BEFORE YOU BEGIN
NOT FOLLOWING THIS MANUAL WILL VOID YOUR WARRANTEE.
FAILURE TO SEND IN THE WARRANTEE CARD WILL VOID YOUR WARRANTEE.
• Be very careful when handling the tone arm. The internal arm wire is exposed at the
headshell and at the rear of the arm. This wire is very delicate and contains 64
strands of very pure copper. Physical damage to the wire is not covered by the
warranty after the arm is removed from its box.
• Please do not touch the unipivot bearing parts. Finger oils on the bearing cup in the
upper bearing housing or on the lower pivot point in the arm base assembly can
cause blemishing of the bearing and possible corrosion. Also, the point is sharp, be
careful.
• There are a number of setscrews on the JMW Memorial Tone Arm. The Allen
wrench that comes with your arm will only fit the setscrews that you will need to
adjust. All other screws are factory set and should not be adjusted, except by our
trained technicians. Resetting any of the factory settings is not covered by the
warranty.
DO NOT PUT THE DAMPING FLUID IN THE ARM UNTIL YOU
ARE FINISHED WITH ALL THE ADJUSTMENTS
UNPACKING YOUR JMW MEMORIAL TONE ARM
• This instruction manual was lying on a large foam pad. Remove the pad and put it
nearby on your work surface.
• You will now see a number of things in plastic bags:
• A bottle of arm damping fluid
• Allen wrenches
• Hex nuts, and washers (for cartridge mounting)
• Arm mounting and alignment tool
• “Q” tip
• Shure stylus gauge
• Take all these items out and set them aside. Be careful with the damping fluid. It
should be kept sealed until it is used.
• You will now see a thick foam pad hiding the things you really want to get at. Reach
between the pad and any one side of the box, lift the pad out, and set it aside as
well.
• You can now see the arm tube and counterweight, with its delicate 4-color wire and
Lemo connector, and the arm base assembly. If your arm is pre-mounted on a tone
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arm board, remove the small foam piece covering the "front" of the arm board. Set it
aside with the other packing material.
• Now, here's the hard part. Leave the arm tube and arm base assembly where they
are -- safe in their packaging.
MOUNTING THE JMW MEMORIAL TONE ARM
Below, you will find two separate sets of arm-mounting instructions.
The first set is if your arm's base assembly has come pre-mounted on a tone-arm
board.
The second set covers mounting the arm on your own "blank" tone-arm board.
Procedure for pre-mounted arms:
• Locate the instruction manual for your turntable, follow its instructions, and remove
the existing tone-arm board. If there is an arm on the board first detach the arm
wiring from the arm and turntable ground. Handle everything with extra care and put
board and arm in a safe place.
• Take the JMW’s arm base assembly/arm board carefully from its foam padding and
mount the board (with base assembly) onto your turntable, according to the
turntable's instructions.
• Now that the arm board with the arm base assembly is on the turntable, please go to
page, Final Assembly, and follow the steps there.
Procedure for mounting base assembly on tone arm boards:
• Note: during this procedure you will need a piece of sharpened chalk and a drill
with a 3/16" bit. You may wish to place these items conveniently near by.
• Attach the arm board to your turntable. Place the arm's base assembly on the rear
of the arm board. The connector block must be at the rear of the board.
• Take the Alignment Jig and, with the writing facing up, place its hole over the
turntable's spindle. Align the jig as shown in Fig.1. If the jig does not lie flat or it
does not reach the male bearing well, loosen the screw that is shown in Fig.2 and
move the boomerang shaped part of the arm until the bearing just touches the jig. It
may be difficult moving the boomerang but it is worth the effort for proper alignment.
• Keep the male bearing well in contact with the jig and move the base assembly until
it is in a suitable position on the arm board. See figure 1 for more details.
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• If you wish, the arm tube may be placed in position on the lower bearing to get a
better idea of how the whole arm will look. After the position is decided upon, place
the arm tube back in the box. Be careful not to damage the arm wiring.
• Holding the base assembly firmly in place, take a piece of pointed chalk and trace
the outline of the base onto the arm board. This will allow you to pick up the base
and place it back into position again.
• Pick up the base assembly and turn the arm-height knob counter clockwise until the
lower bearing assembly comes off the base. Be particularly careful as the bearing
assembly reaches its maximum height. Give it support, so that the two guide rods
and the internal screw are not stressed or damaged.
