Valve amp bias kits

[Tee]

Does anbody have any experience with amp biasing kits for output valves? I saw one on [url="http://www.hotroxuk.com/bias-tool-manual-6135-0.html"]hotroxuk[/url] and thought i'd look into the idea and see if it's worthwhile.

[The Burpster]

I like the look of this companies kit.....

[url="http://biasking.com/"]http://biasking.com/[/url]

One of them is 'on my GAS list'

[Tee]

Thanks. I take it you can actually [i]adjust[/i] the bias with that tool, rather than just monitor it?

Edit: ok, read the manual. it's just an indicator.

Edited January 7, 2009 by Tee

[The Burpster]

I guess you've read it, but the bias of valves changes with age.... some amps sound better with them slightly out of balance but most (especially those with lotsa valves) sound and work better with balanced bias.... so effectively you swap them around to get pairs with equal values.

[umph]

i've got one it saves alot of hastle of opening everything up and getting inside the amp to check the bias, makes checking the bias a piece of piss

[Tee]

Which do you have umph and how does yours work?

[umph]

i got the dual one from [url="http://www.amp-head.com/"]http://www.amp-head.com/[/url] it works by measuring the voltage from the cathode so you read that in MV and adjust the amps bias till you get the desired bias