New here and have a couple questions......

[G-Coupe]

Ive been in to car audio for probably 13 years or so, but some thing still confuse me which may be simple things to understand.

first question: Is it bad to run two separately fused 8ga wires from the battery to two different amps? I originally only had a sub amp(400w) and added a 4 channel amp just recently running 300w and didnt want to run 4ga to a dist. block since the new amp came with a 8ga wiring kit so i just added another run of 8ga.

Second question: My 4 channel amp is going in to protect mode when i turn the volume about midway for some reason. I am thinking it is a bad ground because when i use a DMM using the continuity setting across my amp ground terminal and the grounding i get a constant beep out of the meter like the ground is fine but when i turn the stereo up to the point that it starts going in to protect, the beep on the meter cuts in and out sometimes for a few seconds. Is this a sure sign of a bad ground?

Hope all that made sense.

[meridianofinsanity]

It's not bad to run the two different runs just make sure you are not consuming to many watts because amplifiers draw in more power than they put out so if an 200 watt amp had a 90% efficiency rating than its using 220 watts

The ground might be the problem for the four channel but make sure all of your speaker wiring is good and you aren't shorting out but to improve that ground make sure the paint is scraped away from it and tighten it if it shakes loose use a lock washer

[JasonJones]

You don't want to measure for continuity for a ground. Measure voltage with your probes in series between the negative of your amp and the grounding point. Closer to 0.00 you get the better.

Also, is the amp actually going into protect or does the audio output just discontinue, or does the amp shut off? And does audio come back automatically or do you have to power cycle the amp?

In regards to the wiring, no, it is not bad to run two 8 gauge wires. You should probably get one larger gauge then run to a distro and go 8 gauge off of that. Major thing is to ground both of those amps to the same point though.