Vintage Amps for Thiel 1.5


I have a pair of Thiel CS 1.5s that I love for their clarity, imaging, and tonal balance, but sometimes I wish they were a bit more dynamic in the mid bass.

I have been driving them with an old Sony TA-1150 (35w rms, 150w dynamic into 4 ohms), that sounds great but I worry may not have enough power. I usually keep the volume control at around 1/3 - 1/2 and rarely feel the need to go above 1/2, so is my amp powerful enough after all? Is the lack of kick drum punch just the limitation of the Thiels' 6.5" woofer?

Or would I get better punch with a higher watt amp from the '90s? What would you recommend for around $500? 

Bryston 3b? Creek 5350SE? Carver?
aalden
If you can find a working Bryston 3B for $500 - buy it! I have one (and that's what I paid for mine from the original owner).      An excellent choice for ANY Thiels!
Think about adding a sub because that small woofer just can't move enough air!
BAT or Classe.  Match these with some MIT cables and a tube preamp and enjoy.
I have a sub low-passed at 50hz, so they pick up around where the Thiel's leave off. I don't want to mess with their phase with bass management. If I can get more punch with a better amp, I may skip the sub.

Thanks for the recommendations!

I want to stay solid state, so I'll keep a lookout for Pass and Bryston. Would a Bryston 2b be good enough? Those seem to be in my price range.
A Bryston 2B will work well at a bit lower average SPL level. Also depends on your choice of music. Mahler will need a lot more power than, say, Kind Of Blue!