I have never had any dealings with him personally but Jim McShane is brought up often as a straight shooting source for good tube solutions......
I believe if you are going to use vintage tube equipment you need to be a tube hoarder, collecting up what you can when you can and then of coarse use readily available common tubes for everyday use.
Kind of like a vintage British sportscar......you better have a everyday backup for when it rains.
You're right, I should have hoarded a bunch of Telefunkens 10 years ago when I got the preamp as they seemed much more available then than now. And I will check with Jim McShane and Doug's Tubes.
But I was hoping to hear peoples' opinions on the best brand of 12AX7 for use in McIntosh stuff.
I have recently let my tubes go for a long time (10 years) in both my Mc 275 IV and C22 and in the last several months simultaneously became dissatisfied with the sound on both (in two different systems). Prior to that, I would replace tubes more frequently just because, so I never got to the point of noticeable sound degradation. So I kinda wanted to see how long the tubes would last and if the sound would eventually go bad. It did.
On re-tubing the 275, the improvement in sound was immediately noticeable and substantial meaning the old tubes had clearly gone bad. The biggest difference is that with the old tubes, I always felt the need to to turn it up and then the amp sounded significantly underpowered, dirty and could easily be overloaded. With the good tubes, the amp is back to sounding powerful and I no longer feel the need to turn it up to use that power.
But I do have a cheap tube tester that only tests for emissions and shorts and all 11 of the "bad" tubes from the 275 still measured perfectly on the tube tester and all like tubes measured the same (e.g. all 4 KT-88s measure the same, etc.).
Point is, these older tubes tested fine but were not fine and this makes tube hoarding more difficult such that I do not trust just getting tubes that "are good" or "work" say on eBay or some such.
Also, 10 years appears to be too long and so I apparently will need good tubes every 5 years or so.
So I need to find a vendor who has test equipment that measures more parameters than my tester who can pick good used or NOS tubes from bad before I pay for them. Or I would like to find a source of new tubes that provide good sound. Getting good 12AX7s seems to the main problem. I have not been too happy with the sound of the Chinese 12AX7s in my 275 or C220.
BTW, I wish I had a test bench as I am very curious about what was going on in the 275 with older used up tubes - what was the mechanism for the poor sound and seeming lack of power? I would have liked to measure the power output to see if it was to spec.
Thx