• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

solderless amplifier?

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"I only trust information I read on the Internet, especially if it's from someone trustworthy, like Abraham Lincoln or Clement Attlee."

"Trust me" (you know who)
At least we have CIA recordings of everything he says.
 

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"How'd yawl build your first project as a kid? bet you didn't use solder."

I remember the 1st Xmas gift electronics set I got. It had all the components on yellow plastic strips with plug-board pegs on the bottom. The terminals at each end were single octal tube pins sticking up, with push-on-clip wires for connecting things up.

Now there are spring binding posts..., etc:
 

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...I remember the 1st Xmas gift electronics set I got. It had all the components on yellow plastic strips with plug-board pegs on the bottom. The terminals at each end were single octal tube pins sticking up...
Man! What you described was MY 1st Xmas gift electronics set!! Looong ago.
And you know what? I know it still lies hiden somewhere in the depths of some cupboard in the house.
 
I sure wish I still had that electronics set around, good memories.
But I think the parts got snipped (ripped) off for use in various projects along the way. It was way more sophisticated than the electronics learning kits I see around nowadays. I might appreciate it better now.

Put up a picture of the electronics set and all the parts if you find it. Historical.

I've been looking through some Google pics of old tube related gear, and I just found
Pomona "surface mount tube sockets"!

Not quite what one might expect these days.

http://www.technicalaudio.com/pdf/Electronics_Catalog_Extracts/Pomona_socket_savers_1960_REM_24.pdf

..
 

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Of course not, they just chose whatever method was most convenient. Still, it shows that screw contacts were apparently not that unreliable under domestic conditions.
I was actually referring back to the earlier part of the thread about whether using solder really makes an amplifier sound different. Anyway, those early radios tended to be pretty simple affairs, with few joints to go wrong.

The solder is not intended to be a conductor, it's a mechanical thing - if done right. Best practise!

Edit: and it's not glue so you better mount/wire the things to be connected in a way that they can take some force - it should work without solder and withistand some mechanical offence... then solder.
I again both agree and disagree. True, solder isn't glue, and a joint (not the cannabis kind) must be mechanically robust before soldering. But the molten solder should improve the electrical conductivity of the joint, by melding with the surface of the copper conductors, and also helping prevent air and moisture getting into the joint which would impair conductivity over the long term.
How'd yawl build your first project as a kid? bet you didn't use solder. Mine was a crystal set built on a piece of wood using brass wood screws and cup washers
Yes, I also built some Crystal sets, and even added audio amplifier stages, with various screw or spring connectors. Then I built a battery valve Short wave radio, and did some DXing, which was huge fun. But I couldn't wait to be allowed by my parents to do real soldering. I never realized at the time, that the audio quality would suffer :)

Sent from my phone with Tapatalk. Please excuse any typpos.
 

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> reading somewhere recently by a very well respected audio bod

US Navy, basic e-tech training course--- yes, respected audio bod.

He works in the Swedish army also, I see.

I heard it from NASA training.

Every organization solder training touches on this.

> first have mechanical integrity then be soldered, the solder's primary function being to preserve the mechanical connection.

Lead is mechanically terrible. It "creeps" with pressure/tension, and never stops creeping. Old leaded-glass windows, and old lead pipes, sag.

Therefore we first make a mechanical wrap that will NOT move.

Unless it is an engineered Wire-Wrap connection, we can not trust it to be or stay electrically good. Tarnish never sleeps. Terminal wraps are not gas-tight (WireWraps are). Therefore we clean the tarnish and solder the joint for a lasting electrical contact.

This is debatable (but not with your navy/army instructor!). Early high-reliability PCBs had leads bent or crimped so the parts WERE solid-support before solder. Most later PCBs omit this. Many SMT parts are only held-on by solder. Turns out that tin-lead has a low-low threshold below which it does not creep. May be 1% of the breaking strength measured with a few-seconds pull. However parts are small, and their mass is getting smaller faster than their leg-areas shrink. Obviously we don't have cellfones with loose SMTs inside. (Also we keep cellfones a year, not centuries like church windows or some pipes.)
______________

> solder is not intended to be a conductor, it's a mechanical thing

No, the solder IS the reliable conductor. But NOT a reliable mechanical joint.
 
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