I'm gonna stick my neck out in another direction. This is such an inexpensive, safe approach it's almost risk-free.
How about an Onkyo A-9555 class D integrated amp? At its suggested list price ($799) it would be competitive, but you can get it at $500 and below almost anywhere (e.g., J&R, B&H, and Amazon, which has free shipping and a 30-day trial period). And you'll need that 30 days because it takes a good 75-100 hours to break in. I hooked up an iPod and FM tuner to break mine in 24 hrs/day. By the third day it began to astound me. It has extraordinary speed, clarity, and transparency combined with a particularly articulate and extended bass, and an overall natural sense of ease that's usually missing from inexpensive fast, detailed amps.
Can't say how it sounds against a Naim, but I like it better than what I've heard from Creek, Rega, and Cambridge, including specifically the 640A. It sounds more like a 150-200 wpc Musical Fidelity, and even there, I think its midrange is a little smoother and more natural than the MF's.
It should be an excellent match with your Totems as well. Its 85/170 wpc into 8/4 ohms fits your STtaffs' recommended power of 20-100w at 8 ohms. The Onkyo's ability to deliver current should help your STtaffs perform at their potential in bass extension and clarity, and will also bring out the best in Totem's strengths in speed and clarity.
How about an Onkyo A-9555 class D integrated amp? At its suggested list price ($799) it would be competitive, but you can get it at $500 and below almost anywhere (e.g., J&R, B&H, and Amazon, which has free shipping and a 30-day trial period). And you'll need that 30 days because it takes a good 75-100 hours to break in. I hooked up an iPod and FM tuner to break mine in 24 hrs/day. By the third day it began to astound me. It has extraordinary speed, clarity, and transparency combined with a particularly articulate and extended bass, and an overall natural sense of ease that's usually missing from inexpensive fast, detailed amps.
Can't say how it sounds against a Naim, but I like it better than what I've heard from Creek, Rega, and Cambridge, including specifically the 640A. It sounds more like a 150-200 wpc Musical Fidelity, and even there, I think its midrange is a little smoother and more natural than the MF's.
It should be an excellent match with your Totems as well. Its 85/170 wpc into 8/4 ohms fits your STtaffs' recommended power of 20-100w at 8 ohms. The Onkyo's ability to deliver current should help your STtaffs perform at their potential in bass extension and clarity, and will also bring out the best in Totem's strengths in speed and clarity.