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Scott Dorsey Scott Dorsey is offline
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Default Shure Mic Mixer Transformers

Paul Babiak wrote:
On 08/31/2018 08:31 AM, mcp6453 wrote:
Has anyone here evaluated the mic transformers in Shure M67/M267 mixers?
These mixers are going for low prices on eBay, so I wonder if the
transformers are worth $5 each salvage. Are they 1:1?


Lot's of info about these out there. Transformers are 1:14

Have a look at this:

https://messageboard.tapeop.com/view...&highlight=m67


There are two kinds of transformers in there.

The input transformers are indeed high ratio, and they are awful like most
high ratio transformers are. Top end quality is poor, distortion is high,
which is a consequence of trying to put so many turns on the secondary like
that. Shure did this because the high ratio means you can skip a gain
stage and these were just intended for voice applications anyway so who cares?

The output transformer, though, is a low ratio (probably 1:1) transformer
with a funny tertiary winding intended for a mike level output. It's
hard to screw up a dry 1:1 transformer, so I would not be surprised if that
one turned out to be actually useful.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."