Hey everyone I have been researching for sometime to try and clear up my system issues on my 2009 Lexus IS250. I had a flyaudio unit, JLW3, JL 500/1 amp, and a bass **** installed. The problem is the sub sounds terrible. After some research I think I may need a line out converter? Most things on the site talk about tapping into the stock sub. My car didn't come with ML so I'm not sure if I have a subwoofer. Has anyone had experience with this? Any advice on how this is done or what I need and what I need to do would be much appreciated.

 

I installed one for the sub on my wife's SC. I tried using the sub outputs to the new amp but it sounded lousy. Went with line out converters from the L/R front speakers to the amp, bridged to a new sub and viola! super kicker bass.

Cheers,
ZGone

 

I was in a similar situation with my HS250h in 2010 - the model was brand new and any detailed information about audio system was hard to find. I ended up buying a 2-day subscription from Toyota's Technical Information System - it was only $15 but saved me hundreds of dollars in terms of wasted time and parts which wouldn't fit.
The site will give you all the details including full audio system details and diagrams, speaker sizes, connectors - you name it - you can find it.
Once you've full details, you'll know whether your system has subwoofer or not. It's very possible that your car already has a sub (although not too effective though) and when you're tapping into L&R speakers, it's not getting bass anyways so you're technically not feeding any bass to your JL either.
There may be another issue - your factory amp is not handling bass properly and in this case, the amp is the problem. As ZGone said, you'll then need to tap into L&R channels.

BTW : My car doesn't have ML system - it's a so called "Lexus Premium Audio" but it did come with good subwoofer (although crappy door speakers though - I changed all the 4 with JBL components).

 

Thanks for the help fellas! Today I took out the rear sub and ran a line out converter and now I have bass. Thanks for the advice.

Joey