Y91 Lux Amp Sux,,, A Few Upgrade Questions

[redz71tahoe]

Hello, I have a 2005 envoy Denali with the Y91 lux amp. I'm not very impressed with the sound,,, seems to be a common thing around here.. Now I haven't actually torn into this thing yet and I haven't found or seen the amp I have. I do have a spare amp out of a rolled 04 Yukon Denali, looks like this http://i10.ebayimg.com/05/i/000/ae/6f/e583_1.JPG .

Can any one tell me if the spare amp I have is better than the one I have installed, and if they are pin for pin identical?

 

Also as I'm reading more on here it looks like some models have a sub output adjustment along with bass, treb, fade and balance. I don't have the sub adjustment, guessing because I don't have a sub? Will this adjustment magically show up if I upgrade my amp with one that was made for a sub?

 

Then another question comes to mind, if I install a sub on the sub output of the spare amp (assuming my existing amp does not have a sub out) will the sub do anything at all if the head unit does not give me the option to adjust the sub output?

 

Any input would be great

 

Thanks