well i hooked up the 1500d in place of my sub channel on my belle and i with i had a meter.not much difference in sound. i have it @.7ohm (dual 1.5 ohm) and i just can't hear any difference in the 2 amp's.but as soon as i get my meter I'm going to test the differnce. yes i have 2 battery's to run off of one optima and 1 stinger in the hatch. anyways later

How much power was your Belle the 1100?

yes 1100 @ 1ohm with 14.4 volt's

To quite obviously hear a difference you would need around 2200 watts assuming no power compression. That would gain you 3dB which is twice as loud by pressure -- to your ear 10dB is twice as loud and on bass it's difficult to hear small gains of 1 - 2dB. Since you are using only one speaker we will assume it has a fair amount of power compression... so we'll say more like 2700+ watts to be "obviously" louder.

Check the SPL meter, that is where a smaller power upgrade will show up.

Agreed thats where I was heading.

well i must be deaf these days because the boss say's it's way louder. and the rearveiw is more active now. can't wait for the second one now hope to have it by the 28th

Besides the rear view mirror shaking a few db difference , did u notice any audible improvements by switching amps?

it's little louder but going from 1000 to 1500 there is not that much