Besck of luck with your VM!!!

Reinstalled Bias tool inline and 2 out of 6 tubes biased up. Good to go.

OK I have taken the dual bias tool out of the equation. The readings now are KT66 1=456 Kt66 2= 256. This follows any KT66 I put in. tube 1 is high and tube 2 is low. I only have 1 trim pot. this unit was made April 2008 and was bought as new from MF. It has functioned up to now very well.

I failed a KT66 in my Vintage modern 2266C. I have a supposedly matched quad of valve arts and a supposedly matched pair of Groove tubes KT66HPz. None of these tubes are matched at all, when rotated in/out with the dual bias tool inline. probably should take it to a pro. Thanx much for your reply, b...

What you see are the only identifying marks on these tools.

Anitoli, Are you affiliated with SRS? You say 2 of "our" mV probes is thereason I ask. Here are pics of what I have.

Does anyone have the instructions for an SRS Biastool PVT, and the SRS Dual bias tool?

May your wife rest in peace and may you find solace in your life. Good luck Sir.

cannot open link.

What tubes are in it Sigi?

Sunday night - Savoy Brown started that one. I have always love that tune. from the muchly unknown looking in album.

Also use the controls of the guitar, this amp is designed to work with input of the guitar controls to enhance the playability of the amp. If playability is the right word.

I wonder, if the Class 5 is so bad, why aren't any of those people working for Marshall? Our own SteveD, I guess had a major hand in the design of the Class 5. And as we all know he DOES work for Marshall and not in the shipping department.

Early 4100 had EL34z and after 1996 I think had 5881 tubes. Mine is a 96 4102 100 watt combo and it has 5881z in it.

Thanks for the info guys.