What is so special about Phillips ECG STR387 6L6GC tubes?

[ALBATROS1234]

I got a call from one of my picker contacts who said they knew someone who had a tube organ that was going to the dump today. So, I go down last night and it looked kind of like a Conn but ended up being a 1958 Lowery, I think a D.S. I pulled the amp Chassis which had a 5U4, 6SN7 and 2-6L6GC's. The tone generators were all 6X8 tubes with a 12AX7 and 12AU7 voltage amp, the preamp had 5-1958 Lowery marked RCA long plate 12AX7s which all but one test NOS  . It also has two working Jensen P10Q speakers in perfect shape, so I snagged the good stuff. When I got home, I notice the 6L6GC's were not original and were green marked "Phillips ECG STR387" (Sylvania ?) which test basically closely matched NOS. These range from $180 to $320 per pair on Ebay and appear to be triple mica with double disc getters. Obviously, this was a huge score in general especially since it was all free, but my question is what's so fancy about these 6L6GC's?

[mresistor]

Near as I can tell they are ruggedized and possibly made for military use too. 

[ALBATROS1234]

Cool, thanks. I see I was right in guessing Sylvania made. The green lettering looked right plus I held a late 60's Sylvania up to it and the gray plates were identical in shape, size, holes, crimps etc. Plus, I noticed the bottle was taller and the top mica was a double layer. I am going to put these in a couple amps and see what they sound like tonight. Last night was a good score night.

[WimWalther]

Very nice score indeed, some old organs can be a real treasure trove of audio tubes.

Generally speaking, all of those 1980s production JAN/Philips/Sylvania tubes are held in high regard. Used to be you could buy cases of 100 6SN7 or 5814 (12AU7 type) for $5/tube. The JAN 5814 is about the quietest, least microphonic AU7 type you can find.

Many years ago I was cruising the alleys looking for old electronics, and came upon what I recall as a Baldwin organ. That thing had around 30 6SN7s in it - most were GE, with the balance being RCA, Sylvania, CBS etc.

[ALBATROS1234]

Nice, this is my 3rd organ. The 1st one was a 1959 Hammond M3 which I got for $100. It has the5U4/6V6 PP amp with 12AX7's, 12AU7's. 6AU6's etc. I ended up getting it working so I restored it and eventually it is a great working example with 12" electrodynamic speaker. I felt it was a good working Hammond and it deserved to live. I even touched up the cabinet. I will keep this one. Next, I got a 59' Conn for $50 which had like 40 Sylvania 12AU7's as tone generation oscillators plus an amp w/ 5U4 and 4x12V6's a couple 12AX7's and 12BH7's with a 12" alnico Magnavox speaker. I stripped this and kept the useful parts which amounts to the speaker and baffle, the amp chassis which had a PT and 2 OT's and tubes. This last one was a 58' Lowery which was free, and you read what I got from this. I find it is worth going to Estate sales and frequenting secondhand stores. I score lots of cheap tube gear. Recently I got a Sony R2R for $10 which wasn't a great recording device, but it had 2-12AX7's a couple 6AU6's a 6AR5, 6X4 and a couple Magic Eye tubes, plus a nice Power trannie and a small 2"x5" speaker, tube sockets, input jacks etc. I always keep a lookout for old tube gear to snap up for parts.

[WimWalther]

Sounds like you've got the game pretty well figured out. If you have the back for it, old organs and hifi consoles can have great parts. Look hard for Pilot and Ampex stereo consoles - the Pilot consoles usually contain a standalone Pilot stereo amp, and some Ampex have full component systems - pair of monoblocks, preamp, FM stereo tuner plus TT & tape deck.

I know the M3 well, had one for many years. Kind of a "baby B3", as they do use a B3 tone gen and have a limited percussion effect. Like all old Hammonds, they sound wonderful - and play good & loud.

[ALBATROS1234]

Yes, my 59' M3 has the same tone generators and vibrato scanner, the keyboard has one octave less and there are no presets but the same drawbars and all. That thing gutted would make a killer amp, but I can't bring myself to desecrate a Hammond. The Conn, Lowery etc are a lower end product IMHO and I don't lose sleep pulling one apart. I was tempted because I saw this guy online pulled the vibrato scanner our of a Hammond and converted it into a guitar effect. I chickened out though.

[WimWalther]

Despite having owned one, it was many years ago and I was never very familiar with the Hammond tech.

Is the vibrato scanner the round, soup can sized device that sits in the upper part of the organ case?

Also, does your M3 have the octal or miniature tube based electronics? Or were the octal type only used in M2? Come to think, I know I still have a complete B3 tone gen in the attic, and I may have a set of octal electronics as well.

Need to check on that stuff.

[eleventeen]

I used to hunt organs, and to be sure they can contain loads of good usable parts, though you'll probably find that most of the caps are 200 volt. Like you, I am reluctant to tear apart a Hammond, any Hammond. Lowreys and CONNs are fair game. If you can just pluck the tubes, that's pretty good, if you have to haul the whole thing, they really generate a lot of waste crud, though sometimes I have used bass pedals if they are wooden) for good stuff. Even though most of them are remarkably poor instruments, I still feel a little guilty stripping down an organ, even if it's a non-working CONN.

[ALBATROS1234]

I agree fully, I won't scavenge my Hammond even though I can't do more than bust out a few basic chords. This M3 amp off the top of my head has an AO-29 amp which has mini tubes, other than the 5U4 and 6V6 pair of course. Oddly it still has a very nice working 12" electrodynamic speaker. I have a guitar cord which I adapted to have one end as two alligator clips and I clipped into the exterior backside screw terminal strip and played directly through and the amp, vibrato and speaker which was chock full of warm tubey goodness. Note, the speaker is very unique sounding as I also rerouted the amp through a 50's Alnico Magnavox 12" which sounded quite good, but those electrodynamic speakers have a bit of something different which you can't put into words. It was inefficient in that the volume was fairly low, but it has this really warm smooth tone that you can feel as much as hear when strumming "edge of breakup" chords.