I wasn’t surprised that the Stadium amp had very little circuitry when I opened her up, she sounds very direct and uncomplicated.
A real point to point beauty laid out intelligently and very little of the ‘rat’s nest’ jumble to deal with.
This little thing has a few wiring surprises such as the inputs going directly to the volume control before hitting any tubes or resistors. More on that later as I plan to open up and analyze the circuitry of each amp that has been presented here to date.
There are no markings at all on the speaker of the 400-T. It’s an odd choice of speaker given the size of the cabinet and I have to admit to never having seen an oval shaped one in a guitar amp before. It looks like something intended for a car stereo setup but I can’t argue with the results of the sound.
The tube setup is a bit unusual as well. The 35W4 rectifier is coupled with the 50C5 output for what looks like a the classic old radio trio but instead of the usual preamp companion of a 12AV6, we have a 12AX7! The 12AX7 provides more bite here than is generally found in amps that feature the radio tune lineup.
A fried hard drive has canceled part two of the look at the circuitry of the Estey T-12, so we move right along.
This is a 1958 Stadium 400-T, a rare bird that is difficult to dig up documentation for, either online or in books. As can be seen from the slightly warped rear panel that adjoins the control plate, the wood on the amp is plenty thin.
I’ve never seen nobs like these and they are either plastic or perhaps bakelite. The handle and its mounting look to be straight off a piece of late 1950’s luggage.
The brushed steel panel is somewhat like that of a vintage Fender but the lesser grade of metal doesn’t have quite the same shine. There are three inputs but it’s the middle port that provides the highest gain.
Tiny little tube amp made by Estey Electronics of Torrance, CA in 1967. Sweet clean tones are plentiful from the T-12 and here’s brief snippet of what chords sound like.
While I wait to get the Orpheum to a location where I can turn it up louder, here’s a clip of the Silvertone 1470, all the way up.
A real spaghetti junction!
Point to point wiring.
Just not all that orderly.
When I pulled off the back of the Orpheum, I expected to find a Jensen speaker, as I’ve read they originally featured.
But, as can be seen above, it was not to be!
Researching the numbers, it appears that the speaker was made by The Best Company sometime in 1971, which makes it definitely a replacement speaker.
Regardless of who made the speaker, it sounds great! It isn’t as smooth or as clean as a Jensen but in this case, that’s fine since I want a ratty blues grit coming out of the amp and the Best speaker delivers.
I made another unexpected discovery when learning that one of the speaker wires is coming off the large electrolytic capacitator rather than both coming from the output transformer. This can be seen in the photo above as the leftmost cable of the pair of white wires heading off to the speaker.
Dusty Old Amp 
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