How do 6SN7WGT vs 6SN7GT differ?


I have Cary WE300B SE monoblocks and a Cary SLP98P preamp. I have been purchasing back-up tubes to stash away for the future. I am confused by the broad number of GSN7 tube types available, in particular the difference between N.O.S. 6SN7WGT and 6SN7GT(A/B)tubes. Are they simply interchangeable?

I use high dB horn speakers (103dB sensitive), so I am concerned about tube noise. I have teflon tube dampers on all tubes, and these, I believe, help with microphonics.

Thank you.
cardiackid
Yes the W denotes military..

From a purely technical standpoint the tubes ending in GTA, GTB can handle higher voltages (max of 450 volts or 5 watts per section) than a GT can (max 300 volts or 3.5 watts per section). Therefore the GTA/GTB will run cooler.

The GTA/GTB were made for televisions commerically, and for military probably a television type display and other higher voltage applications.

If you want a quiet tube then try a 5692 tube. A 5692 tube is rated for up to 275 volts or 1.75 watts per section.
Oh.... the most popular 5692 tubes are the RCA Red Base and the CBS Hytron. If you find any other branded 5692 tube with the same color Red Base, then it is the RCA tube. RCA made some for a few other companies.

The 5692 will generally have the lowest possibility for microphonics.
There are more points to these. The WGT is the highest voltage handling plus it has an 11 second warm up time. This prolongs tube life all around. I happen to have 8 NOS CBS 6sn7GTB tubes if you need.
Emery
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