21 N. Shafer St.
Athens, OH, 45701 Sheet #i-5903 Updated 7/15
800-848-2273 Fax: 740-593-7922
Firebird Mini Humbucker Pickup Kit
Assembly Instructions
The mini humbucker first appeared on Gibson® Firebird Alnico 2
guitars in the early 1960s. Outwardly, it looks similar to a Bobbins bar magnets
(#5453) (#5458)
Les Paul® Deluxe mini humbucker, but without adjustable
polepieces. Inside, the two pickup designs are very different.
The Firebird mini humbucker design has dual bar magnets
with steel plates above and below them, a higher output
and a brighter sound. Steel
plates
Winding technique (#5454)
Gibson wound their pickups on machines, and the mechani-
cally precise traverse of the wire across the coil resulted in
very consistent layers of windings. You can experiment with
winding very methodically like Gibson’s original winding,
Baseplate
or allow more inconsistency as you hand-feed the coil wire (#5450)
(called “scatter-winding”).
Overwound, underwound Maple shims
(#5455)
The number of winds affects the pickup’s tone and response.
For example, adding 5% more winds than usual will produce
a higher output with more midrange punch; a warmer sound
with less top end.
On the other hand, winding a coil 5% under spec results in
a more open sound, with greater high-end clarity but less
28 AWG lead wires
output. (#5949)
Gibson Firebird coils were wound with 5,000 to 5,500 turns Vintage braided
push-back hookup wire
of wire, averaging a DC resistance of at least 7K. (#5950)
Some manufacturers offer pickups with different outputs for
neck and bridge pickups, usually making the bridge pickup Preparation
sightly more powerful to blend better with the neck pickup. Carefully inspect the bobbins to make sure there are no
Another way to affect a pickup’s tone and response is to rough edges, nicks, or molding lines that may snag the coil
experiment with mismatched coils. You can change the wire. Smooth any possible snags with 600-grit sandpaper or
number of turns to create different DC resistances and vary a fine emery board. Once they’re cleaned up, use a pencil to
your styles of winding to produce uniquely interesting, great mark the top side of each bobbin for reference. Unlike a full
sounding pickups. size humbucker bobbin, a mini humbucker doesn't have a
specific top side so it doesn't matter which side you mark.
Cut the each of the two 28AWG lead wires (4" long, one
black/one white) into 2" pieces (each coil gets one black
and one white lead wire). Strip 3/16" of insulation from each
end of these wires.
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Winding
Attach the bobbin to the winding machine with the marked
top facing out. Make sure it is carefully centered for wobble-
free operation.
Solder the black lead to the start tail and tape the joint using
coil tape. Do the same with the white lead and the finish tail.
1
There's no need to strip the clear insulating coating from
the fine coil wire; the heat from soldering will melt it away.
Wind 42 AWG coil wire around the bobbin by hand, giving
it about six turns counterclockwise, leaving a 3" tail. This tail
will be the pickup’s start lead; carefully tape it to the platen
of the winder, keeping it taught so it’s out of the way of
your winding.
Gibson mini humbuckers were
wound counterclockwise (when
viewed from the top of the pickup).
bo
Set the traverse limiter on your
bb
in
winder so the coil wire stops about
.020" from the flatwork on both
sides. This helps keep the bobbins Wire is wound
from deforming and gives a more counterclockwise
3
uniform coil.
When you have reached your desired wind count (typically Give the bobbins a few wraps in paper coil tape to secure
5,000 to 5,500 turns), carefully lift the tape fastening the start the lead wires. This is delicate work; be very careful not to
lead. Leave the tape on the wire to identify it as the start tail. break the leads as you wrap.
Cut the wire coming from your source spool, leaving a 3" tail. Repeat these winding steps for the other coil: same winding
This is your finish tail. direction, same number of turns.
Wrap the bobbin with a single layer of paper coil tape. This
keeps everything in place and protects the coil when you
solder the hookup leads.
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Assembly
4 8
Holding the baseplate with a vise or clamp, solder on the Attach wooden spacers to the bottom of the steel plate.
hookup wire. Use tiny dabs of superglue to help hold these in place.
5 9
Install the magnets in the bobbins, one with south facing up, Solder the two white leads together, tape off the joint and
the other with north facing up. The north-up bobbin will go tuck the wires in between the bobbins. Solder the black
on the side that is over the hookup wire. Give both bobbins start lead of the south up coil to the hot, center lead of the
a wrap of tape to hold them together. hookup wire.
6 10
Center the bottom steel Finish by soldering the start of the north coil to the braided
plate under the coils. A bit shield of the hookup wire.
of melted wax will hold it in
place. This also helps keep it
from vibrating against the
coil and causing feedback. 7
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11 14
Carefully tuck all wires out of the way to make room for the The cover on a Firebird mini humbucker holds the whole
pickup cover. pickup together. Carefully place the assembly into the cover
and use a clamp to ensure a tight fit from front to back. Use a
second clamp to gently squeeze the sides of the cover to fit
tightly against the baseplate. With a hot soldering iron, put
one small dab of solder on each side of the cover to secure it.
Wax potting
Much of the signature tone of ’60s Firebird pickups
comes from their steel plates and magnets, but high volume
can cause these parts to vibrate and produce feedback. So
we recommend potting your Firebird pickup in wax after it’s
assembled. (Gibson started potting their Firebird pickups
sometime in the 1980s.)
12 Your assembled pickup is ready to be installed in our metal
Firebird-style mounting ring or tapered plastic Epiphone-
Position the top steel plate 3/16" from the edge of the style mounting rings.
treble side of the magnets. You can scribe a line across the
bobbins for reference. A few small drops of melted wax on
the bobbins will help hold this piece in place and prevent
it from vibrating.
15
13
Use a file to rough up the cover in the areas where you will
be soldering. This will help the solder grip better.
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