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My MC275 has a clueless sound-change...

I just moved my MC275 from the ground to on top of my rack. Same system and same cables, but the sound changed from musical, well tonal balanced... to thin, noisy, sharp, bottom-less... Anyone of you had such experience and can explain why would this happened? I have the amp sitting close (approx within 2-3 feet from the speakers' mid range section, can the magnetic field affects the operation of the tube amp? or is it that the cables needs to break in again after a few new bends... I am clueless, I switched my interconnect from my Pre to Amp... although it added weight on the bottom end, the mid to the top is still noisy, sharp and forward... please help...
infinity_audio

Showing 2 responses by infinity_audio

infinity_audio OP
186 posts
 
The 12 type tubes were mostly new.
Mine is the V generation. The current production.
V1 I left the original tube, because im using single end.
V2 and V5, i upgraded to a new pair of RCA 5751.
V3 and V6, V4 and V7, I installed a matched quad of RCA black plate 12AT7 which all tested around 75-90.

It is very hard to believe that the tubes are out.

Can it be the power tube?
I am interested in changing the tube to the Gold Lion reissue. How are they compared to the stock tubes?

My connections are as tight as they get...
infinity_audio OP
186 posts
 
oh forgot to mention, I have the current model.
Not the vintage one.

The machine really sounds normal, no pop, no cracking sound, no sparkles in the tube, no abnormal distortion at normal listening level.

*** It will be very difficult for me to get the tubes checked. (If someone in the NYC area is willing to help, I will greatly appreciate it.)
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