New DIY DAC, some thoughts, ESS or AKM or staying true to the old school

[diyiggy]

also have a look to ES9312 with the self calibration option.

I would have a look to the 9027Pro too in QFP package... easier to solder, hardware mode okay. double proce vs 9039Q2M

 

[MarcelvdG]

Output impedance is 380 ohms BUT +/- 15%. Hope that it not between the channels in the same chip but just different series of bunch... 🙁

You can count on that. The spread between components on the same chip is always much smaller than between components on different chips, especially when those different chips are from different batches.

 

[batteryman]

Still, it seems like quality 1794 dac kits are liked a lot by a lot of people, but the good kits cost more than 200 Euros. One example: https://audio-creativeshop.nl/product/dddac-1794-mk3-module/ ...only € 458,68 (€ 555,00 incl. VAT). (power supply kit available at extra cost)

Yet, for some reason there isn't so much interest Marcel's RTZ dac. Maybe some change on that when a final most recommended output stage is settled on. However, like all things people spend money on, there has to be a compelling story, and there have to be enough in the way of positive reviews.

I bought a dual 1794 kit for the usual source and I do like what I am hearing. (I bought the version with just the dacs fitted, and no opamps so I could use my differential to se IV transformers)

 

[grunf]

These regulators are not best choice for ES9039Q2M because IC consuming less current.
Even VDD is internaly suplied... And specifies trough the AVDD consumption datas.
.
The best way (and previous models of ES like that way) is Vref ciruit for 3.3V with AD797 which can supply up to 50mA
way more than DAC IC need, 24 mA cca.

Well, I did some tests with very small loads, say DIR9001 whose current does not exceed 10mA. For that battle I used ADP7118, ADM7150 and Walt's shunt set to about 60mA. The shunt is completely SMD with a total dissipation of about 300mW which is not much at all.Then it happened to me for the first time that in the power supply with a digital scope I saw a straight line, a clean DC signal, completely clean, I could not believe it, I checked the scope, the probe but I could not see any high frequency artifacts specific to digital circuits.

 

[Zoran]

and Walt's shunt set to about 60mA.

That is another story ofcourse - because in that case regulator supplies more current device + shunt.
And should be compare what working better in sonic terms and measurements.
(Essential for the shunt reg is to find very low esr C at the output. to keep shunt very low impedance power source.)
.
But the Circuit for reference voltage (with AD797) does very good job. Also super clean I tried with another ESS ES9008 dac long time ago.

 

[Zoran]

It shoud be tested with very simple PS just one single 3.3V (almost worse case regulator).
In nardware mode, very simple schematic, with adapter DIP pcb.
to see how it behaves. It is one afternoon job.
.
Then, after listening tests, basic measurements, optionaly exchanging IV stages
go for design a complicated PCB?
.

 

[TNT]

... scopes are still(?) 8bit so.... well, it was a long time ago we stopped measuring voltage sources quality with a scope. Now we use 24 bit sound cards... just saying...

//

 

[Drbulj]

. scopes are still(?) 8bit so.... well, it was a long time ago we stopped measuring voltage sources quality with a scope. Now we use 24 bit sound cards... just saying...

And what sampling rate scopes use? Sound card is up to its best useful to 90-sh kHz, scopes go to MHz

 

[TNT]

BW doesn't matter really if you cant see the waveform....

//