I have a pre and power amp setup and I am looking to buy a Dolby Digital Amp. However I would really like to integrate the amp with my current setup and was wondering if this could be done with most DD Amps. I have read that the Yamaha DSP-E492 and it's successor DSP-E800 can connect to an existing setup via the tape loops. Can any other make/model no do the the same thing too. Any help would be greatly appreciated.