• Place the upper bearing assembly on its side on a cushioned surface. There will be
some lubricant on the internal screw so putting it on its side will prevent any mess.
• Put the base back on the arm board exactly within the chalk outline. Using a sharp
pencil, mark the outline of each of the three mounting holes on the board.
• Set the base aside and remove the arm board from the turntable
• Use a 3/16" bit to drill a hole through the center of each of the three hole outlines.
These three holes need to be perfectly perpendicular to the board's surface. We
strongly recommend using a drill press to achieve this. An alternative is to use one
of the drill guides available for use with a hand electric drill, which keeps the drill
perpendicular to the work surface. Wipe the chalk from the arm board.
• Fasten the base to the arm board with #6-32 X I" Phillips machine screws and
captive lock washer hex nuts. The nut's lock washer must go against the underside
of the board. Make the screws good and tight without stripping the threads. The
side of the base should be parallel to the side of the armboard or the side of the
turntable base.
• If the arm board is too thick for the I" machine screws, you can countersink the nuts
by using a 3/8" forstner drill bit which must be used in a drill press (the lock washer
needs a flat bottom to grab). Otherwise, you can buy longer #6-32 screws at your
local hardware store.
• Refasten the arm board to the turntable following the turntable's instruction manual.
• Carefully place the upper bearing assembly back on the base. Align the guide rods
with their holes and, while supporting the assembly, turn the knob clock-wise to
engage the internal screw. Do not force the screw if it does not engage easily. Back
it off and try again. Lower the bearing assembly to its approximate original position.
• You may have noticed that the screw holes in the arm board are larger than those in
the base. This is to allow for the marks on the board to be slightly off. You will now
compensate for any small difference in the position of the base.
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a. On the platter side of the support platform for the lower bearing, lift
mechanism, and arm rest, is a setscrew. Using the supplied hex
wrench, loosen this setscrew slightly.
b. Once again put the Alignment Jig into position as you did in steps 3
and 4 above.
c. Rotate the support platform as needed to bring the bearing well
securely into the cutout on the Alignment Jig and tighten the
setscrew. Please, just make it tight and don't overdo it. There is a
nylon tip on the set crew and it should not be crushed.
d. Put the jig away for now.
FINAL ASSEMBLY
A. CARTRIDGE MOUNTING:
• Remove the arm tube from the box (taking special care not to strain or damage, the
delicate 4-color wire and Lemo connector) and place it right side up on the foam
pad.
FOR CARTRIDGES WITH THREADED MOUNTING HOLES:
• Use the screws supplied by the cartridge manufacturer to mount the cartridge. Any
other screws may not fit the thread properly and may even damage the threads and
cartridge. USE ONE OF THE SUPPLIED WASHERS UNDER THE SCREW HEAD.
• For all cartridges with pass through mounting holes use the hardware supplied with
the arm. Remember to use the washers under the screw heads to prevent damage
to the finish on the JMW arm.
• In this step, the connectors will be attached to the cartridge's terminals. Disregard
the color of the insulators on the cartridge clips.
THE COLOR CODE OF THE WIRES IS AS FOLLOWS:
RED = right hot WHITE = left hot
GREEN = right ground BLUE = left ground
IF YOUR PHONO SECTION INVERTS PHASE, THE HOT BECOMES
THE GROUND COLOR
• The arm tube should be on its side on the foam pad when doing this.
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• Using tweezers or fine tipped pliers, grip the center of the red wire's connector (do
not grip the wire) and push it onto the cartridge's right hot terminal pin. In the same
way, connect each of the remaining connectors to its respective cartridge terminal.
Do not push the connectors all the way on, as this could damage the cartridge.
Always back up the cartridge with your finger when pushing on the clips.
B. THE COUNTERWEIGHT:
• The JMW tone arm comes with one large counterweight installed on the rear shaft of
the tonearm. For most cartridges you will only need this large weight. The
counterweight is held in position by a setscrew.
• Pick up the arm tube, taking care not to strain or damage the fine 4-color wire and
Lemo connector.
• For now, position the large counterweight as close to the bearing housing as it will
go (toward the front of the arm) but not touching the balance ring. The object here is
to balance the arm while keeping the counterweight as close to the bearing housing
as possible. This results in the least inertia for a given cartridge weight.
• In some rare cases it may be necessary to use two counterweights together.
