<font color='#000000'>You certainly can get a better sounding amp, but for $600 it would only be a small step up. One amp that I've owned and has received great reviews is the NAD C-320 BEE integrated. NAD has one of the most honest power ratings in the business, and it's 50W per channel is probably an understatement. Don't worry, this amp sounds strong, and unless you have a huge room, it will give you more than enough power. Price? $399. It would leave you with $200 to save towards a better sub. Check out the reviews for this one on the net. I doubt you'll find a comparable review for your current Yamaha. Speaking of Yamaha, they also make a integrated amp, which is supposedly 100W P/C, and is more expensive than the NAD, but I've heard nothing about it. Cambridge Audio also makes a nice integrated from what I heard. It's around the same price as the NAD I think. You may be able to take a big step up if you buy used. Look for used integrateds by Rotel, Arcam, or Creek. You'll notice that most Integrateds nowadays have lower watts. If all you want is 2-channel don't worry, there's nothing more hyped up in audio then wattage. My Arcam that I replaced my NAD with is only 40W, and sounds great in my small room. It's a little better sounding than the NAD, but I would hesitate to recommend it if you have a big room and listen to a lot of hard rock. It's price is $599 but I got a good trade in for it. Do some research, you may get lucky. ...and oh yes, you gotta get a better sub!</font>