[sam6550a]

Care to explain for us clueless folks?

Getter flash is generally silver in color. The getter flash on the subject 6550 is brown or tan, indicating that the tube was driven hard, the elements got very hot and out gassed, which the getter flash tends to adsorb. As it is depleted, the silver color fades, This tube is probably gassy, exhibits heater - cathode leakage, or has low emission, but is certainly close to the end of its useful life.

 

[Slade01]

Getter flash is generally silver in color. The getter flash on the subject 6550 is brown or tan, indicating that the tube was driven hard, the elements got very hot and out gassed, which the getter flash tends to adsorb. As it is depleted, the silver color fades, This tube is probably gassy, exhibits heater - cathode leakage, or has low emission, but is certainly close to the end of its useful life.

So are the strong test results that this tube claims to have and the brown/tan getter flash color mutually exclusive?

 

[Mr Trev]

Getter flash is generally silver in color. The getter flash on the subject 6550 is brown or tan, indicating that the tube was driven hard, the elements got very hot and out gassed, which the getter flash tends to adsorb. As it is depleted, the silver color fades, This tube is probably gassy, exhibits heater - cathode leakage, or has low emission, but is certainly close to the end of its useful life.

Ahh, I guess you're referring to the brownish spots on the sides not the top.
Thanks for splaining.

 

[sam6550a]

So are the strong test results that this tube claims to have and the brown/tan getter flash color mutually exclusive?

Since the only data presented is one number, which I surmise is transconductance, I have no way to tell. Tung-Sol [the original US company] specified the transconductance as 9000 at 87ma plate current and 11000 at 140 ma. Othe factors, however, also affect tube performance. I do have 3 6550s with brown getter flash in my tube locker, and all 3 show heater-cathode leakage after 10 minute warmup.

 

[sam6550a]

Ahh, I guess you're referring to the brownish spots on the sides not the top.
Thanks for splaining.

Yes.

 

[bcowen]

So are the strong test results that this tube claims to have and the brown/tan getter flash color mutually exclusive?

Never trust that seller's test results. Although she (he?) has a very nice vintage tester (the Triplett 3444A is quite nice), it's either not calibrated, not used correctly, or the test readings are a flat out lie. I've bought two different tubes from her, both claimed as testing at NOS levels, and both barely at minimum values when tested on my Hickok (that IS calibrated and used correctly). I was refunded both times almost immediately with no request to return the tubes. Neither were expensive, but a no-questions-asked refund with no return required tells you something in and of itself, IMO.

 

[JKDJedi]

If you like accuracy across the sound spectrum that is not bass heavy or mid loaded I like Melz 1578’s coupled with Tung Sol 5998’s or Chatham bottom getter 6AS7G’s. I can get more specific on 6SN7 equivalents but they do not always play well with Chinese amps of this caliber.

The tubes I am thinking of cost more than your amp but I have done a lot of experimenting.

The cats meow ..

 

[jonathan c]

The cats meow ..

Speaking of which….is Finnegan still supervisor and SVP of quality control at Palad Industries, Inc.?

 

[Paladin79]

Speaking of which….is Finnegan still supervisor and SVP of quality control at Palad Industries, Inc.?

I am taking a break from electronics so Finnegan is relaxing with me. He still follows me around but is not allowed to go along on trips to help my renters and such.

 

[jonathan c]

I am taking a break from electronics so Finnegan is relaxing with me. He still follows me around but is not allowed to go along on trips to help my renters and such.

You wouldn’t want him to get any ideas about “squatters’ rights”….

 

[HTSkywalker]

If you have a Darkvoice without modifications it is wise to stick to such tubes. I get so much hum in a standard DV that only a few tubes might work and quality of sound goes out the window.

I second that especially on the 110Volt version, the EU 220V version is not that delicate though.

 

[HTSkywalker]

My likes and dislikes are pretty specific and while I own a DV I need to modify it before I could listen much.

Been due long time now

 

[HTSkywalker]

I need to get back to my DV but right now my interests lie in art history and other areas.

Sounds a major deviation, we won't like losing you around . at this age some other guys may buy a Harley too

 

[HTSkywalker]

i know this is leading a bit down the tube rolling rabbit hole. for rich, warm, smooth sound, i'd look for an RCA Gray Glass 6SN7 (or VT-231). Or the National Union Black Glass 6SN7GT. I'm not sure how they price these days -- they used to be reasonably priced before. Or sometimes you can find these tubes - just rebranded with a different name and sometimes you can get a bargain that way as well.

RCA Grey glass are a good all-round performers in a DV

 

[HTSkywalker]

I wasn't far behind, we had a slide rule in the house but it was my mother's and I typed all of my papers on an electric typewriter. Computers at the time were rare and only used for looking up library reference materials or teching the mundane programming languages of the time, i.e. Cobol, Pascal, and the dreaded FORTRAN.

Used all those languages during my Uni years