mr12volts

And to add to the other guys question....ask you installer about adding a signal line driver it is a simple install and adds 1/3 to 2/3 more signal power to any audio sys with an amp....they start around $30.00 for a *(PAC) line driver and PAC is a great mobile audio accessorie...you can get others like audio bahn,kicker,audio controll,.,,but then ur gona spend a lil more then $30.00 in parts :D ...

well, what are you looking for in your audio sys?lots of bass,rear fill?if you want rear fill just add a sub to the factory location...you will need to replace the factory amp for best sound but it will still sound like hammered !Removed!....the best sound we have achieved from your style lexus is removing the factory sub and building a custom box or in most cases just a prefabricated box and a new amp,and if you plan to keep the factory radio you will need a line out convertor or an amp with high level-in put...but for the best sound you need to replace the oem radio .......u will need to by-pass the factory amps if you go that rout....a company named american international makes dash kits for most lexus cars....u got a high dollar car so it will cost some$$$ to get work done to it,any work....

your speaker is not grounded!!!if that was the case it would shut down the whole sys....the problem is in the factory amp...and if it"s not to late do not go to lexus for an audio related problem unless you under warr....go to your local audio shop and save some$$$$$$$4