audio tube list

[jdwk]

is there a list of all the tubes most commonly used in amplifiers? meaning a list of tubes people want that aren't for weird old outdated tabletop radio's and such?

I know some of the tubes, but if I happen upon a big bunch of tubes, and a 12ax7, or a KT88 doesn't immediately jump out at me, whats a good list of things to look for that say "this lot hasn't been completely picked over yet" . Sometimes I hope to eventually find "useful" tubes that I don't need to trade towards ones I want to try. I'd like to be able to spot and weed out stuff that has almost no value (demand) so I don't waste money.

 

[BmWr75]

The Brent Jessee web site has a pretty extensive of HiFi related tubes.

https://www.audiotubes.com/audtube.htm

 

[TriodeLuvr]

Yes, please don't buy up the remaining NOS tubes for that weird old stuff. I need them for the weird old stuff I build.

 

[jdwk]

Yes, please don't buy up the remaining NOS tubes for that weird old stuff. I need them for the weird old stuff I build.

I got offered a box lot of telefunken tubes that were "battery valve tubes" need those? most of them began with a D , some were DAF. I meant the stuff that no one uses anymore, the lots i've seen so far were cheery picked and had tubes that had no value.

 

[TriodeLuvr]

Well, there are really only a few types that have no value and little or no use for audio. Things like thyratrons and dual diodes come to mind (although the latter might be useful to someone building a compressor). The tube listings at Antique Electronic Supply are pretty complete for what you want, and each type has a short explanation of its function.

Antique Electronic Supply - Vacuum Tubes

Jack

 

[init4fun]

Yes, please don't buy up the remaining NOS tubes for that weird old stuff. I need them for the weird old stuff I build.

Great post Jack!

Us weird old guys who collect weird old radios don't need any more competition driving the prices up.....

(Oh look, is that a pair of weird ol coke bottle 6L6 outputs in there and maybe a 6J5 or two, , , naa, couldn't be)

Well, there are really only a few types that have no value and little or no use for audio. Things like thyratrons and dual diodes come to mind (although the latter might be useful to someone building a compressor). The tube listings at Antique Electronic Supply are pretty complete for what you want, and each type has a short explanation of its function.

Antique Electronic Supply - Vacuum Tubes

Jack

But seriously, one useless for audio tube that immediately comes to this old TV repair hobbyist's mind is the "High voltage Rectifier", such as the 1B3/1G3 types

 

[BluesWalk]

All of the common "new old stock" tubes that people have been scrambling for, for years have been successively picked over again and again over the decades leaving what is currently available today which is a far cry from what people want to think was available back in the heyday. Some designers today are engineering they're tube audio around tubes that have been generally overlooked by the mainstream because of their abundant supply and the virtues that audiophiles seek in new old stock. One that comes to mind is Leben.

Otherwise, there is new production which some of the best known and most reliable hi fi audio brands design their components around like Luxman and McIntosh, VTL and they rely on the common brands manufactured in Slovakia, Russia and China. You know it may not be long when these brands are held in as high esteem as the classic ones such as Mullard, Telefunken, Phillips, Raytheon etc.. I've used Sovtek, Svetlana and Shuguang for decades and more recently JJs and have no complaints.

 

[isaacc7@cox.]

is there a list of all the tubes most commonly used in amplifiers? meaning a list of tubes people want that aren't for weird old outdated tabletop radio's and such?

I know some of the tubes, but if I happen upon a big bunch of tubes, and a 12ax7, or a KT88 doesn't immediately jump out at me, whats a good list of things to look for that say "this lot hasn't been completely picked over yet" . Sometimes I hope to eventually find "useful" tubes that I don't need to trade towards ones I want to try. I'd like to be able to spot and weed out stuff that has almost no value (demand) so I don't waste money.

