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Mike3800
10-21-2002, 09:07 AM
OK so I have the courage to admit I bought an Audiovox 8" sub with buillt in 200 Watt amp.

Here's the problem, the volume is good on the sub (very surprised it does well for cheap audio) but now when I crank my sterio to 75% volume, it crackles, not speaker damage type crakle, crakle like it has a short or something, not just the sub, the other 6 speakers as well. Even when I fade the speakers to the front and completley "turns off" the sub, it still does it. It's as if it's amplified my deck. BTW this is not on my Grand Am. I think the problem might be insufficent ground, but I am not sure.

Any ideas appreciated.

oldinstaller
10-21-2002, 09:42 AM
sounds like good ol distortion to me.
you usually dont play any stereo regardless if its factory or not
at that high of a volume level. once you pass about 65%, you start to induce dc into the speakers. this in turn causes distortion which can damage them. (this kind of damage is not
reversable). once they blow, its history.
back down on the volume control or look into adding a additional
amp and changing out the factory speakers.
also......there is a difference between good loud and distorted loud. some people cannot tell the difference thus they end up
damaging their speakers. if it sounds bad at high volume, its bad, period.

good luck:thumbs:

Mike3800
10-21-2002, 11:07 AM
Originally posted by oldinstaller
sounds like good ol distortion to me.
you usually dont play any stereo regardless if its factory or not
at that high of a volume level. once you pass about 65%, you start to induce dc into the speakers. this in turn causes distortion which can damage them. (this kind of damage is not
reversable). once they blow, its history.
back down on the volume control or look into adding a additional
amp and changing out the factory speakers.
also......there is a difference between good loud and distorted loud. some people cannot tell the difference thus they end up
damaging their speakers. if it sounds bad at high volume, its bad, period.

good luck:thumbs:

Thanks for the info... but I don't think that is the problem. Before I installed the sub, I could take the volume to near 100% and it was pretty clean... really... but I installed the sub with built in AMP and it's not as loud as before.


Edit: To clarify the description a little, it' smore of a crackle sound at high volume, it doesn't go with the music like distortion, it is a very high pitch crackle.

oldinstaller
10-21-2002, 03:13 PM
one more bit of information...
check the input wiring to the sub amp. if by any chance you did
happen to hook it up hi-level (speaker level) and you connected
the negatives from both channels (rt- and lt-) that could also
cause problems with the sound quality of your stereo system.
all delco radios from about 82 on up were what they called
floating ground. the negative speaker output was separated
from each other and not common to the chassis of the car.
if by chance you did connect both negative outputs from the factory head unit and/or connected the negatives to the chassis ground of the car, you better disconnect it...like fast if you dont want your stereo outputs to go bad.

use a hi-to-low level adaptor that is floating ground input and
that should prevent the bad things to happen.

good luck:thumbs:

Mike3800
10-21-2002, 05:18 PM
Originally posted by oldinstaller
one more bit of information...
check the input wiring to the sub amp. if by any chance you did
happen to hook it up hi-level (speaker level) and you connected
the negatives from both channels (rt- and lt-) that could also
cause problems with the sound quality of your stereo system.
all delco radios from about 82 on up were what they called
floating ground. the negative speaker output was separated
from each other and not common to the chassis of the car.
if by chance you did connect both negative outputs from the factory head unit and/or connected the negatives to the chassis ground of the car, you better disconnect it...like fast if you dont want your stereo outputs to go bad.

use a hi-to-low level adaptor that is floating ground input and
that should prevent the bad things to happen.

good luck:thumbs:


Thanks again for the info. I bet that's it, I did connect both rr- and lr- from both channels. Factory deck, (pretty nice factory deck really). The car isn't the GA, it's the Hyundai, but I think it probbably uses "floating ground". I'll look for a hi-to-low level adaptor.

So.... couldn't I just (reading from the stickies) wire it in series?

Thanks for answering my questions.

AmIGrand
10-21-2002, 05:42 PM
What year hyundai? Many of them use Alpine decks - virtually identicle to the aftermarket ones. It is worth noting that this is NOT a common ground system!!

Either way, a good line level adaptor is better than the high level inputs on the amp itself. I recomend Peripheral model P-35, should run $15 to $20. Installation is pretty simple, and it comes with good instructions if you are a DIY type person.

Mike3800
10-22-2002, 04:52 PM
Originally posted by AmIGrand
What year hyundai?

It is worth noting that this is NOT a common ground system!!


2002 Elantra

I am not understanding your statment. I don't actually know wether it's common ground or not.

AmIGrand
10-22-2002, 07:10 PM
A 2002 Elantra is most decidedly NOT a common ground setup, if it has the stock system in it now.

A line level converter will change the power outputs from the rear speakers to an RCA level signal to feed your bass amp. It wires in parallel with the rear speakers, so they still work. This is a better way to go about hooking up your bass amp than using the line level inputs built into it - thewy are usually very poor quality. This should eliminate the noise you're experiencing.

Mike3800
10-23-2002, 09:35 AM
Originally posted by AmIGrand
A 2002 Elantra is most decidedly NOT a common ground setup, if it has the stock system in it now.

A line level converter will change the power outputs from the rear speakers to an RCA level signal to feed your bass amp. It wires in parallel with the rear speakers, so they still work. This is a better way to go about hooking up your bass amp than using the line level inputs built into it - thewy are usually very poor quality. This should eliminate the noise you're experiencing.


Thanks.. as of now the subwoffer/amp is disconnected. The car has the stock Hyuuindai electronics sterio. To further elaborate on the problem, when at low volume (20-30%) it didn't make the noise unless I adjusted the balabnce all the way to the right or the left. It made the noise at even very low volume levels.

I'll look for a line level converter and try that. Thanks again.