Kinhoang, your room size is large enough for the Tannoys to breathe. If you don't already own the Cary 2A3, you might think about the Wavelength Audio 2A3 monoblocks that are (or recently were) for sale here. I don't know the seller, and I haven't heard the Wavelength 2A3. But my experience with 300B SETs leads to guess that the Wavelength 2A3 sounds less colored than the Cary, i.e., more linear (flat) frequency response.
To repeat: I'm not recommending the seller -- be careful as usual -- but I'm recommending the designer, Gordon Rankin.
To repeat: I'm not recommending the seller -- be careful as usual -- but I'm recommending the designer, Gordon Rankin.