Kuzma turntables FAQ
2.00000. Kuzma turntables-general:
2.00101. What is the main difference between a suspended and solid supported subchassis turntable?
2.00102. Are special supporting isolation platforms effective under turntables?
2.00103. What is the main difference between different AC power supplies for Kuzma turntables?
2.00104. Why are there different thicknesses of washers supplied with turntable clamps?
2.00105. Which oil is used for turntables suspension damping?
2.00106. Where can I find the serial numbers on the turntables?
2.00201. What is the best support for turntables?
2.00202. How important is horizontal levelling of the turntable?
2.00203. How do I measure speed and make fine adjustments?
2.00204. How many bars per 20 seconds must pass a still reference point for 0.1% tolerance?
2.00301. Will the bearings in any Kuzma turntable be harmed if run without oil?
2.00302. Which oils are used in Kuzma turntable’s bearings?
2.00303. What should I use to clean and protect brass parts coated with lacquer?
2.00401. Will the turntable’s power supply (PS) benefit from the use of better power cords or support?
2.00402. Can the PS from Stabi Ref and Stabi XL be used on Stabi S?
2.00403. Can I convert the PS to different input voltages?
2.00501. Why is the platter (and the motor pulley) rotating in the wrong direction?
2.00502. Why is the platter rotating too fast?
2.00503. How do I test if the power supply is working properly?
Kuzma turntables:
2.10000. Stabi turntables:
2.10101. What are the main differences between the various older, solid oak models of Stabi turntable?
2.10102. Why is the bearing on my turntable slack when I move the shaft with the subplatter?
2.10201. Should I remove spike protective cups for best results?
2.10401. How can I add a power supply to Stabi?
2.10402. Can turntables be upgraded?
2.10403. Can I upgrade from a round cross section belt to a flat belt?
2.10404. Can I still get various pre-cut armboards?
2.10501. Can I get hinges for the older Stabi turntables?
2.20000. Stabi Ref turntable:
2.20101. Are different pre- cut armboards available for different tonearms?
2.20102. What maximum tonearm mass will the turntable accept?
2.20103. How many belts does Stabi Ref use?
2.20401. Is a dust cover available?
2.20501. Can I remove the Stabi Ref suspension towers?
2.20502. Is hum on Stabi Ref turntable unavoidable?
2.20503. What can I do if I have trouble levelling and adjusting suspension?
2.20504. Why can I hear noise below platter?
2.30000. Stabi S&SD turntables:
2.30101. Is it possible to mount different tonearms on the Stabi S turntable?
2.30102. Can I use Stabi S which is 50Hz, in an area with 60Hz mains voltage and vice versa?
2.30103. How I get 45rpm speed?
2.30104. From what is the chassis main T beam made?
2.30201. How important is the distance of the motor tower from the T beam?
2.30202. What is the best support for Stabi S?
2.30203. Where can I put he tonearm cable below T beam?
2.30301. How can I clean and protect the lacquered brass?
2.30401. Can Stabi S be upgraded to accept two tonearms?
2.30402. Can I add an electronic power supply?
2.30403. Can a 12 inch arm be fitted?
2.30404. Can I increase platter mass?
2.30501. What can I do if the motor slides towards the T beam?
2.30502. I can hear noise below the platter?
2.30503. Do the “O rings” need replacing?
2.40000. Stabi XL turntables:
2.40101. How many tonearms can be positioned around this turntable?
2.40102. Which tonearms can be mounted onto Stabi XL?
2.40103. Which tonearms can be mounted on a Stabi XL which has a tonearm tower without VTA adjustment?
2.40104. What are the differences between Stabi XL, Stabi XL2 and Stabi XL4?
2.40201. How important is the distance of the motor tower?
2.40401. There is not enough space on the Stabi XL tower to connect a 5PIN connector to SME or Graham arms?
2.40501. How can I cure a hum problem?
2.40502. What should I do if platter needs manual help to start up?
2.50000. Stabi M, XL DC, XL AIR turntables: Soon
2.00000. Turntables-general:
2.00101. What is the main difference between a suspended and solid supported subchassis turntable?
A solid turntable will have less movement between the motor and the platter so rotational transfer is better. In addition the tonearm does not move with the subchassis around the platter as on a suspended type of turntable. Vibration from the stand and motor are more easily transferred to the platter and tonearm with a solid support turntable. A combination of suspension with strong damping can achieve the best results and adding appropriate mass makes turntables less sensitive to external vibrations.
