Thread: Hardware Review: JL Audio CL-RLC volume controlled preamp

If the sound output is weak and you need volume control after the HU, then it seems to me that you would need TWO CL-RLCs. One as a pre amp after the soundcard, and another before the amp. The pre-amp part is a set and forget thing, AFAIK pre amp levels are to remain 50% and up, set once, unless you switch sources.

So if you can't use the HU and need a volume control, then yes, use another CL-RLC. I can't see why diff. balanced control in the cl-rlc could cause any problems. I use it as a pre-amp, never touched again; volume control is done by the HU - > amp.

i have a odd issue similar to this-- i cannot use my aux input while the carpc is running(both tie into the input of the rlc's). i believe it has something to do with grabbing power/ground from different locations for the carpc, and my external crossover module that the aux input uses..

but i really don't use either at the same time, so it's not worth trouble shooting for me..

you might need to try getting power from the exact same location for both the carpc, radio, and rlc..

Why would sound output be weaker (almost non-existent) by inserting the cl-rlc in between the sound card output and the HU pre-amp input? I have tried 2 different cl-rlc units. I have a ground block and everything shares the same ground so that's not it (even have a 6 gauge ground wire going to battery neg from the block, which is chassis grounded in the trunk).

The sound is actually louder without the cl-rlc in place (but still too weak). I can turn the HU up to max (it has 5V output) but it sounds crappy.

I also tried using the headphone output of my phone to the cl-rlc to the HU and that does NOT work. Phone directly to HU works fine, plenty loud. Much better than carPC but that doesn't help me! Consistent behavior though. I suspect that the CL-RLC is not accepting the unbalanced input I am feeding OR the HU is not accepting the output of the CL-RLC (too high voltage and clipping it?). I should try going from the carPC to the cl-rlc direct to the amp. Perhaps it is the output stage overdriving the HU line level input.

Originally Posted by rcdash

Perhaps it is the output stage overdriving the HU line level input.

i think that is the problem

^ that WAS the problem. The HU input expects 1V max line level signal. Output directly to the AMP works just fine. So this isn't really a good solution as a pre-HU volume control.

thanks for the update. good to know.