Asynchronous I2S FIFO project, an ultimate weapon to fight the jitter

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Well, okay. What would you suggest? Go for Italian if that suits your fancy? ?
Hello,
I wanna find the first copy of digital audio for dummies.
The possibilities are endless and some people take the wrong turn and end up in a dark lit parking lot.
I always compare it to a good old turntable. Some choices to be made there too but no matter which choices you make there will be music.
With digital just one setting wrong it will be no music at all.
Greetings Eduard
My clocks are Italian, so are some of my wines. Canada has boards too i know
 
From the McFifo manual I got this:


MCH streamer is also supposed to run as master so I belive this would be the way to do it.
One problem though, it might just as well have been in Latin :confused:

I would connect it with the diagram in post 10,757 instead. Run the MCH streamer to the McFIFO without the MCLK. The option you quoted would require you to find the clocks on the MCH streamer and connect a u.fl. in place of the clocks and also connect XO selection pins which don’t exist. Don’t think that is feasible.
 
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Hi Pete,

I have a good news for you.
Last night, I did a test myself with the same configuration and figured out the issue.

Reason: TransportPi Digi works in master clock mode which needs two additional hardware connections for the clock selection, but the StationPi doesn't provide such connections.

Solution: Solder two wires at back side of the StationPi PCB to connect both pin29 and pin31 between GPIO socket J1 and connector J7, please see the picture.

Result: Works like a charm no longer has any issue

Thank you so much for reporting the issue. Sorry for my late solution. Good luck to your project.

Ian
Thank you for investigating. I'll implement this tonight.

Now I can go back to investigating a new linear power supply for the Pi5, as it appears to be a power hog.

Keep up the great work, Ian.

Pete
 
I would connect it with the diagram in post 10,757 instead. Run the MCH streamer to the McFIFO without the MCLK. The option you quoted would require you to find the clocks on the MCH streamer and connect a u.fl. in place of the clocks and also connect XO selection pins which don’t exist. Don’t think that is feasible.
Ok, so you say it will still work. That's a relief :cool: .

Best regards. Bengt
 
I am also interested in help regarding this issue. Had identical symptoms when setting up LinearPi Duo for a symmetrical power supply. Then, after a few rounds of trying to get them to work properly and powering up and down, the position of the ON-OFF switches stopped making any difference. Both LinearPi are turned on permanently regardless of the ON-OFF switch position. Power out LED light on one LinearPi is permanently light up, the second one not, but both constantly provide correct voltages at their outputs.
In this case you agree with me that there is no mistake in my basic topology? It is is quite odd behaviour of the linearPi.
 
@brando.bern Now, reading again what you wrote I think you made a mistake in the topology. You wrote:

The setup: Linearpi1 delivers +5VDC and the -5VDC is connected to the +5VDC of the LinearPi2. LinearPi2 delivers -5VDC and, together with LinearPi1 should create 0VDC.

The wiring should be as follows - to + between LinearPi's provide 0V and then you take +5V and -5V from two different LineraPi, respectively.
Zrzut ekranu 2023-12-7 o 10.14.09.png


What you wrote is that you tried to take -5V from the +5V on the LinearPi2, which is incorrect.
 
I beg to differ. I do not see the reason why I would need 3 power LinerarPis to power the opa861.
Following the recommendations of @Gabster 2000 I first powered the opa861with two 5vdc wall-warts (not 3) and it woked flawlessly -- but also with too much noise for my taste. What is the difference to the topology below?

dual rail.png
This is correct This is how I meant it should be connected. Two LinearPi in total :)
 
Just to add a data point: I also have distortion (static noise) with 176 and 192 PCM files although my setup is different:
RPi4, StationPi Pro, FifoPi Q7 and HDMIPi Pro, powered by PurePi II with UcConditioner II 3.3V.

An Amanero board is on the way, and I am hoping that this will enable up to PCM384 and DSD512.
I have the same setup and have distortion on PCM 176 and up
 
@kiwibirch @bodiebill

I have the same setup without any problem. But according to my experiences, normally it's the DAC issue.

To user I2S over HDMI input, a DAC are normally with conditions
1. MCLK frequencies
2. HDMI protocol
3. Mute signal positive enable or negative enable
4. DSDEN signal positive enable or negative enable

You can refer to this HdmiPiPro user's manual for configuration examples of different DACs
https://github.com/iancanada/DocumentDownload/blob/master/HDMIpi/HdmiPiPro/HdmiPiProManual.pdf

To address the issue, you have to locate the problem first.
 
I received a SC-Pure 45 clock yesterday and installed it into my FifoPiQ7. I want to share my first impression which are a little bit mixed. There is an clear improvement in soundstage and 3D-image. I can better hear the room in the recording and there is more reverb in voices and instruments. I really like this. But on the other hand there is also some harshness, especially in voices and some instruments like violins. The standard clocks (Accusilicon) are sweeter to my ears. The SC-Pure has not the tight contact to the socket like the standard clocks have and there is a little air gap between clock and socket. But I think this is how it is intended!? I hope break in will help for the harshness thing; If break in is something which really exists (I have never had a positive break in experience before :))? Or maybe there is something wrong with my copy of SC-Pure? From the clock comparsion table I would expect that SC-Pure is at least on par with Accus even for sweetnes in voices!? Or maybe my system / chain is not compatible!? I have a 49 standard clock installed in the other socket. Is this an issue? At the moment I'm not sure if I would trade in the improvements in soundstage and reverb for the sweeter voices and musicality of the standard clocks.