The easiest to find overlooked useful tubes are the same as the usual but with a heater voltage other than 6.3v. This is especially true for octal preamp/driver tubes. 12sn7, 8sn7, 25sn7, 12j5, 12j7 and more. It is an easy way to pick up otherwise crazy expensive tubes. This is ideal if your building it yourself but often times it’s not so difficult to add different heater voltages to an existing amp with the use of adapters.

There aren’t as many output tubes available with the same trick. 12v6, 12aq5, 8aq5, even 18aq5. Beware the *l6 tubes! The 6l6 and 12l6 have nothing in common!

Another great thing to look for is equivalent tubes with different bases. If you like Sylvania tubes the 7n7 and 7c5 are the same as the 6sn7 and 6v6 respectively. Loctals beginning with 7 are 6.3v and ones beginning with 14 are 12.6v. The 6ar6 is the same-ish as a 6l6gb with a different base. The 6/12/16gk6 is the same as an el84/6dq5 with a different base. The 5b/25* series are 807 equivalents with loctal bases and different heater voltages. If you want to get even crazier you can look at combo tubes like double diode/triode and just use the sections that are useful to you. This type of tube was the end state of vacuum tube manufacturing technology with compactrons.

The only way I know of getting this knowledge is by dredging through forums like this one, Audio Asylum, DIYaudio, and more and more head-Fi. Often times lunatics on those forums are ahead of tube dealers as far as what tubes are worth buying.

There are tons and tons of useless tubes out there. Detector tubes, remote cutoff, variable mu, oscillator, ballast tubes, the list goes on and on. Most of the tubes you see in the old repairman tube caddies are useless for amplifiers. Over the years they tend to get consolidated into useless bulk collections.

 

[Mr Boochie]

https://mkratz.pt/
Caution: extra slow site. Let each page load before doing multiple clicks.

My favorite reference is Ludwell Sibley's Tube Lore II.

 

[Lavane]

I've noticed sweep tubes and transmitter tubes being used more. The prices for some of these thbes have gone up too. My headphone amp uses a RF signal tube for the voltage gain stage to drive two 12AX7's.

 

[PakProtector]

I just keep thinking, 'my definition of an audio tube is different from most other folks'. Taking the mainstream, it is still a long list. Taking it to what I would wish to experiment with, it quickly gets longer. Up to and including stuff like the GU-81m or similar insanity like an 833. Sweep tubes are often a very fine for power tubes. The other-than-6.3V-heater voltage usually make these far less expensive. Some of the sweeps have been hunted to unobtainium prices on stuff like 6JE6C, 6JS6C, 6LF6 to name a few.

Same goes for power supply tubes. The GZ34 is a very fine twin diode. They are low drop and tolerate a fair PIV level. To get substitutes involves what the main stream calls 'TV tubes'...but delivers a significant cost reduction on top of a performance capacity increase.

Douglas

 

[init4fun]

In one of my bulk tube purchases years ago I ended up with a bunch of these(like at least 50 NOS), basically a 6J5 with the grid and plate brought out through the top. I could see me someday building an amp using an army of these driving some sweep tubes like the ones PakProtector mentioned, of which I also have boxes full of NOS.

 

[TriodeLuvr]

In one of my bulk tube purchases years ago I ended up with a bunch of these(like at least 50 NOS), basically a 6J5 with the grid and plate brought out through the top. I could see me someday building an amp using an army of these driving some sweep tubes like the ones PakProtector mentioned, of which I also have boxes full of NOS.

I have a good stash of RK-34 tubes and the appropriate NOS sockets. These are dual 5W triodes with a common cathode. I've been saving them for use eventually in a headphone amplifier. The goal is to set them up with a negative supply and output transformer under the cathodes, and to ground the anodes. This will eliminate HV above the chassis, as well as the need to install insulators. It might be fun to drive each channel with a 7193.

Jack

 

[Lavane]

The 6LR8 sweep tube amp I built can also use 3 or 4 other sweep tubes to produce 1.2wpc to 5.5wpc. There is an earlier version of the 6LR8 that has an anode cap on top. I almost went with them instead. They were a whole dollar cheaper at the time. I bought 4 6LR8's for $5 each back then.
I bought a few of the other sweep tubes to try, but in the end I went with the 6LR8's.

