this is probably a dumb question...but can i pull power for my line driver from the factory amp power wire? is that a constant power wire? i'm going to install a rockford rf-bld since my pre-amp signal is too weak for my JL amp and i have to raise the gain to the max which brings in lots of noise (hiss/static).

i was going to use the factory amp remote wire to get the remote signal for the line driver and ground to one of the bolts holding the factory amp in place (after sanding). i've read a bunch of reviews of people using the rockford bld and some said they use those bolts to ground the line driver. i'm going with this driver because there is lots of good feedback on them for the TL...i haven't had luck with cheaper drivers or ground loop isolators (still lots of noise).

i think the amp power wire is constant since there is a remote wire to turn it on but i wanted to make sure.

 

Not sure... I would try and see. In theory it should work I guess.

 

tried two different line drivers and they both worked grabbing power from the amp power and the amp remote on wire. i grounded to the bolt holding the stock amp.

weird thing is that the rockford bld line driver gave me about 1V output while the JL line driver only gave me 0.1V.

i was getting about .060 V from my head unit pre-stock amp so why is there such a big difference with the line drivers? it just relates to how much gain i need to use on my amp (JL xd500/3 amp).

 

What kind of signal are you passing through when measurements are taken and what is the volume level at?

 

1000 hz sine wave uncompressed file from JL website with stock head unit at volume 30 out of 40

 

Something is not right there.... Should have a stronger signal than that. How was the sound on the factory amp?

 

OEM sound was fine. During this install I tried two OEM head units and two OEM amps and they have consistent results.

I'll do some more measurements with a DMM tonight to make sure I was reading them right.

 

How is the sound on the aftermarket amp?

 

Also, if your using a jl amp you shouldnt need a line driver.... What amp?

 

JL xd500/3. i originally didn't use a line driver but i couldn't get my gains past 6V on the JL amp output since our head unit output is so low. so i used a line driver to get me there and the sound is definitely cleaner and stronger...but a hiss limits how much gain i can add (my amp is spec'd to give out 75w...17.3 V...to 4 ohm speakers but i can only give them about 6 V since i have a hiss i've been trying to get rid of for months).

the hiss is a whole other issue and i've had many people try to help me with advice but no luck (LOCs, drivers, new ground spot, new amp, new speaker wires, new head unit, new rca cables, everything soldered, etc).

i'm ok living with the hiss right now i was just curious about the line driver difference. tonight i'll check the stock output without a line driver and with the JL line driver just to make sure i didn't read them wrong. i tried a line driver to keep my amp gain down to get rid of the hiss...but it's there no matter what so maybe i'll see how it all works without the line driver now and save some money

 

Yeah the low voltage definitely seems off. Perhaps the hiss is produced by the amp. Is there another amp you could try to see if that fixes the hiss?

 

I bought my amp used so I bought another brand new one in the same model but hiss was still there so I returned it

 

Boy... so you tried two head units... must be something to do with the power connections...

 

everything is soldered haha. i've tried so many things to troubleshoot this over 6 months but no one has been able to pin point it. i knew the TL audio was going to be troublesome but this will make me never want to do an audio system upgrade again haha

 

I have no line driver straight to a JL 700/5 and there is very little noise and my gains are not set high. something wrong with your HU signal is seems to me.

 

Do you know where you grounded to under drivers seat?

Any way you could check the voltage going into your amp?