What is a ac heap line driver and what does that do?

 

I think he meant - " a cheap line driver".

 

a line driver takes the low level signal, at the rca level, and boosts it...say you have a headunit with only a 2volt or less output, this means you will have a lower signal to noise ration and more chances of noise getting into the system, but...if oyu use a line driver, you can boost this signal up to 5, 8, 10 or even higher voltage.

a lot of processors today come with built in line drivers now...such as most of the audiocontrol stuff... i have a DQT boosting the signal coming out of my Z1

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