Haven’t seen this specifically addressed in my time browsing. I see some of you are using a DSP in your aftermarket audio systems. Does the stock head unit do any kind of weird equalization or bass roll off with volume, to make a factory integration DSP pretty much a necessity? Or is it a relatively clean unmolested signal from the speaker outputs?

I'm almost certain the stock head unit A) has a lowered bass response, and B) progressively rolls off bass as volume is increased to keep from clipping.

I think in one of the Taco Tunes install videos, they show the general pink noise output curve on an oscilloscope, and you can see the bass curve is definitely rolled off.

You can mostly bypass the internal DAC by using the AUX input. I have a Dragonfly Red DAC plugged into the Aux port, and play FLAC or AAC (even pandora streaming) that makes a world of difference in the quality through stock system.

After installing the two Kicker Key 180.4 amps, and better speakers, the DSP does a lot to restore the bass curve. It is nice to have the adjustment knob for the sub, as certain songs, when played at lower volume produce overbearing bass, and then when you crank up the volume, the sound balances out. I assume this has to do with the fact that these amps are auto-tuned at slightly loud volume, so the head unit has rolled back bass response a bit. When you lower the volume, bass is cranked back up.

I'm not familiar with manually tuned DSP, but I imagine you could tailor it closer to the desired response. Either way, DSP has greatly increased my enjoyment of the stereo.

Narat

Well one day i was driving and the stock head unit broke in to this old George Carlin routine... Actually, I have a 5 channel pioneer amp using the speaker level inputs, and i found that by turning off the auto speed / volume it fixed most all of the issues. i use Bass -1 or 0, Mid -1 or -2, Treble +1 or +2. Set the crossovers on the amp and usually leave the bass knob at 1 or 2 o'clock. (depending on what i am listening to).... All my music is played off USB.

Thanks. Just got done installing my audio system and can definitely confirm bass roll-off with increasing volume. I actually have a couple-year-old Kenwood head unit and the Crutchfield-bought install kit sitting on a shelf. I might go ahead and stick that in.