As I said in my other threads these valves are very, very special in terms of sound quality.
Remember they arrived on Thursday last and were fine to Saturday. A friend visited and during that visit we compared my curfent interconnect fave with another. When I switched the amp back on within a few minutes one of theKT88's shone very bright orange/red. I switched off and waited -thinking that maybe I didn't wait long enough for 'cool down'. When I switched on again all was well.
I switched the position of the valve to eradicate a possible amplifier problem. All went well on Sunday and Monday.
This morning I switched on and and left the room for the system to warm up for 10 minutes. WhenI entered the room the same valve (in the new position) was aglow. Switched off and waited. Switched back on and all seemed well. Within half an hour another two valves did the same thing. Frightening!! Can't possibly leave the room with the system playing. Lorenz has agreed with my opinion that the valves haven't been tested long or thoroughly enough and has agreedto give me a full refund.
The Gold Lions are behaving impeccably so it isn't an amplifier problem.
Aaah but I do miss that fantastic sound.
Here is what the glow looks like.Scary??
Note: The12AX and AU7's are fine and sound great.