The Official Yamaha RX V663 Owners Thread

[Adam.C]

Originally Posted by rwojtalewicz

Yes, I noticed a significant difference. The V663's internal amplifiers are excellent as long as you don't try to push them too hard. If you do, you get loud sound that lacks dynamics which consequently lacks realism. It may sound a bit harsh or unpleasant too, and you'll want to turn the level back down. The harshness drowns out subtle details and so on.

Energy speakers aren't known for their efficiency especially the C-300s and the C-C100. The C-R100s are even less efficient, but for surrounds that's no biggie and the V663 certainly drives them ok in my situation anyway. My HT room is 20 x 15 with vaulted ceilings and that certainly works against the V663's power curve when driving the C-300s and C-C100 to levels that I consider to be enjoyable for movies.

My solution was to either get more efficient speakers or more amplifying power. I love my Energy's despite their inefficiency. Adding three external power amps really did the trick and did it well. It came as a surprise that my Energy speakers sounded even better, especially in the midrange and highs, when I played them a bit little louder than I used to before. I could hear details that weren't audible before. I really like the sound now.

Which external amps would I recommend? Monoblocks! The AudioSource Amp 5.3A did wonders for the center channel and I think part of the big difference that I noticed was there in that center channel. I have no hard evidence to back that up, only subjectiveness. I would buy two more AudioSource Amp 5.3 As for the L and R channels and let the Adcom GFA 545 drive the side surrounds, and the V663 the rear surrounds. The AS Amp 5.3As are heavy and seven of them would weigh about 84 lbs! They have huge toroidal power transformers. They also provide balanced XLR inputs for even better sound. However with the V663, you have no choice but to use the unbalanced inputs. Two more AS Amp 5.3As would run $350 (shipping incl'd) if I can still find them. Unfortunately, Phoenix Gold Electronics which makes AudioSource discontinued the AS Amp 5.3A.

If I were starting from scratch, I would buy an Emotiva XPA-3, three channel power amplifier. It would cost about $150 more than three AS Amp 5.3As. It puts out 200 W /channel into 8 ohms with THD < 0.007% (all 3 driven), that is, if it performs as advertised. The AS Amp 5.3A puts out 250 W into 4 ohms with THD < 0.10%. The Emotiva UPA-7 would reluctantly be my second choice if the XPA-3 wasn't available. The UPA-7 isn't likely to perform as well as the XPA-3. The XPA-3 is much better built, better circuitry, and higher quality components. This is what you want to drive your three front speakers and that's where the difference is going to really be significant.

WOW, thanks for the info. I do kinda notice that when I crank the volume it wont sound quite right. What kinda power can these Energies hold? The Energy website does not give very good info. Just says "up to 125 rms"