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

further to previous comments I've now had an extended listen against my new Gustard A18 akm4499 dac. While there's not a lot to separate them my iancanada stack feels a smidge more expressive dynamically, it sounds a few rows closer to the stage in terms of presentation and its a little, very little, drier in the bass overall. The Gustard is a touch fuller, more extended but also has a little bit of bloom that I don't think entirely without artiface.

Overall the lifepo, fifopi, ess9038qm dual dac stack is still marginally ahead.
 
Last time I looked there was a free trial version of HQ Player that would run with all features enabled for 30 minutes at a time. Sounds pretty nice with DSD256 or DSD512 using the Adaptive DSD512+ modulator. Definitely worth a try. You might find you like it a lot, or maybe you won't care much. Only one way to find out.
 
further to previous comments I've now had an extended listen against my new Gustard A18 akm4499 dac. While there's not a lot to separate them my iancanada stack feels a smidge more expressive dynamically, it sounds a few rows closer to the stage in terms of presentation and its a little, very little, drier in the bass overall. The Gustard is a touch fuller, more extended but also has a little bit of bloom that I don't think entirely without artiface.

Overall the lifepo, fifopi, ess9038qm dual dac stack is still marginally ahead.

That's very interesting.
My FifoPi + ES9038Q2M DM + Transform I/V + PulSar 90/98+ LifePO4 MKIII with UcMateConditioner and UcHybris is still the best sound DAC I have ever had. I think the true SYNC mode could be the one of the most important reason.

I bought a Topping D90 to feel AKM4499. Seems not as good as I expected. With a bit disappoint. I'll try more different settings later when I have time. I'm wondering if I there is any improvement I can make.

Ian
 
And isolation from the noisy Pi.

Unfortunately, StationPi will not be useful. As in the photo I attached, I used three very thick aluminum boxes. The leftmost box contains FifoPi, ReceiverPi and raspberry pi, the middle box contains McFIFO and McDualXO, the rightmost box contains twisted's BUFFALO-IIISE PRO, and the back and big box contains power modules and transformers. If you want to talk about noise isolation, this should already be the best. However, after working hard to build a bunch of boxes, it is actually best way is a well-designed grounding box connected to BUFFALO.

The reason is very simple. The grounding box directly absorbs all kinds of noise, unlike these boxes or isolation methods. The noise is still in the original place and continues to affect FifoPi, raspberry pi, McFIFO, McDualXO, and BUFFALO-IIISE PRO.

Instead of spending time to design StationPi , it is better to design a metal cover for the clock, such as the middle box in my photo.

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If you want to improve the Raspberry Pi's noise problem, in fact, the improvement method is not from an external power supply, nor is it to buy StationPi, but to remove the very bad built-in DC-DC power supply of the Raspberry Pi, and then supply power separately from the outside PP5: GND, PP7 : 5V, PP8: 3.3V and pp9: 1.8V. That is, first remove the built-in DC-DC power supply of the Raspberry Pi in the photo. For details, please refer to the Raspberry Pi manual.

Schematics - Raspberry Pi Documentation

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I bought a Topping D90 to feel AKM4499. Seems not as good as I expected. With a bit disappoint. I'll try more different settings later when I have time. I'm wondering if I there is any improvement I can make.

There are two first things you would need to do, both would make the dac cost more to buy: (1) use better clocks (with a better frequency divider if needed), and (2) use better Reference Voltage supplies/regulation (AKM's equivalent to AVCC).

EDIT: Might want to get rid of the mute circuitry too, maybe replace it with output shorting relays.

Then, use the best sounding upsampling to DSD you can manage.

Fact is, a commercial dac that sells for $700 can't include all the things it takes to make a great dac. How much do you have invested in your dual ES9038Q2M dac? More than $700 I would guess (maybe that much just in the Polartec clocks? How much would they cost today?). And still, it didn't come in a finished case, didn't come with a nice shipping box, doesn't have a Windows ASIO driver, isn't something just anyone could plug in and use, etc.
 
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There are two first things you would need to do, both would make the dac cost more to buy: (1) use better clocks (with a better frequency divider if needed), and (2) use better Reference Voltage supplies/regulation (AKM's equivalent to AVCC).

EDIT: Might want to get rid of the mute circuitry too, maybe replace it with output shorting relays.

Then, use the best sounding upsampling to DSD you can manage.

Fact is, a commercial dac that sells for $700 can't include all the things it takes to make a great dac. How much do you have invested in your dual ES9038Q2M dac? More than $700 I would guess (maybe that much just in the Polartec clocks? How much would they cost today?). And still, it didn't come in a finished case, didn't come with a nice shipping box, doesn't have a Windows ASIO driver, isn't something just anyone could plug in and use, etc.

Thanks Mark,

I'll do more test.

Regards,
Ian