Integrated amp upgrade


I'm using a Classé Audio CAP-151 to drive my Thiel CS 3.7s at the moment.
I'm not sure if i should upgrade, anyway if i do so i'm looking for a used integrated amp in the $2K to $3K price range with balanced inputs.
I've seen a Sugden IA4 for $3K and a Musical Fidelity KW 550 for $2,4K but it's not balanced.
If i upgrade it would have to be really worth it otherwise i'd rather keep my CAP-151.
I have someone who would like to buy my CAP-151 for $1,6K.

128x128thieliste
If you’re thinking of a pair of 7.2s, you can’t fiddle around with little amps. You need big power, so look to Threshold or Pass or Krell, etc. If you like the sound of the Classe, look to one of their bigger amps. With a volume control on the Hegel you might not need a separate preamp so more of your resources can go into the amp. Couple of possibilities:
https://www.audiogon.com/listings/solid-state-threshold-stasis-7-0-2017-01-20-amplifiers-75243-dalla...
https://www.audiogon.com/listings/solid-state-pass-labs-x250-solid-state-amplifier-2017-01-21-amplif...
https://www.audiogon.com/listings/solid-state-classe-ct-2300-balanced-stereo-amplifier-2017-01-21-am...
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As a prior Thiel owner, I recommend a large ss amp with a tube preamp.  I don't think you'll be content in the long run with an integrated, especially with cs3.7.

As mentioned by mani-2, Pass, Krell, Threshold...also CJ, Belles.  Good luck!