One more unnecessary post, as it brings nothing really new ...
But I feel I must bring my testimony - these Center Stage footers really need burn-in.
I do not keep an exact diary, but about three weeks ago I got another shipment of footers from Steve and inserted them under the ARC 250 amplifiers - previous experiences under the GAT, REF250 have been successful. But this time my faith was beginning to vanish - during some sampling listening I experienced some loss of bass and drive, and after all this time there was no strong evidence of something extraordinary really happening. To be true, as tube hours of REF250 have a significant cost I did not carry the full time burn-in at high levels, as I did with all other equipment - probably something around 40% of time, with power resistors.
However yesterday I hosted a few audiophiles and reconnected the REF250's in the main system. Immediately from start it seemed I had fed the amplifiers with steroids - there was a slam and drive in these amplifiers I never experienced before. The usual suspects - Gershwin by Grofé: Symphonic Jazz, Harmonia Mundi HARMONIA MUNDI HMU 907492 were astonishing - the hands moved on the piano keyboard as if the pianist was sitting there. Someone remarked that soundstage depth was unbelievable in spite of the presence of a few instruments staying more forward - and yes it was. By the time the Rhapsody in Blue was played, there was no doubt - the system was presenting instrument after instrument in a way I never experienced with this recording - rhythm sounded like Bugs Bunny cartoon.
Mercedes Sosa "Missa Criola" allowed me to confirm that bass and focus were also improved - and voice was more tuneful.
My preferred Tchaikovsky symphony is No. 4 - but always played by russian orchestra's, and Mravinsky is my usual choice. Today, when checking a small change in my Roon server I decided to try the DSD Pentatone recording - Russian National Orchestra, Mikhail Pletnev. There is now really something different in these ARC 250 - they have are bringing more of the performance, the extra articulation is showing much more of the orchestra - even at low levels. The sudden changes in this symphony are very well served by the improvements brought by the footers - it is now easier to imagine the hands of the conductor!
The only negative was that the 200 hours will be 10% of the lifetime of a set of KT120 in the REF250's ...