OT - Tubes

[aron]

I saw this rather alarming video about the state of tubes. I haven't been following but is it really true that there is basically only Svetlana tubes left?
Also, that they are back ordered for months?
Should we buy whatever is left now or is this over-reacting?

[antonis]

I don't often deal with tubes but the times I did there was no problem with Sylvania (Baldwin) supply..

[davent]

I saw this rather alarming video about the state of tubes. I haven't been following but is it really true that there is basically only Svetlana tubes left?
Also, that they are back ordered for months?
Should we buy whatever is left now or is this over-reacting?

thetubestore which is local, has stopped taking orders and closed their website , totally swamped.

http://temporarymaintenance.thetubestore.com/?whence=

[antonis]

https://www.skroutz.gr/c/780/music-organ-amplifier-accessories/m/6090_22691_56554/JJ-Electronics_or_Electro-Harmonix_or_TAD.html

[GGBB]

thetubestore which is local, has stopped taking orders and closed their website , totally swamped.

http://temporarymaintenance.thetubestore.com/?whence=

Interesting. I was there the other day and noticed that their prices were about double what they were a few months back, which in turn was already up a fair bit from pre-pandemic prices.

I don't get it honestly. I understand the Ukraine-Russia thing would disrupt Russian supplies for a bunch of popular brands like EHX, and Mullard, Tung Sol, Svetlana (which are all EHX brands I think, made in the same factory), but there are tons of tubes made in China, and JJs are made in the Czech Republic I think. So I think hoard mentality has led to opportunism. Crazy times and crazy people.

[imJonWain]

^ exactly what he said.  People panic buying and/or trying to exploit the situation for resale.  New Sensor does supply tubes for a lot of brands but not all and panic buying is bogging down the distributor supply of JJ & Chinese tubes.

[davent]

^ exactly what he said.  People panic buying and/or trying to exploit the situation for resale.  New Sensor does supply tubes for a lot of brands but not all and panic buying is bogging down the distributor supply of JJ & Chinese tubes.

2022's toilet paper and hand sanitizer

[FiveseveN]

Can we just let tubes have a dignified end of life? 116 years was a good run.

[Kevin Mitchell]

I got the news on Monday. One of my folks/clients were worried about future procurement of tubes for their stuff and was asking me to modify their multi-channel tube amps to save a few spare preamp tubes. While I think it's a bit of an overreaction I did shoot some ideas their way. They went ahead and ordered spares of what they may need for future maintenance.

If that was just one guy's reaction over a few amps I'm going to guess that the market will dry up very fast.

[GibsonGM]

$15/US for a 12AX7...glad I put a few aside! 

[Wavelength]

Guys,

It's like anything... toilet paper during initial covid... Everyone after the EHX email went out and bought enough tubes for their lifetime. But really if you are going through tubes like crazy then your amp isn't designed right.

On a minimum touring amps for big bands every 3 years and that's only because they are moving the stuff around like crazy.

Most of my amps last for a minimum of 10K hours of use with a set of tubes. I have had users use my amps for decades before changing tubes.

So really if you start the crazyness then your part of the problem.

Thanks,
Gordon

[Wavelength]

All,
From Mike Matthews EXH just now.

Attention All EHX Tube Customers

The export restriction on Russian tubes has been resolved for now. We are accepting new orders, processing backorders, and hoping to resume shipping in April. Priority will be given to the oldest orders.

Considering various economic pressures, we must raise our wholesale prices. This price increase, to be announced separately, will apply to all back- and new orders. Also, there will likely be a further price increase once the U.S. implements heightened tariffs against Russian goods.

You can cancel any backorder, but we do not recommend this; there is a tremendous shortage of tubes.

Mike Matthews

[Kevin Mitchell]

Thanks for the update, Gordon!
I had relayed this info to my guy as I'm pretty sure the scare announcement originated from EH - per the conversation I had.

[Fancy Lime]

Can we just let tubes have a dignified end of life? 116 years was a good run.

NEVER!

Seriously, have you met humans? It's a bloody miracle that so many have by now adaped to buying food at the store instead of going hunting with wooden clubs.

But yeah, I too find our reliance on tubes a little nuts.

EDIT: Come to think of it, in a week or two, after the nuclear apocalypse, we'll probably be back to knocking game over the head with sticks. I hear the youngens are all itching to go clubbing after those past two years anyway...

[GibsonGM]

They ARE pretty EMP-resistant...

[mozz]

What about all those germanium transistors from over there? I think they usually ship from The Russian Federation, or Ukraine. Prices used to be very good for 100 pcs.

[amptramp]

Designers seem to keep using the same tubes over and over again.  I have built amps with horizontal sweep tubes for the output and a pair of 6BQ6GT's will give you 25 watts with cathode bias and 30 watts with fixed bias and a pair of 6DQ6B's will give you 35 watts.  They may not be cork-sniffer high fidelity tubes but who needs that in a guitar amp?  It is easy to get better gain from a 6AU6 pentode than from a 12AX7 triode and if you only need one section of a 12AX7, the 6AV6 has the identical triode in it (along with two diodes).  NOS sweep tubes are still plentiful and cheap and the 6AU6 supply does not seem to be in any trouble.

The only difference designing with sweep tubes is the low allowable screen voltage which is usually regulated to 150 volts from screen to cathode.  If you have a pair of 6BQ6's, use a 4000 ohm plate-to-plate impedance transformer and run the plates from a 300 volt source.  You can cathode-bias the stage from 270 ohms / 2 watts.  If you want to increase the output to 30 watts, use a grid bias of -30 volts and no cathode bias.  A pair of 6BQ6's will idle at 50 mA and go up to 70 mA with program drive and 165 mA with a single tone in Class AB.  I got this information from the 1956 Radio Amateur's Handbook.  They like sweep tubes as modulators for AM since they are cheap and powerful.

Transmitting tubes should not be overlooked either and the supply seems to be unaffected by recent events.  The only transmitting tube used in any amplifier I have seen is the 6146 and a pair of these is good for 75 watts.  Six of them in push-pull parallel were used in the Ampeg SVT amplifier although these got changed later to 6550's but both versions were rated at 225 watts.  And of course, there is nothing like having a plate cap on a tube to say 'we mean business about power'.  The 6146 is normally operated at 500 volts on the plate using a 4200 ohm plate-to-plate transformer to get 75 watts, but you can hot-rod it to get 95 watts at 600 volts with a 5200 ohm plate-to-plate transformer or 120 watts at 750 volts with a 6700 ohm plate-to-plate transformer.  As with sweep tubes, you need tight screen regulation on a 6146.  The output transformer will be more difficult to find than the tubes.

It wouldn't make much sense for a major manufacturer to bring out a new line of tube amps but we are DIY'ers.  I can use tubes from A-1 Electronics in Toronto or tubes I get at the London Vintage Radio Club in London ON Canada.

[printer2]

For 6V tubes used in conventional amps the easiest is to use 6V tubes but anyone wanting to build an amp themselves there are 12V options of common tubes such as 12AQ5's, 12V6's, 12AB5's.

[GGBB]

$15/US for a 12AX7...glad I put a few aside!

At thetubestore it was double that when I checked a few days ago.

[GibsonGM]

maybe this will make the less-known but good tubes come to the forefront...