under drive pulleys

[hbomb]

I'm getting ready to replace a lot of parts in my 88' gt with some better parts. I'm working on the front engine bay area, which means that I'm removing everything.....the front bumber, radiator, and anything everything else that I'm replacing. I was thinking, while I have off everything should I just go ahead and replace the pulleys with some nice blue anodized underdrive pulleys? Here's the deal, I have a 100 amp alternator that I'm going to install and I'm also putting in a decent sound system....nothing that will break windows tho. Here's my question, if I install the underdrive pulleys, will my sound system be effected much? If so, what can I do to improve apon the power situation with the sound system? Thanks