Know anything about old Gibson Amps?

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octagon
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Know anything about old Gibson Amps?

Post by octagon »

My friend got an amp that looks like this in his store today I think he said it was a 1948. It was recently overhauled by Savage Audio so it has all new tubes and caps and the speaker is not the original,it is a 12" Jensen from the 50s or 60s. It has an inputs for instruments and mike. I think that Savage Audio may have made some changes to it because my friend has used it for several years as his main amp for gigs.

Think it is worth $350? That is what he wants to sell it for.

If you plug a guitar into the mike jack and dime the volume it sounds like The Black Keys.

The cabinet looks like this pre-war EH-125(maybe darker)

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and the amp inside looks like kinda like this pre-war EH- 150(but the speaker is a 12" Jensen)

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scott_s
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Re: Know anything about old Gibson Amps?

Post by scott_s »

Heh, I just posted something on that Tele board. 8)

- Scott
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octagon
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Re: Know anything about old Gibson Amps?

Post by octagon »

scott_s wrote:Heh, I just posted something on that Tele board. 8)

- Scott
Thanks Scott, The amp does looks like one of the Pre-war amps but I think he told me it was made in 1948.Maybe I misunderstood what he said.I have to ask him tomorrow.
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soundmasterg
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Re: Know anything about old Gibson Amps?

Post by soundmasterg »

Many of the old Gibsons like that sound pretty cool, and often have a pentode input instead of a triode input on the amp, so they are often excellent harp amps. they are also often underpowered, use some odd tubes, and have extremely poor layouts inside the chassis as far as working on them. I HATE working on vintage gibson amps. :) Some of them are pretty cool though...definitly a lot for harp, and quite a few for guitar too..

Greg
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octagon
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Re: Know anything about old Gibson Amps?

Post by octagon »

soundmasterg wrote:Many of the old Gibsons like that sound pretty cool, and often have a pentode input instead of a triode input on the amp, so they are often excellent harp amps. they are also often underpowered, use some odd tubes, and have extremely poor layouts inside the chassis as far as working on them. I HATE working on vintage gibson amps. :) Some of them are pretty cool though...definitly a lot for harp, and quite a few for guitar too..

Greg
Thanks Greg! I called my friend today and he told me that the amp was made sometime between '41 and '42. He said the speaker was replaced in '51.

I found a schematic for this amp:

http://www.ampwares.com/schematics/gibson/eh-150.pdf

Here is a article about these amps from Vintage Guitar Magazine

My friends amp is Style 4:


"STYLE 4 (Ca.1941-'42)
The final variation showed up in Catalog BB, dated 1942, with a rearranged control panel, having the tone switch replaced by a potentiometer, ranging from Treble at 0 to Bass at 9, with Normal halfway between. The picture was the once-again retouched version of the '37 catalog's shot. A major change in the circuit (that may have occurred earlier) was the tube phase inverter, with a twin-triode 6N7 replacing the transformer. Also new were the 5U4 rectifier and the three 6SQ7 high-mu triodes (amplification factor of 100), with two for the microphone channel and the third common to both channels.

An interesting placement of tubes on the amp, which was not included in the retouched catalog shot, features the power tubes on either side of the rectifier tube, not standard anywhere else in the world of amps, but somewhat logical. Removal of the tubes to satisfy our curiosity revealed marked sockets from the factory, so this apparently wasn't the result of repairman monkey business. Sadly, the Echo Speaker output was removed for the final 150, possibly to save money on the center-tapped output transformer previously used. By this time, the EH-150 and the previously supercharged EH-185 shared the same circuit design, right down to the schematic."
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octagon
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Re: Know anything about old Gibson Amps?

Post by octagon »

I made a mistake,it is an EH-125

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