This is why I try to limit myself to current manufacture. The situation would only get worse - as I build for myself.
Unfortunately tubes that made the most power, transconductance, or whatever, for the least money are no longer made. Current production is all about tubes with the widest, and deepest market penetration.
Since I generally design and build something that I want for myself, but tend to share the designs, I need to choose tubes that are still plentiful. I also buy a lifetime supply of tubes that I actually use. My expected "lifetime" isn't getting any longer, so that supply requirement may only be a dozen tubes or so.
Unfortunately today's semiconductor situation is heading down the same path.
Since I generally design and build something that I want for myself, but tend to share the designs, I need to choose tubes that are still plentiful. I also buy a lifetime supply of tubes that I actually use. My expected "lifetime" isn't getting any longer, so that supply requirement may only be a dozen tubes or so.
Unfortunately today's semiconductor situation is heading down the same path.
I tend to use RS Components as a valve source.
They 12AU7, 12AX7, EL84 and EL34.
They usually have China written on them.
They 12AU7, 12AX7, EL84 and EL34.
They usually have China written on them.
I haven't bought any of those random tube assortments, but the ones I could see the tube types in clearly, usually are full of "junk". The good stuff has been sorted out.
Maybe less than 1% of all tubes are of interest for audio anyway, would just be filling up precious storage space to buy randomly.
On the other hand, if you forgo the usual audio cliche' tubes, there are TV types with good properties that can be had from certain vendors for $3 to $6 still. ESRC is sorely missed now though. Unfortunately, naming them online can get the prices orbited or the supply decimated. Like 6HB6, 6GB5...
I think the most promising development lately is the UnSet/CED, "new" series Schade schemes, which can turn mediocre tubes into winners. There are plenty of tubes around, like big LV triode regulator tubes for example, with mediocre plate curves, waiting to be turned into audio "gold". Still plenty of unappreciated tubes, like 38HE7 (half of a 42KN6), or 9DX base tubes, and some video tubes like the TFH for $3. The "gold" is not lying on the surface glittering in plain view anymore, you need to do some searching and research to find hidden gems.
Maybe less than 1% of all tubes are of interest for audio anyway, would just be filling up precious storage space to buy randomly.
On the other hand, if you forgo the usual audio cliche' tubes, there are TV types with good properties that can be had from certain vendors for $3 to $6 still. ESRC is sorely missed now though. Unfortunately, naming them online can get the prices orbited or the supply decimated. Like 6HB6, 6GB5...
I think the most promising development lately is the UnSet/CED, "new" series Schade schemes, which can turn mediocre tubes into winners. There are plenty of tubes around, like big LV triode regulator tubes for example, with mediocre plate curves, waiting to be turned into audio "gold". Still plenty of unappreciated tubes, like 38HE7 (half of a 42KN6), or 9DX base tubes, and some video tubes like the TFH for $3. The "gold" is not lying on the surface glittering in plain view anymore, you need to do some searching and research to find hidden gems.
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Heres a bargain on a EC8020, you could build the left channel then wait a few years for the next EC8020 to go up on ebay to build the right channel, only $2500. Get it while its hot!
Genuine Telefunken <> EC8020 / EC 8020 Audio Amplifier Power Triode Tube, NOS | eBay
Genuine Telefunken <> EC8020 / EC 8020 Audio Amplifier Power Triode Tube, NOS | eBay
Having spoken to the real "expert" in Russia only last week, I can assure you that bad mouthing Russian fabs is based only on ignorance.
It was an eye-opener.
What you can't know is how much machinery went for scrap over the last decades, simply because there was no space to store an obsolete production line (for people who have no idea about mass production methods and quality control standards).
Who was badmouthing Russian fabs? Frankly their SIT transistors are as good as any from Japan (if lower power), I just can't see why you'd keep making valves at all.
The same storage problem arose when CDs started to take over. Australia's record presses ended up being dismantled for lack of a place to store them. One enterprising band (Hunters and Collectors) bought several and started their own pressing plant, but they were incompetent.
