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Matching KT88 Tubes?

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petertub

petertub

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Joined 2015
tubular-well.se
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radiosmuck said:
Four KT88 tubes measured on a B&K 707. 80/120, 80/120 and 82/120, 83/120
Could they be described as matched pairs?
Thanks
Click to expand...
Not by the information shown so far.
What voltage is the measurment done at ?
Which working point is the measurment done at ?
On that working point : how much current is drawn?
what Gm does the tubes hve at that working point ?

What voltage and workingpoint is the amp using ?
 
R

radiosmuck

Banned
Joined 2012
petertub said:
Not by the information shown so far.
What voltage is the measurment done at ?
Which working point is the measurment done at ?
On that working point : how much current is drawn?
what Gm does the tubes hve at that working point ?

What voltage and workingpoint is the amp using ?
Click to expand...

I purchased the GEC tubes over 30 years ago with the idea of substituting them in an EL34 amp but the tube sockets were too close together.
I had the tubes tested after I purchased them but they ended up in a box on a shelf and forgotten, after I lost interest in tube amps.
I dragged the tubes out last year and took them to a technician who re-tested them and wrote down the results above.
My idea is to offer them for sale on an internet auction site where I've learned that matched tubes are a little more valuable.
 
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