Tube change.

@sidog1460 

You don’t have your amps plugged into your Rhea PC, do you?

Wow! What beautiful amplifiers! Sorry that I thought that they might be VTL's as your's seem to be in another league altogether, at least compared to lower-end VTL's. So all I can say is keep playing with input tubes. Apologies for rambling on about the wrong amps.

Agreed. Nice looking amps... that's a lot of tubes. 

I have used a number of different Sophia tubes and they have sounded superb, warm natural and detailed. While they are not Takatsuki... they are upper tier. 

@curiousjim When the TA Rhea and filter came out Tom Vu the designer allowed me to audition it at home and recommended listening to my music w amps plugged into the Rhea not into the wall. The Rhea was made to handle high voltage components and the noise floor dropped significantly(among other benefits) with the amps plugged in. Couldn’t imagine going back to plugging them into the wall.

@sidog1460 What KT-88’s are you running now? I have a little Dennis Had Inspire KT-88 that is a clean, simple design with only one 6SN7 or SL7 signal/driver tube.  The Inspire can run 6550, EL34, KT-66, -77, -88 and is very sensitive to tube rolling, I can distinguish subtle and not so subtle differences between tube models and brands.

It came with New Sensor Gold Lion KT-88’s, a clean, transparent, well balanced tube.  I purchased a set of Shuguang Nature KT-88-T and found them “darker” with more bass response, a bit more bite in the midrange and good extended treble.  They were only $65 ea. You may want to take a look at the Shuguang if you want to experiment a little without the investment SE’s would require for eight tubes.