 

[Lavane]

I have a good stash of RK-34 tubes and the appropriate NOS sockets. These are dual 5W triodes with a common cathode. I've been saving them for use eventually in a headphone amplifier. The goal is to set them up with a negative supply and output transformer under the cathodes, and to ground the anodes. This will eliminate HV above the chassis, as well as the need to install insulators. It might be fun to drive each channel with a 7193.

Jack

View attachment 3325946

The dual caps reminded me of those power transformers with dual rectifier sockets on top. It would be cool to find one of those. Or even one with a single rectifier socket.

 

[ceylon]

The easiest to find overlooked useful tubes are the same as the usual but with a heater voltage other than 6.3v. This is especially true for octal preamp/driver tubes. 12sn7, 8sn7, 25sn7, 12j5, 12j7 and more.

asking prices for 12SN7, 7N7 and 14N7 have gone thru the roof. some are asking sky high prices for 12SL7 as well. dont know if any are selling at obscene prices the asking has gone koo koo. ugh.

 

[Mr Boochie]

I have a good stash of RK-34 tubes and the appropriate NOS sockets. These are dual 5W triodes with a common cathode. I've been saving them for use eventually in a headphone amplifier. The goal is to set them up with a negative supply and output transformer under the cathodes, and to ground the anodes. This will eliminate HV above the chassis, as well as the need to install insulators. It might be fun to drive each channel with a 7193.

Jack

View attachment 3325946

Wasn't these tubes also known as "rabbit ears?"

 

[TriodeLuvr]

asking prices for 12SN7, 7N7 and 14N7 have gone thru the roof. some are asking sky high prices for 12SL7 as well. dont know if any are selling at obscene prices the asking has gone koo koo. ugh.

I bought quite a few 12 volt tubes before prices shot up, back when a sleeve of identical 12SN7 or12V6 could be had for $20 or $25. A search of eBay completed listings indicates most of these are selling now for $20 to $30 each. That's much less than their 6 volt counterparts, but more than I would spend today if I was still collecting.

Jack

 

[Palustris]

I've got a good supply of NOS GZ34, but never use them in a new build. I save the GZ34 for classic amps that use them. All my power supplies are separate from the amp chassis so I can use whatever I want for a rectifier. I have been using the 6CJ3/6DW4B which has a max current flow of 350mA with a 25V drop. Two are required since they are a damper diodes and they use a MagNoval socket which is a bit of a pain. But the tubes are cheap and I have a good stock of sockets so I have been very happy with them without a single failure so far.

 

[Mr Boochie]

I've got a good supply of NOS GZ34, but never use them in a new build. I save the GZ34 for classic amps that use them. All my power supplies are separate from the amp chassis so I can use whatever I want for a rectifier. I have been using the 6CJ3/6DW4B which has a max current flow of 350mA with a 25V drop. Two are required since they are a damper diodes and they use a MagNoval socket which is a bit of a pain. But the tubes are cheap and I have a good stock of sockets so I have been very happy with them without a single failure so far.

NOS GZ34/5AR4 are worth their weight in gold. As long as you have units that use them, NEVER sell them.

By the way, Philips-ECG (USA) made several batches of 5AR4, "5V4GA" labeled rectifiers for the military. Philips-ECG made the tubes using Sylvania 5AR4 jigs.

Sylvania 5AR4. Philips-ECG "5V4GA." GE 5V4GA.

I've used these Philips-ECG rectifiers in several of my amps and in fixes for others. They test like strong 5AR4. The red arrow points to the 525-volt-rated cap can that I used to replace the OEM 475-volt-rated one.

There was this seller who would occasionally put these tubes up on eBay. He bought a pallet of them from a military surplus site. They were quite the deal for those in the know. I haven't seen his eBay postings in several years, but I keep looking.