SM56 cartridge replacement and repair.

**Steenamaroo** · 11-10-2012

Hey all.
Henry sent me over an old SM56 for repair.
On arrival it worked, but it didn't sound just right.
Next day it sounded different.

So I took it apart to investigate.

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The little black wires that go from the main body to the cartridge assembly were a little worse for wear.
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So I replaced those.
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Here they are cut to fit.
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Now....The reason the mic's sound changed.
The diaphragm glue had dried up and the diaphragm was completely loose.
Anything more than a light tap made the whole diaphragm and coil move slightly.
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Unfortunately the coil wires had become weak too, and one of them actually broke at this stage.
You can see them here, disappearing into little holes under the diaphragm.
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So, now my mission was to find a cheap replacement cartridge for an sm56.
Is it the same as a 57 or 58? Tune in next week to find out.

**Steenamaroo** · 11-10-2012

Here are two pics comparing the dismantled cartridge assemblies for the sm56 and my sm58.
It doesn't look like it in the pictures, but apart from the plastic 'cap' on the 58 cartridge, they are the same size and shape.

I didn't want to remove the cap from my own working 58 just incase I damaged it,
but my hunch was that removing it would reveal a plain ol' 56/57 cartridge.

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**Steenamaroo** · 11-10-2012

So, hi-ho, hi-ho, it's off to ebay I go.

And what do we get on ebay?????
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You guessed it......
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Fake stuff

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No matter.
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Refund given, and back to ebay to look for old mics.

**Steenamaroo** · 11-10-2012

And what did I find?
An old Shure PE58d (I think?!)
I went out on a limb and bought it for about £30, and here's what I found.
But does that plastic cap come off????
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Yup. It sure does.

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So now all I have to do is fit Henrys sm56 parts on to this cartridge.
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Made for each other......Kinda.
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**moresound** · 11-10-2012

Great to see this in the DIY forum, Paul.

People would kill for that microphone in the snare recording position.

**Steenamaroo** · 11-10-2012

A thread about tweeters and AKG d12s got me thinking.

Couldn't I remove the coil from Henry's original diaphragm, tease new lengths of wire out, then glue it back in place?

And it turns out, yes....
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I could do that.

I left the 56 alone with the PE cartridge assembly. It sounds tip top and I'm chuffed to bits with it.

I fitted the repaired diaphragm back into it's own cartridge though, and put that in the pe58 body.
It does sound a little dulll I guess I musta been heavy with the glue or something?
Maybe I'll take it apart again and do a cleaner job this time, now that I know I can do it.

I'll post up a final pic and clip of Henry's mic soon.
I also bored out the base and cemented in a standard thread mic stand ring from a little plastic clip.
The original threads were either an uncommon type, or damaged.

Now it mounts right on to any of my stands.