My system: RPI powered via LinearPi and UCC, FifoPi Q7 powered via LifePo4Mini and UCC, 4 stack DDDAC with good power supply.
 
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I somehow still cannot get my StationPi Pro running successfully. I did study every related hat menu for multiple times.

I use Ropieee naa to send DOP-64 signal through GPIN40. choosing Generic I2s hat output. Set the DOP decoder enable to transfer DOP-64 signal to native DSD64 on FifoPi Q3. Then send to HdmiPi Pro to connect to my Dac. Everything is good, it works as expected.

The weird thing is that when I install the rp4 under the FifopiQ3 like people normally do, It works without problem. However, when adding the StationPi Pro into the set up with exact same setting( Ropieee Generic I2s hat output and fifopiQ3 setting). It becomes very loud noise. The Fifopi light shows it locked into DSD signal successfully. :unsure: I didnt install amanero usb, so it wont be the problem.

I guess it demonstrates that my stationPi Pro setting is wrong or demaged?
WhatsApp 圖片2023-12-0811.05.14_c2188fe9.jpg

WhatsApp 圖片2023-12-0811.05.14_a86bfa6d.jpg

WhatsApp 圖片2023-12-0811.05.14_c2188fe9.jpg
 
@kiwibirch @bodiebill

I have the same setup without any problem. But according to my experiences, normally it's the DAC issue.

To user I2S over HDMI input, a DAC are normally with conditions
1. MCLK frequencies
2. HDMI protocol
3. Mute signal positive enable or negative enable
4. DSDEN signal positive enable or negative enable

You can refer to this HdmiPiPro user's manual for configuration examples of different DACs
https://github.com/iancanada/DocumentDownload/blob/master/HDMIpi/HdmiPiPro/HdmiPiProManual.pdf

To address the issue, you have to locate the problem first.
Thanks Ian. Comparing the HdmiPi Pro and my Leaf CMD27 DAC's protocols:

1702033762805.png
1702033826761.png


Do you see a discrepancy that explains the distortion with PCM176 and upwards?
Anything I could try? (Still waiting for a MonitorPi Pro...)

Am I wrong to think that the fact that everything plays well up to PCM96 shows that the I2S/hdmi formats are compatible?

I saw that some others experienced the same problem, maybe they could chime in, sharing info/I2S format of their DACs?
 
I received a SC-Pure 45 clock yesterday and installed it into my FifoPiQ7. I want to share my first impression which are a little bit mixed. There is an clear improvement in soundstage and 3D-image. I can better hear the room in the recording and there is more reverb in voices and instruments. I really like this. But on the other hand there is also some harshness, especially in voices and some instruments like violins. The standard clocks (Accusilicon) are sweeter to my ears. The SC-Pure has not the tight contact to the socket like the standard clocks have and there is a little air gap between clock and socket. But I think this is how it is intended!? I hope break in will help for the harshness thing; If break in is something which really exists (I have never had a positive break in experience before :))? Or maybe there is something wrong with my copy of SC-Pure? From the clock comparsion table I would expect that SC-Pure is at least on par with Accus even for sweetnes in voices!? Or maybe my system / chain is not compatible!? I have a 49 standard clock installed in the other socket. Is this an issue? At the moment I'm not sure if I would trade in the improvements in soundstage and reverb for the sweeter voices and musicality of the standard clocks.

My system: RPI powered via LinearPi and UCC, FifoPi Q7 powered via LifePo4Mini and UCC, 4 stack DDDAC with good power supply.
Give it minimum of 200 hours of play time, then compare.
 
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I received a SC-Pure 45 clock yesterday and installed it into my FifoPiQ7. I want to share my first impression which are a little bit mixed. There is an clear improvement in soundstage and 3D-image. I can better hear the room in the recording and there is more reverb in voices and instruments. I really like this. But on the other hand there is also some harshness, especially in voices and some instruments like violins. The standard clocks (Accusilicon) are sweeter to my ears. The SC-Pure has not the tight contact to the socket like the standard clocks have and there is a little air gap between clock and socket. But I think this is how it is intended!? I hope break in will help for the harshness thing; If break in is something which really exists (I have never had a positive break in experience before :))? Or maybe there is something wrong with my copy of SC-Pure? From the clock comparsion table I would expect that SC-Pure is at least on par with Accus even for sweetnes in voices!? Or maybe my system / chain is not compatible!? I have a 49 standard clock installed in the other socket. Is this an issue? At the moment I'm not sure if I would trade in the improvements in soundstage and reverb for the sweeter voices and musicality of the standard clocks.

My system: RPI powered via LinearPi and UCC, FifoPi Q7 powered via LifePo4Mini and UCC, 4 stack DDDAC with good power supply.

Perhaps seen as voodoo by some here, but I will put Tungsten cubes on my SC-Pure clocks.
 
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