Kuzma Cartridge User Manual

APPENDIX 1

Tangential Cartridge geometry adjustment

Once the cartridge has been mounted, it is necessary to ensure that the cartridge is tangential to the
record grooves in order to minimize tracking distortion during playing. As the cartridge moves in an
arc across the record, tracking distortion occurs and is minimized by the tonearm geometry and the
angle of the cartridge in the headshell.

With optimum tonearm geometry, very low distortion levels (below 1 %) can be obtained across the
entire playing surface. Cartridges have zero distortion at two points on a record and these points are
used when aligning the cartridge. In practice these points lie at 66 mm and 121 mm from the record
centre (see protractor). Other protractors make use of different zero points due to the use of different
parameters in calculation. In this case 60 mm has been chosen as the inner groove and 146 mm as the
outer groove which still has optimum tracking distortion.

1. Ensure bias is on minimum or switch off.

2. Place protractor over spindle on platter.
Note:

If you have difficulty seeing the cantilever it may help to raise the arm a few mm, taking care that the
protractor does not rotate. This also prevents tilting of the cantilever due to the effect of bias force. It
may also be helpful to fix the platter by inserting a wedge between platter and plinth and by inserting a
sheet of white paper to give a clear background while observing the cartridge. Use a strong light.

3. Alignment at zero point 66 mm (A):

Place tip of stylus on point A (ie. zero point 66 mm). With a strong light observe cartridge from front.
The cantilever and the line on protractor should be in perfect alignment.
If the cantilever is not, then the body of the cartridge will have to be rotated slightly.
Do not adjust cartridge by observing body of cartridge only. (Fig.14)

Fig. 14 Alignment at A

To rotate or readjust cartridge:

4. Slightly loosen the screws which attach the cartridge to the headshell.

5. Holding headshell in one hand slightly rotate the body of the cartridge.

6. Recheck alignment at position A and continue adjustment until line described in point 3 is achieved.

7. Alignment at zero point 121 mm (B):

Reposition protractor and check alignment at position B.

Fig. 15 Alignment at B

8. If the cantilever is not in alignment then rotate protractor until it is in alignment somewhere along
the line “x-y” though stylus will probably not be at zero point B. Raise the cueing device a bit for
better viewing. (Fig.15)

9. If stylus is in front of point B, pull the cartridge forward (along side) in the slots of the headshell for
approximately the same distance “S” as stylus is overhanging zero point B. If it is behind point B,
push cartridge backwards towards the pivots of the tonearm for distance “S” (Fig. 16)

“S”

“S”

B

0%

Fig.16 Stylus tip is in front of zero point B.

10. Now rotate protractor and again position stylus at zero point A as described in 5 and 6
above, ensuring that the position of the cartridge in the slots alongside is not changed but only rotated
for alignment of the cantilever in zero point A. (Fig.17)

Fig.17 Rotation at A