Bias adjustment

I’ve measured my Cary with, and without, a signal. It was the same. I alway check without. I wanted to see if it could cause the reading you had. Mine was fine, so was your.. You do need to recheck at least a few times, back and forth.
WHY?. In a stereo one side will change the other, until they are both within 5% or so. Go back and forth a few times.

I also checked a pair of older VTLs same, and a Citation II. No change in the bias, I set a high, and low capture on my meter. Never more than 5-7ma from zero volume to 50% volume. All six amps, same.

How do you bias? UNIT OFF, turn the bias down CCW. Insert your 1/4" jack. Power up the unit, warm 10 plus min or so. You can leave the input signal off if you like. Bring up the bias slowly CW. Power down, move your 1/4 inch jack, to the other rail, power up and bias.
TWO or more times. New tubes, recheck see if the new valves are holding a bias...

I just had a bit of a tiff also with Cary. I ask for a schematic, hand written, or partial for the hexfred upgrade. Didn’t ask where it goes, or to hold my hand while someone else does it. I asked TWICE. Just ignored the request.

I’ll buy a plane ticket and knock on a door, no problem for me..I’ll get my schematic. If I have to draw my own, I’ll post it for ALL to see. There will be no secrets then. EVERYONE should be able to get technical information on equipment owned by them..Especially a schematic.. That schematic should reflect the safety or lack there of built into unit. It should reflect upgrades also...

Regards...

Hello oldhvymec. Yours has been probably the best and clearest explanation of all the "advices" I've had. I REALLY thank you for taking the time to explain the bias process.

I've had a similar issue with Cary when my old SLA-70 Signature ran into trouble some years back. They would not supply me with a schematic at all saying it was "obsolete" and they do not keep old schematics. None of this should have happened if they had a bit of honesty and transparency. I'm sure that Dennis Had (?) in his days never had issues like that. It's a shame the company has changed owners. Such is life.
Thanks again for your help. Sincerely, Richard

I just had a bit of a tiff also with Cary. I ask for a schematic, hand written, or partial for the hexfred upgrade. Didn’t ask where it goes, or to hold my hand while someone else does it. I asked TWICE. Just ignored the request.

I bought a case of Coca-Cola and called up there head office and requested the formulae and was also ignored.  

+1 @testpilot   at what point does a consumer have a legal or ethical right to a firm's intellectual property just because they purchased a product?

How on earth are you guys measuring bias while running a musical signal? The bias moves up and down continuously while the music playing. It must be idle to measure it accurately.