Which DMM?

[ejschultz 10+ year member]

THats what I thought too..? My cheapo walmart one will measure the AC voltage from a 1khz tone, so I figured all of them would.

It measures it, but how accurately?

 

[Digital Designs 10+ year member]

It measures it, but how accurately?

No clue. It could be way off for all I know. I was just doing it messing around to see the voltage change on different tones //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif Yeah, I was bored.

 

[ejschultz 10+ year member]

No clue. It could be way off for all I know. I was just doing it messing around to see the voltage change on different tones //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif Yeah, I was bored.

See, if I do this, I want to do it right. I just want to find out if the frequency range matters for the test tone that I'm going to be using.

 

[ejschultz 10+ year member]

Okay, I'm going to bite the bullet and buy the Mastech MS8268. If anyone has anything negative about it, let me know. I'm going to be doing it in 5 minutes so speak now or forever hold your peace. I'm not going to be happy until I get one that has the frequency range I'm looking for.

 

[BassAddictJ 5,000+ posts]

i say do it by ear....

you're worried about accuracy but you're not clamping it. I say buy any reasonable priced meter that is supposed to work in that freq range, tune it to whatever voltage you want, then readjust the gain by ear until it sounds great

 

[smoka 10+ year member]

Ya, they get less accurate with the higher freqs. To read AC the dmm measures the peak of the sine wave, so the higher the freq the harder it is to read the peaks.

Why not just use a lower freq? I don't see any difference setting your gains at 400hz or 1khz?

 

[smoka 10+ year member]

Just borrow an Oscope from school and do it right?

 

[ejschultz 10+ year member]

i say do it by ear....
you're worried about accuracy but you're not clamping it. I say buy any reasonable priced meter that is supposed to work in that freq range, tune it to whatever voltage you want, then readjust the gain by ear until it sounds great

So the frequency does matter then. I'm probably going to buy the Mastech. It's the lowest priced one that has that frequency range and the brand makes some higher end meters as well. The specs on it are really similar to the lower end Fluke meters.

 

[ejschultz 10+ year member]

Ya, they get less accurate with the higher freqs. To read AC the dmm measures the peak of the sine wave, so the higher the freq the harder it is to read the peaks.
Why not just use a lower freq? I don't see any difference setting your gains at 400hz or 1khz?

I was told to do it at 1 kHz. I don't know why nor do I know if any other frequencies would do. I've never set gains using a DMM before.

Just borrow an Oscope from school and do it right?

Haha, we've got a bunch of new ones that they'd never let anyone borrow and the old ones are huge. I also highly doubt they'd let me use one of them either, if it would even work properly. You gotta love Purdue Calumet for that one.

 

[ejschultz 10+ year member]

So new question (the old one is still up too). Would using a lower frequency, ie. 400 Hz, be okay for setting the 4 channel amp or is it still better to use something a little higher like 1 kHz?

 

[ejschultz 10+ year member]

Okay, I'm buying it. No turning back. I'll use maybe an 1 kHz test tone then double check the readings with about an 800 Hz and a 400 Hz. I guess they should all be the same readings. I'd like to have the better meter for the future anyways.

 

[ejschultz 10+ year member]

Okay, not that anyone is responding to me babbling anymore, I just bought the Mastech and I'm returning the Craftsman tomorrow. Hopefully the Mastech comes in within the next week and a half. Lastly, does it matter on the frequency I use for the 4 channel amp?

 

[Digital Designs 10+ year member]

Okay, not that anyone is responding to me babbling anymore, I just bought the Mastech and I'm returning the Craftsman tomorrow. Hopefully the Mastech comes in within the next week and a half. Lastly, does it matter on the frequency I use for the 4 channel amp?

Why not test the Craftsman and see if it gives you the same reading? Then if it does, you know the craftsman is fine and you can get your money back for the more expensive one instead.

 

[ejschultz 10+ year member]

Why not test the Craftsman and see if it gives you the same reading? Then if it does, you know the craftsman is fine and you can get your money back for the more expensive one instead.

Although it's not a bad idea, the Mastech is a higher quality (spec wise) than the Craftsman. I'd rather have the better one. It's only like $20 more for more than double the accuracy at more than double the frequency. It's got pretty much the same specs as a Fluke.

 

[photocrazy8 10+ year member]

You can get a pretty cheap o-scope for $150... oh yea... FLUKE ftw!!!