Moerch DP-6 Owners manual

H. H. MØRCH

MORCH

DP-6 Fitting instructions

• Contents of the packing

In the packing of the tonearm you will find the arm base in which the bearings are
encapsulated in a heavy body. This is the link between the moveable part of the tonearm and
the arm pillar, which is to be mounted in a bush in the board of the turntable.

Further you will find one arm tube according to the choice that you have had from literature
about the tonearm or from advice of your dealer. There also will be 4 weights, finger lever with
screws, knurled nut, hexagon spanner, and a syringe with silicone fluid.

The tonearm usually is supplied with the arm rest mounted on the pick-up lifter, but if desired
a separate arm rest could be supplied instead.

• Mounting the bushes

First it has to be decided exactly where to place the bush in which the tonearm is to be
mounted. The center of the bush should be at a distance of 212 mm (8 5/16 '') from the center
of the turntable platter and there has to be room enough for the counterweight rod to move
freely. The counterweight rod is having a rear overhang of 70 mm (2 3/4 ") as to the center of
the arm bush. If separate arm rest is used, it should be placed so that the arm when resting
on it is at a suitable distance from the record.

The mounting template on the packing of the tonearm is showing the position of the arm base
and the arm rest as to the turntable spindle. It should be noted that the position of the
turntable spindle shown is just an example. In order to allow for the most convenient position
of the arm base the turntable spindle could have its center anywhere on the arc shown.

Mark the center of the arm bush and check that the distance to the center of the turntable
platter is 212 mm (8 5/16 "). Then drill a 20 mm (13/16 ") hole with center in this mark. Also, if
separate arm rest is used, drill a 10 mm (13/32 ") hole for the bush for the arm rest about 155
mm (6 1/8 ") in front the 20 mm hole.

Fastening the two bushes: In order to make it easy to adjust the height of the arm and the arm
rest with the accompanying hexagon spanner, the small screws for fixing the arm and the arm
rest should point to the right.

Then the arm base is fastened in the arm bush.

• Mounting the cable to the amplifier

Put the grey plug of the accompanying tonearm cable into the socket below in the arm pillar. If
the turntable has a floating sub chassis, the cable should not be restricted in any way, and it
should be arranged in a suitable arc, so that it can not limit the free movements of the
suspension. Remember that the Y-shaped ground terminal should always be connected to the
chassis (ground terminal) of the amplifier. The chassis of the turntable may also have to be
electrically connected to the arm bush.

Page 1

• Choice of weights and putting them on

In order to make it possible to balance all phono cartridges the tonearm is supplied with three
counterweights - large, medium, and small - having the hole excentrically positioned and with
a tracking force weight having a centrally positioned hole.

The weights that are to be chosen for balancing a cartridge depend on which arm tube that is
to be used and on the weight of the cartridge.

The weights to be used can be found in the below table (tf. means tracking force weight).

At first the counterweight/s is put onto the counterweight rod and then the tracking force
weight. To put on the counterweight/s and to displace them along the counterweight rod they
have to simultaneously be revolved to and fro.

Weight of counterweight in grams when using: Counterweight size: Note:

Light arm tube Medium Heavy Extra Heavy
“Green” “Red” “Yellow” “Blue”

1.2-2.4 small only 1

2.5-6.5 0.5-4.3 small + tf. 2

5.2-7.6 3.0-5.4 0-2.2 medium + tf.

7.6-12.7 5.4-10.2 2.6-8.2 medium + small + tf. 2

9.0-9.9 7.0-7.6 4.1-5.0 large + tf.

11.9-21.2 9.9-15.4 6.7-11.3 0-4.8 large + small + tf. 2

19.0-21.2 17.0-19.4 14.0-16.2 6.5-9.0 large + medium + small + tf. 2

Notes:

1. Here the small counterweight is used as tracking force weight.

2. Here both the tracking force weight and the small counterweight are used as tracking
force weights. Each of them gives 1/2 gram of tracking force when slid 1 indentation
forwards.

With heavy cartridges or if large tracking force is needed the medium or the large
counterweight should be used as tracking force weights as well. The medium
counterweight gives 1.2 g and the large counterweight gives 2 g when slid 1 indentation
forwards.

Thus a certain tracking force can be obtained by sliding more than one weight adding up
their shares of tracking force.

• Refilling the silicone fluid

The accompanying syringe contains about 0.6 ml of silicone fluid (60 units). At first the pick-up
lifter should be filled in. Pull the black piston out of the lift cylinder and place it in a completely
clean place. Then inject 0.1 ml (10 units) of the fluid behind the shaft inside the lift cylinder.
When doing this, the lift handle must be in "lowered" position. When the fluid is injected, the
tip of the syringe is "wiped off" on the shaft, and the syringe is pulled up with a little jerk there­by preventing the fluid from getting in touch with the walls of the lift cylinder. Do not put the
piston back into the lift cylinder until the silicone fluid has merged down to the bottom of the

Page 2