Re: Installed components - need gain help
Setting gains by hear is a bad idea. A worse idea would be setting gains by ear with a test tone. A test tone is only really useful for setting the gains with a DMM. If you're going to set it by ear, I would use a song that gets pretty loud (not acoustic only etc, try some rock something) and then keep turning it up until you think it's loud enough or you hear distortion.
EDIT: As for your tweeter problem, I'm not sure why that would be happening. Also, when you set your gains, you should have your head unit volume number around 37 or 38. Above 75% volume, many head units begin to clip the signal they send out, so you should set your gain with your head unit around that volume, then only ever turn it up to that volume (unless it's a song that was recorded at a lower volume, which in that case you can turn it up more because you have the extra head room). Sorry, I had forgotten to mention that very important step.
2000 Volvo v70
HU: Pioneer MVH-8200bt
Front Stage: Focal IS-165
Sub: Alpine Type-R 12"
Speaker Amp: Polk PA660 bridged to 150x2wrms
Sub Amp: Alpine MRX-M50
Sub Box: Custom, tuned to 33Hz