i noe how to physicallyn tune it, but realise i have no idea wat it suppose to sound like. can anyone help me with tuning my amp.

when tuning an amp you need to make sure that you can turn your stereo up without hearing the sub distorting or clipping
so in other words volume goes up bass gets louder without distorting

hmmm ok, if anyone is free can i get a hand trying to tune the beast

im bored so gonna give tuning a go, going by mr robertos advice. there are 2 knobs on the amp. SENSITIVITY and X-OVER FREQ. what do these to. there are 2 sets of these. one on chanel 1/2 and 3/4. do these have to be set identical????

your running 2 subs off a 4ch amp correct?
if so then whatever you do to ch 1/2 you have to do the same to ch 3/4

yep 2 subs off a 4 channel

sensitivity depends on your Hu voltage ja?
if its a basic HU then it will be around 2V so set the sensitivity to around 2V
x over freq this is when it cuts out certain freq's or lets mre freq's in, just move the knob till you are happy with the bass