Whew! Best case for SS I ever heard.
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Too, too, much! ROTFLMAO. Talk about getting educated the hard way.
Try calling the techie that fixed your amp. He apparently knew what the bias should be. Next time get an amp with auto bias circuits - that should work for you SS guys.
BTW I showered, I'm all dressed up, and still no one wants to go to dinner with me. :-)
P.S. One was just listed in an auction on Audiogon. It closed with out bidders on 6/25/05. The lister put his name and phone number in his ad. Perhaps you can just give him a call. If you can't find this in Audiogon closed auctions, its on "Google".
I don't have the same tube amp likes yours But the idea may help. My tube amp are a pair of Heathkit W4-AM (link here http://www.heathkit-museum.com/hifi/w4-am.shtml). I recently did the bias by myself. It was required few things as follow:
- a flat screw driver.
- two mono audio male connectors with two lead wires on the other ends to measure.(connector looks like the one frequently see on the micro phone end, 12mm diameter?). I bought this cable interconnect from radio shack 1 foot lenght for around 3 bucks then cut them in half.
- Two DVM meters ( I have one and borrowed one from friend)
*If you have only one DVM, it works too but you have to ON/OFF and moving back and forward to adjust.
The way I bias my tubes as follow:
- I stripped the cut cable interconnect ends to have two lead wires to connect to DVM. this DVM is set to measure current in 100 mA or higher. Do the same with the other cable interconnect and DVM.
- Since it is measuring DC current I turned off the amp, plug the other end of interconnects (audio connectors) on both female connectors on the amp.
- Watching on both DVM screens while turning on the amp. If any DVM shows negative current I turn the amp off then switch the wires. This step may not need but I like to see positive flowing current.
- In one of my amps initially one showed 39 mA and other showed 43 mA. I used flat screw driver slowly turn the pot to where both DVM indicated the same reading. It ended up around 41 mA on DVM screens. The other amp ended up around 44 mA. I refer letting the amp stable (warm up) for few minutes before adjusting.
- It's done.
IMO to bias tubes means to set the quiet current (pause the music during biasing)of both tubes as close as the same to reduce distortion and longer life for tubes. If you are noted the sound is better after adjustment or at least you know your tubes working in the right setting.
Excellent story, Nrchy. Not only informative, but both fun and funny. Bravo!
While perhaps a coincidence, this Albert Porter character you've conjured up for the story seems eerily familiar. Could it be.............. Nah, couldn't be...
As an aside, may I offer that if you would like to contact the factory, my wife is from China and can take care of the language barrier.
Nrchy, on a serious note, you really should find out exactly how to set the Power Tube bias voltage recommended by the Amp's manufacture. I have an Audio Research VT50 Power Amp and the bias voltage setting is 65mv for the 6550. If the bias voltage is set too high you could damage the KT88 tubes. You may want to post a question on AA in Amps. Have you tried a search on Google for a USA printed owners manual.