Help with re-tubing an ARC VT100 MkII

Louisl, did you ask him about the input tubes? Is there any bias adjustments?

I have a VT50 and the only adjustments I have to do is the "Output tube Bias Adjustment" for each channel. No big deal.

The owners manual has a section for how to....Have you checked it out?

Jea48

I retubed my VT100 MKII using the instructions above from Collins. A matched octet(8) from Upscale audio will cost about $240. A set of 8 low noise input tubes 6H23 (6922) will cost about $200. Total $420 plus shipping. You may want to speak to kevin Deal at Upscale. You must use input tubes with close tolerances.

that's a lot of money they charge, these ARC guys. I am considering this amp myself and curious what the outcome of this will be as far as what you can do yourslef vs what has to be done by ARC. As far as buying tubes for my ARC LS-15 pre, I had great experience with www.upscaleaudio.com
Kevin really knows his stuff and their tube matching is very reputable. So far the tubes I got from Kevin made my pre-amp sing and I tried a lot of tubes from lots of different stores. You may actually save some money with UpscaleAudio vs. ARC. Just a thought.

Jea48...yes there are bias adjustments for the input tubes as well as the output tubes.

Gmorris and Rlips...thanks for the input. I have the Collins site and have printed it. The biasing of the input tubes however, looks a little difficult. Any further thoughts?

Audphil1, thanks also, I'll give Kevin a call.

I just went through Collins site.... I am sure glad I bought the VT50.

I can not speak for the VT100, but for the VT50 for about the first 10 to 50 hours of tube burn in, for the EH6550 power tubes, I reset the bias trim pots about 6 times , a pain in the butt. I did not notice if Collins mentioned anything about readjusting bias pots after burn-in of the new tubes.

Maybe others who have posted can respond on readjusting bias after burn-in.

You may want to check with ARC. Is ARC pre-burning in the tubes....

Jim