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In many places of this world a large lot of tubes is not viewed as being worth the price of long term storage, or the land that they are stored on. The 100,000 lot of tubes that I mentioned in post #15 was already being scooped up in bulk with a front end loader and hauled off as scrap when someone saw mercury and called hazmat. The land that the warehouse was on was about to become a residential housing development, and all that old junk had to go....now! This was in the 1990's. Land in Florida, and many other places has skyrocketed in price far faster than the perceived value of a bunch of obsolete old electronic junk.
Fortunately my friend saw some sellable aircraft parts in the rubble and bought the entire contents. There were hundreds of valuable tubes that had already been crushed, and the vandals had already smashed most of the big tubes for fun. There were hundreds of broken 833A's, 211'a, 845's and 807's.
Stan (ESRC) passed away a while back. His warehouse on the outskirts of Orlando houses 4 million tubes. He had other warehouses scattered around the country. What will happen to those tubes?
Thinking back to the 1980s and '90s when I used to buy boxes of tubes from local guys and pick tubes out of trashed TV sets, I can't believe how many perfectly good tubes I didn't take because they weren't "audio" types. I mean, I had a box full of 6K6GT and all sorts of stuff I can't remember that I literally threw in the dumpster after I couldn't sell them. I never thought I'd use stuff like that.
Now that you all have so graciously taught us all about sweep tubes, RF pentodes and UHF triodes, all that good stuff... now it all gets scarce and expensive. I'm always late to the party...
Oh jeez... I just remembered that I used to shop at Leeds Radio's warehouse in Brooklyn back around 1993 or so. Bernie G had piles upon piles of boxed up tubes in there. If I had known to look for sweep tubes and RF pentodes, he would have pretty much given them to me. If I knew then what I know now...
Now that you all have so graciously taught us all about sweep tubes, RF pentodes and UHF triodes, all that good stuff... now it all gets scarce and expensive. I'm always late to the party...
Oh jeez... I just remembered that I used to shop at Leeds Radio's warehouse in Brooklyn back around 1993 or so. Bernie G had piles upon piles of boxed up tubes in there. If I had known to look for sweep tubes and RF pentodes, he would have pretty much given them to me. If I knew then what I know now...
It used to be easy to walk through the swap meet area at a hamfest near closing time and get boxes full of tubes for real cheap or free. The big three hamfests (20K people) did not happen this year, and one HamCom in Dallas will not return. It remains to be seen what will happen to the others, and many smaller local shows.
The free or cheap tube thing was still possible as of three years ago, but not as common as it was a few years ago.
Tubes are occasionally found in antique shows or stores. Sometimes the owners have looked up Ebay prices and attempted to get them from a smaller diversified local market without success. I saw a seller with some tubes in her indoor antiques flea market shop for years. There was a good covering of dust on them. I asked how much for all and she explained that she had a shed full out behind her house in rural Florida, her father was a TV repair man. I got one cubic Volvo Station Wagon full of "tubes" for $100.
Once home I went through them all. Many of the "tubes" were Sprague and Aerovox twist lok capacitors still in their original boxes. I put them on Ebay stating that they were stored in non climate controlled conditions outdoors in central Florida for probably 20 years and were likely dried out, but they fetched BIG bucks to bidders in Hong Kong and Japan. That left me with a large supply of tubes that I got paid to take away. Can't beat those kind of deals, but they are much rarer today than about 20 years ago.
I found an old dirty and rusty Sparton radio chassis at the same flea market for $10. The tubes all had stickers on them as was common a long time ago. Some had legible dates on them, all from 1929. The pair of NX-483's are still running fine as the output tubes in my TSE amp. An NX-483 is like a 45 with a 5 volt filament. They are 92 years old!
The free or cheap tube thing was still possible as of three years ago, but not as common as it was a few years ago.
