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AK4490 USB Dac with dsd support.

I really do not know what you want.

You ask about features on PM and so on. You ask about schematics and i post them.

You then comment that even an LM741 is better!?

I really do not know what to believe about you. Serbia? mmhhh ... Are you affiliated with someone in the forum?

Now to give some impression here of the performance of the discrete at 10KHz. with 1Kohm load.

Harmonic Frequency Fourier Normalized Phase Normalized
Number [Hz] Component Component [degree] Phase [deg]
1 1.000e+04 2.000e+00 1.000e+00 171.53° 0.00°
2 2.000e+04 4.869e-06 2.434e-06 65.22° -106.31°
3 3.000e+04 6.168e-07 3.084e-07 -109.76° -281.29°
4 4.000e+04 6.568e-08 3.283e-08 165.88° -5.65°
5 5.000e+04 1.051e-08 5.252e-09 63.65° -107.89°
6 6.000e+04 1.303e-09 6.516e-10 -36.55° -208.08°
7 7.000e+04 1.851e-10 9.252e-11 -139.92° -311.45°
8 8.000e+04 2.592e-11 1.296e-11 134.14° -37.39°
9 9.000e+04 5.322e-12 2.661e-12 -164.56° -336.09°
Total Harmonic Distortion: 0.000245%(0.000247%)

And the FFT simulation is attached. I have real world measurement for the DAC also that backs it up.

BR

Sonny
 

Attachments

  • opampsimpel fft 10KHz and load 1K.pdf
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I don' believe you..
Atached file is for opamp..
Discrete output have 1% at 10kHz

!???!????????

Screendump attached!!!!! :confused:
 

Attachments

  • opampsimpel screendump.jpg
    opampsimpel screendump.jpg
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Never mind, I will find some time to make simulation from your schematic.. it is impossible to have such THD.. if your real measurements and simulation which screenshot you upload are same, there is nothing to 'use against you'..

vulejov,

Have you ever tried a 741 or a NE5532/34? They really don't make you jump off of your chair... If I speak for myself, and this is purely my own taste, the discrete output shield sounds REALLY amazing, nothing to ever compare against a NE5532, really.. Sonny also has an output shield based on ADA4898-1YRDZ if THD is what you like to listen to?!? Please buy the discrete output shield and listen to it, it is really a musical piece of equipment. I have both output shield and although the ADA4898-1YRDZ version is truly remarkable, I find the discrete one just more musical.

I'm not too sure if the argument is about musicality/Sound reproduction or THD figures, but if it has something to do with THD then I cannot comment since I do not own equipment precise enough to measure this. Anyways, not going to war with anyone here, just my subjective impressions of the output shield.

Ciao!
Do
 
Never mind, I will find some time to make simulation from your schematic.. it is impossible to have such THD.. if your real measurements and simulation which screenshot you upload are same, there is nothing to 'use against you'..

Hi Vulejov

I have tried Sonnys two outputshields, the one with 4627 sounds really good, but I ended up buying the discrete because it plays music and sounds amazing - I may admit since I don't finding pleasure in measuring the sound, I just enjoy listening to the music it makes :) - and I'm pretty sure you haven't tried that ;-)
 
Today we got the Graviton phonostage boards. Heavily delayed! [emoji21]

The pcb manufacturer print line i had ordered them at first, has closed its business so I had to find another manufacturer that could produce the board in short time.

We will assemble them tomorrow.

Sent from my iPhone using Tapatalk

No wonder printline closed, used them a couple of times for prototypes, but after my 2nd batch of significant substandard PCB's I gave up on them....

Now I use only PCBCART for my prototypes and sometime first series, they just work....