If you still have the Onkyo, for sh!ts and giggles, you can use the LCR amp in, being driven from the Anthem pre-outs. See if your sound quality is restored.
Remove the three jumpers at top left and run cables to "Amp In".
Thanks for the idea.... I still have the 989 (doubt I'll be able to sell it here as it's a 240v model that I run off a transformer!!).... but I didn't have the 300 by the time I read your post....
The OP liked the sound of an Anthem MRX700 in a different room with different speakers. I suspect that much of the sound that they liked was due to the speakers. However, ARC may have been used, and if so it may have contributed to what they liked with the sound. We just haven't been given many details.
If they haven't done so it can't hurt to try the ARC and see if it improves the sound. I think room correction can have a significant impact on a system's sound (either good or bad.) I think far more impact than d/a converters, amplifiers, interconnects, etc.
Thinking back, I'm not sure it was just the speakers making such a big difference (although I'm sure they can!). The demo and what I heard at home were a long way apart.
If his Anthem still sounds that bad to him after a processor reset, then there is probably something wrong, or defective.
That might have been the case....
To the OP another thing to check, if you haven't already, is the speaker connections to make sure you didn't switch the polarity when hooking up the new avr.
Thanks, all wiring was checked, double checked and found fine.
Thank you all for your helpful input, it's appreciated. To cut a long story short, I wasn't going to get to do ARC for at least a week, and wasn't convinced it would make that much of a difference.
After further testing, it would be unfair to say it sounded "bad", but it certainly lacked the "drive" of the 989. Also, on further checking, I realised that the picture produced on the TV was noticeably "washed out". That was enough for me. I took it back, paid the extra wonga (which I could really have done without at this time of the year!) and took home an Integra 50.4.
Am still sorting out the Integra.... not hooked up yet.
Perhaps I should have given the 300 more of a chance. It certainly has a lot of fans, and is meant to be a great choice for those who value sound quality over convenience and gadgets. Mine might have been defective.... what I did notice when going through the manual was that one page had a faint cup ring on it.... this may well have been a returned item re-sold?
Whatever, it's done now. I'll plug the 50.4 in later, and hope I made the right choice! Thanks all again, and Happy New Year to you all.