper and even better specs i guess, dont need all the studio stuff on the Motu's

The Timedelay between The Channels could be corected with an Delay on Camilla , on surround settup you need to set the Delays for ech Speaker to be correct so anyway.

And if i want to listen Stereo i need only one RPI and can switch the other Chain off independant, (RPI 2+DAC Off)

Most time i listen Stereo so only for an Movie i need all Channels or for some Surround Music.

There is by sure an Time drift between two RPI's but how much coud it be???

2 USB DACS at the same time on one RPI5 with Camilla isnt' working right?

Found that:

https://medium.com/home-wireless/how-to-run-camilladsp-with-multiple-dacs-9672a4639cf3

1/4 ms timeshift betwen 2 same USB Dacs so not an good idea i guess ;(
The Problem is it seems not to be every time the same so you cant compensate it with fix Delay on Camilla per Channel
So better to use one 16 Channel Dac on one RPI at least.

Robert

How about 8 I²S-DAC chips like PCM1502A (4 per RPi5) connected to the MCLK of the 1st ASRC?
That way everything should be synchronous without the need to handle asynchronous USB.

 

[Frunse]

How about 8 I²S-DAC chips like PCM1502A (4 per RPi5) connected to the MCLK of the 1st ASRC?
That way everything should be synchronous without the need to handle asynchronous USB.

I would go for sabre dacs i like them, PCM5102A has only -93db THD+N thats not realy good, Sabre Dacs are 20dB better there. And have also 32Bit.

The Bigest Problem i see on the 2 RPIs. May be with this new Kernel you are able to Provide An External Clock to them but you never knows will both Camilla starts at the same time his datastream they need first to fill his Caches before the Music plays and they dont know from each other so thats something that need to test i gues. I could order one second RPI5 thats not much money and measure the I2S Outs for the Streams. befor i invest in DACS. The Pi i could use for else stuff if its not working.

They have normal quality 19.2 MHz clocks and they could differ up to 1/2 or 1 Clock between them and thats realy bad. They need both to have one same Clock thats the Minimum requirement i guess. And still, you dont has an Syncronisation between the two CamillaDSP Software. That why i it is an Crazy idea and makes al more Complicated.

And not Better but need to ask about .....

The Best would be to have an 16 Channel DAC but for now only Asyncrone (USB) possible. Only 4 I2S Stereo OUT's on one PI for now.

Topping, Motu need to build one
The Motu Ao24 is the closest option for now for me but only 24dB In and didnt know what kind of dac's there cant find Information about, MOTU 16A and UL (Newer, aktual Versions) has Sabre dacs.

Also you can buy an Black Lion Mod to make that Motu 24Ao even Better but Cost alot:
https://www.blacklionaudio.com/store/modifications/motu-24ao-mod/

https://www.motunation.com/forum/viewtopic.php?t=28310
Small A B Test (Review)

May be i talk to Much ad say nothing so please dont judge me to much
I am Interest in this stuff and like to build an nice solution without lots of knowing i fear

Robert

 

[phofman]

@Frunse: Here is an almost exact project what you would need https://github.com/raptorlightning/I2S-Hat - measuring LRCLK samplerate with arduino, communicating the momentary samplerate to RPi over GPIOs, python script which runs CDSP with correct samplerate config triggered by GPIO change, all sources available. You would only need to modify the arduino INO to remove the communication with the SPDIF receiver, because you do not need to distinguish between I2S signal from incoming SPDIF and I2S when the receiver is freewheeling with no input signal + maybe some minor changes. The python could be as is, IMO.

 

[Frunse]

@Frunse: Here is an almost exact project what you would need https://github.com/raptorlightning/I2S-Hat - measuring LRCLK samplerate with arduino, communicating the momentary samplerate to RPi over GPIOs, python script which runs CDSP with correct samplerate config triggered by GPIO change, all sources available. You would only need to modify the arduino INO to remove the communication with the SPDIF receiver, because you do not need to distinguish between I2S signal from incoming SPDIF and I2S when the receiver is freewheeling with no input signal + maybe some minor changes. The python could be as is, IMO.

