lewm
thanks for taking the time to respond with all that information.
Sonically, what are your experiences?
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.
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.
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- 91 posts total
bdp24
thanks for the reference, I'll search for his name, his recommendations. Any personal experiences? |
tomic601 this mx110z is the best purchase I ever made, chosen based on this review http://www.positive-feedback.com/Issue77/vintage_mcintosh_experience.htm If it died, I would instantly buy another without considering anything else. The mx110z has gone up in price a good bit since I bought mine 1-1/2 years ago. ............................. this is just a long winded story now, nothing to do with bias. The mx110z tuner: Richard Modafferi is quoted as saying something like "there is nothing I can do to improve it". https://www.audioclassics.com/mods I have a lot of respect for him, I met him once, very friendly. I bought his JSE Infinite Slope Model II speakers when he was in business making them himself. They had his two patents. Joseph Audio still uses his infinite slope crossover in a few models. The most accurate speakers I ever owned, the only ones I ever wanted after going to many NYC audio shows. Instantly wanted them! I got lucky, my friend Phil at Leonard Radio, ground floor of my building on 44th street (former Hammond Organ Showroom) knew I loved them. He told me senior salesman Ray had taken in a pair on trade with burnt tweeters for $700. (new $5k a pair then). Phil and I ganged up on Ray, reminded him I had given them some good advice when they were planning their renovation (I'm an Interior Designer, more like Interior Architect, specialized in Corporate Headquarters). Ray says "I'm gonna replace those tweeters and sell them for a lot of money! I said, no, I'm gonna replace those tweeters and keep em. Phil pushed him, he finally agreed. I rolled those suckers out, up the elevator, hid them in the AC room in case he changed his mind, got em home that weekend. Now, what the heck to do with the big boys downstairs? I say to Donna, the attic is too hot/cold; the crawl space too damp; they wont fit through your mothers cellar door. Donna says, "what about the bedroom, I love those speakers". OMG, I love you!!! Those JSE's instantly took over Harvey's on 45th street. Until they didn't. I don't know this personally, and still have utmost respect for Richard Modafferi. My friend Wayne, who sold a lot of them, told me JSE's mistake was making the enclosures himself, he could not keep delivery schedules, delays so bad, wealthy customers mad, Harvey's dropped them. After years of them, using McIntosh SS MC2250, I decided to give the JSE's to my son and go back to tube amps, the Fisher 80z's and the big boys I use currently. Still using McIntosh SS C28 Preamp. Back to LP, I was not happy with C28's phono, I actually preferred the one built into the AT120TT I had. Had McIntosh Factory check/restore it, still preferred the AT120. I decided to get a tube preamp, researched, found the mx110z which includes a tube tuner. Existing Carver Tuner was terrific but the mx110z tuner just sounds so involving. Carver Tuner is now in my office with the Carver Cube. I got both from Harvey's used shelf. Wayne called me when he knew a trade in piece was coming out of the service dept. mx110z Phono: Wonderful, I can't imagine even thinking something might sound better. |
Elliott, if it has those tiny little pots they make adjusting tools for that. I always called them "tweakers" LOL, Radio Shack sold a set of 3 for just a couple of bucks, made of plastic. If your going to do this, just make sure that the power is off when you attach your insulated clip leads. Use your meter set to DCV and check the PS caps to see how long it takes them to bleed down. Most PS have a bleeder resistor across the caps that will discharge the high voltage in just a few minutes. Not a bad idea making an insulated tool, easy to slip and make sparks/do damage. I bet Greenwood has the proper tools, do I really need to give YOU an excuse to go over there? LOL. BillWojo |
- 91 posts total