A friend asked me this, I thought I'd ask it here to make sure I'm right.


Let's say he has a headunit with a 5V preout. He also has an amp with the maximum gain at 5V. Now, wouldn't he want to turn the gain all the way up, so that it matches to source voltage and reduces distortion?

 

The exact opposite would be true. He would want to set the gain to its lowest setting, or very close to it. That way the amplifier won't reach its maximum until the amp sees 5v from the source. Mark

 

Yes...gains are "backwards"

Bigger Voltage means less gain. 5V HU + 5V max input on amp = gain all the way down

 

i use the "chain" of level setting to tune
a small powered speaker from DaShack werks wonders
start with headunit RCA's and turn it up until it distorts..back off a few hairs
then follow the signal chain with the same procedure (processors, EQ's, amps, etc..)

the take an hour break (ears need to rest)
then fine tune by ear

voltage is fabulous to know, if you own an oscilliscope......
then you can watch the wave form and when it squares (clips) you have reached distortion

i think i have one at my shop?? might try this later

 

Excellent way to do it by ear.

Yes, an o-scope works great...a nice one that actually refreshes fast though.

I used to have one from my dad(works at a power company) and it worked great. We've got one at our shop that's built into a DMM, not too hot...refreshes to slow to show the wave form accurately.

 

Thanks guys, this is what I thought, but now I can prove it to him.

 

Also, I never thougth about using an O scope to tune, but makes sense, I'll try it out tomorrow and tell you how much it helps.

 

If you have one...infinitely much.

Play lowest tone that will come out of speaker, make the wave as big as possible while not clipping, repeat for each output.

I went overboard on my first set up and had it set so that 0dB tones wouldn't clip at 20Hz...not really necessary

 

I werk for VW and 1 of our mucho expensive diagnostic machines has an oscilliscope built in
i supposed to read CAN-BUS data so i hope it is fast enough
(don't makle me explain CAN-BUS)

i'll try this maybe this weekend

 

OK, I met up with my friend today, and we were talking about this. I told him what you guys said, and he replied "With the gain all the way down, I can't even hear the sub" This is correct is it not? Or is he missing something?

 

Umm...where's his volume set?

Doesn't sound right.

Of course, you can turn the gain up a bit...since it's not going to be at 5V until it's cranked.

 

Lemme call him and ask