How to turn your Express into a Rocket (actually an ICBM)

[tejastubes]

Wondering if any of you express owners have ever tried the Bendix 5992 (super beefy overbuilt "Red bank" version of the 6V6 tube)? I believe it was actually used in ICBM's. Let me know.

I know the express can take the 6V6 tube so it would be interesting to the hear this particular one in there.

Joshua

[dartanion]

Send me a pair and I'd be happy to give them ago in one of my Express builds

[tejastubes]

Thanks! 2.5 Benjamins on those per pair,,,I may have to wait until mine is completed ( I am drooling as i wait) unless there is a brave soul who wants to do some taste testing.

Most of the people who buy these are audiophiles who own BAT pre-amp units which takes a pair of 6V6 and they tell me the low end is huge and sound stage is thick and full. (like a juicy steak) hence I used the word beefy.

Joshua

[Richie]

not to get mixed up with 5932.

[tejastubes]

Yes the 5932 is a mil spec version of the 6L6

[Abstract]

Where could one find a set of these tubes?


Besides the obvious "In an old ICBM, silly".

[tejastubes]

I have them available on my website. They are obviously pulls (from ICBM's but are tested and matched for current draw on two different machines.

Joshua

[dartanion]

$250 for pulls

Does that come with the waterfall gal?

I have no problem finding great sounding RCA black and gray pulls for less than $10 a pair. Do you think they really sound 25x better than an RCA Black Plate 6V6?

[tejastubes]

Never heard them in an express. Very few produced of the 5992 the rca was mass produced.

[dartanion]

Hey Joshua,

I understand that there were very few made, or that there are very few to be found these days. They're probably tons of them locked away in a military warehouse somewhere.

My point being that audiophiles may be willing to shell out that kind of cash for a pair of beefed up 6V6s that'll be babied, whereas us guitar guys probably won't as we tend to abuse the crap out of them. I can buy loads of used RCAs, GEs, etc.; for much less and still have great sounding tubes and not worry about toasting a set of rare high buck tubes.

I am sure these are fantastic sounding tubes and are probably great in an Express. However, I can still get great NOS EL34s for less than half that price.

[tejastubes]

Ok I undertstand but red bank tubes are different. I will post a picture of them. Also, many guitar may have different ideas about money and tone but I respect yours.

[Firestorm]

These (and the 5392) were definitely the height of military excess. 10,000 hours life expectancy; tested to 80,000 feet altitude; had to be able to withstand twenty 500G impacts and 100 hours of 50G vibration at 18 cycles. Oh, and be boiled in water for three minutes, then plunged in ice water. I was always put off by the 300VDC "maximum" plate rating. That's the old rating for the metal 6V6 which this tube replaced and supposedly is not the max voltage at all, just a familiar voltage the Air Force engineers would be comfortable with. But at 2.5 hectobucks a pair, it would suck to fry 'em.

[tejastubes]

These (and the 5392) were definitely the height of military excess. 10,000 hours life expectancy; tested to 80,000 feet altitude; had to be able to withstand twenty 500G impacts and 100 hours of 50G vibration at 18 cycles. Oh, and be boiled in water for three minutes, then plunged in ice water. I was always put off by the 300VDC "maximum" plate rating. That's the old rating for the metal 6V6 which this tube replaced and supposedly is not the max voltage at all, just a familiar voltage the Air Force engineers would be comfortable with. But at 2.5 hectobucks a pair, it would suck to fry 'em.

Yes, the 5992 can withstand alot. I ahve always wondered if they can withstand alot more on the plate even though they are rated there. We will see when my express is completed!

[dartanion]

So if used 5992 are $250/pair, what does a true NOS pair sell for?

Point being, while these are "great" tubes, there are hordes of good 6V6 pulls out there that'll probably sound just as good for a whole lot less. Granted, when it comes to tone, I usually would plunk down that kind of cash it indeed had distinct advantages over what is currently available (read EL84s here for sure). I am a big proponent of NOS and good used tubes, however I would be hard pressed to spend that kind of cash when known NOS supplies are still decently priced for alternatives.

I wouldn't mind trying some these out for a taste test in my 6V6 based amps and my Express type builds, however $250/pair is a bit steep for used tubes IMO.

[CaseyJones]

had to be able to withstand twenty 500G impacts and 100 hours of 50G vibration at 18 cycles.

I've heard the "500G" impact hype bandied about, it's probably a bogus spec. "500G" impact means the tubes would be travelling at a tremendous velocity (17,000 mph escape velocity?) and then they'd stop abruptly. It's too bad we scared off Gary "Rocket Science" Moore, he'd have the formula to describe the behavior of glass enduring a 500G impact. I'm thinkin' silica powder.

The published specs were likely intended to fool the Russians. No worries, the Russians figured out how to make aerospace quality tubes and killer PIO caps. Too bad they don't have an incentive to build anything that good now.

The correct spec is probably more like 50G acceleration. You'd expect that in an ICBM application. 500Gs is a frickin' crash. What, the tube is supposed to function 10 milliseconds after the rocket impacts and before the warhead explodes?

Know that Peter Gabriel album cover with the guy with the gnarly face? That was s a military experiment on a rocket sled to see how many Gs the human body could endure. Know when yer Mum said, "don't make faces... your face will freeze like that"?! Apparently Rocket Sled Guy was some screwed up when they unstrapped him.

Mil spec gear gets torture tested on a shaker table. I can't imagine a table capable of 50G acceleration @ 18hz, 100 hours of that would take the damn machine apart and probably pound holes in the concrete floor.

Hey, I got it... stick the tube on top of the die in a Minster press and bang out fenders three shifts a day until some time next week.