Crawls Backward (When Alarmed)

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1958 Rickenbacker M-8 Amplifier

Suddenly it's late-1950s small amps time here in the Dungeon!

This one is a 1958 Rickenbacker M-8.   These seem to be the most common Rickenbacker amp out there - I've seen these more than their larger amps.

I've always been curious about these and was fortunate to snag one along with a matching lap steel.

This is a small amp - the speaker is an 8 inch Jensen, so you can judge how tall (or short...) the amp is.

I like the silver-blue covering.  It's a fabric of some type; it's not Tolex.

The handle is either cute or cheesy, depending on how you look at it.  The amp is so light that the handle works fine.  I'd bet Rickenbacker got these really cheap.   There are some other obvious budget components to be found elsewhere, too.

The control panel is on the back.  Like many of these small amps, it's a very basic layout.  One combined AC switch/volume control, two inputs, a fuse, and a pilot light.

The pilot light jewel is green!  Nice touch.

This one says it's an M-8, although the circuit corresponds to the later M-8E model, with the ubiquitous 12AX7, 6V6, 5Y3 tubes.

You can see how clean this amp is - it's seen very little use I think.

Basic circuit and budget components galore.

This is real point-to-point wiring.  Aside from one lone terminal strip for the speaker output, everything is wired with flying components and leads.  It's pretty tidy, but it does have a "science project" look to it.  There's no spaghetti insulation used on any of the leads.  Looking at it is a bit scary.

Note the use of ceramic capacitors throughout.  Definitely a cost-cutting measure.  I'm going to put some better quality caps in for sure.

The output transformer is labelled Philco.  It sure looks original.  I don't see any signs of it being a replacement.  I'd be interested to know if Ric used these in all M-8s.  If you have one, contact me.

Closer look at some wiring...yikes.

Not exactly mil-spec wiring.  Or even good practice.

I suppose it's charming in a way.  If you know what I mean.

At least they didn't cut corners with the quality of the tubes and speaker.  As I mentioned earlier, the speaker is a Jensen.

The rectifier (5Y3) and output tube (6V6) are both Sylvanias with 1959 date codes, I'm pretty sure they're originals.

And check this out.  The 12AX7 (preamp) is one of the very famous Amperex "Bugle Boy" tubes!  The labelling on the tube is in perfect shape.  It's probably worth more than the whole amp.

Handle this thing gently.  Don't want to rub off that silkscreening.

I won't be putting this back in the amp.  Well, maybe just for a test.

I'm going to restuff the filter cap can and fiddle with the circuit a bit and see what this little amp will do.





 
 
 
 

Post a Comment 2 comments:

  • Jeff said...
    July 24, 2015 at 2:18 AM
    How'd this project turn out?
  • Yr Fthfl Blggr said...
    July 28, 2015 at 4:35 PM
    It came out well. You can see the results here:
    http://crawlsbackward.blogspot.com/2013/11/rickenbacker-m-8-amp-rebuild-complete.html

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