VPI JMW-12.6 Owners manual

JMW 12.6

MEMORIAL TONEARM

SETUP AND INSTRUCTION MANUAL

VPI IND. INC., 77 CLIFFWOOD AVE #3B, CLIFFWOOD NJ 07721

PHONE: [phone], FAX: [phone]

www.vpiindustries.com

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SETTING YOUR JMW MEMORIAL TONE ARM

• You will see a number of things in plastic bags:

• Allen wrenches

• Hex nuts, and washers (for cartridge mounting)

• Arm mounting and alignment tool

• Shure stylus gauge

• Take all these items out and set them aside

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.

• 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.

B. THE COUNTERWEIGHT:

• The JMW 12.6 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.

• The counterweight is used for setting the azimuth (lateral balance) of the
cartridge and the vertical tracking force.

• For now, position the large counterweight to give a minimum of tracking force,
just enough force to keep the cartridge on the alignment jig.

• In some rare cases it may be necessary to use two counterweights together.
Contact your dealer if a second counterweight is needed.

C. OVERHANG ADJUSTMENT & ALIGNMENT

• 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.

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• 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 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 grid lines and have the stylus resting on the
dot.

• 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.

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• 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.

D. TRACKING FORCE:

• Tracking force is adjusted by moving the counterweight forward and back a bit
at a time. The 12.6 counterweight has a fine adjustment nut on the rear bottom
of the counterweight. Use it to really dial in the tracking force properly.

• The JMW 12.6 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 highest 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 make a light tracking
cartridge to cause more damage to the grooves than running a cartridge at a
heavy setting.

E. AZIMUTH

• 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.

• By rotating the counterweight you can tip the arm in either direction. Set the
counterweight so the cartridge sits as shown below.

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Long thin rod

90 degrees

E. ANTI-SKATING:

• 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.
The 12” arm has a very small offset angle and therefore a very low skating
force to deal with.

• 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, unwinding the coiled wire. 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.

• 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

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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 groove less record or a test record
you will ruin the twist in the wire and void your warrantee

• 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:

NOTE: THE TWO THUMBSCREWS MUST BE RELEASED
WHEN MOVING THE VTA KNOB. THE THUMBSCREWS
SHOULD BE TIGHTENED WHEN LISTENING.

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, rotating it counterclockwise raises it.

Set the arm height as follows:

• Place a record on the platter surface. 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. This is not true and the VTA should be adjusted for best sound in your
system.

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• Rule of thumb: Raising VTA lowers bass and increases treble. Lowering

VTA increases bass and decreases treble.

H. CONNECTING TO THE PREAMPLIFIER/AMPLIFIER

• ONLY USE INTERCONNECTS THAT ARE SHIELDED AND PROPERLY
GROUNDED. NON-SHIELDED 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.

• 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.

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