Kuzma 313VTA, STOGI REF 313VTA TONEARM Instruction Manual

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KUZMA STOGI REF 313VTA TONEARM

Instruction manual Serial Number: …..

2009-11

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KUZMA LTD

INSTRUCTION MANUAL FOR 313 VTA tonearm

The Stogi Ref 313VTA tonearm is a very precisely engineered piece of equipment, however,
the construction is robust and requires minimal maintenance for optimal performance.

Fig.1

CONTENTS: Page

General description 3
Basic Setup 4
Setting up the tonearm 4-5
Adjustment of tracking force 6
Adjustment of tangential geometry 6
Adjustment of VTA 6
Adjustment of azimuth 7
Adjustment of bias 7
Adjustment of cueing device 8
Maintenance 8
Transport 8
Problems 8
Appendix 1 (tangential geometry) 9-11
Appendix 2 (fine azimuth) 12
Appendix 3 (fine bias) 13
Protractors 14

VTA tower&knob

VTA lock

azimuth lock

Cueing device adjust. azimuth adjustment Ring fixing

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General description :

The whole construction is mounted on a rigid VTA tower which allows very precise VTA
adjustment while playing, without any loss of rigidity, yet with up to 0.01 mm of precision
and zero play.

The main tube is constructed and machined from solid aluminium, similar to our tangential
Air line arm. The main counterweight balances the tonearm. Azimuth can be adjusted in
small repeatable increments with zero play, by means of an Allen key.

A feature of the tonearm is a unique detachable headshell. The electrical connection is via
standard pins but the headshell can be simply removed by unscrewing with an Allen key. The
headshell is fixed with a precise hexagonal locking system giving the same rigidity as with a
fixed headshell. The tonearm itself is mounted in the standard position, despite its longer
effective length.

Technical data:

Mass: 1700 gr
Effective length : 313 mm ( 12,3 inch)
Mounting distance: 212 mm
Offset angle: 17.50 degrees
Distance from spindle to
horizontal bearing: 300 mm
Effective mass: 13 g
VTA adjustment: yes
Azimuth adjustment: yes
Bias adjustment: yes
Cables: single
Arm mount: Kuzma-Air line

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1. Unpacking

Open the box carefully and remove the top covers.
First remove the armbase and prepare it for fixing onto the turntable. Be sure that the
armboard on the turntable has the correct cut-out (main central hole must be 40 mm in
diameter).

2. Basic set up

Armbase:

Mount the armbase on the turntable. If the pre-cut has a thread, then use three screws and fix
them from the top through the armbase into the armboard thread. A second way is to use a
ring underneath and fix three screws into this ring, which will then hold the armbase very
tightly. Be sure that you position the armbase so as to give access to an Allen key for fixing
arm into the armbase (towards the back of the turntable). Also check, when mounting the arm
on other turntables, that you allow enough clearance for counterweights and correct position
of the tube in relationship to the platter.

VTA arm tower:

Insert the VTA arm tower into the armbase. Ensure that the height is such, that the bottom
surface of the platform holding the cueing device is at the same height as the record. Fix it
with an Allen key. Also check that the VTA adjustment is in the middle position, to allow fine
VTA adjustment up and down 5 mm each way.

With 1.5 mm Allen key, release the small ring which is on the fixing pillar below the VTA
arm tower. Now it will drop down and touch the armbase. Fix the ring again and release the
VTA arm tower. You now have the correct height but you can freely rotate the VTA arm
tower horizontally. Rotate it to such a position that the distance from the centre of the record
to the centre of the horizontal bearing is 300 mm. Now fix VTA arm tower.

3. Setting up the tonearm

Connecting tonearm:

Check the horizontal movement of the tube to ensure that the headshell will reach the inner
grooves.
Due to the high tonearm mass, turntable levelling and suspension should be checked and
adjusted according to the turntable manual.

Cartridge mounting:

Mount the cartridge with the appropriate set of 2.5 mm screws and check its travel above the
record with cueing device in upper position!

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Headshell removal and fixing:

This tonearm has a detachable headshell and fixing and positioning it has no negative effect
on tonearm performance. The whole headshell is fixed with one Allen key 2 mm. Insert it in
the top hole and release screw with Allen key for at least one turn (ACW). (Fig.2&3)

Disconnect cartridge pins, remove Allen key and pull out the headshell. (Fig.4)

Fix the cartridge and return headshell back in to the tube. If it can not be inserted easily,
rotate the screw a little more in ACW direction. Then fix it back in CW direction with gentle
force, around one turn.

Fig.2 Locked Fig.3 Unlocked

Note: Do not over-tighten the screw which locks the headshell.

Fig.4 Removing headshell

Balancing of the tonearm:

Fix cartridge pins. Balance the tonearm to zero tracking force by rotating counterweight along
the thread.