how to use the Digital Multi-Meter (DMM)

[M@nJo 10+ year member]

ok, so i purchased one from walmart for $18. it came with two wires (one black/one red) and now where do i plug these into? im trying to adjust my subsonic filter but dont know which wire goes into which. theirs 3 slots, V/Ma, max DC/AC, and max 10a/max 500a dc/ac. which one does the red/black go into when measuring the ssf?

and for future ref...how do i check my car battery and what else can i do with this unit?//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

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[SSS 18734 5,000+ posts]

how are you measuring the subsonic filter with a DMM?

 

[M@nJo 10+ year member]

got this from another member here:

To properly set the subsonic filter:

1) SSF = Tuning*0.75 (i.e. 38*0.75 = 28.5 Hz)

2) Burn a test tone CD with that frequency (28.5 Hz) or round up to the nearest integer (29 Hz)

3) Turn the SSF off or all the way down (full counter-clockwise).

4) Disconnect all speakers from the amplifier

5) Screw in the multimeter leads and set it to AC Voltage

6) Insert the test tone CD, play, and repeat the track (28.5 Hz or 29 Hz)

7) Turn the volume up to normal listening volume

8) Note the voltage reading on the multimeter and multiply that number by 0.707 (i.e. 20*0.707 = 14.142 volts) ... This is your target voltage ...

9) Keeping the volume level the same, turn the SSF on and slowly turn the the SSF up until you reach the target voltage.

 

[tplaya07 10+ year member]

Just out of curiosity, and Im not trying to sound like an *** or anything. How much of a range do you have for the SSF? Usually they are only about a 20-30Hz range, and it shouldn't be too hard to guesstimate within a couple Hz of your desired setting. It does not have to be exact, as the size of your crossover slope will come into play as well...as to how quickly it will diminish anything under your desired setting.

 

[M@nJo 10+ year member]

the highest it goes on my amp is 35hz on the ssf.

 

[M@nJo 10+ year member]

bump for help using the dmm