My HU is a deh-3700 made by Pioneer. It is rated to be 4x27 RMS and 4x45W peak.
It currently drives only fronts Infinity ref 6500cs rated to be 90W RMS and 270W peak. So this means that the HU is not powerful enough to run them tehnicaly. I cannot set the HU to go over the 23-24 from the max 30 output on flat( no eq or boosters ). If I do the speakers distorsionate.
I know I cannot bridge the rear and fronts from the HU to get more power for two channels and the speakers would also not work at 2 ohms. The HU has 4 ohms per channel, but that's common sense I guess for low-end HUs.
What I have in the HU is: I can fade the fronts to 100% since there are currently no rears. Also I can set the SLA ( Source Level Adjust ) to have more power for the CD/MP3 source.
I did not try that yet, because my car is currently in the workshop. Do you think that by playing from the fader and SLA could get more clear ( no distorsions ) audible volume?
Please do not post suggestions for an external amp.