E1DA Cosmos ADC

[SchwarzeWolke]

Just a quick question to @IVX:
Can I use the Cosmos with Win10 without any driver? Does this work as an USB 2.0 audio device? I might use this with a company laptop and can't install anything.

 

[mansr]

Just a quick question to @IVX:
Can I use the Cosmos with Win10 without any driver? Does this work as an USB 2.0 audio device? I might use this with a company laptop and can't install anything.

Yes, the USB Audio Class drivers in Win 10 work. You won't be able to update the firmware or use the tweak app, though.

 

[MCH]

BTW, I made the second proto of the Cosmos Scaler preamp, a relatively simple device with the gain knob 0..20db to provide low noise and distortions high impedance input preamp for the Cosmos ADC. Input and output range is up to 10Vrms, 2 channels, USB-C powered, 20kOhm input impedance balanced and 10 unbalanced. This is an instrumental amplifier that uses OPA1612 and 4 relays to get 16 steps of the gain with minimal distortions. The device contains RGB LEDs(the same as Cosmos ADC has) to help you evaluate the output level. Red LED indicates the overdrive condition(10Vrms), green one 4.5Vrms, and blue 1.7Vrms(i.e. lower range of Cosmos ADC). The device is my reaction to complains that Cosmos ADC can not correctly measure a junk-level DACs with nonbuffered 1kOhms output impedance, and also for vinyl-rip enthusiasts to lift up turntable's output level to 3-5Vrms with maximum fidelity. The last reason is I like such knobs and your money
View attachment 168511View attachment 168533

Ever thought of a phono stage (riaa implemented)/ADC?

 

[Martyreasoner]

Ever thought of a phono stage (riaa implemented)/ADC?

With AES out

 

[IVX]

I just prepared and tested 100pcs thermostat boards, tomorrow Sunny will update the shop.

 

[IVX]

To get the PCBA of Cosmos ADC out need to screw out 6 screws. 4pcs at the front panel, and 2pcs on the bottom, near to the rear panel.
Next please follow that scenario:

Glue the thermostat board at ES9822 chip by Pattex, "502"- cyanoacrylate adhesive super glue etc.

 

[trl]

Thank you for the updates Ivan!

How much better the SINAD will become after performing this mod, please? Let's compare with a 20C room.

 

[IVX]

hard to say but better so that's enough reason to add that tiny PCBA Member Hee, from Korea, did compare THD@23C and 30C, you can use search on ASR forum to see the result.

 

[Atanasi]

I just prepared and tested 100pcs thermostat boards, tomorrow Sunny will update the shop.

How does this communicate the measurements with the ADC?

 

[staticV3]

How does this communicate the measurements with the ADC?

The Thermostat board simply keeps the ES9822 chip at a constant 50°C. It is a closed system. No communication between thermostat and Cosmos takes place.

 

[trl]

Member Hee, from Korea, did compare THD@23C and 30C, you can use search on ASR forum to see the result.

If it's https://www.audiosciencereview.com/forum/index.php?threads/e1da-cosmos-adc.27038/post-986831 then it needs remeasured, as it shows a SINAD of 123 dB.

 

[MCH]

I am very curious, can someone elaborate on what is the effect of temperature in the performance? I mean the physical reason, not the results themselves.

 

[IVX]

the reason is the properties of a polyresistors inside of ES9822.

 

[IVX]

If it's https://www.audiosciencereview.com/forum/index.php?threads/e1da-cosmos-adc.27038/post-986831 then it needs remeasured, as it shows a SINAD of 123 dB.

1) I think the FFT SW he used there isn't correctly calculates THD+N
2) the 3rd harmonic at -130db, I don't think if at such level Cosmos ADC 3rd harmonic will dominate at 23C in Hee's room

 

[MCH]

the reason is the properties of a polyresistors inside of ES9822.

So the value of the resistance of those polyresistors reaches an optimun at the temperature the heater brings the IC. Ok thanks.

 

[IVX]

rather the linearity of these resistors has an optimum at the particular temperature.

 

[pkane]

1) I think the FFT SW he used there isn't correctly calculates THD+N
2) the 3rd harmonic at -130db, I don't think if at such level Cosmos ADC 3rd harmonic will dominate at 23C in Hee's room

Mr. @Hee should try this with the latest release of Multitone (1.0.12) as that fixed a scaling issue that affected harmonic amplitude calculation.

 

[IVX]

Mr. @Hee should try this with the latest release of Multitone (1.0.12) as that fixed a scaling issue that affected harmonic amplitude calculation.

Yes, probably, I personally like to see one more free FFT app that will be able to measure audio and match to AP analyzers. So our list of recommended FFT will contain Arta, REW, and your Multitone.

 

[Hee]

I will measure it again with rew, mutitone, and arta on Monday.
I haven't bought an oven yet, but I'll try to change the temperature in more detail.
However, the 2nd and 3rd harmonics of the topping e50 seem to be worse than the specification of the cosmos adc.

 

[pkane]

Is there an AP IMD sweep for Cosmos ADC available? SMPTE 60Hz/7kHz 4:1?

I've done one using RME ADI-2 Pro FS as the source using my Multitone app and it shows a bit of the infamous IMD hump. Would like to confirm if this is the case with a better source: