Instruction manual KUZMA STOGI REFERENCE TONEARM (with Stabi Ref turntable) Serial Number: ….
KUZMA LTD INSTRUCTION tonearm MANUAL FOR STOGI REF The Stogi Ref tonearm is very precisely engineered pieces of audio equipment. However the construction is robust and requires minimal maintenance for optimal performance. Azimut fixing Azimut adjustment Fig 1. CONTENTS: Page 1.0. General description 2.0. Unpacking 3.0. Tonearm Setup 4.0. Tonearm adjustment 4.1. Adjustment of tracking force 4.2. Adjustment of tangential geometry 4.3. Adjustment of VTA 4.4. Adjustment of azimuth 4.5.
1.0. General description: The Stogi Ref tonearm shares the same construction with Stogi arm. The main difference is that Stogi has a cylindrical and Stogi Ref a conical tube. The Stogi Ref has a very sophisticated, precise and repeatable azimuth adjustment mechanism with zero play and a very rigid locking mechanism. The main structure, conical tube and headshell are machined from solid aluminum blocks. The quality ball bearings are carefully selected and individually checked and tested before assembly.
2.0.0. Unpacking: 2.1.0. Packing list: Tonearm with fingerlift; counterweight; armbase; instruction manual; two protractors, one for mounting tonearm on turntable and the other for cartridge geometry adjustment and a bag. Bag: Sets of 3 socket head screws M6x16 mm, M6x20 mm, M6x25 (for Stabi Ref), M6x 30 mm, three washers, three spring washers (wooden armboards) for fixing base.
3.1.2. Armbase mounting: To fix armbase to armboard you will need the correct length of three socket head screws, washers and Alley key 5 mm. Fit washers on screws and insert into underside of tonearm board and up into tonearm base. Position base so that height adjustment (VTA adjustment) screw is at top right position, i. e. 2 o’clock and tighten screws using Allen key. Remember that the screws are of harder material than the armbase (aluminum) so do not over tighten as this could damage base.
3.3. Setting up the tonearm: 3.3.1. 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 leveling and suspension should be checked and adjusted according to the turntable manual. 3.3.2. Cartridge mounting: You will need Allen key 2 mm plus the two screws and nuts M 2.5 (some cartridges has already threads, nuts will not be need it). Mount the cartridge with the appropriate set of 2.
The counterweight is marked with five red dots. One full rotation of the counterweight increases tracking force by 0.5grams, therefore distance from one dot to another corresponds to 0.1 grams. With the cueing device in the ‘up’ position and tube in the armrest the counterweight is turned anticlockwise (from front view) to increase the tracking force. 4.0. Tonearm adjustments: 4.1. Adjustment of tracking force: 4.1.1.
If tonearm is too low, then the tonearm must be raised by releasing the screw in the base while holding the tonearm by the ‘C’ shape and lifting it up. Tighten VTA screw when the tonearm is in position, though do not over tighten. Repeat process until arm is high enough to clear record. The needle should be in the groove. If not the tonearm is too high and should be lowered. Note: Ensure needle is properly in the groove; observe cartridge body reflection on record surface.
Position B: Reposition protractor, place tip of stylus on point B (B- zero point 121 mm) and check alignment at position B in the same way as in position A. If the cantilever is not in alignment then rotate protractor until it is in alignment somewhere along the line ‘x y’ though not necessarily at point B. Raise the cueing device to see better. If needle is in front of point B, pull the cartridge forward in the slots of the headshell for approximately the same distance.
4.3. Adjustment of VTA: VTA describes the angle between the record surface and the stylus. This angle changes as the height of the tonearm is altered. The standard angle is 15° but cartridge manufacturers work with degrees of anything between 10°- 30° so only by listening tests can one ascertain the correct angle for your particular cartridge. The VTA also varies according to the tracking force and thickness of records. An increase in tracking force is equivalent to lowering the tonearm and vice-versa.
4.4.2. Fine Azimuth adjustment: Note: See appendix 2. The easiest way is to use an appropriate program with a test record and PC. It can also be done using an oscilloscope with a test record or by using good records in a good system and listening to the sound. Cartridges with fine profiles (VDH, Microline etc.) are more sensitive to this adjustment. On the other hand cheaper cartridges are not made so well, so making fine adjustment is also useful. Start listening with the tube in zero position, ie.
X mm 0 3 8 13 18 P gr 1.00 1.25 1.50 1.75 2.00 Fig. 6 Bias adjustment X bias lock For maximum trackability, it is advisable to set the bias by use of an appropriate test record, ie. those with tracking bands. Please do not use test records with blank space where the tip of the needle sits on the surface rather than in the groove. Set bias and tracking force as previously described and listen to mistracking on highly modulated tracking bands.
5.0. Maintenance: 5.1. General: The bearing does not need maintenance. Dust only with a soft brush, do not blow away dust. If the tonearm is mounted on a wooden armboard the base may need to be retightened to the board after a few weeks. 5.2. Checking bearings for play: Holding the headshell, gently try to rotate tube of arm. There should be no movement or audible clicking. If there is, consult your dealer. Note: Ensure that Azimuth and height adjustment screws are fixed before attempting the above. 5.3.
7.0. Troubleshooting: If any problems occur with your tonearm please do not hesitate to contact your dealer. Many audiophiles do, however, find it convenient to try and solve small problems themselves and, therefore, the procedures outlined below may be followed if such difficulties should arise. 7.1. Pin connector broken off wire: To repair this you will need a small soldering iron, non acid solder, tweezers, sharp knife, uncut end of drill or nail about 1.3mm dia.
is in a horizontal position, ie. maximum bias. Knot thread three times and trim surplus. If absolutely necessary the length of thread can be shortened by loosening screw at point ‘x’ with Allen key 1.5mm and pulling rod out slightly from main C metal part. 7.3. Hum and buzz: Check to ensure that grounding wire has been connected. If using an MC transformer, try connecting ground wire to this or to the preamplifier.
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.
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 121mm (B): Reposition protractor and check alignment at position B. Fig. 15 Alignment at B 8.
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) 11. Recheck alignment of the cantilever at zero point B. If cantilever is not aligned here, rotate protractor to find where on line “x- y” the cantilever is aligned again. (Fig.18&15) Fig.17 Rotation at A Fig.
Appendix 2 Fine Azimuth Adjustment This can be done using an oscilloscope and a test record or by using good records in a good system and listening to the sound. Cartridges with fine profiles (VDH, Microline etc.) are more sensitive to this adjustment. On the other hand cheaper cartridges are not made so well, making fine adjustment more useful. With an oscilloscope we measure the differences in crosstalk between both channels. The idea is that on both channels this is equally small.
Appendix 3 Fine bias adjustment 1. Set bias and tracking force as previously described and listen to mistracking on highly Modulated tracking bands on test record. On higher modulated bands mistracking can be heard as impure tones and there will be more overtones. (See instructions on test record) 2. If mistracking is apparent, increase or decrease bias until minimum mistracking is found.
A X Y B X Y S Cartridge Protractor (Not in correct scale) 21 Tonearm mounting protractor
