Bias adjustment

Thank you. If I may be so bold as to ask what is a VHT bias?  And why does it have sockets? Don't I need only two leads from the meter to the bias connector [jack] on the amplifier? I'll check it out anyway. Any and all info will be greatly appreciated.

Thanks. I have a simple VOM also, but the CARY techs claimed that my bias setting was wrong and it burned out the KT-88. I know what I read on the VOM and it was reading 80 mA as it should be, but CARY kept insisting I had to send the amp back to them. I wouldn't buy a CARY PRODUCT again if my life depended on it. The techs are rude, sarcastic and think they know better than the client. Screw them!  And that's a FACT and you can post it if you want.

Thank you guys, for your input. I'll take a look at some of your suggestions. Have a nice weekend.

So many advises. I thank you all. Let me try to answer each one:
1- I did send the amp back to Cary a few days ago even tho I had no longer a warranty, because there was a clause that when I bot it about 1-1/2 years ago they were only giving me 1 yr warranty and not 3 years as the manual stated. The excuse? A special offering price on the SLI-80. I suspect they were ready to introduce the SLI-80HS and were getting rid of inventory, but I did not know that.... Well; that's neither here nor there.
I was raising the "flag" on this issue since way back within the warranty period but they always said "check bias" or "change the rectifier tubes".

2- After the techs received the amp, they claimed the bias was set at 130 mA and the KT-88's were burning up.  But why didn't the tube fuses blow? Because they found that the fuses were 8A ..... Yes, you read it correctly: 8A instead of 0.5A and that I didn't know what I was doing and it was my fault.

3- Since I bought the amp in May 2018, I never once changed the tube fuses. I was changing the AC fuse 3A slo-blo constantly, and was reporting the "damage" to Cary to no avail.

4- According to the SLI-80 manual, the bias should be set at 100 mA. When I replaced the rectifier tubes 5U4 for 5AR4's by Cary recommendations, they recommended the bias around 75 mA.  I reset the bias at 80 mA [with an analog VOM it can be difficult to differentiate between 75 and 80 mA], well within the acceptable "range".  The 5AR4's were burning up and popping the AC fuse give or take every 2-3 months.

5- I now am getting the amp back from CARY in the next week or so having paid for the maintenance, setting up, and testing it, BUT ..... I did not want to have them provide tubes or fuses as I don't trust what they say. If it works after I install the tubes and fuses, so be it. Once it blows up again I will proceed to throw it out into the ocean..... good riddance! It's not worth the stress and headaches and being told I am an idiot! Did I mention that I am a retired electrical engineer with a minor in communications and an MBA in Finances.   Oh well .... what more can I say.

Thanks for lending me your ear and advise. Have a nice weekend and stay well, wherever you are.  Richard

In reference to adjusting the bias on vacuum tubes, I have a question that no one, no manual, no tech has brought up and I am really interested to know. It is simple: When someone tests or adjusts the bias using a VOM or mA meter and the amp is ON with all vacuum tubes in place.......
1- Should the measurements and adjustments be made with NO load on the amp? In other words no speaker leads connected; no sub-woofer connected?
2- With everything connected and functioning?
Why? Is it possible one gets a different reading and how much difference if there is a load or not?  Any thoughts on this?

Oh my goodness.  If what you are stating is FACT (and I do believe you) then in both cases on my different amps I have been measuring the bias INCORRECTLY.
1- On my SLA-70 Signature amp - which weighs about 50 lbs and sits on a top shelving unit - to test the bias I need to disconnect the speakers so I can take down the amp and place it upside down to unscrew the bottom plate and then proceed to check the bias [as it is inside the amp].
2- On my integrated amp SLI-80 the jacks are on the top so all I need to do is to insert the plug and read and adjust the bias.  And I have been doing it with music playing.

In either case, neither the techs from Cary nor the service manual mention anything regarding "how to" with the exception of where the bias should be.
Thanks for your input. I appreciate it.
Richard

I accept your logic.   But wouldn't the VOM have read then 130 mA instead of what it was reading? 80 mA?

I would never buy a Cary product again. I should explain: It's not the product which is bad!  It is that after 1-1/2 years they claim there is no more warranty.  It's also that the techs do not give the customer fair and honest information nor ask the "right" questions to try to solve the issue instead of the need to ship it back to Cary. Without warranty, the cost of shipping round trip [+/- $200.00]  and repair (?) and new tubes was going to come out at close to $1000.00. If the amp cost me $3000 and after 1-1/2 years I have to put in another $1000.00 that is 30% of the value, I might as well buy me a new amp ..... and from someone more honest and transparent, totally regardless of whether I was "wrong or right".

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