How do I measure DAC output voltage?

[Blumlein 88]

I set it like the picture, then changed it to AC (wavy line). I still get no readings between pin 2 and 3, or pins 1 and 2. Between pins 1 and 3 I do get a reading, but it's showing only .5v. This is with 200hz sine wave playing.

What signal are you using for output. You may well only be getting .5 volts out. If you change volume does that voltage change? Of course you should be getting a reading between pin 2 and 3 normally.

 

[Blumlein 88]

You might turn the volume all the way up. That DAC should put out over 5 volts. And where are you getting the 200 hz signal from? Is it a 0 dbFS signal or one of lower value.

 

[cursive]

You might turn the volume all the way up. That DAC should put out over 5 volts. And where are you getting the 200 hz signal from? Is it a 0 dbFS signal or one of lower value.

First off, thanks for all your help Blumlein 88.

Ok, so making progress. First issue, I was an idiot and didn't realize your diagram for pin layout was from the solder side, so I was measuring from the wrong pins, duh. The pins I'm getting voltage on are pins 2 and 3.

I used this site https://www.wavtones.com/functiongenerator.php to create a 0dbFS tone, and put it on loop on foobar. I did a 60hz tone at 0dbFS, and I'm getting 1.8v between pins 2 and 3. The SU-9 should be 5.3 volts at full volume, so not sure if I should be using a different tone, or a sweep, or something like that.

Oh and i chose 60 because of the multimeter manual.

 

[Blumlein 88]

First off, thanks for all your help Blumlein 88.

Ok, so making progress. First issue, I was an idiot and didn't realize your diagram for pin layout was from the solder side, so I was measuring from the wrong pins, duh. The pins I'm getting voltage on are pins 2 and 3.

I used this site https://www.wavtones.com/functiongenerator.php to create a 0dbFS tone, and put it on loop on foobar. I did a 60hz tone at 0dbFS, and I'm getting 1.8v between pins 2 and 3. The SU-9 should be 5.3 volts at full volume, so not sure if I should be using a different tone, or a sweep, or something like that.

Oh and i chose 60 because of the multimeter manual.
View attachment 112338

I don't know why you wouldn't get a higher reading either. From your specs you could go ahead and use a higher frequency at least up to 440 hz. While it might be slightly inaccurate it should be consistent and no problem to compare output levels of two different devices. For instance maybe it reads 2% high at 440 hz, it would read 2% high with both devices and matching would still be good.

Have you tried the RCA outputs to see what voltages you get there?

 

[cursive]

I don't know why you wouldn't get a higher reading either. From your specs you could go ahead and use a higher frequency at least up to 440 hz. While it might be slightly inaccurate it should be consistent and no problem to compare output levels of two different devices. For instance maybe it reads 2% high at 440 hz, it would read 2% high with both devices and matching would still be good.

Have you tried the RCA outputs to see what voltages you get there?

Finally got it! Thanks so much Blumlein. Again, it was user error, when i reinstalled foobar2000 it enabled replaygain, and was stepping down the gain of the test tone automatically. I found a tidal playlist with test tones, 1khz @ 0db, and now @ 99 volume I'm getting 5.144v which is right in line with the spec. 95 volume on the SU-9 to get exactly 4.0v, and 90 on the dac to get exactly 3.0v. That was what I was trying to figure out, so now I'm set.

Also for anyone else who uses Tidal - https://tidal.com/browse/album/29581889 Nice test tone playlist with a lot of useful tones.