Any info on this mystery amp?

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Hello! I recently bought this very old and very cool Guild amp off ebay and havemt been able to match it to any available documentation. I emailed Guild and they said their old records, especially of amp models and schematics, was very limited. I am hoping that someone here might be able to help me identify this in order to aid my restoration efforts.
Ill provide the poor quality pictures i currently have of it but will gladly take more if need be. Here is a description. It is a 1x15 combo (original speaker missing, unfortunately) completely (once) covered in tweed. It is a 2 channel model with tremolo, volume and tone controls for each channel, and a jack labeled "solo jack." The amp itself is split into two chassis with the preamp up top (labeled using 3 6SN7s and one 6SL7) and the power amp mounted on the bottom. (Tube sockets are unlabeled or screen printing has worn off) The power transformer has no discernable markings but the output transformer is an Acrosound ultra-linear TO-251.
Any insight or help would be greatly appreciated! I doubt i will find a schematic but if i can at least know what power tubes and phase inverter it uses i feel confident that i can get it working...eventually.
Thank you in advance for any help!!
 

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I have a few Guild amps from the Fifties and I have seen something similar in the past ten years, but I don't know a model number. I haven't ever seen it in any of the catalogs, but I also have three that share that distinction.
 

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If you can give me some closer shots of the chassis and control panel, I can have a better understanding of what is going on. Two of the undocumented amps I have use split chassis and an umbilical, but they are a 2X6L6 configuration. It appears to be the size of a Masteramp 110, which has 2x5y3 rectifiers, 4x6V6gts, a 6SN7 for the trem oscillator, and 4x12ax7s. I haven't seen a Guild amp with octal preamps that early. The 100 MFD, 5 volt caps are bypass caps for the preamp tubes. I have them on a 1957 Masteramp, but not on any of the later models. It's too late for me to really concentrate, but I would appreciate some non angled shots of the chassis' and control plates.

Right now, I'm leaning toward a 5AR4 rectifier, a quad of 6V6GTs (possibly 6L6s, depends on the B+ voltage). I'll look at it with fresh eyes tomorrow.
 

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Welcome to LTG! Any date codes on the potentiometers that can narrow the age?

Ralf
 

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I'm betting on 1955-56, based on construction and more photos. It's cathode biased, but I could use some shots of the area in shadow just to be sure.
 
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Thank you all so much! Here are some better photos. I kind of figured the power tubes were probably 6v6s just based on the age of the amp.
It looks to me like it uses one rectifier. But has a total of 7 octal bases on the power amp chassis. 4 of those are obviously the power tubes, so the 2 on the far left must be sometheing else. One must be the phase inverter. Is the other just an additional gain stage? Or is there a 2-tube phase inverter arrangement?
 

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The two sockets on the left. Not sure what the far left one is doing, at the moment. The second from the left is definitely part of the phase inverter, you can see the black .1 mfd caps going to the power tubes.

Look up by the pilot light. See the red wire cracking? On one of my amps of this vintage, several of those wires cracked until it looked like a Christmas tree string of popcorn. Make a careful inspection of the wire throughout the amp and confirm that that is the only spot, ok? Give me a bit to go through the pictures and draw out a diagram.
 

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Here is the front control panel after a light cleaning.

Yeah a lot of the wires in the umbilical cable are cracking or have holes in the insulation! I figured i might have to replace the whole umbilical.
 

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I darned near had to do that. There were probably two or three different kinds of wire used in my amp, and the one type had to be completely removed. I think that your amp was an attempt to make the 110 more manufacturer and repair friendly. The 110s have the tube sockets jammed so closely together that I get a headache just looking at them.
 

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The pinout on the second from the left tube socket matches the 6SN7, so I'm confident that is what the phase inverter tube is. I'll work on the other tube socket. It might be part of the trem circuit or a gain stage tied into the trem circuit. Normally in this vintage, there is a 10 henry choke in the tremolo, but I don't see one here.
 

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This one is better than my 110s. Stacked circuit boards, extension pop riveted to the chassis, dual rectifiers, four output tube sockets jammed into the space for two.

Schnikes.
 

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