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Discussion Starter #1
A question for the experts,

I have this old reel to reel that was in my parents house forever that I've been keeping for parts, it hasn't been turned on since the '70's,

I was on the look out recently for tubes-sockets/ac switch/pilot light/transformers and whatever else I can find for a build, I remembered I had this so I dug it out to have a look.

It's a Masco Sound Reel Model 52 eight inch recorder/player with a 500 ohm (??) speaker out line, in a lacquered tweed box, it looks 1950's to me, with a nice leather handle still in good shape.





I was really surprised at the condition, the Hammertone finish is excellent and except for the corrosion of a few screws (that were fastened into part of the frame that's aluminum), the thing is near mint.

So I did a smoke test and it was all good, then I decided to fire it up...

Zero hum, zero noise, not really even a scratchy pot, so I wound up a tape and wow, it works quite well,

I think the cover has really helped to preserve this thing, here's the amp that resides under the gear drive transmission that is the tape mechanism.



Tubes are 6V6GT 6SN7GT 12AX7 6X5GT 6SL7GT

Below is why I think it works perfectly - it's the most minty mint on the inside - blow this picture up and have a look please.

My question is does anyone think any of the caps resistors etc are worth using in a project?

I came for the tube sockets/ac switch/pilot light and the like (which are in excellent shape), but I'm wondering about the rest of it because it all looks so good, please let me know what you think gents.

PS there's a bunch of stuff in there that isn't part of the amp circuit, it's there to feed the tape head.

 

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Is there any sort of collector's market for equipment like this? I think, because it is so original and minty, it would be a shame to rob it of parts. But if it has no value, to you or on the market, I guess you do what you can to recycle at least some of it.

I suspect it has a 500 ohm speaker because 600 ohms was the standard, pre-SS, for interfacing audio equipment. It possibly has a 600 ohm output to connect to a console or bigger amp or something?

Back then, everything was transformer coupled and, like tube amps, impedances had to be matched so that you only lost 3 dB per inter-connection. With solid state drivers, output impedances fell to ohms, if not 10ths of ohms, and now everyone just makes sure the input impedance is much higher than the output impedance (easy to achieve) and there is no loss in the interconnect.
 
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Agree with keeping it stock if it has some value. Then you could sell it and buy an easier project.
I wouldn't count on those caps (or resistors) for use elsewhere, for the little you save, it's not really worth the risk.
 

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There is not much there usable for any amp build in my opinion. Every wax cap an e-cap in there is well past its best before date. Not worth cutting it up.
Masco however made some tube PA systems that are awesome for guitar amp use. I picked up a 1946 Masco PA a few months ago. Everyone who reads this thread needs to keep
an eye out for old Masco PA equipment and buy it. Here is what my Masco amp sounds like. Yes it's that little head that looks like something from WWII.
With and without a dirt pedal:


Below here is natural break up, before I serviced the amp. It had original wax caps in it. I have since
completed a full service and am very happy how it turned out.
 

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Well, first, I wouldn't use these old caps and resistors.
Transformers, tubes, sockets, switches, pots are very usable for champ alike amp.
Even speaker could be ok.
Math is simple, if you can get more than $300, sell it, (which I doubt), otherwise use the parts for your build, you can make nice small amp out of it.
Cheers, Damir
 

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Well, first, I wouldn't use these old caps and resistors.
Transformers, tubes, sockets, switches, pots are very usable for champ alike amp.
Even speaker could be ok.
Math is simple, if you can get more than $300, sell it, (which I doubt), otherwise use the parts for your build, you can make nice small amp out of it.
Cheers, Damir
Speaker may be OK, but at 500 ohms, it would look suspiciously like an open circuit / high impedance load to most tube amp output transformers. Unless of course you could put about twenty of those speakers in parallel. Now that would be interesting!

I also have an old Masco MA35 that I bought for a retirement project (it's already mod'd for guitar but could use some more work). Very old school tweedy sound. And good to know I have a resource here to ask some questions, if/when the times comes. Hell, I could even drive it up to Kamloops with a case of beer or two, if things go really bad!
 
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Discussion Starter #7
This thing is probably worth $200 to the right person but it must weigh 50 lbs and I’m not into shipping or finding a buyer so I’ll probably grab what I came for.

Looks like Masco did some good work using good parts, I'll bet the amps are sweet.

Thanks to all for chiming in.
 

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would be neat to build that into a little gtr amp that has on-board echoplex!
 
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Remember this: The electrolytics have to be replaced. They're probably on the verge if not already failing. Same goes for the wax caps. They are susceptible to absorbing moisture from humidity and those are ancient. I wouldn't at all be surprised if the're are leaking DC. Same goes with the resistors. The resistances are most likely all over the map.
 

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I wish I could find units like that...fender champ in a box! Nice bunch of tubes and iron, just rebuild the circuit into whatever you like with new resistors, caps, a fuse and 3 prong cord and you will have a real cool amp!
 

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I'd suggest researching sources for schematics if re-sale is not an option. Then you can isolate the tape section off and maybe re-utilize the pre and output sections for guitar with minor mods to the preamp. De-soldering tube sockets is not fun, requires a ton of patience and personally, I'd get new sockets elsewhere if you're moving to a new chassis.
Certainly a cap job should be in your future as you shouldn't expect longevity or accuracy for these. Nice tube complement here. looks like a cool piece.
 
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