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How do I measure DAC output voltage?

OP1M.DR3M

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Hi all,

I'd like to measure the output voltage of my SMSL M500 DAC at various volume levels via the XLR and RCA outputs. How do I go about doing this? Will my multimeter (below) suffice?

Your shared knowledge, as always, is much appreciated :)

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There might be a issue with this specific multimeter you pictured. The 200 volt AC range might not have the resolution nor the sensitivity for measuring the lower voltages present at the RCA and XLR terminals. It might work or it might not be very accurate. Do you have another multimeter with a lower range for the volts AC??
 
There might be a issue with this specific multimeter you pictured. The 200 volt AC range might not have the resolution nor the sensitivity for measuring the lower voltages present at the RCA and XLR terminals. It might work or it might not be very accurate. Do you have another multimeter with a lower range for the volts AC??

I do not but can order one on Amazon real quick. Am I looking for something that will go down to the 20 range?
 
Yes, it might do. I would use a 200 hz tone for measuring. Your meter is said to have 40 hz to 400 hz frequency response. This isn't an optimum meter for this use. Still as you have it on hand, measure and see what results you get. You can get a different meter later. Or perhaps borrow one.

The lowest setting on your meter for AC voltage is 200 volts. So the levels you'll be looking at are mostly than than 5 volts. Your manual lists 1.2% accuracy over 10 volts. So the measures may be somewhat inaccurate.

Quite simply select AC 200 volts on your meter. Connect the red lead to the center pin of an RCA cable and the black lead to the outer grounded shell of the RCA jack. Set volume to max and read voltage. You really don't need to read lower volume levels generally speaking.

For XLR connect the red and black leads across pins 2 and 3.
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Another view.
XLR-Wiring-Standard-3-pin.jpg
 
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Yes, it might do. I would use a 200 hz tone for measuring. Your meter is said to have 40 hz to 400 hz frequency response. This isn't an optimum meter for this use. Still as you have it on hand, measure and see what results you get. You can get a different meter later. Or perhaps borrow one.

The lowest setting on your meter for AC voltage is 200 volts. So the levels you'll be looking at are mostly than than 5 volts. Your manual lists 1.2% accuracy over 10 volts. So the measures may be somewhat inaccurate.

Quite simply select AC 200 volts on your meter. Connect the red lead to the center pin of an RCA cable and the black lead to the outer grounded shell of the RCA jack. Set volume to max and read voltage. You really don't need to read lower volume levels generally speaking.

For XLR connect the red and black leads across pins 2 and 3.
View attachment 71276
Thanks for this! Should I look up "200hz tone" on youtube or perhaps use a tone generator site like this? https://www.szynalski.com/tone-generator/
 
Will my multimeter (below) suffice?

This one won't. You will need one that measures AC voltages with a range as low as 2VAC
The shown meter will be inaccurate for sure and will certainly show an incorrect reading.
 
This one won't. You will need one that measures AC voltages with a range as low as 2VAC
The shown meter will be inaccurate for sure and will certainly show an incorrect reading.

Ok, this one on Amazon will go down to 2v.. frequency is "20khz", this should work ok?
Screen Shot 2020-06-29 at 10.24.47 PM.png
 
Ok, this one on Amazon will go down to 2v.. frequency is "20khz", this should work ok?View attachment 71285
Yeah, it should do what you need. I always distrust these inexpensive meters from China on Amazon until I can compare them to something good. OTOH, I've had hands on a few of them, and they generally are pretty good. So while it is no Fluke, it probably will do just fine for your purposes.
 
Yeah, it should do what you need. I always distrust these inexpensive meters from China on Amazon until I can compare them to something good. OTOH, I've had hands on a few of them, and they generally are pretty good. So while it is no Fluke, it probably will do just fine for your purposes.

Found this Fluke for a reasonable $46 on Amazon https://www.amazon.com/Fluke-101-Mu...ywords=fluke+multimeter&qid=1593495847&sr=8-7 Worth it?

Specs on Fluke's site shows down to 600mV range but frequency is 10Hz-100kHz. Does this have anything to do with the test tone I'd play through the DAC?

Screen Shot 2020-06-29 at 10.49.10 PM.png
Screen Shot 2020-06-29 at 10.50.01 PM.png
 
Oh wait, you said to 200hz tone which is well within range. Although I have no idea if that is related to that spec as far multimeters are concerned.
 
