AK4499 DAC Design

I now have a set of Grzegorz' (aka piglet11) PCBs. Excellent work! Thank you! My buildout plans vary a little, mostly in my choice of supporting parts, so having a ready-made PCB available is going to save me a lot of headaches designing and making my one one-off. The real problem seems to be locating the 4499 chip itself these days. Hopefully that will be resolved sooner than later. I plan to post pics of my progress.
 

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Hi,
Sory for late answear.

I did my own version of PCB's for DAC.
1 - 4 layers board with AK4499, ultra low noise voltage regulators from LT.
2 - 2 layers board with analog part and pre stabilization voltage for Digital part.
3 - 2 layers board with amanero and arduino nano for parametrisation of DAC, volume regulation, OLED.

Third PCB will be replaced for new one 4 layers board with 5 digital inputs on AK4118 and one USB Amanero in my version with better voltage regulators, clocks, uC STM32.
To this board will be connected PCB with OLED 256x64.

If You want PCB, just write PW 🙂

I did some measurements, SNR less than 130 dB, 50 Hz harmonics does not exist 😀

What is the price for board 1 the one with the AK4499?
 
PCB with OLED is done 🙂
Now I writing software for OLED and user layer for management DAC and inputs selector.
Main screen should look more or less like on attached photo.
 

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I see that some members did some nice dacss with ak4499eq.
They surely know it better than I that I just modify them.
I have dac that is dual mono ak4499.
1.) can be put to voltage moude out, because it plays ok in just followed srpp output stage... you can swap dac board to ak4497 and ak4490 and es9038pro and all are followed with the same output stage with firmware updates of course.
2.) can be all IOUTP and all IOUTN summed prior I/V stage... i read in datasheet that all IOUT pins should not be connected. I have problems with clipping on IOUTP of VOUTP and VOUTN outputs. or in picture below DAC P OUT and DAC N OUT. So on scope upper part of sine wave is cut at 3/4 value.
Cipping is present at 0db out but not visible at -10db.
If this is not ok how will be best connection for dual mono out without I/V opamp stage?
 

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Its not designed to be used in voltage out mode. Its also not designed to parallel outputs before the I/V stages. If you want to use it in a way it wasn't designed for, then you are pretty much on your own. We could talk about ways that would try to use it more like it was designed for. After all, it should sound pretty good used as designed. If it doesn't sound good that way, then you may have some other problem.