Symptoms of a SC ADC failure?

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TOL Asus soundcard with the CS5381 ADC, was taking beautiful measurements with a -130db noisefloor neglible added distortion.

Now the noise floor is -100db, and any slight AC input clips.

I know I didn't hit it with any DC but possibl accidentally 2-3VAC, I thought it had protection diodes.

Hate to buy a new card if this is a software issue.

Do the symptoms above sound familiar to anyone who had blown an ADC in a soundcard ?
 
ESD damage, do you wear a ESD strap and cotton coverall when playing with the boards?

Yea, and after all the playing and testing the components on the soundcard I decided it had to be software.

Removed all the drivers, reinstalled. And now everything is fine, this card takes great measurements for the price and I am a dumbA$$ for panicking and trying the basic step first :bawling:

But god I can't wait till the day we have a windows native 32/768 USB driver and a good low cost USB ADC device.

But by then USB will probably be obsolete.

Now is a terrible time to buy any soundcard if you look at Intel's archeticture plans, I think that's why I paniced :mad:
 
Probably the real THD+N is at around -105..107dB, and SNR unweighted at -115...-117dB not -130dB.
The cip itself has in the specs shown -110dB for THD+N and -120dB for DR (that is calculated at -60dB level).

At -1dB input level you cannot have better results for THD+N than the published ones: -97dB.

The analog front end can only decrease that number. It is a good ADC, but no ADC hits -130dB real live performance.
If you have anything "better" than that you should suspect a digital loop-back in digital domain inside the drivers (even if you think that you have a cable attached for loopback).
 
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Thanks Sonic, I didn't mean a standard NIST traceable audio weighted, guage R&R'd noise floor, just that it went up 30 db's which is a lot. You certainly know more about digital and its measurements than I do. I really don't use loopback or even the spdif of the card. Not scientific for an absolute number, just relative gauge, generally Art Legato - my best DAC- DUT-line-in of the card. I used an EMU0404 for years but it wasn't compatible with SandyBridge. So I got this Asus used for cheap when it became useless for the hometheater crowd with the hdmi out from ATI graphics cards. My thought is any soundcard-pci/pcie/usb/firewire won't work in a couple years as all those interfaces will be non-native with Haswell.

Here are some measurements from silentpc's review of the card. I've seen similar results at other reviews on the web.
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I get similar results as above, albleit with bumps at 60hz, 120hz.
 
What do you have, the DX? It's rated at -108dB at inputs by Asus (is not bad).

BTW, hot links to pics are not working, but I saw them.



Its the Asus HDAV1.3 (not the slim), it is quite similar to the newer Asus STX, but it had an HMDI passthru so the hometheater guys could get DTS-HD etc, now video cards do that so thats how I got it cheap used. I think it is quirky though. But I think as an ADC its pretty similar to the STX.


They claim that is an EMI shield. My cheap biostar motherboard has it sitting righ touching my HD6850 video card (bad situation) but for the money the Biostar is underated (its stable stable.)
 
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