Simple DSD SRC for BeagleBone

I take my words back. SRC4192+AK4137 sounds very good.
The problem was with the fake SRC4192 chip. The donor was a board purchased in China on Aliexpress. After I bought the chip from a reputable supplier, everything fell into place.


I made a mini version of DSD'it for Amanero in slave mode. And I am very pleased with the result.
I can't hear the DSC2 murmur on the test tracks. In the 2xAK4137 variant, murmur can sometimes be heard.
 

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Hi pavel,
it will be something for public release ?

i am interested to listen to the new DSC you showed in the photos...
the fact that you blurred the silkscreen led me thing it would fit some "commercial" products... so my hope is very short 🙁

thanks for all your efforts !
 
I would publish all my developments. But now not everything depends on my desire.
Yes, indeed, there will be a commercial project of a finished device soon. But what you saw in the photo is just a prototype. The design of the finished product will be different.
 
The shortage of IC AK4137 is still large.
In DSD'it, you can reduce the number and use the TI SRC4121 chip in the first stage.
I'm sure it won't degrade the sound. But for this you have to redo the PCB.

There are still people selling AK4137 at high prices on the Chinese store platform, for example, the one below, which sells for about US$50. In recent months, there are still transaction records and it seems that the credit is good. If necessary, I can help to buy it. Aliexpress is a sales platform for foreigners, so Aliexpress will charge a very high handling fee, so the price will be much higher.

AKM AK4137 AK4137EQ 2ch 32bit SRC?????IC ???????-???
 
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AliExpress is very different from Taobao. Operating costs on AliExpress are very high. If you want fast speed, I can also find express delivery within a few days. However, it looks like you don't need it.

I don't want to share the results of my own research and development at all, so seeing you share the technical details generously, I really want to help.
 
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Hi ppy,

I need a dual KA4137 board, which has a 40-pin SMD pin on the front and back, so that the Pi’s i2s output is transmitted to the KA4137, and then PCM signal from the Pi is Upscaled to the DSD signal through KA4137, and the DSD signal is transmitted to Ian's Reclock through another 40-pin SMD pin on the front.

I will pay you. Can you help design such a dual KA4137 board? I only need the designed PCB file, and I can find a factory to make it myself. There are many fans of iancanada, and there should be quite a good market demand.
 
I thought of an easier solution. I designed a conversion board between your SRC board and Ian's STATIONPI, so that the I2S output of your SRC board can be passed to Ian's reclock via STATIONPI. If I am right, I only need to pass the LRCK, DSDCLK, and DATA output from J4 of your SRC board to PiWS (LRCK), PiSCK (SCK), PiSD (DATA) of J1 of Ian's STATIONPI respectively. This should be correct, right?

In addition, is there any new version of your SRC board for sale?

supportp2i.jpg

ianca.jpg

1625081168583.jpg
 
If someone wanted to drive a circuit similar to DSD'it from RPi, a good way to do it would be via asynchronous USB, not via RPI GPIO I2S bus. With a galvanically isolated USB card, FIFO-Pi would not be needed. A FIFO (or maybe an ASRC) could still be needed for things like SPDIF or maybe HDMI. Just sayin'
 
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