2.00102. Are special supporting isolation platforms effective under turntables?
Yes, but with suspended turntables care must be taken that platform resonance does not interfere with resonance in the turntable suspension bearing springs, rubber or air springs or in stand supports.
2.00103. What is the main difference between different power supplies for Kuzma turntables?
We use AC motors. In earlier models frequency and sine waves were generated with quartz and filters( Stabi, Stabi S PS, Stabi Ref, Stabi XL). Later versions (since 2008 Stabi Ref 2, Stabi XL2 & 4) use computer generated signals which need less filtering and have even better and finer speed adjustment.
2.00104. Why are there different thicknesses of washers supplied with turntable clamps?
The washer lifts the record above the mat and the clamp then bends the record down, pushing its outer perimeter firmly to the platter. Thicker records are stronger and less flexible and require a thinner washer. With thin, flimsy records we need more lift above the mat, hence a thicker washer.
2.00105. Which oil is used for turntable suspension damping?
Silicon oil remains stable almost all the time. The thicker the oil (higher numbers), the more damping there is. Stabi and Stabi Ref. turntable use 35.000 silicon oil.
2.00106. Where can I find the serial numbers on the turntables?
These are written on the packaging boxes.
Otherwise:
Stabi: remove the subplatter. It is hand engraved on the top surface of the nickel plated bearing housing.
Stabi S: It is on the label at the back on the shorter part of the ‘T’ beam.
Stabi Ref: It is inscribed below the platter on the top surface of the acrylic plate towards the rear of the turntable.
Stabi XL: remove sub-platter. It is on the outer wall of the oil guard. Since 2009 it is at the back of the base, towards the top.
2.00201. What is the best support for turntables?
A strong, rigid stand. If your floor is shaky, however, then such a stand will still move and might interfere with turntable suspension or tonearm resonance. In this case a light flexible stand might be better where the stands own resonance is higher.
Two thinner plates of different materials for a shelf, such as glass or stone are usually better than a single thicker one as they damp each other.
2.00202. How important is horizontal levelling of the turntable?
Most turntables are less sensitive than tonearms (see 1.0208). If the turntable is level, however, the tonearm is automatically levelled. If the platter is not level then bias forces and pressure in the grooves of the record will be different, though these are changing all the time.
2.00203. How do I measure speed and make fine adjustments?
Use a strobe disc, (these need correct indicators for 50 Hz or 60 Hz and main light, some modern lights are not suitable) or a special strobe clamp with light
Test records or strobe discs, which measure speed using stroboscopic bars, give accurate readings. If small fluctuations are seen, there is no need to worry as this is usually due to a badly pressed or warped record. The same applies with some strobe discs.
Speed is changed in small steps in power supplies. This is done after oil is added into the bearing and the platter has been spinning for a few hours at least or even 24 hours. See the turntable manual.
2.00204. How many bars per 20 seconds must pass a still reference point for 0.1% tolerance
7 bars pass in a given time a still reference point.
2.00301. Will the bearings in any Kuzma turntable be harmed if run without oil?
No, as we use a metal shaft made from fine carbon steel which slides along a special textile impregnated material. This absorbs some oil and is, therefore, never dry. It has excellent sliding, damping and low noise properties though it is not the easiest material to work with. The same applies for the sliding material against the supporting ruby ball.
2.00302. Which oils are used in Kuzma turntable’s bearings
Car engine oils are generally used as they last a long time and posses the correct properties. The most important factor is viscosity which is expressed as a number, where the last two digits indicate viscosity at normal temperatures. The first two digits indicate viscosity at low temperatures which is irrelevant for our purposes.
| Stabi LK1 – shaft with pointed bottom | Car engine oil | 5W-40 (or 15W-40) |
| Stabi LK2 - shaft with flat bottom | Car gear box oil | SAE 90 |
| Stabi S, Stabi Ref,Stabi R,Stabi M, Stabi XL | Car engine oil | 5W-40 (or 15W-40) |
| Stabi XL and XL4 since 2007, XL DC | Lubcom oil | OM-220 (from dealers only) |
2.00303. What should I use to clean and protect brass parts coated with lacquer?
The lacquer used has been baked at very high temperatures and is more resistant than the lacquer used on cars or wooden floors. Any lacquer treatment products can be used on these surfaces but, in practice, a damp cloth with mild washing up liquid is adequate. Do not use magic car lacquer repair kits.
