Rerurn to Romy the Cat's Site
In the Forum: Audio Discussions
In the Thread: Initial thoughts about new/old Lamm ML2s
Post Subject: When 6N6Ps go badPosted by Paul S on: 3/25/2007
No matter how often I go through it I still frequently get confused and disoriented when tubes go bad. In this case I have been integrating a new (passive) pre-amp and a new (tubed) phono stage into the system, including trying various tubes and new output coupling caps in the phono stage. And, of course, problems with the system coincided with testing the phono stage rather than surfacing during preamp/CD/bypass testing!
One thought I try to remember to hold is that no matter what system troubles one is presently having, the system IS/SHOULD BE capable of producing the best preformance one has ever gotten from it. Yet in this case it took me a while to "see through" the new phono stage to the ML2s to trace declining performance back to fading 6N6Ps. I actually changed the damping on my tonearm before it hit me and I remembered that I had not yet changed the 6N6Ps, because of the too-skinny pins on the new batch I had in the parts closet. Well, I grudgingly bent and cleaned the pins, swapped in the new tubes, and voila'! Too bad my present (and much-loved) fading phono cartridge is almost 5 years old, and to my knowledge it (Ortofion MC 3000 II) is no longer made... (Any ideas for a master-tape-like replacement?)
Problems associated with fading 6N6Ps were a simultaneous fading of bass and a certain reticence, along with a decided "lack of conviction" that turns the music into so much sound. In fact, it is interesting (and perhaps instructive) that I was able through various manipulations to superficially counter various problems as they arose; yet I was never able to get the music back until I replaced the fading 6N6Ps. I can't think offhand of a better illustration of the difference between Romy's concepts of "strategic" and "tactical" changes.
The moral of the story is: Do as Lamm (now) says and keep the 6N6Ps fresh (and do it before you make other wholesale changes!).
Best regards,
Paul SRerurn to Romy the Cat's Site