Contact your dealer if a second counterweight is needed.
C. BALANCING ARM: TRACKING FORCE AND AZIMUTH
• Place the arm tube assembly on the lower bearing, taking care not to strain or
damage the 4-color wire and Lemo connector. Place the arm in its rest.
• At the rear of the arm base assembly is the connector block. Plug the Lemo
connector into its receptacle on top of the block. Notice that the connector can plug
in only one way. Align the red dots on the arms plug with the red dot on the
receptacle. Push gently, do not force the plug.
• Depending on the twist given to the wire when the plug was inserted into the box,
the arm will have a tendency to swing inward or outward when it is in neutral
horizontal balance. Later on, you will adjust the wire's twist to provide slight antiskating compensation.
• Make sure the turntable is level. Refer to your turntable instructions and use a
bubble level to check level. In most cases, the best place to put the level is on the
platter.
With a unipivot arm it is particularly important to level the turntable. This insures
that the damping fluid will not even come close to overflowing its well.
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• Move the counterweight until perfect neutral balance is achieved. Disregard any
tendency for the arm to float laterally. Make sure the arm is in neutral balance. Do
not go crazy.
• Next, the lateral balance or azimuth must be set. Because the phono cartridge is
offset, there is an unbalancing force that tilts the arm to one side. For the cartridge
to properly track the record groove, the stylus must be ninety degrees to the record
surface. Move the counterweight so a slight tracking force is applied and the stylus
just sits on the record surface.
• At the bottom of the arm tube (upper) bearing housing is a ring with one flat section.
Rotate this ring (see figure below) as needed to bring the arm into correct lateral
balance. When the azimuth has been set, you can lightly tighten the setscrew
located on the side of the ring. To make this task easier make sure the armtube is
parallel to the record surface. Lay the long thin tube in the notch in the headshell
and use it as a guide for setting azimuth.
Long thin rod
90 degrees
AZIMUTH BALANCE RING
TIP! The arm will tilt away from the flat portion of the ring. Turn the flat towards
the side of the arm that is hanging down.
• Unlike other unipivot arms, the JMW’s lateral balance weight does not hang off to
the side of the arm. Instead, its position around the bottom of the upper bearing
housing places the weight below the pivot point. This increases mass below the
pivot and increases arm stability.
D. TRACKING FORCE:
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• Tracking force is adjusted by moving the counterweight forward and back just a bit at
a time. At least initially, you will be setting the tracking force twice. The first time will
be before the cartridge's overhang is set. After this is done, you will need to double
check the tracking force and adjust it as needed.
• The JMW 10.5,12.5 does not have a built-in tracking force gauge, but a Shure Stylus
Force Gauge is supplied with your unit. Following the gauge instructions set the
tracking force to the cartridge manufacturer recommendation plus 1/10 of a gram
more. We always recommend going to the high side when it comes to tracking
force. High frequency vibrations can cause a light tracking cartridge to cause more
damage to the grooves than running a cartridge at a heavy setting. Make sure the
damping fluid is not installed when setting this force.
E. ANTI-SKATING:
• One of the least understood forces acting on a tonearm is anti-skating. Skating
force is created by friction between the stylus and the record creating a force vector
in a direction towards the center of the record. Putting a stylus down on a flat
grooveless record will cause the arm to shoot in toward the center of the record. For
years arm manufacturers have been trying to compensate for this force knowing full
well that it is impossible. The force is constantly changing as the music and the
velocity changes.
• A pivoted arm without an offset head would not be subject to skating force.
However, it will also have no correction for tracking error and the resulting distortion
is unacceptable. As soon as the arm's head is offset to lower tracing distortion,
skating force arises. Greater offsets result in greater skating force.
• After very careful listening tests we have determined that every tonearm we tried
sounded better with their mechanical anti-skating disabled and the tracking
force very slightly increased. All mechanical anti-skate devices add a negative
sound to the music because they are made of parts that can vibrate. We solve the
problem in a unique way:
• As mentioned earlier, the arm wire applies the anti-skating force. The degree of
force applied can be adjusted as explained below.
• To increase or decrease the amount of anti-skating force applied, simply unplug the
Lemo connector and twist it in the direction you want the force applied.
• For example, to increase anti-skating force give the connector a counterclockwise
twist. Likewise, to decrease the force, give the connector a clockwise twist.
