98GS400Lex

So I purchased an aftermarket in-dash Nav for my 98 Lexus GS400. I had the unit professionally installed by a local Boomers audio store. It's a JVC unit and I love it's capabilities however it sounds AWFUL. I noticed that my sub in the back has 0 music/volume coming out of it and therefore I have no bass at all it sounds tinny and terrible. Know from research on this site I know that the factory amp has to be bypassed and the speakers/sub will draw power from the internal amp on the aftermarket unit. I know that the unit has a built in amp and therefore I can't figure out why there is no power going to the SUB?? I read the complete article in the "Aftermarket Radio Installation" section of this forum and I didn't notice anyone mention having to purchase a new aftermarket Amp??? The install people tell me I need a new AMP to have the sub powered independently from that and the other speakers will draw power from the aftermarket unit directly. Is this true?? The problem is I've already spent about $1000 on the unit and install - they say a new AMP with install is going to be another $3-400. Are they feeding me BS or is it true that I need a new AMP to power the sub as the factory amp nor the new unit will be able to do so? Thanks for your help I really appreciate any insight on this.

cjames235

iTrader: (10)

you will NOT want to power the sub with the radio, ALWAYS use an aftermarket amp to power a sub or else it will sound like crap

98GS400Lex

Got it ... thanks cjames235 - much appreciated.

98GS400Lex

any recommendations on a good aftermarket amp?

ThomasGS4

iTrader: (19)

Buddy of mine recently installed a 12" Rockford Fosgate Sub in his BMW and it sounds FANTASTIC! Not too sure which Amp it is, but I will surely ask him for you.

I don't think he payed too much for it either.

o6spdracer

iTrader: (5)

Rockford makes great amps. I've owned at least 10 of them so far. Currently I have the Rockford Power T3002 and T4004. A little older, but great amps. Ebay usually has some great deals on Amps...a lot cheaper than retailers. GL.

Brent77

I'm more of a Kicker man. Another thing is go ahead and disconnect the sub you're running until you get a chance to really power it. The subwoofer will try to pound, but will overheat due to not getting any airflow (excursion), so I'd disconnect it until you actually go all out. And this can actually happen within a week or maybe a year. It took an old sub of mine 1 month to blow from being extremely underpowered (back when I wasn't very smart tried to put a Kicker L5 on an Xplod 300.1 amp).

98GS400Lex

I appreciate the help - love this forum so helpful. Thanks again.