Looking at a vintage Shure 55 microphone

after pulling this guy out of my storage
and experimenting with it a couple of weeks ago comparing it to my my new
cheap microphone I figured I’d revisit this guy and come dig a little bit
deeper into it just just for the fun of it it’s a neat piece of history so this
one as I said I picked it up at a at a secondhand store who had got it from a
church that bought it back in well when it was new presumably back in the
forties or fifties or whenever that was it sounds pretty weak and I’m I’m
guessing some of that is just degradation due to age and some of it
the fact that it’s got a really well output right now it’s probably due to
the iron magnet in it losing its magnetic properties over time as happens
so this is the sure can we even see this this is the sure model 55 with no
apparent suffix supercardioid yoona dine unidirectional dynamic microphone made
by sure brothers of Chicago Illinois over here there is a tag identifying the
impedance and I’m having trouble reading it but this particular model has an
impedance adjustment switch here which we’ll take a look at the spec the
official specs in a minute but that allows us to change the impedance that
this microphone presents out the connector to the amplifier or recording
cone or whatever from a low of I think it’s 50 ohms to a medium which is in the
150 to 250 range to a high which is in the I want to say 10k range but we’ll
look at that on the official you know information in a minute so this one the
basic microphone doesn’t have an on/off switch the on/off switch is an ad
a little module here which has the sure brothers logo on it as well I cleaned
this one up a fair bit when I first got it it’s still not perfect but it’s got
some vintage look to it let’s go and take a look at some of the information
that I found online about this guy so as far as I can tell from the part number
model number that’s on it and the clues that I’m finding this is probably the
1947 model where the model was introduced in 1947 because that’s when
they added the impedance switch the nameplate just says 55 I can’t see a
five five six though it may be because it does say on the tag supercardioid and
the next major change that they made was 1951 where they changed the size of it
to the small size and the added and XL connector which this one doesn’t have so
that pretty much dates it to somewhere between 1947 and 1951 or possibly a
little bit later but that would be the manufacturer dates anyway I have no way
of knowing when the church that originally bought this thing picked it
up but I’m gonna guess that somewhere in that range so this is the data sheet for
the 1951 model over the S the slightly smaller one there are there were other
versions SW with switch the gold version which had a gold-plated finish which
would look pretty gaudy and I don’t know that I’ve seen any pictures of them
although I’m sure they’re out there somewhere as they’re saying they’re
ideal for high quality public address theater sound systems roll broadcasting
applications and other sound applications such as hotels stadiums and
public auditoriums though I note in the in this official sure document that has
the history of it they’re talking in a pre nineteen forty seven they’re talking
about voice clarity and paging and two-way radio systems they’re not even
talking about broadcast or well maybe his public address
or live stage or any of that kind of stuff so some of the reasons for the
different impedances so 150 to 250 ohms is what a typical microphone microphone
these days comes in around it’s kind of become the standard the low impedance is
generally intended for a long cable length so you don’t get as much induced
hum into the into the cable and the high impedance versions were for use directly
into a tube-based amplifier which typically do have a high impedance input
just that’s the nature of the beast however a lot of amplifiers and whatnot
also have a transformer as the first input stage for matching so tube
amplifiers that were designed with a for medium impedance 150 to 250 ohms would
generally have a matching transformer and as the front stage also a lot of
earlier condenser microphone preamplifiers
to get the phantom power on they would use a center tap on that transformer
that way they could send the power out to the microphone through the center tap
and get it evenly the same positive voltage on both pins two and three and
then ground would be on pin 1 and that would isolate the phantom voltage from
the grid voltage the grid bias voltage on the first tube input stage of course
nowadays since no almost nobody is using tube preamplifiers that’s not really
done them so here we’ve got the general specs some replacement parts and whatnot
and again this is the switched model the W which I don’t have on mine but it
shows some some ways to get into it to do some
repairs and maintenance and down here we have the typical frequency response
chart and the cardioid pattern so this is looking from above see most of the
sound will come in from the front there’s a little blip at the back but
that is 10 DB lower than the peak at the front that’s fairly wide compared to
some microphones and here’s the frequency response on a logarithmic
graph you notice it’s relatively flat from was that probably about 125 or so
up to 1,100 Hertz and then it bounces off about 4 DB higher than that until so
it’s 1600 and then it craters right down to 10,000 compare that to its modern
cousin the ubiquitous a shure sm58 and it’s a Lillian response is actually very
similar it stays flat pretty much the same but the drop off happened the high
frequency drop off happens a lot higher stuff at that little bobble in there
though so if mine was in good condition it would it wouldn’t sound yeah it
wouldn’t have the high ends as much as a 58 would but it would sound reasonably
close so and again this is looking at a slightly more modern version the 1950’s
version but there is the how the impedance switching is done let me just
grab that Zoomer tool here again so basically it’s done with a transformer
there is the actual microphone cartridge no there’s the microphone cartridge over
there there’s a matching transformer and then the little switch just selects
what’s going on when I first got this one I said I bought it used they didn’t
come with a cable or connect or anything and I didn’t have available to me the
correct fnl connector I had I did have a four pin one so this
is the shell off that and then I just butchered up an xor connector to poke
into the holes I’ll just pull this guy out pin one of the ground and pins two
and three so that’s that’s the original connector that it should have for this
age from the 1908 40s early 50s thing and this little module here is just a
switch so I should be able to I know I can I haven’t been inside this thing for
probably twenty something years since I bought it but so there’s across the
original wiring in there yeah that hasn’t been moved in a long time gonna
have to be careful but there is the optional add-on switch it’s just a
rotary on/off switch I want to be a little bit careful that I don’t mess up
that screw but it’s not in there very tight anyway I think I just probably
taken it with the coin it looks like it’s designed for that exact purpose so
there is how this guy actually originally came or would have come
without the optional switch so no there’s four screws to get inside the
head and I’m going to be careful because I don’t want to damage anything and I’m
not you know I’m gonna get a better screwdriver than that there that’s a
better fit as I said I don’t care about the resale value on this thing because
I’m never gonna sell it but I don’t want to mess up something that’s this cool
and old so as for screws hold the grill on just
drop them out and it’s not being I think it’s just being held in there by
friction and aid okay there we go so there’s the grill off and the cloth is
in pretty good shape a little bit of Goodes and staining and stuff in here
but I think a lot of that is actually just the glue that holds it in so a
little tiny tear in the cloth down there that’s been there for a long time I’m
gonna leave that mostly alone that mate well I just dusted out a little bit but
that’s about it so here is the internals this foam back
here is your shock mounting foam and that that is something that I replaced
about 20 years ago what was originally in there was a similar density but it
was really beat-up and just dry and crumbly kind of like those that rubber
there that rubber just sort of holds this whole assembly back off the face a
little bit in case it gets whacked so there is the impedance matching
transformer which we saw a little bit about only on the website there on that
manual there’s the two wires coming out of the voice coil so this whole assembly
oh hello and look at that take in a second so
that whole assembly it’s held in by these two screws on the
back simply bringing them out Oh what was that covering and a half oh look
back at the video and just see but anyway there we have the whole mic
capsule assembly that’s just the bracket that holds it the whole thing is sprung
for shock mounting I’m not going to go in any further because it’s got this
grill cloth glued on there but down in there we can see the transients matching
transformer and the switch and up in there I’ll try and get a good view of
that the original patent a 1946 so it’s not much that I can do to this old fella
to improve the sound of it other than selecting the select and the correct the
impedance for the preamplifier that I’m using
I’ll just gently put this guy back together alright now that I’ve better
reassemble though let’s see if it still works hello one two three
yes it seems like it does so this is set to the a medium impedance setting well
thanks for watching a pre sheet you’re coming along for this little ride I hope
you found this interesting I certainly did I was like messing around with his
old stuff anyway um you got anything to to ask or say about this please leave it
down in the comments as usual I’ll talk to you later

