E1DA Cosmos ADC

[IVX]

IVX​

Do you have any plans to add SPDIF output to ADC (officialy or by diy expansion)? I saw some attempts here to add it, but probably no one succesed with it.

This is the SPDIF FW, I tested that with Cosmos ADCiso but it should be Ok with the original Cosmos ADC as well. The SPDIF output is routed to the MCLK pin of the PCB header, you can get +5V and GND over there and simply add TOSLINK optical output(in fact, only 74lvc buffer + bright-red LED).
The USB data transfer keeps working as well 44.1-768k, however, SPDIF will stop working >192k(it works but the frequency isn't standard so no one SPDIF receiver can get that).

 

[Bacek]

Thanks, and where I can find connector pins description? Tried to find one but I had no luck.

And maybe additional question. What is timeframe where ADCiso will be avaliable?
Never mind, stupid question. It's on aliexpreess.

 

[IVX]

E1DA Cosmos ADC

I've not done this yet and will wait for the isolator that should arrive any day. Then I'll do some experiments. If you have a spare laptop, you can use the spare laptop for the DAC, and the macbook for the ADC.

www.audiosciencereview.com

 

[BKDad]

Maybe a better solution for the IMD measurement would be a bandpass filter centered at 7 KHz. Sort of an inverted APU notch. The stop-band could be limited by resistors to be -30 dB from the peak at 7 KHz, kind of like how the notch is limited in the APU. That would minimize IMD in the ADC caused by the low frequency tone but still let you look closely at the IMD around the 7 KHz tone.

I'm not sure how much better that would be than the simple high pass filtering of the 60 Hz tone is, though.

OK, maybe the thing to do would be to make a PCB with an anti-alias filter on it and a switchable high pass filter, too. Easily equalized within REW.

 

[IVX]

SMPTE/DIN test includes the noise within BW.

 

[Bacek]

IVX,

Thank you, I was looking on old board with new one it's clear.

So last question. Sampling depth and frequency probably needs to be selected on PC driver settings. But will it work without PC then? Will settings stick after powering off/on?

 

[BKDad]

SMPTE/DIN test includes the noise within BW.

So, then, do something like AP might do.

Two notches, one at 60 Hz and one at 7 KHz to take out the tones and IMD, leaving just the noise. Then, a 7 KHz bandpass filter to measure the IMD by itself. Paste the two together for the SMPTE/DIN test. Lots of RF testing is done along those lines. I'm not sure if REW will do that in its present form or not.

Seems like a lot of trouble, though, at least for DIY guys building and testing preamps and amps. Your high pass filter solution probably is close enough. After all the distortion from the ADCiso is already pretty low.

 

[IVX]

IVX,

Thank you, I was looking on old board with new one it's clear.

So last question. Sampling depth and frequency probably needs to be selected on PC driver settings. But will it work without PC then? Will settings stick after powering off/on?

Without the host Cosmos ADC will start SPDIF operation as 24/48 every time it turns On.

 

[bbgma1234]

This is so interesting, because it kind of shows where the gap is between "class compatible", the idea of getting straight to the quality of the electronics not dependent on mass-production, and the need for custom drivers. It's not necessarily easy to tell digital components to do exactly what we want them to do. But, drivers can introduce the same technical hurdles that the digital electronics inside the gear.
Capacitors and op-amps to and from the actual converter, sample rates, and the potential for analog conversion before or after them, can all be messed up at the component level and also at the software level. Once you create even a small applet for controlling sample rate or anything else, you're now dealing with OS versions, driver conflicts, and hosts.
I personally still believe general things in the camp of ASIO are solutions that can be used for a separate standard than the "class compliant" "standards" .
I love reading this stuff.

 

[tatosa]

Hi guys,
I received the ADCiso device in December. HW version: ISO v1.1. Everything works as described, but the left channel LED never indicated anything. I switch to any mode (mono, stereo, overdrive) the LED is dark. The LED of the right channel indicates correctly. I don't know which FW version was in it when I got it. IVX says "always the latest", but it is not known if there was an update while the device was at the dealer. On the forum, IVX indicated that there is a problem with the operation of the LEDs and made a new FW available. I uploaded this, but there is no change. The display of the left channel still does not work. Anyone have an idea for a fix?
To IVX:
- it would be nice if the FW version could be requested, or I just don't know how.
- When is the self-developed measuring software expected?
- I would like information about the high impedance input prepared on the PCB. (components, circuit diagram, does the conductive strip need to be interrupted on the existing PCB)
Has anyone built it yet? What is the experience?
Thank you, Attila

 

[IVX]

Hi guys,
I received the ADCiso device in December. HW version: ISO v1.1. Everything works as described, but the left channel LED never indicated anything. I switch to any mode (mono, stereo, overdrive) the LED is dark. The LED of the right channel indicates correctly. I don't know which FW version was in it when I got it. IVX says "always the latest", but it is not known if there was an update while the device was at the dealer. On the forum, IVX indicated that there is a problem with the operation of the LEDs and made a new FW available. I uploaded this, but there is no change. The display of the left channel still does not work. Anyone have an idea for a fix?
To IVX:
- it would be nice if the FW version could be requested, or I just don't know how.
- When is the self-developed measuring software expected?
- I would like information about the high impedance input prepared on the PCB. (components, circuit diagram, does the conductive strip need to be interrupted on the existing PCB)
Has anyone built it yet? What is the experience?
Thank you, Attila

If you flashed the new FW with LED bugfix but LED is still not blinking, I believe the LED is dead(the RGB LED has 4 pins, one is GND, and it seems that pin is lost). So far I have no one case like this for ~1300pcs sold units but nothing is impossible. Sorry about that, pls contact the reseller.

 

[tatosa]

Thanks for the quick reply IVX.
Can I get information about the type of LED?

 

[IVX]

https://pt.aliexpress.com/item/1005006259411023.html?src=google&aff_fcid=e2503ed47a1b4c02b93ae641c2b10713-1706877453534-06260-UneMJZVf&aff_fsk=UneMJZVf&aff_platform=aaf&sk=UneMJZVf&aff_trace_key=e2503ed47a1b4c02b93ae641c2b10713-1706877453534-06260-UneMJZVf&terminal_id=7b4865745262402db1d00114a4f8a383&afSmartRedirect=y

 

[chuckt62]

@IVX, do you have a timeline for availability of more Grade 0 ADCs?

 

[staticV3]

@IVX, do you have a timeline for availability of more Grade 0 ADCs?

There's no timeline for the silicon lottery

 

[chuckt62]

Do they use different opamp?

 

[staticV3]

Do they use different opamp?

Same chips, just superior silicon.

How many Grade 0 ADCs IVX can make is out of his control.

 

[IVX]

yeah, a casino as is.

 

[chuckt62]

I had the last grade A version in cart on AliExpress, but someone else got it before I could checkout.

 

[IVX]

grade A is no problem, the rare is zero.