Topic: Tubes - Telefunken ECC83 / 12AX7

[SmokinJoe]

I just found a box of tubes in some stuff I inherited.  The guy I inherited this stuff from... he was a musician, and audiophile of sorts.  I can imagine him pulling these from old amps or something and saving them.

How do I tell if these are the ones that are highly sought after?  I know there are "smooth plate" ones and "ribbed plate ones"...  I did a google search, and looked at some pictures, but I can't tell what I'm supposed to be looking for.  I do see some latitudinal bumps in the plates... I guess those are the ribs?

Another think I guess I'm supposed to look for is "Diamond bottom".  I guess this is it, huh?

If they are valuable, what is a good way to get them tested, and maybe even match so I could sell them in pairs?  I'm assuming the machine at Radio Shack (do they even have them any more?) ain't gonna cut it.

[hippiebob]

Post a thread on The Gear Page. They can tell you everything you'll ever want to know about tubes and more. I can tell you that you have some highly desirable tubes if they test good.

[ArchivalAudio]

gives a whole new meaning to "Pulling Tubes"

[cashandkerouac]

Smokin Joe:  ECC83/12AX7 are very common pre tubes for guitar amps, so just by virtue of the type of tube these are very useful to a lot of people.  ECC83 is the common European reference; 12AX7 is the common USA reference.  both numbers essentially mean the exact same thing.  the fact that they are Telefunken kicks 'em up to a whole other level.  in short, they are highly sought after and worth some good coin.  how many of these do you have?  any other tube types?  pre-amp tubes or do you also have rectifiers and power tubes? 

[Teen Age Riot]

I have a small stash of NOS tubes and I think that these might be worth something. However, even if they test good, the discolored bases (which indicate they've been used) will keep the audiophiles from paying a premium.

Musicians don't seem to like Telefunken ECC83s as much as audiophiles do as they have a reputation of sounding sterile in guitar amps, unlike Mullard, RCA, Tesla,...

I'd post on The Gear Page or the Plexi Palace forum.

[Church-Audio]

I just found a box of tubes in some stuff I inherited.  The guy I inherited this stuff from... he was a musician, and audiophile of sorts.  I can imagine him pulling these from old amps or something and saving them.

How do I tell if these are the ones that are highly sought after?  I know there are "smooth plate" ones and "ribbed plate ones"...  I did a google search, and looked at some pictures, but I can't tell what I'm supposed to be looking for.  I do see some latitudinal bumps in the plates... I guess those are the ribs?

Another think I guess I'm supposed to look for is "Diamond bottom".  I guess this is it, huh?

If they are valuable, what is a good way to get them tested, and maybe even match so I could sell them in pairs?  I'm assuming the machine at Radio Shack (do they even have them any more?) ain't gonna cut it.

They are not worth much unless they are tested. If they tested good. I would say about $15 to $30 MAX per tube. If they tested weak $4.00 per tube.

[runonce]

I just found a box of tubes in some stuff I inherited.  The guy I inherited this stuff from... he was a musician, and audiophile of sorts.  I can imagine him pulling these from old amps or something and saving them.

How do I tell if these are the ones that are highly sought after?  I know there are "smooth plate" ones and "ribbed plate ones"...  I did a google search, and looked at some pictures, but I can't tell what I'm supposed to be looking for.  I do see some latitudinal bumps in the plates... I guess those are the ribs?

Another think I guess I'm supposed to look for is "Diamond bottom".  I guess this is it, huh?

If they are valuable, what is a good way to get them tested, and maybe even match so I could sell them in pairs?  I'm assuming the machine at Radio Shack (do they even have them any more?) ain't gonna cut it.

They are not worth much unless they are tested. If they tested good. I would say about $15 to $30 MAX per tube. If they tested weak $4.00 per tube.

And even then - audiophiles want pairs and quartets...

[Church-Audio]

I just found a box of tubes in some stuff I inherited.  The guy I inherited this stuff from... he was a musician, and audiophile of sorts.  I can imagine him pulling these from old amps or something and saving them.

How do I tell if these are the ones that are highly sought after?  I know there are "smooth plate" ones and "ribbed plate ones"...  I did a google search, and looked at some pictures, but I can't tell what I'm supposed to be looking for.  I do see some latitudinal bumps in the plates... I guess those are the ribs?

Another think I guess I'm supposed to look for is "Diamond bottom".  I guess this is it, huh?

If they are valuable, what is a good way to get them tested, and maybe even match so I could sell them in pairs?  I'm assuming the machine at Radio Shack (do they even have them any more?) ain't gonna cut it.

They are not worth much unless they are tested. If they tested good. I would say about $15 to $30 MAX per tube. If they tested weak $4.00 per tube.

And even then - audiophiles want pairs and quartets...

Not for preamp tubes.. but if you are running a stereo amp and these are your phase inverters or first stage tubes. Then yeah a matched pair. But for preamp tubes generally speaking its not an issue. For power tubes its very important.

[SmokinJoe]

When I first found these, for about an hour I thought "sell them for big bucks on ebay".    But, more likely I'll give them to musicians I know in exchange for karma points.

I'm still stuck with the issue of getting them tested.  I'm not really sure what to test for?  Meaning, I don't want a pass/fail test, there should be some qualitative value to measure.  If they were capsules I'd try to sort them by sensitivity.  I guess the similar property is transconductance?

[cashandkerouac]

I just found a box of tubes in some stuff I inherited.  The guy I inherited this stuff from... he was a musician, and audiophile of sorts.  I can imagine him pulling these from old amps or something and saving them.

How do I tell if these are the ones that are highly sought after?  I know there are "smooth plate" ones and "ribbed plate ones"...  I did a google search, and looked at some pictures, but I can't tell what I'm supposed to be looking for.  I do see some latitudinal bumps in the plates... I guess those are the ribs?

Another think I guess I'm supposed to look for is "Diamond bottom".  I guess this is it, huh?

If they are valuable, what is a good way to get them tested, and maybe even match so I could sell them in pairs?  I'm assuming the machine at Radio Shack (do they even have them any more?) ain't gonna cut it.

They are not worth much unless they are tested. If they tested good. I would say about $15 to $30 MAX per tube. If they tested weak $4.00 per tube.

$15-$30 per tube (if they test good) is pretty good money for pre-amp tubes.  RCA, Amperex, Brimar and Telefunken can fetch between $80 and $100 per tube in the extreme retail market... but that's on the ultra high end of things.  as for musicians not having a preference for Telefunken, i disagree.  most musicians covet RCA blackplate tubes, but there isn't anything wrong with Telefunken. 

JOE:  you can send me some of those tubes and i'll test 'em out in some of my amps.