Amplifier for Avantgarde Duos


I'm looking for an amplifier for my Avantgarde Duos. I'm currently using an Art Audio Carissa with an ASL Flora for the pre. With this combination I still get a shrill presentation on some recordings. My pre has a nice rounded top end so I feel comfortable with it. Does anyone have any suggestions for the amp. Again I prefer something that softens the shrillness. Some amps have a lean top end. The Carissa is almost there.
frontier1
Hi Chris- Since I know you are at least contemplating a switch to a 300B based amp- Here is a link to a review of 11 different iterations/brands. You may find the observations/info helpful: (http://www.stereophile.com/features/229/index.html)
I have a pair of Unos which sound excellent with a Art Audio Diavolo.The amp is also dead silent.
Mike
What cables do you have? It's possible a change in cabling may be a cheaper alternative. A warmer cable such as Cardas,Purist,Audience,Transparent,MIT would do the trick.
I owned the Duos for about 3 years and I thought they far and away sounded best with the Audiopax 88 mono amps. I owned the BAT VK150SEs and used them on the Duos which to my ear was not a great combo, but I guess others disagree since they did show with them on the Trios a few years back, but then I didn't like the sound of that system either. One nice thing about the Audiopax amps is that the tubes are cheap and the sound warms up really quick.
Thank you for these excellent suggestions. I now have the Avantgarde integrated model 3 amplifier which sound fantastic for these speakers. The shrillness has disappeared and now I have music. I'm still looking for the equivalent in an amp pre combo which more readily suits my setup configuration. Are there any thoughts on Pass amps? The other consideration is amp/pre impedence matching. How much does this affect the sonic outcome?