Question about Alpine amps and other digital controlled amps (GAINS)

[RoudyruffKK 10+ year member]

i have an alpine mrv-f345 and all settings on the amp are digital. it's a 4channel amp and i'm using it to power my front mids and front tweets. now the problem is i don't understand how the gains work it goes from 0.3-4 or something like that. i'm assuming 4 means gains are all the way down and 2 would be somewhere around half way. i hate this method as i can't get it any more precise than what the display reads. although i know it'll be close enough it's still a pain in the *** to read. so why are these amps, i'm not sure if it's just alpine, using these stupid digital display things and why is 4 max instead of say 5 or 10?

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[Slaugh 10+ year member]

the gain is used to match the amplifier input voltage to the max voltage your hu will put out on the pre-outs... so the lower is the voltage you adjust on the amplifier, the louder it will sound, but you must adjust it correctly otherwise you risk clipping out the signal to your speakers and damaging them... also note that too high (low voltage) gain will induce distortion and hiss to your speakers... so the thing is, you got set it to the maximum your hu will put out on normal listening so you enjoy the best your sound without distortion or risking bottoming them out and damaging them...

you would be doing good setting it at the hu at 75% of it's maximum volume and using a DMM will be the best choice (there are tutorials on how to do this everywhere, so search)... hus usually increase significantly the THD above 75% of it's maximum volume

i believe you will need to connect your hu to the amplifier using the AI-Net cable... i think that way you will be able to do the amp adjustments directly on the Head-unit... i dont think my 9815 does it thou, i think only 9835 and newer will do so... i could be wrong thou

but well good luck... i have an alpine hu and other 2 alpine amps and i can't get them to **** work good even with DMM or not... i just assume now my hu has faulty pre-outs...

 

[RoudyruffKK 10+ year member]

well at the moment i'm not sure what my gain settings are i know for my tweets i have it pretty high like around 3.4 and my mids i have them around 0.8 or so (this is just me estimating) but they are in that range. i have no problem with the amp + hu, i'm going to drop off my car in a sec to get the fiberglass work done for the sub box and i get my sub amp (arc audio kar900.1d) early next week so i won't know til then how the sub will react.