Wooden Eyelet board on "boutique" amp??!

[wizard333]

I had to open up a fairly well known boutique builder's amp recently due to what turned out to be a bad solder joint to a channel-switching relay board.

What to my wondrous eyes did appear but a WOOD eyelet board. Not any kind of neato wood either, more like the thin balsa sheets you can pick up at any hardware store. I could put my finger right through it if I was so inclined.

The amp works fine and sounds good, but a few things leaped to my mind:

1) Wood doesn't like moisture. It retains it, and can swell, rot, all kinds of neat stuff. Not exactly what I want in something seeing multiple points of HT.

2) Mechanical reliability: as mentioned, I could my index finger right through it or easily crack it. Cleary couldn't do that with a plexi or fiberglass board.

3) Fire hazard. If a screen grid, etc., goes tits up, this whole amp can literally catch on fire and burn to a cinder.

This is not a cheap amp.

Am I being silly here, or does this strike you guys the same way?

[DrGonz78]

I want to see some pictures if possible. We could start building similar amps using an "Old Smokey" chassis.

[tedmich]

Interesting use of wood! Even the Dumble wood grain boards were just printed Formica right?

[Justin Thomas]

I don't know! I can't tell from all that blue bird poop inside!

Justin

[52 Bill]

I can't believe that it could be Balsa. I doubt that you can press eyelets into Balsa without it splitting.

[Chuck H]

I use wood all the time! I make the speaker cabinets out of the stuff. Can you believe?

I can't imagine how anyone who would choose to make a circuit board from wood has the savvy to create circuits and amps that anyone would want.

[Mick Bailey]

At least tell us what make/model it is. My guess is it's a Two-Rock, but put me out of my misery.

[rjb]

I can't believe that it could be Balsa.

I bet he meant lauan plywood.

[g1]

I'm surprised a modern manufacturer would be doing this, but I have seen it before in older stuff.
Keep in mind that lots of high voltage electric utility poles are wood, albeit with insulators.
This is what the boards were made of in an early 60's amp from around here. It was not a one off, it may even have been a Celestion kit.

[The Dude]

I'm surprised a modern manufacturer is allowed to do this and that it could pass any kind of certification.

[octal]

That's a Johnson Sound Systems amp "Celestion Model" which was a combo sold with (wait for it) Celestion speakers. I have a very similar looking Johnson Monarch. The board seems to be some sort of formica type compound, it looks a little like wood but there's no wood in there!

This was in regards to Post #8, I just bungled quoting G1 properly.

[g1]

And the transformers are also Celestion brand. I think this is why some speculate it may have been some kind of kit sold by Celestion.

[teemuk]

Well, I guess it's about using "authentic" materials to accomplish something that was relevant, say, almost a century ago.

When we "breadboard" a design the roots are in literally sticking nails to a breadboard and building a proto circuit. Nowadays we ofcourse have better tools for that.
...Just like we have better materials than wood or formica to build circuit or eyelet boards, or whatever.

The amp designers / builders who lived that century ago probably would have preferred our modern technology and materials too. But they didn't have a choice back then.

But as said, it tries to remain authentic to something that was relevant ages ago. Not now.

But what did you expect from "boutique".

Boutique = small shop.

I don't see how that term in any way actually could give clues about product's quality. Truth is, small shops can manufacture poor quality products too.

[Chuck H]

Well sure boutique has a definition. But it also has a cultural perception that is commonly applied. When I tell someone "Here's mud in your eye!" I don't actually toss mud in their eye (Ok, I do. But that's not the point).

And if we REALLY want to be authentic we should be forgoing chassis grounds for two prong AC connectors!?! Maybe the guy could see to it that all his amps are delivered exclusively by horse and buggy too.

I remember that "bread board" was an actual bread board once. I thought it was a clever way for early developers to make a lot of headway before this stuff was commonplace with readily available prototyping materials. And I've never considered building an amp on one because it would be stupid.

[J M Fahey]

FWIW I *still* (46 or more years later) use breadboards made out of chipboard (no, I don't let them get wet) , nails and brass wire.

I HATE Protoboards, for many reeasons :
1) when I started in late 60's they weren't even invented yet. (Now Teemu will post some obscure patent from the Southwestern Duchy of Khrakhizschya where a certain Muhammad Ling Popofieff invented it and was used to design the VOX AC 4 prototype or something )

2) in my learning literature (yellowing "Radio" magazines from the 40's on) they were an *established* method for experimenting

3) they were quick and *cheap.

4) most important, you could *solder* parts, they wouldn't move (lots of shorts possible in Protos because of parts long legs) , you could screw heavy large parts to them, including transformers, L shaped front and back panels, tube sockets floating a couple centyimeters on the boards, with legs bent out loke stars (or octopuses) , what's not to like?

5) they could be transported, more than one amplifier started as a copper spiderweb on a coffee/bar table or chair, on stage, being played (and tweaked) live.

6) I *still* use them, at this moment one holds a FET version of a full Soldano preamp, other holds a 12V 40/60W battery powered amp (with output transformer and servo driven IRF MosFets for linearity) , a Photometer, an add-on short pritection, a thermal Fan speed controller, etc.

Besides, anything involving TO220 / 218 / 247 legs or 1N540x or 6A2 or any kind of bridges (beyond W005) or fuse holders or a ton of 'Power" stuff can't be plugged in a Proto anyway (I know some people does, but I pamper mine) so my 20's technology breadboards are still alive and useful.