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