I get a more electronic, higher pitched voice for Soundwave (in my head)... probably because he doesn't have a big bulky frame to sound "heavy, booming and deep" - like Dr Claw or unaltered Gen1 Soundwave. He's got too much of a delicate, dainty, spiky frame... it'd be like Mini-Me with that deep booming voice - it'd probably more amusing than intimidating.
Either way, I think the no-talking concept has gone on long enough. I want to see some character development happening with Soundwave. We know a fair bit now about the other Decepticons... just not Soundwave.