2.00401. Will the turntable’s power supply (PS) benefit from the use of better power cords or support?
Yes. In addition try to reverse phase on the mains or add supporting feet.
2.00402. Can the PS from Stabi Ref and Stabi XL be used on Stabi S?
The electrical output from all our power supplies is 110V, dual phase 50 Hz, so all PS can be used on all turntables, (providing you have the correct motor connections).
Only Stabi S ( or older Stabi TT), made for the US ( 110V/60Hz), needs a special outboard PS version with 60Hz output. See also 2.10401.
2.00403. Can I convert the PS to different input voltages?
Yes. It can be done simply but only by a qualified electrician using information which we will supply. All PS will accept input from either 50 Hz or 60 Hz mains voltage. PS must be set up for either 100 – 130 V or 200 – 240 V.
2.00501. Why is the platter (and the motor pulley) rotating in the wrong direction?
The AC motors used, are dual phase synchronous motors. Two sine waves are in phase ( delay) in relationship to each other. This affects the motor direction rotation. If we reverse the phase then the rotation of the motor is opposite. If only one phase comes to the motor (due to PS failure) then the motor will have less power and rotation direction will be random.
2.00502. Why is the platter rotating too fast?
Stabi S: wrong mains frequency or the belt is not in the correct position on motor pulley.
Stabi Ref: the belt is not in the correct position on the motor pulleys.
Stabi Ref 2 & Stabi XL 2&4: check the belts or check the output frequency on power supplies PS REF2 or PS XL2- it should ALWAYS be 50Hz regardless of main frequencies. See also in Instruction manual under Problems as “wrong speed”.
2.00503. How do I test if the power supply is working properly?
Output should not be measured except by a qualified electrician who has read the service manual. If any measuring device, such as an oscilloscope, is connected, it must be electrically separated from the mains by a transformer!
To test the PS check motor power. Remove the belt and try to slow down pulley rotation with three fingers, until rotation practically stops. When it does stop it will vibrate. Do not hold for more than 2 – 3 seconds. If you feel very little resistance there could be one phase output failure which is giving less power to the motor. If you rotate the pulley in the opposite direction and start the motor up and it continues rotating in the wrong direction, this indicates PS output failure.
Kuzma turntables:
2.10000. Stabi turntables:
2.10101. What are the main differences between the various older, solid oak models of Stabi turntable?
The Stabi turntable as seen in photos on this website is of a totally different design to some of our earlier non-export turntables. In parts of the former Yugoslavia this model was called Stabi 2 (1985-2005) because the first Stabi was never exported. Outside of Yugoslavia there was only one Stabi. If you want to check which is which, see the following. The export model Stabi ( Stabi 2) should have three spiked legs for horizontal levelling and on top there should be 4 black levelling knobs with a silicon damped suspension and a rectangular shaped armboard. Also the subchassis is visible from the front. The older Stabi 1 turntable (1983-1987) has a closed subchassis and no adjustment knobs on top, only holes for an Allen key, as well as a circular shaped armboard. The bearing shaft has a steel trust ball.
Several changes have been made to Stabi over the years. Stabi 1985 has no power supply, a round belt and a bearing shaft with a spiked bottom for a trust bearing. The lid has simple hinges. The motor pulley has two different diameters for speed selection (33 or 45 rpm). Some turntables have a lever for speed change to 45 rpm. A threaded clamp was an option.
Stabi with a power supply became an option.
Better hinges were introduced allowing the heavy lid to be left in an open position and allowing for lid removal.
Stabi was produced in three finishes – light and dark oak, and black.
A new bearing was introduced around 1995 with a shaft that had a flat bottom and the bearing held the shaft at five points. Although play could be felt, when the shaft was shaken, (see 2.10104.) when bearing is rotating there is zero play in the bearing.
