The it's crap tubes/design, maybe? I have an amp that makes a good 10W with 6F3P tubes collecting dust under my bed (Belcor Fax-200)
https://www.canuckaudiomart.com/details/649332138-belcorroland-6bm8-tube-receiver-made-in-japan/Apparently, they went up in price!
https://www.tubes-store.com/product_info.php?products_id=83Still far less than 6BM8 though.
The 2N2147 PNP germanium TO-3 part was the go-to transistor for HiFi in the early 60's. Unfortunately, to a kid with a limited understanding of electronics, they were remarkably easy to kill as was the "universal replacement" the HEP230 and whatever the RCA SK series part was. The big TO-36 transistors off the back of a car radio (2N174) were much harder to kill as long as you kept them below about 20 volts. In the early 60's my power supply was a rectified and filtered Lionel train transformer. It went from zero to about 20 volts at several amps. The 2N3055 came into vogue when I was in high school. At that time, fakes were not common. What WAS common were factory rejects that made their way out the back door and into plastic bags at Poly-Paks, Radio Shack, Olson, Lafayette and others. Some blew up, some didn't.
I was wandering through a local surplus shop in the late 60's when I spotted a tray full of RCA house numbered TO-3 transistors (39414 with a 1967 date code). I asked what they were, and the reply was "2N3055." Of course, every surplus TO-3 NPN was a 2N3055 back then. I bought a couple and subjected them to some testing, and cut one open, then went back and bought them all for about 60 cents each. I still have some in a box somewhere. While still in high school (1969), I built a monster "booster" amp with 6 of them cooled with a blower running on a B+ of about 100 volts. It used the transformer driven totem-pole circuit commonly seen with 2N2147's. The amp was used for guitar and PA duty and driven with a tube type guitar amp. The amp never died, but eventually wound up in a storage shed that got demolished by a hurricane in 2006. I let the waterlogged amp dry out and plugged it in. It blew the line fuse, so I jumped the fuse and tried again. This caused one of the electrolytics to spew, so I stripped out the heat sinks with transistors, and tossed the rest. The transistors are still good. Remember that this was built by a 16 year old kid with a hand drill and a nibbling tool.
A few years after high school I found a big heat sink with a muffin fan on each end and 24 X Westinghouse 2N3773's on it in a scrap yard. That assembly made the mother of all booster amps that cannot be discussed here due to its rectified wall outlet power supply. There was the driver transformer isolating the input. Its output power was unknown, but it was "a lot." I saw it melt a cable connecting up a speaker cabinet when the other end got shorted. That amp lived on as the PA for a Florida rock band well into the 80's when I lost track of it.
I had built one channel of the Lil Tiger in high school. It was the output section in the first complete transistor guitar amp I ever made. The wimpy Radio Shack power transformer and small 6 inch speaker allowed it to survive everything I threw at it. A few years later I started my career at Motorola, where they gave us free transistors for filling out a sample request form. Myself and our self proclaimed " Motorola audio club" made clones of every Tiger amp in existence except the Tigersaurus. We didn't build it because we couldn't find a suitable power transformer. We, the "Motorola Computer Club," also cloned the SWTPC 6800 computer, but that's a different story.
I never built anything with 6BM8's, but a pair of 50C5's in push pull can crank out 20 watts forever using UNSET technology in push pull. This is an unfinished little guitar amp breadboard. The Triad N-68X is the power transformer. The OPT is partly visible among the tube boxes (follow the blue wire). I let it run at 20 watts for an overnight meltdown test. The next morning the power reading on the 8903A read 20.03 instead of 20.00. THD at 20 watts (edge of clipping) is under 3%. It remains under 1% below 5 watts without any feedback.
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I still have some Jimpak 6800 and 6502!
An uncle worked for a distributor which had Motorola, Sylvania and RCA transistors in their lineup, so I had some nice samples....but being into ham radio in the early 1960's I was more into hacking TV's and making sweep tube transmitters. The transformers in TV's were perfect for this application.
I actually liked writing code back then, when writing code was 6800 and 6502 assembler. Won’t touch code with a 10 foot pole today, even though it’s supposed to be “easier”.
In the early 1980's there was a Tandy store here in Haarlem where you could buy a bag with transistors that were supposed to be 2N3055's for some small amount. I doubt if they really were, because most of them were in TO-220 packages rather than TO-3. I used them for everything when I was about 11 or 12 because they were not so easy to blow up as small transistors (like the BC238). Of course the hFE and fT were rather low, especially at low currents, but I didn't quite understand subtleties like that yet.
Great minds think alike to some degree at least - I found some 2N5631’s once from some place like Poly Paks, and put 6 of them to use off a rectified 120 volt line. It was a conventional amp topology with a QC output triple, horizontal outputs as drivers, video output as the VAS, with an output capacitor and transformer driving the 2N5087 input stage. I paid through the nose for the single 2N3439/2N5415 pair I still lacked. The pair was like $15 from a TV repair shop but you have to have them. There is no substitute for a low leakage complementary pair as the first stage of a triple! When I found 40-0-40 8 amp power transformers for $15 each from some other place like Poly Paks I scooped up the 4 I could afford and some 30,000 uF 75 V caps from a ham fest. Built two, bridged them, ditched the output caps and input transformers, and didn’t have to worry about getting shocked anymore. MCM came along a couple years later and I bought D424/B554’s and converted them into real amps. Oscillation problems I was still having magically went away my 2nd year of school, after I took the controls course. BARELY got my “A” by the smallest margin in history, but I learned a lot in that course.
Those BM8’s are starved for heater power. Same heater power as the EL84, but it also has to supply the triode so you can’t get as much current out of the pentode. Relatively high quality, but single digit watts from a pair. Those 50C5’s run hotter ‘n hell - to get as much power density out of 110 volts DC as it can muster. And they don’t sound too bad doing it. Doesn’t surprise me you can coax twenty watts out of two of them.
Clinging to a device such as cellphones is really not a normal way for a human to live.
Think about the days before cellphones - people, society, got along quite happily.
While those things can provide some worthy services, they become overused, abused, and dependent on to a point of causing both self harm and harm to others.
Television, on the other hand, isn't a "mobile" device in the traditional sense, excluding perhaps "apps" that provide that service.
They've done recent studies on people that have been "addicted" to their mobile phones, and the results are not surprising. (re: "Nomophobia")
Like any other addiction, being without the use of them, or even using a mobile device with low battery charge, shows that people become nervous, agitated, and depressed.
Worrying, depending on a place to plug that phone in - is that a normal way to live?
No different than a drug or alcohol addiction, which we all know is a problem.
It's just not healthy, being dependent on some things.
Dependency can take the form of other things as well... gambling, sports, even eating,.. obsession with trivialities in life....
In order to get through life in a healthy and beneficial way, limiting certain things, keeping a healthy "balance" is wiser in the long run.
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My RS used to sell a pack of 6, usually one house-numbered TO-3 and the rest TIP3055.
They also had packs of 6 triacs for $1.99 - which got built into disco light shows using PAR38 colored floods and lots and lots of C9 Christmas lights.
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