My Herbert external bias is reading about 20...

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Trying to bias the Herbert mk1 with external points. Here are the steps I am taking~~~>>>

Fuse out for 1&6. All volumes at zero. Power on amp, let it warm up. Put my Multimeter leads in, COM on black and the other in red. Hit Standby, but multimeter is reading 20.0 on 1&6, and the other two are reading 18.9 and 18.2.

Should I use the banana plug ends?

Any advice? I know my bias can’t be that far off, so I’m kind of lost.

https://imgur.com/gallery/43ltvCk
 
It could easily be that low, herberts bias adjustment has a huge range.

You should adjust it up to ~70ma.

The adjustments do interact with each other so go up slowly.
 
Wouldn’t that make it sound terrible, or have issues? Been like this for 3 months! The amp gets damn hot, haha.
 
It may not sound too bad, biased that cold.
Different yes.

Definitely won’t hurt anything.

I tend to like most of my amps cold , about 22 ma per tube. (44 per pair)
 
Any more help or suggestions? Should I leave it, is there an issue, etc?
 
;) Bias it up to 70ma and report back!

No one can tell if your multimeter is bad through the forum.

If your in major doubt just take it to a tech and ask them to do it.
 
I have now tried 3 Multimeter, one was a new Fluke. They are all reading the same. It sounds perfect, but I can’t help but wonder if I’m not hearing it ‘correctly’...or if I bias it up to 70 and it’s hot...then I guess I’d either lose a set or fuse would blow?
 
Like I said before our it can sound completely fine to you, even biased that low.
It’s amazing what our ears can get used to.
But most people prefer it hotter, it starts to sound fuller and warmer at 40+
Just gets warmer and more dynamic as you go on up to 70.

If your reading the meter right, 70 won’t be too hot.
Your likely going to have to run it at 90+ for a while to cause a problem with a good set of tubes. . There’s a lot of headroom built into the system.
 
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