Sub cutting out - not really high vol

[amedeuce 10+ year member]

Ok I also have post about wiring the dual 4 into 2 channel amp - it's a few down

Anyway took back the POS absolute amp and got him a memphis mc250d to match the memphis 10 dual 4.

I did the entire install, good ground, wires tight everything good. Sub wired like this (see attachment)

The h/u is a kenwood. max vol is 35 set gains with 50 hz. h/u at 25, bass at 8 (all the way up).

Set gains, turned bass on 0 *note* at this point with 50 hz sub did not cut out.

Play CD, cannot turn vol past 22 with out bass cutting off, granted it is loud but.

It's the Sub only, amp is NOT in protect.

The h/u has 2 preouts, but not specifically for sub.

There is not an amp for his door/dash speakers. Everything is controled by h/u.

I guess the only way to control mids and sub seperatly is to have a seperate amp for sub and speakers.

Click to read more...

 

[johnecon2001 5,000+ posts]

voltage drop maybe, your starving the amp. try reving the engine while playing a song and see if it does the same thing. if it doesnt... you know you need more power.

 

[amedeuce 10+ year member]

voltage drop maybe, your starving the amp. try reving the engine while playing a song and see if it does the same thing. if it doesnt... you know you need more power.

I'll ask my friend how it was when he drove home. What can he do to fix it? alt? I was thinking maybe a larger inline fuse. The amp kit he bought came with a 60 amp fuse.

 

[JoseMCeee 10+ year member]

i believe if it had something to do with the fuse, the fuse would have fried. Im sure its a voltage drop problem. Which means that the amp, usually the sub amp, will just turn off when the volume is loud because it recieves a voltage lower than 12vs or so. The way to get rid of this is getting a bigger size wire for the amps and the wire from the batt, try doing the big 3, a better batt, or a new alt.

 

[amedeuce 10+ year member]

i believe if it had something to do with the fuse, the fuse would have fried. Im sure its a voltage drop problem. Which means that the amp, usually the sub amp, will just turn off when the volume is loud because it recieves a voltage lower than 12vs or so. The way to get rid of this is getting a bigger size wire for the amps and the wire from the batt, try doing the big 3, a better batt, or a new alt.

It's my friends jeep, I'm gonna check the big three out, the amp kit he bought is a 4 gauge.

I'm sure the big three would help out a lot.

This is exactly what needed to happen to prove to him it needs to be done. But he probably won't want to have it done.

I did it to my Truck, it cost me around 20 buck and about an hour and a half to do it.

 

[Termlab 10+ year member]

if its a memphis 250 watt amplifier i doubt its causing all that much strain on a jeeps electrical system //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

it sounds to me like maybe (just maybe) you thought you wired the sub like it is in your diagram... maybe its wired outta phase. but then it would probably kick into protect mode. sounds odd.... maybe somethings wrong with the amplifier?? i had a JL 500/1 and it wouldnt kick into protect, but after about 30 seconds of play time it wouldnt put out any sound.

 

[amedeuce 10+ year member]

if its a memphis 250 watt amplifier i doubt its causing all that much strain on a jeeps electrical system //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

it sounds to me like maybe (just maybe) you thought you wired the sub like it is in your diagram... maybe its wired outta phase. but then it would probably kick into protect mode. sounds odd.... maybe somethings wrong with the amplifier?? i had a JL 500/1 and it wouldnt kick into protect, but after about 30 seconds of play time it wouldnt put out any sound.

I was thinking the same thing, it's only a 250. But, Im sure it's wired correctly I'll triple check. Yea the amp does not go into protect mode. I turned it up to were the sub would stop playing and looked at the amp - not in protect, wiggled everything, no change, Go back to h/u turn it down 1 number and sub comes back on. Now granted like I said it sounds great, it just shouldn't be cutting out. Let's say it cuts out at 24 on the volume, at 23 it will play fine and not cut out

 

[johnecon2001 5,000+ posts]

can that amp not handle the volts coming from the HU maybe? What unit is it? I doubt thats the case, but maybe the amp is faulty.. is there another amp you could test with?

 

[amedeuce 10+ year member]

it's a kenwood, Im not sure the model. I'll have to find out, He's coming back over tomarrow so I can carpet the box and amp board.

 

[Termlab 10+ year member]

another thing it could be shorted coils on the subwoofer //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif but that would put it into protect mode also...

sounds like a faulty amp to me. but i couldnt be sure without actually looking over the vehicle myself.

like mentioned above, try swapping his amp, with somebody elses.... i'm sure you know somebody that would let you borrow their amp for a few minutes to help out //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[amedeuce 10+ year member]

sounds like a faulty amp to me. but i couldnt be sure without actually looking over the vehicle myself.

Well when was the last time you were in california. Well that's too long, come on down and look //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[whiplash 10+ year member]

I'm having this same problem with my friends amp so I was looking around these forums for others. So far I've found this thread and another thread with this same exact problem, and both of you have Memphis amps. My friend's amp? Memphis 500d. I've got a 2 or 3 year old 1000D that I've never had a problem with, but maybe Memphis is having problems with their newer amps?