Remember, the Lemo connector can only be "adjusted" in increments of whole
turns. If it is not, its key will not line up with the groove in the receptacle.
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• We could go on discussing the pros and cons of how much anti-skate is correct, but
the sonic answer is very simple. Adjust the wire as mentioned above until the
tonearm drifts outward when set to neutral balance. When you push the neutral
balance floating tonearm towards the center of the record, it should push back out
towards the rim of the record. Very little force is needed to do this, and the wire acts
like a spring to supply this force.
• If you try adjusting the anti-skate with a grooveless record you will ruin the twist in
the wire and void your warrantee
• This is all you need for anti-skating.
F. OVERHANG ADJUSTMENT:
• This adjustment will yield the lowest overall distortion when playing a typical 12"
record. Do not go crazy over this adjustment. You do not know if the stylus is
aligned properly on the cantilever. You are also facing a constantly moving target
when playing a record. The arm is moving in 3-dimensions and will only
approximate the accuracy you have built into your alignment.
• Place the Alignment Jig into position by sliding the narrow end with the circular
cutout between the arms lateral balance weight and the platform that supports the
armrest. Make sure that the jig's cutout fits against and around the bearing well.
• While holding the one end against the bearing well, swing the other end (with the
hole) over the turntable's spindle so that the spindle holds the jig in place.
• While the arm is in its rest, loosen the screws that hold the cartridge just enough that
the cartridge can be moved back and forth.
• Carefully swing the arm over the grid at the far end of the jig and place the stylus as
close to the dot in the center of the grid as possible. Using a lighted magnifier will
make this job very easy.
BE VERY CAREFUL NOT TO DAMAGE THE CARTRIDGE'S STYLUS:
• Move the cartridge so that the stylus rests on the dot. Now, viewing the cartridge
from above, line it up so that its sides are symmetrically positioned between the lines
of the grid. If the cartridge has parallel sides, these should be made parallel to the
grid lines. Also make sure that the cartridge is centered between the sets of lines.
Follow figure 3 in the back of the manual.
• Double check the adjustments made above. The cartridge needs to be both
centered and "square" between the gird lines and have the stylus resting on the dot.
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• The alignment gauge does not have a hole or dimple to hold the stylus. While the
printed dot makes it harder to keep the stylus in place, this method was chosen to
avoid the possibility of damaging the stylus cantilever or the diamond tip as the
cartridge is positioned.
• Place the arm back in its rest.
• Without letting the cartridge move, tighten the screws holding the cartridge to the
arm head. Make it tight, but don't over do it and strip the threads or distort the
cartridge body.
• Double check the horizontal balance, lateral balance, and tracking force and adjust
as needed. Increase the tracking force by 1/10 of a gram above the cartridge
manufacturers highest recommended force.
G. ARM HEIGHT:
Unlike many tone arms, the JMW's height is both easy and repeatable to vary. The
knob next to the bearing housing bears a scale numbered from zero to ninety-nine.
Below the knob there is an index mark engraved on the front of the support pillar.
Rotating the knob clockwise lowers the arm and rotating it counterclockwise raises it.
Set the arm height as follows:
• Start the turntable and place a record on it. Lower the arm onto the record and
make the arm tube parallel to the record surface by rotating the arm-height knob as
needed.
• This is a good initial setting. You may wish to vary it depending on the cartridge you
are using and or the particular record being played. The knob's scale makes it easy
to return to a previous setting by making a note of the number above the index mark
and the number of complete turns taken.
• The old wisdom, which had the arm tube parallel to the record surface, assumed not
only that all cartridges had the same internal geometry and stylus rake angle but
also that all records were cut with the same equipment set the same way. The idea
was that everything would line up properly with the arm parallel to the record.
• In the real world, things are never that simple. In any given cartridge/arm/record
combination one or more of the above assumptions are usually false. So what to
do? Well, you could spend countless hours analyzing the internal construction of
your cartridge, the stylus tip geometry and its contact angle with respect to the
record groove. In the analysis, you must also include the particular record you wish
to optimize for -- the angle at which the cutting stylus was set, the internal
construction of the cutter head, the depth of the groove, coefficient of friction of the
plastic, deformation under load, characteristics of the plastic, and more.
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• Once you have all this information, it becomes possible to adjust arm height for
minimum distortion of the signal generated by the cartridge. On the other hand...