That i need to investigate by sure thank you, very nice.

Ok removed the unnessery Parts from schematic, looks easy
I will try to add an Text Display or this Adafruit_SSD1306 Oled Display, let see and i use an Arduino UNO i still have from Ian's FIFO

Removed the unnasesary Code for all that SPDIF and WM8804 Initialising and switching.

now i will test it but need to buy some Parts like
BSS138
sn74lv1t34

Ad the end may be i could switch the I2S Switches by removing its Microcontroller and add the controllines to Arduino UNO also of this Dlatches and put them also onto the HAT
Thats would be an complete Solution but it could take some time. Nice Project anyway.

So 4 8 Channel I2S Input's with R.FL Conectors and Rate detection on one HAT. UNO and Display on another Board.

Will test the Sampllerate detection on Arduino with an Sinewavegenerator till i get all other Parts.

Test done Arduino working already and detects Frequencies from Generator

On that Character Display i need to change the rs Pin from D8 to D0, D8 is the only TCP1 Pin on Arduino UNO and cant get changed
https://www.roboter-bausatz.de/p/lcd-keypad-shield-mit-display-1602


Robert

 

[Frunse]

That i need to investigate by sure thank you, very nice.

Ok removed the unnessery Parts from schematic, looks easy
I will try to add an Text Display or this Adafruit_SSD1306 Oled Display, let see and i use an Arduino UNO i still have from Ian's FIFO

Removed the unnasesary Code for all that SPDIF and WM8804 Initialising and switching.

now i will test it but need to buy some Parts like
BSS138
sn74lv1t34

Ad the end may be i could switch the I2S Switches by removing its Microcontroller and add the controllines to Arduino UNO also of this Dlatches and put them also onto the HAT
Thats would be an complete Solution but it could take some time. Nice Project anyway.

So 4 8 Channel I2S Input's with R.FL Conectors and Rate detection on one HAT. UNO and Display on another Board.

Will test the Sampllerate detection on Arduino with an Sinewavegenerator till i get all other Parts.

Test done Arduino working already and detects Frequencies from Generator

On that Character Display i need to change the rs Pin from D8 to D0, D8 is the only TCP1 Pin on Arduino UNO and cant get changed
https://www.roboter-bausatz.de/p/lcd-keypad-shield-mit-display-1602


Robert

So the Andruid UNO Sofware is done, now i can swith between I2S Inputs with 4 Buttons.
For the first Prototype its enough to play with.
Need now to wait till al Boards arived and the Parts.
Till there i need to Learn KICad dont want to use the older Eagle 7 again (Limited to 160x100mm Board my Version so anyway) or pay to Autodesk for new Version.
And Start with the PI HAT from Scratch.

First Board i want to engrave with CNC, if all works i could order some PCB'S from PCB Shop

Looks if its would go this way

Robert

 

[phofman]

@Frunse : congrats to your project advancement. Just a note - is it necessary to use the 3.3-> 5V the level shifters? Those small Arduino boards are available at 3.3V too, I used them a few times. Typically they run only at 8MHz but can be switched to 16MHz if needed, AFAIR, but probably not needed for this project anyway.

 

[Frunse]

@Frunse : congrats to your project advancement. Just a note - is it necessary to use the 3.3-> 5V the level shifters? Those small Arduino boards are available at 3.3V too, I used them a few times. Typically they run only at 8MHz but can be switched to 16MHz if needed, AFAIR, but probably not needed for this project anyway.

Yes i saw that on the ordered I2S Board it has an 3.3V Regulator but still dont got it, i need to wait till i get it. But Raspi has also 3.3 V right?
Probably that why this guy use this BAS138 N-Channel FET between Nano and Raspi GPIO i will use them too.

If i did the Schematic i wil post it here so you guys could do an check please If i think about all Possibilities.

