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TurboDiesel 07-18-2011 07:17 PM

sub/amp problem
Hey so i have been having this problem with my subs for a couple weeks now and it is quite irritating

i love these subs but lately they have been pissin me off lol

so what happens is ill be drivin around and within a couple minutes the bass gets cut by half...then eventually will go back to normal then do the same thing again.

my friend told me that the amp is "clipping" which i read up on and it said u need to turn the gain down and the ohm load up?

so i turned the gain down, even tho it was already set to "normal" and turned something else up to get the bass back.

how do u change the ohm load?
or how would i fix this?

is this a sign of my amp or fuses going?

im running 2-alpine type R , with a alpine m1000 amp [1000w mono]
had them alittle over a year and they have been amazing with absolutely no problems since i bought them

thanks for the help!

remmy 07-18-2011 07:39 PM

Re: sub/amp problem
Ohm configuration is not done by adjusting a knob. Your subs may be configured at 1ohm and is probably finally killing your amp. Many people make this mistake. You need to do a different configuration. Google subwoofer wiring patterns to make sure you have or can get it right.

What is equally important is to find out what ohms your sub are at to begin with. The Alpine Type R can be bought with a DVC 2ohm or 4ohm.

Se7endust1 07-19-2011 05:16 AM

Re: sub/amp problem
usually if running at too low of an ohm, the amp will work for a few minutes, then fry itself. The fact that it goes back to normal volume after a while leads me to believe that isn't the case. I'd recommend swapping out your RCA cables that connect your head unit to the amp. Pulling the left or right plug while normal use can create a similar effect of "losing half" of the bass. If you swap out the RCAs and the problem still remains, it could be an output on the deck, or a bad solder joint on the amp causing it to not get full signal 100% of the time.

also remmy is correct, you need to hook up an ohm meter to the + and - that are going to the amp (while being disconnected from the outputs on the amp) and see what the values are that it's spitting out. I would also leave "that other knob" completely probably cranked up the bass boost on the amp. that's prob one the top killers of subs out there.

remmy 07-19-2011 06:55 AM

Re: sub/amp problem
^ like se7en said, turn that bass boost off. I wish it didn't exist on amps. They kill more subs thatn anything else because its only adding a nasty amount of harmonic distortion. Kind of like the Alpine "Media Xpander". It's all junk and just left off.

TurboDiesel 07-19-2011 07:32 AM

Re: sub/amp problem
allright well i know nothing about subs but i will give it a try
they were installed by futureshop and worked great for about 2 months and now do it

i might add that i do have a capacitor if that changes anything?
and i am hooked up to my stock deck with a line level converter.

so i would have to run new RCA cables thru the car?

and yes i will turn down the other knob when i get into the truck this morning lol
hate running subs but havin like no bass..

remmy 07-19-2011 08:34 AM

Re: sub/amp problem
Lol, that adds a whole lot more to possibly be a problem. The capacitor could be failing and the inverter sounds like a classic case that it's dying or pending on how it's made, might already be dead but still passing a signal through. It would behoove you to brush up on rudimentary subwoofer installations. It's extremely easy to understand and shouldn't take more than an hour of reading . The sooner you understand how that stuff works, the quicker you'll be able to figure out what's wrong. It's very hard for us to trouble shoot for you without being present or fully knowing what your system is.

Also, don't take your car to a big box store again. I can't begin to tell you the horror stories from places like Best Buy and Circuit City did because when thy screwed up, they farmed the job out to guys like me who know what they are doing working in the local car audio shops.

TurboDiesel 07-19-2011 02:51 PM

Re: sub/amp problem
yea well i used to have a buddy that worked at future shop that would do all my installs under the table but then he moved away lol

but today i loaded songs onto my phone and listened to my music that way and it seemed to work great, didnt notice any problems..

so maybe it was my ipod the whole time?? works great with headphones tho lol

TurboDiesel 07-19-2011 07:50 PM

Re: sub/amp problem
okay so turns out using my cell doesnt work all that better lol...
this is the line level converter i have

and i can take pics of the amps/cap wiring if u want?

Diboblo 07-29-2011 08:57 PM

Re: sub/amp problem
If you can, pull your subs... both of them.

They may be wired in parallel:

They may also be wired in series:

Here's the math:

If they are 4 ohm speakers, series wiring will yield approximately 300-400 watts, due to the total 8 ohm load on the amp.

If they are 2 ohm speakers, series wiring will yield approximately 600 watts, due to the total 4 ohm load on the amp.

If they are 4 ohm speakers, parallel wiring will yield approximately 1000 watts, due to the 2 ohm load on the amp.

If they are 2 ohm speakers, parallel wiring will yield GAME OVER, due to a 1 ohm load on the amp. Your amp is NOT rated as 1 ohm stable.

Chances are that the anomalies you are hearing in imaging are due to the protection circuit kicking in as the amp overheats, IF they are 2 ohm speakers wired in parallel.

My money is on this horse...

Snap some pix of the wiring on the subs and the back of the magnet, once you pull them, and post them up for us to look at. The ohm value will be listed on the back of the magnets.

You MAY be able to fix this, if you rewire them (which you can easily do, with some guidance from the peanut gallery), considering you haven't done irreversible damage to the amp.

If you've run the amp too long and done internal damage, it will continue to fail intermittently and will need to be replaced. You will be able to determine this by wiring the speakers to match the amp.

Let us know what you have and we'll be able to point you in the right direction :)


TurboDiesel 07-29-2011 09:06 PM

Re: sub/amp problem
i was talkin to a buddy and he said it could be my amp but i will try and pull the subs and see how they are wired..

i have never done anything like this [as u can tell] so bare with me

so seein as each sub is 500w rms and my amp is 1000w rms i should have gotten 4ohm subs? to match the 1000w?

and if they are 2ohm i need to wire in a series?

now when i wire in a series the diagram looks like the positive and negative are connected, thats bad is it not?
or is it saying that i only need a positive to 1 sub then from that sub the negative goes to the other sub than back out?

LOL sorry if this seems dumb but i fail at electrical but willing to learn

i will go take my subs out now, good thing i got internet on my phone, will update when subs are out

TurboDiesel 07-29-2011 09:19 PM

Re: sub/amp problem
2 Attachment(s)
Ok so I got the subs out, loooks like they are wired parallel? And they are 2ohm... Don't tell me that they ****ed my amp...

Both subs are wired the same as showed

TurboDiesel 07-29-2011 09:51 PM

Re: sub/amp problem
Anyone able to help? See anything wrong?

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