Oh wait, you said to 200hz tone which is well within range. Although I have no idea if that is related to that spec as far multimeters are concerned.
Well 200 hz was based upon the response of your meter in the 1st post. In these others with plenty of response bandwith I'd just use the more or less standard 1 khz. 200 hz would do just fine however.

Many meters even cheap ones will do 400 or 500 hz because some military generator systems run at 400 hz.
 
Found this Fluke for a reasonable $46 on Amazon https://www.amazon.com/Fluke-101-Mu...ywords=fluke+multimeter&qid=1593495847&sr=8-7 Worth it?

Specs on Fluke's site shows down to 600mV range but frequency is 10Hz-100kHz. Does this have anything to do with the test tone I'd play through the DAC?

View attachment 71294View attachment 71296
Honestly I'd get the other one you had in mind. Does more for you in case it is useful. The Crenova model.

BTW, the above has a frequency counter which is a different thing than the response of AC voltage.
 
Well 200 hz was based upon the response of your meter in the 1st post.

Ohh.. is it related to my multimeter only going down to 200v AC?..
 
Found this Fluke for a reasonable $46 on Amazon https://www.amazon.com/Fluke-101-Mu...ywords=fluke+multimeter&qid=1593495847&sr=8-7 Worth it?

Specs on Fluke's site shows down to 600mV range but frequency is 10Hz-100kHz. Does this have anything to do with the test tone I'd play through the DAC?

View attachment 71294View attachment 71296
The 100 kHz range is for frequency measurements. For AC voltage, the specified range is 40–500 Hz.

Ok, this one on Amazon will go down to 2v.. frequency is "20khz", this should work ok?View attachment 71285
Again, the figure you're highlighting is for frequency measurements. The frequency range for AC voltage isn't specified.

If you're willing to spend a little more, you could get a Fluke 115 or similar. It does true RMS voltage up to 1 kHz. The Fluke 287/289 have a true-RMS bandwidth of 100 kHz, but they are rather expensive (and very nice).
 
Reviving this old thread as I'm struggling with the same thing. I'm trying to measure xlr output from my SMSL SU-9 DAC at different volume levels so I can properly match volume with different components. I'm using the EEVblog BM235 seen here https://images-na.ssl-images-amazon.com/images/I/81a+hXNwWsL._SL1500_.jpg

I have it set on Auto V LoZ, I have dac on, at full volume and playing 1000hz test tone. I have short 1 foot xlr plugged into the left output of the dac, and the male xlr end in front of me for measuring. I tested on AA battery to make sure the meter is working, and it measures 1.6v automatically and consistently. When I connect the leads to pin 2 and 3 on the xlr, I don't get any response on the multimeter, it doesn't show any voltage, and it doesn't beep like it should when it makes a reading. I plugged in the right xlr to amp and speakers so i know for sure the test tone is playing out of the dac. I also tried with 200hz test tone and got no measurement with that either.

Any advice or other things I should check for would really be appreciated.
 
Reviving this old thread as I'm struggling with the same thing. I'm trying to measure xlr output from my SMSL SU-9 DAC at different volume levels so I can properly match volume with different components. I'm using the EEVblog BM235 seen here https://images-na.ssl-images-amazon.com/images/I/81a+hXNwWsL._SL1500_.jpg

I have it set on Auto V LoZ, I have dac on, at full volume and playing 1000hz test tone. I have short 1 foot xlr plugged into the left output of the dac, and the male xlr end in front of me for measuring. I tested on AA battery to make sure the meter is working, and it measures 1.6v automatically and consistently. When I connect the leads to pin 2 and 3 on the xlr, I don't get any response on the multimeter, it doesn't show any voltage, and it doesn't beep like it should when it makes a reading. I plugged in the right xlr to amp and speakers so i know for sure the test tone is playing out of the dac. I also tried with 200hz test tone and got no measurement with that either.

Any advice or other things I should check for would really be appreciated.
Try setting it like the picture of your device in the link pointing to VFD.

The manual says the auto input you have chosen won't work until it sees more than one volt. So you may be feeding it less than one volt. For instance a 4 volt max output if playing a -20 db test signal would only be .4 volts and your auto-loZ input would ignore that.

I think even in voltage for VFD it will auto-range, but according to the manual you can manually select level and the lowest most sensitive setting on this meter will be for 6 volts max. Which should be fine for your purposes.
 
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Try setting it like the picture of your device in the link. Also see if you have any voltage between pin 1 and pin 2 or pin 3.

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.
 
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