Clipping only since I've reinstalled the rear seat. wtf?

[bikinpunk 10+ year member]

I recently re-installed my rear seat in my car. I took it out last week so I can do some rewiring and build a new amp rack in the trunk. For a week or so everything worked fine when the seat was out. However, since I put it back in yesterday, my 4-channel amp clips very badly. My first thought was that it was getting hot, but it's only warm to the touch, nowhere near as hot as I know it's gotten before. I readjusted my gains last night, but all I'm allowed to do is turn it up louder before clipping starts (15/33 on the deck volume). I'm sharing remote turn-on, power through a distro block and the same for ground. My sub amp works fine, without a hitch, and everything is connected on the rack, thus leaving me to believe it's not a short in wires anywhere. The clipping will lessen when I set the hpf to 160hz on the deck, but as soon as I begin lowering it, the clipping gets worse. The music will play for a second, then stop, then come back, then stop, etc etc, until I lower the volume. I've made a seperate post about setting the gain on a brided 4-channel amp. What gets me is that I never had this issue until I simply dropped the rear seat back in. Now one amp clips and the other is fine. Any ideas what to check for? I've had this amp for 2.5 years so I'm not immune to the possibility it's simply a bad amp. Is it possible it's just getting too hot? This amp has only clipped probably 4 times since I've had it, and all those times were in the summer.

One other thing, is that now my mids aren't playing at all, but my tweeters are. I've only allowed clipping to happen a few times, so surely I haven't damaged the speakers already (rainbow slc 265's).

Click to read more...

 

[saywhat? 5,000+ posts]

what does clipping sound like exactly....

 

[BassAddictJ 5,000+ posts]

sounds like you may have a shitty power/ground connection. if there's a bad connection somewhere there, that can send an amp into maasive heat makeing. may not actually be clipping. if the gains and everythign else in the system is still constant, it shouldnt be clipping. check those wire connections one the power supply side. hell check all ur connections. MAYBE its something with those preouts on the deck, maybe try putting a differant deck in there and readjust ur gain with a dmm and see if it still wigs out. check those connections first though the ground especially

 

[SQBubble 10+ year member]

my vote is ur having a sort somewhere, check ur speaker wires of ur components, maybe while putting ur rear seats, some wires got damage ...

 

[bikinpunk 10+ year member]

what does clipping sound like exactly....

I'm not sure what you're asking. If you're addressing my wording, then I believe you know what I mean by clipping. If you're half serious, then when I say 'clipping' I'm referring to a lack of sound, as opposed to an instance of sound.

If a tree falls in a forest, and noone is around to hear it, does it make a sound?...//content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

 

[bikinpunk 10+ year member]

my vote is ur having a sort somewhere, check ur speaker wires of ur components, maybe while putting ur rear seats, some wires got damage ...

Would the crushing of one set of speaker wire (could very well be my passenger side is crushed) cause the amp to go into protection like that?

I actually reinstalled my ground, remote, and power all last night just to make sure, but still had the clipping problem this morning on the way to class. It really concerns me that something has fried. The amp is set up on a fused distro block and I haven't blown any fuses. I'll check the speaker wires tonight though. In the meantime, any other ideas? Is there a good way to evaluate the amplifier itself without benching it? I've had it for 2.5 years, and it's a fairly cheap alpine amp. My gut is telling me that it's finally just bit the dust. Hopefully not, though.

 

[thch 10+ year member]

I'm not sure what you're asking. If you're addressing my wording, then I believe you know what I mean by clipping. If you're half serious, then when I say 'clipping' I'm referring to a lack of sound, as opposed to an instance of sound.
If a tree falls in a forest, and noone is around to hear it, does it make a sound?...//content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

clipping is a specific form of distortion caused basically by the amp wanting to put out more then it can, and hitting a limit. and since audio is rapidly changing, it hits the limit several times per second, changing the sound. but the sound continues, albeit in a distorted manner.

the "clipping" you refer to is more aptly called "intermittent output" or something like that.

and probable causes for it are:

* Protection circuits

* poor/intermittent connection to amplifier, speaker, or HU, or inside any of these parts/connections.

* skipping of CD.

 

[bikinpunk 10+ year member]

Okay, now I get the difference. I've always thought clipping was when you have intermittent signal. My bad.

Still, can the crushing of one set of speaker wires cause both sets of components to not play? It's possible that one set is grounding since reinstalling the seat?

Are we fairly sure it's a wiring issue, and not an overheating issue? Like I said before, when my mids try to reproduce bass below 160hz the playback cuts out much more frequently. I even notice now that my mids won't even play.

 

[blackonblacksls 10+ year member]

ground the shit out of the four channel. run a ground from the bat to somewhere close to the grounds of your amps. i dont know what kind of amp you have but i have had that problem with a few pioneer amps. they cut in and out and for some reason just seem to get better after some rediculous grounding.

 

[BassAddictJ 5,000+ posts]

if you damage the speaker wire and they cross and arch, that can cause the amp to go into protect in order to not fry itself...check ur speaker wire connections...itd make more sense if the amp goes completly into protect and not just cetain speakers not working...if alllllllllllllll the wires everywhere are fine......and you try with another deck and problem still persist....then that amps toast (about to be)

 

[bikinpunk 10+ year member]

itd make more sense if the amp goes completly into protect and not just cetain speakers not working...

I meant that my mids don't work at all, for some reason. When the amp does go into protect for whatever reason, the tweeters go out. It would be the component SET, but my mids are already not playing.

Like I was asking tough, I'm quite sure that BOTH sets of wires to the x-overs aren't crushed, but it's likely that ONE set is. Why would one set cause the amp to shut down like that, only when I turn it up at higher volumes? It just seems more logical that if there is a short somewhere, they wouldn't play at all, instead of playing up to 13/33 on the volume before shutting off. Someone care to explain? Is it just because there's an increase in voltage when turning it up and it gets to a point the amp simply can't handle?

 

[bikinpunk 10+ year member]

Got it. My wires at the driver's side crossover were frayed and not making a solid connection. I'm willing to bet the power was grounding somewhere on the crossover's ground and causing a short. Either way, thanks for the help. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif