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

Hey all, just a little update on my "glitch" or "skip" issue. I thought I emailed the manufacturer a week ago, but I looked yesterday and that email was still sitting in my "Drafts" folder. I never sent it... /facepalm.

But he did get back to me yesterday and he has seen an instance where this seems like it was happening and he described it as a FIFO overrun condition in the DAC, however it was not from an i2S source like HDMIPi. So, his thought is that the i2S interface in my DAC is fubar, somehow. We're probably going to try one of the Denafrips reclockers first as a troubleshooting measure - known good i2S source, see if the issue repeats in my setup - and if it does, my DAC will need to be fixed or replaced or whatever's easiest there.

It was nice to see no blame laid at the feet of Ian's stuff or my DIY, uh, skills. We'll see - I can definitely say I miss not having FIFOPi and HDMIPi in the signal chain. There's just something "extra" to the sound with it in the mix between my Pi and the DAC. And I will probably end up putting it back in soon, and just deal with the skips until we can sort it all out. They're not that bad.
 
As I have reported several times, I have the exact same kind of click/snap. In my case it is always in the left channel but it is not consistent. When it occurs it is when I hit play, and I think it may also be when the source data rate changes between tracks. IE the playlist has 2 tracks at 44.1 then a track at 88.2 I might see a snap when I hit play then two tracks will play without issue but a snap when the 88.2 track starts. In my case it is a very low volume snap that sounds like static electricity discharging like you may hear on an LP. It is easily ignored so its not an issue for me. It is disconcerting that others are having a pop loud enough that it could hurt a speaker. This did not happen for many months of FIFOpi use. Then it has started and is not consistent in its pattern. I almost never make changes to my system so it is not as a result of change in configuration.
 
Thank you for your feedback. This is exactly the same issue I have. Yes, the click is mostly on the left side and sounds like static electricity discharging. In my system the click sometimes reaches the maximum level which is set on my integrated amp. Luckily most of the time the click has lower level, but easy to hear. About 1 of 10 times it is on maximul level. I am afraid that my speaker will not like this on a longer term!? I do have the Fifo PI since end of january and the issue was from the beginning. First I thought I can fix it somehow but now I'm not sure anymore. There are not that many people having problems with it so I think maybe mine is just broken!?

May I ask you which setup you run? Do you also use RPI with volumio as a source?

I'm not sure what to do next. I think I will contact my dealer (online shop in france) to ask if they can change the Fifo Pi. Not sure if this is possible for DIY stuff like this...
 
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I’ve been reading and searching through this thread but could not find how most people here handle a graceful shutdown of their pi.

Volumio prefers to be shutdown, i believe that can be done by wiring a button to GPIO and leverage a gpio plugin. But then, would the pi itself be able to function as a a switch to turn off the linearpi supply which itself is running in continuous ac mode?

Any experiences or best practices
 
I’ve been reading and searching through this thread but could not find how most people here handle a graceful shutdown of their pi.

Volumio prefers to be shutdown, i believe that can be done by wiring a button to GPIO and leverage a gpio plugin. But then, would the pi itself be able to function as a a switch to turn off the linearpi supply which itself is running in continuous ac mode?

Any experiences or best practices
Using IR remote plugin with IR receiver and remote Justboom you can shut down the pi properly.
I always do like that. Maybe that's an option too.
 
Hi,



coming from the DDDAC thread, I need some help please regarding FIFO Pi Q3.



I have it in my system for quite some time now. I'm very pleased soundwise when a track is running, no pop / clicks, very clean and detailed sound, great soundstage.



But there is one issue I'm struggling with: When I start playing a new track or jumping to a new position within the same song, there is often one short (loud) click / pop. After that the track plays without issues with great sound. The click volume differs, sometimes it is quiet I can almost not hear it, but most of the times it is really loud and I'm afraid that my speaker get broken!?! Also the 'position' of the click moves: Most of the time on the left side, sometimes the click moves to the middle and right side of the soundstage. Really strange.



I have done some tests but to summarize:

RPI I2S -> FIFO PI Q3 -> DDDAC: Clicks and Pops at track start

RPI I2S -> DDDAC: no issues



I'm running volumio, but I have also tested with moode. Same issue.



...



Do you have an idea? Someone with the same issues? I would really love to keep the FIFO PI in the system because sound is great when track is running, but the clicks in the beginning are driving me crazy...

Hi, I have the same little clicks, indeed mostly on the left side. But they are not high volume. I use Volumio, didn't test with other images.
I use raspi, stationpi, fifopi q2, i2s directly to tda1541a dac.
Indeed without fifopi no clicks. I try to ignore them. [emoji4]

I will do some further tests of they occur with different sample rates.