I am also thinking to use the I2C Bus with Channel expansion (PCF8574) on the Hat for the 3 Dataline Rateswitch and 4 Line for Dlatch Control so not much Wires needet
Also want an other Display Wite Character on Black Backround or may be Dot Display or anything like that.

Wishlist:
Flirc Remote 2 GPIO lines for switching Dlatches Remotly 00=I2S1 10=I2S2 01=I2S3....
2 Lines for Volumecontrol the RelaisBoards Up, Down
So I2C to 8x IN and I2C to 8xOut on the Hat would do it (PCF8574)
May be Display also I2C need to check what kind of nice stuff i could get

Found this Character I2C Displays (Bought both):
https://www.ebay.de/itm/303252608110
https://www.ebay.de/itm/293187314158



Thank you

Robert

 

[phofman]

IMO the HDMI I2S is 3.3V (most likely), RPi is 3.3V, maybe 5V tolerant, I do not know. IMO the 3.3V arduino is the correct choice.

 

[renne]

IMO the HDMI I2S is 3.3V (most likely), RPi is 3.3V, maybe 5V tolerant, I do not know. IMO the 3.3V arduino is the correct choice.

Is the MCLK of the HDMI audio extractor source or sink?
Is the HDMI audio extractor an I²S master or slave device?

 

[MCH]

Is the MCLK of the HDMI audio extractor source or sink?
Is the HDMI audio extractor an I²S master or slave device?

I don't know the specific one discussed here, but these HDMI to 8 channel i2s in general (the ones I know) are based on chips that support both master and slave mode but normally come wired as master only.
My mistake: the input i2s in EP92AE3 (pins 120-122) does not have MCLK input, I was remembering wrong.

By the way, upon checking AliExpress I have seen a new much cheaper one that I had not seen before. Also based on a Explore chip. It can be interesting for people attempting multichannel on a pi 5. At 30 euros shipped I believe is the cheapest option available:


€27.28 26%OFF | HDMI Separates Digital Audio I2S/ Coaxial/Fiber/multi-channel DSDS

https://a.aliexpress.com/_ExXDZcD

 

[phofman]

Since HDMI is the clock master, I am not sure how the HDMI receiver would handle the I2S slave mode. IIUC that chip has also I2S receiver for the HDMI output audio, perhaps that one is slave.

Also the block diagram of EP92A3E (I could not find any datasheet) suggests the I2S transmitter is master including the MCLK signal

 

[Frunse]

I don't know the specific one discussed here, but these HDMI to 8 channel i2s in general (the ones I know) are based on chips that support both master and slave mode but normally come wired as master only.
By the way, upon checking AliExpress I have seen a new much cheaper one that I had not seen before. Also based on a Explore chip. It can be interesting for people attempting multichannel on a pi 5. At 30 euros shipped I believe is the cheapest option available:


€27.28 26%OFF | HDMI Separates Digital Audio I2S/ Coaxial/Fiber/multi-channel DSDS

https://a.aliexpress.com/_ExXDZcD

Hello MCH i saw this HDMI to I2S Board as i ordered the other one, because on the Board is written 6 CH HDMI to I2S and not 8CH that makes me Skeptical not sure what does it mean.

But 4 I2S Lines SD0-SD3 you can see there also, not sure about this. May be a mistake by them.

On the description they say I2S up to 7.1 Suport, DSD max 5.1 \0/
I will order one and test it
Bought it ariving around 15 April

Robert

 

[renne]

Since HDMI is the clock master, I am not sure how the HDMI receiver would handle the I2S slave mode. IIUC that chip has also I2S receiver for the HDMI output audio, perhaps that one is slave.

Also the block diagram of EP92A3E (I could not find any datasheet) suggests the I2S transmitter is master including the MCLK signal

Does the EP92A3E support eARC/HDMI 2.1?

 

[MCH]

Does the EP92A3E support eARC/HDMI 2.1?

Only ARC