Originally Posted by roddis
Will there be any advantages switching from a 3008 to a 5508 processor, if so what is better? I only use my 3008 for the back channels so wondering about changing to a processor and XPA-5..... I don`t use it for stereo music, only surround. Answers will be greatly appreciated
No, not much. The 3008 preamp section is the same as the 5508's. The 5508 will run a little cooler if that concerns you. But sonically, there will be little, if any, difference. Theoretically, separating the big powerful amp signals from the tiny delicate preamp signals could yield an advantage, but on a well-designed and well-made unit like the 3008 it's unlikely to result in an improvement you can hear.
I went from a 5007 to a 5509 (with all-Emotiva amplification) and that was a worthwhile move for me because it let me upgrade from Audyssey XT to XT32 and it gave me a few new features that Onkyo had incorporated since the x07 series (like 4k upscaling for example). I also wanted to use Audyssey Pro at some stage and with Onkyo the only way to do that is to the prepro route, so that was the clincher for me.
The very best value out there right now, IMO is the Denon 4311 which has a special 'preamp mode', plus XT32 plus the ability to run 11.2 with an external amp for the last 2 channels. It's a great unit at a great price and has a great spec.
But long story short, unless you really need a feature that the prepro has that your AVR doesn't, (such as Audyssey Pro ability) then I'd stick with the AVR if it was me.