3 matched sets. 2 'bias sides' which go with which


Ok I have a Bass amp. A 10+year old Ampeg SVT 2 pro. See links below... The amp has been losing its power and clarity, so it's time for a retube. I decided on Tong-Sol 6550's for a number of reasons (mainly bc I can get them at factory cost). Now I was able to order them as three matched sets. The amp has two bias controls. I'm guessing each one controls three tubes. So that means I have to split up a set to make two groups of three. On the boxes there are stickers with 'matching' data on them. It reads as follows:
1. Ip:54 Gm:6,900
2. Ip:54 Gm:6,900
3. Ip:54 Gm:6,300
4. Ip:54 Gm:6,300
5. Ip:43 Gm:6,300
6. Ip:43 Gm:6,300

Basically when looking at the amp from the rear, which tubes go in left to right? I'm guessing 1, 2, 5 and then 3, 4, 6. That puts the IPs so that one tube on each side runs colder (#5 and #6). Or should I do it differently, maybe go by the Gm.

Help me.
Thanks in advance.
Ryan

User Manual and basic info: http://www.ampeg.com/products/pro/svt2pro/

Schematic drawings: http://www.prowessamplifiers.com/schematics/images/ampeg_svt-2_pro.pdf

Pictures:
http://www.valvoletamburi.net/obama/images/ampeg-svt2-pro.jpg
http://www.hux.com.au/Soapbox%20Items/Gallery%208%20Items/Ampeg%20SVT-2-Pro.jpg

As you can see in the pictures the power tubes are arranged in a \/\/\ shape. From the rear, left to right, lets say the tube positions are:

AC E
\ / \ / \
B D F
holle8e3

Showing 1 response by isochronism