I have seen on several posts here regarding tuning an amp and I have a question.

Why is it that you only turn your HU up 3/4 the way of the volume and turn your amp gain up until you hear distortion and turn it down a bit? Why not turn your HU all the way up and turn you amp gain up until you hear distortion and then turn it down a bit?

Just curious

 

Mainly its because most HU distort at full volume, but not around 3/4 volume. If your HU doesnt distort at full volume then you can go ahead and set the gains at full volume.

Most people just turn the HU volume up till it distorts, then back down a little, then set the amp gains

 

I was a big proponent of using full HU volume (flat EQ) to set the amp sensitivity. I found using an Oscope that t.The Alpine CDA-9815 preouts never clip.

However, I found that I needed to allow some headroom for adding bass or treble emphasis. If I used full HU volume and added 6dB of boost at 50Hz, for instance, I would actually only get a 2dB voltage increase because the HU's preout voltage was already close to maxed.

So what I did is set the HU volume at 29, 6dB down from a max setting of 35. This gave me the head room to add a full 6dB of boost and get the full 6dB increase on the HU preouts. I set the sensitivity with the 6dB of boost.

Hope this helps.