Cosmos APU a notch+LNA $70 to outperform APx555b for $30000

[IVX]

Is this option available now ? Have sent a mail to Sunny's gmail account. But maybe it ended up in spam.
Can't buy from Aliexpress. Same issue as others. VPN and switching site to English did not help. I reckon the site is looking at some locale setting of the browser and/or OS.

yes, why not, we just now discussed that option with Sunny, It will be available as the Assembly kit $99:
1) Cosmos APU PCBA not calibrated
2) Wooden box
3) Case extrusion
4) Front panel
5) rear panel
6) black silicone legs 4pcs
7) M3 screws 4pcs
8) black screws 8pcs
9) red silicone protector for the phantom power

 

[bambadoo]

Arrived today. Will probably test in a week or so... Was in Greece when I ordered. No problems there.

 

[RickRay]

@IVX When plugged into a USB charger the amber led on the back is flashing; is this normal?

 

[IVX]

@IVX When plugged into a USB charger the amber led on the back is flashing; is this normal?

This is the Cosmos APU thread, APU's LED doesn't blink.
Cosmos ADC and 9038S/D DACs are blinking according to their Fs(higher Fs, faster blinking).

 

[RickRay]

Yes, I have an APU and the LED on the back is blinking.

 

[RickRay]

any idea?

 

[IVX]

How did it happen? Just by the first plug a USB-C cable? Probably, is not enough current of the USB host.

 

[RickRay]

It is plugged into a Samsung fast charger directly to the wall and I tried another USB outlet on a surge protector, same issue. I plugged it into a battery and it is constant on. That was the problem.

 

[IVX]

How did it happen? Which USB it was plugged in the first time?
I asking because EACH unit is tested twice.
a) simply for the current consumption to detect the defective PCBA if any
b) during calibration. If PCBA isn't calibrated, anyway it is tested 2nd time
For these tests I use Xiaomi 5V 3A charger or the Hippo powerbank.
Please tell me:
a) is your APU assembled and tested version?
b) did you see ever a normal operation of your unit? Can you reproduce that again?

 

[RickRay]

It is assembled and tested version. The minute I plugged it into a powerbank it worked perfect. I plugged it into a different wall adapter the first time and it worked perfect also. Didn't work with Samsung fast charger or USB port located on power strip. Pretty sure you are correct, needs a high power USB connection.

 

[IVX]

APU may have some short inrush current, perhaps some USB chargers have oversensitive protection about that.

 

[RickRay]

Might be, not sure, but I found something that worked.

 

[IVX]

For the best H2 performance anyway, a power-bank is needed.

 

[RickRay]

Good information, I'll be sure to use one.

 

[IVX]

Oh, H2 at <-150db levels is a very tricky beast, any time you need to change the APU input phase(exchange IN+ vs IN-) to make sure the H2 is minimal.

 

[RickRay]

Hadn't thought of that, excellent information.

 

[IVX]

haha, if Cosmos ADC calibrating brings H2 to -150-155db, even unscrewing and screwing again the PCBA to the housing, may change H2 level 5-10db up.
Or tighter screw may do that as well. H2 it is about the symmetry, and <-150db it's about 1/30000000 and less..

 

[RickRay]

I knew it was about symatry, but hadn't thought about even the screws having an effect. At that level I understand that now.

 

[keantoken]

Do the ADC and DAC support universal USB protocol so they can be used with Linux?

 

[IVX]

Do the ADC and DAC support universal USB protocol so they can be used with Linux?

correct, this is UAC2 i.e. Wn10-11, Linux, Android, Mac os, iOS.