TUBE BIAS, socket to me!


BIAS: (I'm starting from zero understanding) 

I have never measured/adjusted bias in the 3 tube amps, 3 tube receivers, and 2 tube preamps I have acquired over 47 years. I just switched my current Cayin from 6550's to KT88's. Adjust bias? Adjusters inside, scary electrocution warnings. I could pay someone else to do it, i.e. Steve at VAS 1 hr away in NJ, soooo, 

What really counts? (personally I don't care about either heat or life, but would like to understand)

Heat?
Life?
Output stays Matched when adjusted?
Acoustic Performance?
_________?

Over the years, fronts off, bottoms off, I hose em down with contact cleaner/lubricant, compressed air, all controls and switchers, any adjusters, swish full spin back and forth. Kill any spiders, look for, replace the rare burnt resistor. 
Then leave any adjusters (whatever they are) in the middle position, button it back up.

Two tube testers, my big hickock always agrees with small portable one, test strength, shorts, matched strength old and newly purchased. Large collection of NOS, used. Often used test essentially same strength as new ones.

When they go, it's usually a short.
elliottbnewcombjr
@lewn,

The statement below was from a positive feedback article about the MX110Z that Elliot was gracious enough to provide us.

"Like me, after living with the MX110Z for a while, you may wonder why all modern preamplifiers don’t include FM tuners and equalization controls—they’re great fun! Also, tell me, is there anything even remotely comparable to the vacuum tubed McIntosh MX110Z currently available today at any price? No, which is a pity."
http://www.positive-feedback.com/Issue77/vintage_mcintosh_experience.htm

@ elliottbnewcombjr,

Talk about a labor of love and patience! You kept the same preamp and kept it working after all these years. The money you've saved and knowledge gained on that unit, from not having that dreaded disease of upgraditis...Bloody brilliant if you ask me. 

As an Architect, whose path went the way commercial interior designer. I'd love to hear some of your stories on acoustics where the materials used were passive and maybe active in a room/hall you designed with the customers acoustic wants in mind. 

tyray

I just bought that used McIntosh mx110z tube tuner/preamp in June 2019, a purchase of love but not a long held piece. I sold my McIntosh SS Preamp C28 and McIntosh SS2250 to switch back to tubes.

I have avoided upgrades fairly well, primarily because I have been lucky to both inherit great stuff and been given some great stuff. I have given a lot of stuff to others as well. Met Bill here last year, we swapped my Fisher 800C receiver for his Mitsubishi Vertical TT, LT-5V which I revived and plays in my office system now.

I designed Corporate Offices, New Headquarters, Relocations, Renovations, for 47 years: NYC, Phila, Wash DC, Chicago, San Fran, Toronto, hired my own consultants, did everything soup to nuts.


skypunk

you haven't been paying full attention, I need 16 ohm taps, the only Cayin with 16 ohms is the original version, with internal bias adjusters.

Raven looks nice, but no 16 ohm taps
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