Originally Posted by mistryn
How much should I set gain for the speaker and the subs? less than 1/4?
As I have idrive I cannot tell what volume I am on at the HU as it does not show a numerical value
Your cousin should be able to do it with multi-meter.
Or if you are good enough to identify soft / hard clipping, then you can do it without multi-meter.
You have rear speakers though to start and identify the max volume of HU.
Turn down the gains to minimum.
Turn the amp to 4 channel mode.
RCA to Ch 1&2.
Turn on the HU and volume to max (use rear speakers to hear when sound is not increading any further.)
Set your gains for mids.
Once you are done with above, turn off the HU / car and swith RCA cables to Ch3&4.
Repeat the same procedure as above to set gains for your sub.
Once you are finished with all put the cables to Ch1&2 and switch the input mode to Ch1&2 so that all can take the input from it.