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VTL MB-450 Bias adjustments

I've biased my VTL MB-450's many times over the years, but I've only assumed that the bias pots correspond to the tube placement left to right (or right to left). That is, the 1st pot on the left adjusts the 1st tube on the left, 2nd pot to 2nd tube and so on. Since the tubes are staggered you have to move up and down as you go across, but it would be something what I've done below, the first row represents the pots, the second and third tubes. This might be in the manual, but mine may be in a box in the attic.

Does anyone know if this is correct, or if not what the correct order is?

  12345678
  2  4    5  7
1  3        6  8

128x128bmcleod
bmcleod's avatar
bmcleod OP
57 posts
 
Mine are the Series 1, or just the MB-450.

It’s actually one drawing, the top straight line of numbers represents the pots, the bottom two lines are the tubes.

So you’re agreeing that (for instance) the number 6 pot in the top row adjusts the bias on the number 6 tube in the bottom row?
fedie
61 posts
 
Yes correct , I own mb250 mono block, according to bea Lamm from  vtl.  I had the number 1 tube go out and the number 1 bias pot . had no reading ,until I put a new tube in . 
bmcleod's avatar
bmcleod OP
57 posts
 
For the record, I found the manual today and there is a diagram of exactly what I was looking for!

Indeed it is as I laid it out above, tubes are numbered from L to R, Bias Pots, and measurement points as well.

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