Setting gain with DMM

[DBfan187 5,000+ posts]

what is your volume level?

 

[GnFnRs 10+ year member]

this is puzzling. the formula for finding power is..voltage squared x resistance..according to this my treo 1500.1's would have to put out about 56.6 volts to each sub to do 3200 watts.

when i set my gains with a fluke 177 dmm, i was at 3/4 volume and set the ac voltage at 78v on each sub..this was where i got .02 volts dc so i stopped..so as not to clip the amps....well if ya do the math,thats 6084..and i know there is noway these amps put out that kinda power. what gives??

 

[DBfan187 5,000+ posts]

you can't detect clipping with a dmm, need an oscope.

 

[GnFnRs 10+ year member]

you can tell when the dc voltage is more than the subs can handle lol i use an o scope on the input side to check rca voltages. but dmm works fine for everyday systems. not trying to wring every .1db out of her.

the ssx15's have pounded at that voltage for 2 and a half years now.and that didn't help me with my question of how i got that much voltage? lol

seriously it's got mescratching my head

 

[DBfan187 5,000+ posts]

clipping isn't DC, it's AC.

If you have an oscope, you should use it to set your gains.

 

[DBfan187 5,000+ posts]

your voltage isn't going to magically stop when your amp clips, it'll keep going up. That's why you got those reads, that's why a dmm can't detect clipping, and that's why you should use an oscope.

 

[dman4486 5,000+ posts]

clipping isn't DC, it's AC.
If you have an oscope, you should use it to set your gains.

so um....how much can i buy one for, or where in the upstate SC can i borrow one?

 

[DBfan187 5,000+ posts]

so um....how much can i buy one for, or where in the upstate SC can i borrow one?

http://cgi.ebay.com/Velleman-HPS10SE-2MHz-Personal-Scope-10MS-s-NEW_W0QQitemZ330206417243QQihZ014QQcategoryZ104247QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

[darkhunter139 10+ year member]

http://cgi.ebay.com/Velleman-HPS10SE-2MHz-Personal-Scope-10MS-s-NEW_W0QQitemZ330206417243QQihZ014QQcategoryZ104247QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Yea, thats more then I paid for my amp lol

As long as I measure the AC voltage with a DMM and dont set it higher then my sub I should be safe right?

 

[luvinthebass 5,000+ posts]

that hte one you got Mike?

 

[DBfan187 5,000+ posts]

Yea, thats more then I paid for my amp lol
As long as I measure the AC voltage with a DMM and dont set it higher then my sub I should be safe right?

sure

that hte one you got Mike?

yes, though it broke when I left it out in the cold for a week. LCD's don't like cold weather. //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif I have to get a new one.

 

[luvinthebass 5,000+ posts]

sureyes, though it broke when I left it out in the cold for a week. LCD's don't like cold weather. //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif I have to get a new one.

that sucks man, i left my dmm out in my car for a week the LCD worked but it was really slow.

the ones on amazon for o-scopes are way to high.

 

[darkhunter139 10+ year member]

I just picked up a DMM that was on sale for $12 at sears (its regular 30 seems pretty nice)

I am going to get the DC measurement in about an hour

 

[darkhunter139 10+ year member]

Alright I got a ton of questions here

Ok first my head unit has a thing that says woofer then you can change that from 0-9 when I put it on 0 the DMM doesnt get a reading so I turned it to 5 and set my voltage to 31.3 with that is that the best number to put it on or should I turn the woofer all the way to 9?

another thing

I have this thing called Circle surround which puts tons more bass into the speakers and you can adjust how much bass you want in the fronts and rears. When I do this set my rears and fronts true bass to 3 and the woofer to 5 I get about 6 volts less on my DMM. Should I tune my system to the Circle surround option or what?

 

[jeremiah 10+ year member]

how do you know what ohm loud you are testing at if the sub is not hooked up?