ohm question and voltage

[sounds_explicit]

thinking im having a loose wire connection. sometimes my subs hit extremely hard and some days they hit soft. usually happens after i fiddle around with the wires. so im about to head out and re check everything make sure connections are tight.

but before i came nside few minutes ago i checked the connections on the amp and terminals for box.

checked the ohm reading just out of curiosity and both subs are not at a stable ohm reading. they are jumping up and down from 1.5-2.0 each one. they might hold a ohm of 1.5-1.7 for a second then jump around. its pretty windy out not sure if my subs are that broke in that the wind from outside is affecting my ohm reading while the trunk is popped.

2nd i want to check the rcas. is there a way to check them with a dmm? what should i set it to and what kind of voltage am i looking for. or does it matter on the pre out voltage of the head unit.

also i want to check what my readin is coming from the amp terminals to make sure the channels are also in good shape.

thanks

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[FML 10+ year member]

thinking im having a loose wire connection. sometimes my subs hit extremely hard and some days they hit soft. usually happens after i fiddle around with the wires. so im about to head out and re check everything make sure connections are tight.
but before i came nside few minutes ago i checked the connections on the amp and terminals for box.

checked the ohm reading just out of curiosity and both subs are not at a stable ohm reading. they are jumping up and down from 1.5-2.0 each one. they might hold a ohm of 1.5-1.7 for a second then jump around. its pretty windy out not sure if my subs are that broke in that the wind from outside is affecting my ohm reading while the trunk is popped.

2nd i want to check the rcas. is there a way to check them with a dmm? what should i set it to and what kind of voltage am i looking for. or does it matter on the pre out voltage of the head unit.

also i want to check what my readin is coming from the amp terminals to make sure the channels are also in good shape.

thanks

There's an answer to all this.

What impedance are your woofers? If 2 ohm, then you're fine. Even if you Have a top notch meter, a little variance is to be expected. Im at 1 ohm, and i have a bery high quality meter and i normally read between .9 and 1.1.

Secondly to test RCA's, set your meter to voltage. One lead goes on the center pin, the other on the shield (circle part) . Depends on your HU and what settings you have, but generally should be between 2 and 4 volts.

And unless you are super concerned about dialing in gain or getting a clamp test, testing the amps output terminals wont do much for you. If everything is working, its safe to say its fine.

The fact that you think you get different volume at different times can mean a number of other things.

A bit more info on your setup? Including vehicle

 

[sounds_explicit]

they are dual 4 ohm wired to 1 ohm and im seeing 1.5-2 ohms fluctuate on both subs, wait im a idiot 2 2ohm subs wired is 1 ohm so never mind that lol.

and ill check the rcas here in a few minutes.

and its not just max volume or somethng sometimes the low end volume hits hard like it should when i adjust setting on the headunit( sub level) and sometimes everything is softer sounding.

i have a few songs i listen to that i know how hard they pound on and sometimes they pound hard and the next day its like a completely different system.

2 ab xr12d4's 3000 watt mono block (maybe putting out 800 into each sub)

big 3 upgrade

2 batteries

zero gauge wiring

08 charger

 

[adulbrich 5,000+ posts]

2 dual 2's can't be wired to 1 ohm.

 

[sounds_explicit]

i meant 2 dual 4 ohm subs wired to 2 ohms each is 1 at amp. sorry if i confused you

they are dual 4 ohm subs wired to 2 each and 1 at the amp.

 

[adulbrich 5,000+ posts]

Alright, sounds good

 

[sounds_explicit]

Alright, sounds good

and i just checked the rcas but im not getting any type of voltage reading. i have a dmm with 5 diff voltage settings.

what should i use to check

200m

2

20

200

600

 

[adulbrich 5,000+ posts]

Try 200m, 2, and 20.

200 and 600 are wayyyy too high.

 

[sounds_explicit]

Try 200m, 2, and 20.
200 and 600 are wayyyy too high.

shield and prong on same rca? or shield one rca prong on other rca?

 

[adulbrich 5,000+ posts]

Same RCA

 

[sounds_explicit]

Same RCA

ok well the rca cables read 4 volts, well one of them does at least.

are they supposed to both read a voltage?

or only one out of the two?

 

[adulbrich 5,000+ posts]

ok well the rca cables read 4 volts, well one of them does at least.are they supposed to both read a voltage?

or only one out of the two?

Both should read a voltage. Swap RCA's and see if the problem persists. If it does, may be a problem with HU or amp.

 

[sounds_explicit]

Both should read a voltage. Swap RCA's and see if the problem persists. If it does, may be a problem with HU or amp.

ok. ill recheck the rcas tomarrow and if only 1 reads a voltage ill swap them out.

if the problem persists after new rcas, can i check out pre outs on the head unit the same way on the sub pre outs? to see if they both are giving a voltage readout?

and if they are is there a way to check the amp then itself?

 

[adulbrich 5,000+ posts]

Touch leads directly to the sub out on the head-unit to rule out RCA's and everything after them. If it doesn't read a voltage here, nothing down the line is an issue.

If the RCA's read a voltage, it's probably your amp.

 

[sounds_explicit]

ok thanks ill recheck back tomarrow.

gotta run to store get some popcorn and big bulps for this justin beiber roast tonight!

haha