Help Identify a Sylvania NOS 6SN7-GT Tube.

asindc

asindc

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I posted this over at head-fi.org in a thread titled "The 6SN7 Identification Guide." Here is a link to it: The 6SN7 Identification Guide. The OP did an outstanding job of compiling the information. After reading the first few posts, I still need some help identifying a tube. I have a Cary SLP-05 that I need to re-tube. I've already bought a mix of tubes to roll, but I figured I would try some of the tubes the seller of the 05 sent along with the preamp that I had put aside because they weren't a matched set of 6 or 4. Of the two tubes in the first pic, I'm quite sure the tube on the left is the Sylvania 6SN7GT "Bad Boy." It is described in the first post of that thread as such:

Sylvania 6SN7GT 1952 “Bad Boy”
Also JAN-CHS-6SN7GT
Made only from late 1951 (‘1-48’ examples seen) to 1952. Differs slightly in construction from ‘regular’ Sylvania rectangular top mica 6SN7GTs. Re-labeled bad boys are known to exist.
Base: black, green labels marked ‘2-XX’ (where XX is the week of the year)
Glass: clear
Plates: black, T-plate with 3 holes per plate
Getter: bottom, foil, flashing can extend up to 1/3 of way up tube
Top mica: rectangular with 3 spikes on each of the shorter edges
Click to expand...





As seen in the next two pics, it is labeled "JAN-CHS 6SN7GT" and it is of 1952, week 3 vintage.





The tube on the right in the first pic is the one I'm not sure about. At first, I thought it was the Sylvania 6SN7GT, version 1, which is described as such in the first post:

Sylvania 6SN7GT version #1
Also JAN-CHS-6SN7GT
Identical to VT-231s except:
- Green printing seen on black base; white labels are much rarer.
- Made in the 1950s.
- Flat plate versions exist across all year of make (very rare).
Base: black, green labels, triangular Sylvania logo with ‘lightning bolt’ through logo.
Glass: clear
Plates: black, T-plate, (or rarely, flat black plates) with 2 holes per plate
Getter: bottom, foil, flashing can extend up to 1/3 of way up tube
Top mica: rectangular, (flat plate versions have round top and bottom micas)
Other significant features: when seen, date codes are vertically arranged (from top to bottom) ‘YWW’ with Y underlined. Y = last digit of year, WW = week number of year
Click to expand...



As can be seen in the next two pics, this tube has three holes in the plates instead of two and the year date code is not underlined. The production date is 1952, week 13. It seems to match the description is every other way. However, it also closely matches the description of the Bad Boy, except that it is slightly taller and has the lightning logo.





I apologize for the sideways orientation of the pics. Any thoughts as to what these tubes are will be appreciated.
 
the tube on the picture is what's called Bad Boy Svetlana 6SN7GT - great sounding tube. Actually Bad boys were only produced in 1952 (to my knowledge) and never carried CHS marking. So you have the real deal. :)
 
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