Tubes are occasionally found in antique shows or stores. Sometimes the owners have looked up Ebay prices and attempted to get them from a smaller diversified local market without success. I saw a seller with some tubes in her indoor antiques flea market shop for years. There was a good covering of dust on them. I asked how much for all and she explained that she had a shed full out behind her house in rural Florida, her father was a TV repair man. I got one cubic Volvo Station Wagon full of "tubes" for $100.
Once home I went through them all. Many of the "tubes" were Sprague and Aerovox twist lok capacitors still in their original boxes. I put them on Ebay stating that they were stored in non climate controlled conditions outdoors in central Florida for probably 20 years and were likely dried out, but they fetched BIG bucks to bidders in Hong Kong and Japan. That left me with a large supply of tubes that I got paid to take away. Can't beat those kind of deals, but they are much rarer today than about 20 years ago.
I found an old dirty and rusty Sparton radio chassis at the same flea market for $10. The tubes all had stickers on them as was common a long time ago. Some had legible dates on them, all from 1929. The pair of NX-483's are still running fine as the output tubes in my TSE amp. An NX-483 is like a 45 with a 5 volt filament. They are 92 years old!
If those tubes don't find a new home soon, they may end up under a leaky roof or hurricane. If they go for the highest price possible, they might end up someplace like B____y B___ selling with prescription drug prices. We do need a time machine it would seem.
God, when I think about all those lightglobe-shaped UX-245's I threw out. They fetch $175 these days.
Very late to the party, it seems. Electronics Australia designed a 60 watt guitar amplifier in the sixties using 6DQ6A tubes from TVs. I built one, it kicked @ss!
I'm not an engineer, just a hobbyist who didn't get started with building tube hi-fi stuff until about 1990. Either you're an engineer and knew about this stuff 30 years ago or you're a LOT older than I am!
😛😱😀
😛😱😀
I used to put 6BQ6GT's into a Fender Champ like circuit for simple SE guitar amps and the 6DQ6 A into push pull guitar amps. I used these as they were the most common tube types in the trash dump.
A few years back I was a small hamfest in north west Pennsylvania near closing time when the rain came. A seller had jumped into his car and drove off leaving a bunch of unsold "stuff" behind assuming that someone would take it for free.
A couple of hamfest organizers were complaining about having to drag it to the trash because there were just "worthless TV tubes." I had already packed up and was headed out to my car from the bathroom because it was about a 2 hour ride home. When I heard this I wandered over to look and saw about 50 boxed tubes laying on the ground. I explained that I could make a nice 50 WPC HiFi or really kick A$$ guitar amp from these tubes and have enough smaller tubes left for some low powered amps. One called BS and the other said no way. At this point I took off my T - shirt, tied the two sleeves together and filled the open end with all the tubes and walked away.
Most of that collection is still in this box. Most are new tubes, and I have indeed seen over 100 WPC come from a push pull test amp from the 4 tubes in the lower left corner.
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There are still some very good deals to be had out in Eastern Europe, but they never went in for the latest and greatest in the USA in 12 pin compactrons (sadly).
I just cleaned out a world supply of high performance mil spec GEC stuff which came in at 2 EURO each in an obscure place, and much of what France produced is largely forgotten.
Unlike the Citroen 2CV....you'll be lucky to find even a half decent one for under 15K!
The same fever is gripping all ,markets, a pure sign of an impending crash, - unending speculation.
People go mad in crowds, and come slowly to their sense individually and after a lot of therapy and time.
I just cleaned out a world supply of high performance mil spec GEC stuff which came in at 2 EURO each in an obscure place, and much of what France produced is largely forgotten.
Unlike the Citroen 2CV....you'll be lucky to find even a half decent one for under 15K!
The same fever is gripping all ,markets, a pure sign of an impending crash, - unending speculation.
People go mad in crowds, and come slowly to their sense individually and after a lot of therapy and time.
17DQ6B?? That's a new one on me. Looks to be just a 6DQ6B with a higher heater voltage?