Let's hope we can find the cause of this. The fifopi is a nice thing and I have no intention to replace it[emoji4]

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Project Update

After my initial learning curve early 2021, I decided to just focus on desktop going forward. I'm giving up indefinitely any portable or transportable projects. I'm also giving up on the RPi / StationPi on the desktop and moving towards a PC-based SPDIF-OUT (No WIFI) via 13.2V rail from the MKIII solution to feed a ReceiverPi (3.3V).

This allows me not only to be off 5V, but also to focus exclusively on the Andrea Mori clock. I had wanted MagicXtal because if MOQ is 5 and if I have 3-5 FiFoPi systems, that makes sense. But now since I put behind any portable or transportable, I can focus all my attention on Andrea Mori clock.

The lessons learned comes at cost. I fried a FiFoPi Q3, a A123 18650 battery, a A123 26650 and 3 BMS. I can't even calculate all unplanned Mouser / Digikey parts I went through, but I chalk it up to just paying for DIY lessons and gaining good experience in this hobby.

I'm happy to report I finished assembling the MKIII and that went smoothly and rock solid.

During the process to try to make the Q3 portable, I had to remove the power terminals to make it fit the case. After many iterations of soldering on the Q3 PCB, it finally gave out and shorted. I realised now the problem was the Q3 short all along. I had soldered my BMS properly, but for some reason it always fried. It was frustrating and confused me. But now I understand I shorted the Q3 so no matter how careful I was soldering the BMS, there was no chance for everything to work because I didn't recognise the Q3 short at that time.

Well, moving on... After some more Mouser parts, will tackle the Ultra Caps on top of the MKIII end of the month,

Desktop is pretty straightforward. Experimenting with portable is a challenge, but it helps by gaining experience for the Desktop build. I'm feeling more confident to tackle the Andrea Mori clocks down the road. Finished board only of course...
 
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Hi, I have the same little clicks, indeed mostly on the left side. But they are not high volume. I use Volumio, didn't test with other images.
I use raspi, stationpi, fifopi q2, i2s directly to tda1541a dac.
Indeed without fifopi no clicks. I try to ignore them. [emoji4]

I will do some further tests of they occur with different sample rates.

Let's hope we can find the cause of this. The fifopi is a nice thing and I have no intention to replace it[emoji4]

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Thank you for your feedback! In my system I think the issue is not related to the sample rate. I have the same issue when I jump from one song to another of the same album and artist (all tracks in red book format). I'm wondering if the issue is present on all fifopi copies but with different click levels!? Or the click in my system is louder because I have a sensitve AMT tweeter!?
I have asked my dealer for a exchange. Hopefully with success. If I get a new copy I will let you now, if the click is gone or click level has changed.
 
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With portable and transportable projects in rear-view mirror, I can focus solely on desktop.

So it begins...
 

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Thank you for your feedback! In my system I think the ...

Or the click in my system is louder because I have a sensitve AMT tweeter!?

I have asked my dealer for a exchange. Hopefully with success. If I get a new copy I will let you now, if the click is gone or click level has changed.

Don't know if it is sample rate related. This weekend I can do some test, also of the click is not that within the same album.

I have Dynaudio Esotec tweeters in my system. Maybe a bit less sensitive. Could be[emoji4]

Let's see if the click is gone with another fifopi. Is it Q2 or Q3 model?

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@A123

Your LifePO4 power supply looks very nice. A professional built!

Ian

Thank you. That means super much to me.

I'm writing this from a NUC powered by a MKIII 13.2V rail. I want to put the MKIII through it's paces before ordering a 13.2V-powered motherboard w/ SPDIF-OUT. Looking forward to how this desktop project turns out in the long run.
 
Accusilicon AS338 x 2 on the way

Since there seems to have been interest in the Accusilicon AS338 on this thread, here's an update so we stay ahead-

Taobao Focus has them on this page Loading.. Please wait. #637951115161 Taobao FOCUS

AS confirmed vendor status at an earlier stage.

With shipping etc, the fee per each grew...

...to a total of close to $200 for 2.

They sent me this pic of my goodies today.
And I paid for shipping, they'll be on the way.

I hope DHS gets them to my door before too late.
I'll stick 'em on FIfoPi and see if they sound great.

Regardless, I'll let you know how they sound as soon as the little buggers are around.
 

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Nice JCmC. I for one appreciate the efforts to try these out for 'us'!
Not cheap and getting around the Andrea Mori clock prices....I know he has various versions at different costs......but these AS338 are atleast plug and play onto Ians boards and much easier to implement.
 
Plug and play

Nice JCmC. I for one appreciate the efforts to try these out for 'us'!
Not cheap and getting around the Andrea Mori clock prices....I know he has various versions at different costs......but these AS338 are atleast plug and play onto Ians boards and much easier to implement.

Yes, Jim the point is quick plug and play.

I’ll likely try Andrea’s clocks another day.
 
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