15 Replies to “Looking at a vintage Shure 55 microphone”

  1. You had me worried there, I thought you were going to butcher it. Haha

    I've got a few similar style mics around but I don't think mine have the switch. They had line impedance shifting transformers you could plug between cords too. The last new line transformer I bought was in the 80's. A P.A. system I purchased in the 80's had on board phantom power but it also had 1/4" phono jacks for instruments or older style microphones. At one time they made adapters for all those different mic connectors. Probably have to hit a vintage shop to find one today but we know the internet has everything these days.

    I've got a few old Turner brand models that don't work and I think I may stick some modern guts into them to bring them up to speed yet retain the classic Buddy Holly and Elvis look.

  2. Those were beautiful mics. I'm in a kind of unique location because I live a few miles from the original home of several different companies from the music and sound industry. Electrovoice in Buchanan, Michigan, Conn Organ, Crown Audio in Elkhart, Indiana and several more. Many famous musicians and actors were from that area Like Tommy James and Perry Como.

  3. Very nice! … The blues brothers! … I lived in Schaumburg for 6 years (just outside Chicago) these mics look amazing… I m glad you had wired it up so we could hear it!! I have a few SM58s and some R0DE NT-1s … I wonder how many words have been said into this mic?

  4. Have fond memories of this microphone. Not limited to any city, state, country or famous person (except pileofstuff). Thanks for showing

  5. Beautiful vintage piece of kit. They really knew how to make stuff to last back then and the looks are so classic. Thanks for sharing.

  6. I just picked up my second "fat boy" 55 today (55C, high-impedance only) and although it sounds marginally louder than my multi-impedance 55 they are both quiet, tinny, and resonant. Yours sounds hi-fidelity compared to them. I suspect you're right in that the magnets in the capsules (and maybe the transformers) have likely lost strength over the years, leading to reduced frequency response and output. I wonder if there's a way to re-energize them without destroying the capsule?

  7. Shure still hosts the 1951 version of the user guide for this mic on a page on their web site called "Discontinued Microphones User Guides." They have a bunch of period catalogs too to see what else was being made at the time. Nice job on the video. The two 55s I've purchased were both damaged beyond restoration (one was a completely empty shell), so it's great to see what the inside is supposed to look like!

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