• If you have a gentle touch (so as not to bounce the turntable) you can simply vary
the arm height while listening to the record and the changes in distortion that results.
Depending upon your patience and other mental factors, you could go through this
process for every record you own. Or, as most of us do, you can find a setting that
works for most records and sit back and listen to the music.
• Its up to you. We provide the means, you do what satisfies you the most.
• On the platter side of the adjustment knob's housing are two setscrews. The top set
screw may be tightened to lock in the setting. This setscrew has a nylon tip. Don't
make it so tight as to crush that tip.
H. ADDING DAMPING OIL:
• Among the things you unpacked earlier was a "Q" tip. Take this and sweep out the
well around the pivot in the arm base assembly. After this is done, throw out the
swab.
• Find the bottle of special damping fluid. Remove its cap and put in enough damping
fluid to fill the cup 3/4 full. (Do not add more fluid than called for. If the well is
overfilled, fluid will overflow when the arm tube is set in place.)
• The amount of fluid damping needed is very dependent on the amount of damping
that the cartridge cantilever has. A heavily damped cartridge needs less damping
fluid than a cartridge with only minimum or no damping. Try experimenting with fluid
levels if you feel the sound to be constricted (overly damped), remove some of the
fluid. If the opposite applies, add some fluid for greater damping.
• MISTRACKING IS USUALLY CAUSED BY FLUID THAT IS TO THICK. DURING
COLDER MONTHS YOU WILL GET MORE CONSISTENT SOUND IF YOU THIN
OUT THE FLUID IN THE DAMPING WELL. ADD TWO DROPS OF 40 WEIGHT
MOTOR OIL TO THE FLUID AND MIX THEM TOGETHER.
I. CONNECTING TO THE PREAMPLIFIER/AMPLIFIER
• ONLY USE INTERCONNECTS THAT ARE SHIELDED AND PROPERLY GROUNDED. NONSHIELDED INTERCONNECTS CAN HUM AND PICK UP RF.
• The connector block at the rear of the arm base has, in addition to the Lemo
receptacles two phono receptacles and a ground connector.
• Plug one end of the output cable into the phono jacks. The jack with the red ring is
the right channel and the jack with the black or white ring is the left.
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• Plug the other end of the cable into the turntable inputs on your prepreamplifier,
preamplifier, or integrated amplifier as appropriate.
• The ground connection is available to eliminate hum if necessary. If hum is present,
first connect a ground lead from the connector block to the preamplifier or amplifier
to which the output cable is connected. If this does not eliminate the hum, run a
ground wire from the turntable chassis to the connector block as well. The block's
connector will accept bare wires, spade lugs, or ring tongue connectors.
THE WARRANTEE ON THE JMW-10.5, 12.5 IS FIVE YEARS
PARTS AND LABOR. MISHANDLING OR MODIFICATIONS
VOIDS THE WARRANTEE.
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A
FIG. #1: THE PROPER WAY TO USE THE SUPPLIED ALIGNMENT
JIG. THE JMW-10 AND 12 ARE DONE THE SAME WAY.
ADJUSTMENT SCREW
FIG #2: IF JIG DOES NOT LIE FLAT OR THE BEARING IS NOT
TOUCHING THE JIG, LOOSEN THE BOTTOM SCREW ON THE VT
BARREL AND ROTATE THE ARM UNTIL IT LOOKS LIKE FIG. #1.
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FIG #3: THE PROPER WAY TO ALIGN A CARTRIDGE WITH THE
GRID OF THE JMW ALIGNMENT JIG. ALIGN THE CARTRIDGE, NOT
THE TONEARM HEADSHELL!
SET SCREW
FIG#4: IF THE VTA KNOB SHOULD EVER LOOSEN UP, BACK OFF
THE SET SCREW SHOWN, PUSH DOWN ON THE KNOB AND
RETIGHTEN THE SET SCREW.
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FIG #5: USE THE LONG WIRE ROD TO HELP YOU SET PERFECT
AZIMUTH ADJUSTMENT.
FIG #6: THE SETSCREW LOCATED BETWEEN THE ARMREST AND
THE ARM LIFTER IS USED TO MAKE THE ARM TOTALLY RIGID.
LIGHTLY ENGAGE THE CHASSIS WITH THE BLACK HEAD OF THE
SCREW WHEN YOU ARE THROUGH MAKING ADJUSTMENTS.
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