In 1996 a flat belt replaced the round cross section belt. We do suggest that the round belt be replaced with a flat belt with appropriate modification (new motor and shaft with pulley for flat belt) as the turntable will perform better.
This turntable stayed in production until 2005.
When buying used products check turntable status. Check with us. The serial number is not always useful due to the possibility of upgrades being added at a later stage.
2.10102. Why is the bearing on my turntable slack when I move the shaft with the subplatter?
Older Stabi’s used a classic bearing with a sliding ring and a spiked shaft or ball. In 1995 we introduced a 5 point platter bearing. With this bearing the shaft was supported from the side at the top at two points, at the lower side with two points and a single point, eccentrically at the bottom of the flat shaft. This gives zero play in conditions where the platter mass and belt tension push the shaft in the motor direction. If the shaft is shaken, however, slack will normally be felt because the shaft is pushed away from the motor direction. If you try to push the shaft down and towards the motor you will feel no movement at all. See 2.10101.
2.10201. Should I remove spike protective cups for best results?
No need. In most cases you can keep protective cups on the spiked legs.
2.10401. How can I add a power supply to Stabi ?
This is simply a process of replacing the existing mains cable with a 5 pin DIN cable which is then plugged into the outboard power supply. If the turntable was supplied without PS for areas where the mains frequency is 60 Hz, then the use of the standard PS is not possible. This is because the diameter of the pulley is different for 50 Hz to the smaller one for 60 Hz. All our PS have output of 50 Hz, so the speed will be wrong.
There are, however, two options. Obtain a motor pulley with 50 Hz diameter, even if your mains is 60 Hz, or purchase a special version of PS which has 60 Hz output. This is the same PS which is also available for the Stabi S turntable.
To replace the cable on the motor, the platter, tonearm and subchassis must be removed in order to gain access below. Of course the turntable must be unplugged at the mains. Instructions how to connect wires are supplied with the PS.
2.10402. Can turntables be upgraded?
Each older Stabi (Stabi 2 in former YU) can be upgraded to current status though the cost may be high. Stabi 1 is not upgradeable.
2.10403. Can I upgrade from a round cross section belt to a flat belt?
Yes, but again there are a few options to be considered. In principle the motor pulley and the subplatter must also be replaced. To reach the motor the platter, tonearm and subchassis must be removed. This is done easily in the factory but is not so simple elsewhere.
The first stage is to check how the motor is mounted. On later turntables all motors were mounted on a black metal suspended plate by two screws. The first turntables, however, had plates with a smaller hole than the motor pulley and so the motor pulley was glued in position on the motor plate making it impossible to simply remove the motor. Very few of these pulleys were fixed with screws. There are two options. The motor pulley can be removed by heating and then the new motor pulley, for the flat belt, glued onto the motor or we can supply a new motor plate with a bigger hole for the motor pulley. This will then easily accept the new motor with a flat belt pulley. This metal plate is glued, or fixed by rubber and screws, onto the chassis.
The subplatter on the bearing shaft must also be replaced with a new subplatter for the flat belt. Here it is essential to find out which type of shaft and bearing is used. The older type of shaft has a pointed trust shaft and the newer has a flat trust point. You will need to obtain the same type of subplatter and shaft combination, if available or replace with the newer 5 point bearing. See also 2.10101.
In this case the Stabi turntable will be upgraded to the latest version of bearing and belt system.
2.10404. Can I still get various pre-cut armboards?
Yes. We still have various finishes and cut-outs in stock.
2.10501. Can I get hinges for the older Stabi turntables?
Yes.
2.20000. Stabi Ref turntable:
2.20101. Are different pre-cut armboards available for different tonearms?
Yes. We can even custom make a cut-out. This is not easy for the customer to do themselves due to the painted aluminium and acrylic construction.
2.20102. What maximum tonearm mass will the turntable accept?
Stabi Ref can accept tonearms with a mass of up to +2 kg. If more is needed, consult us.
2.20103. How many belts does Stabi Ref. use?
A single flat belt. There are a few early Stabi Ref. turntables from 1989 which have a set of two round belts with two extra passive pulleys below the platter.
2.20401. Is a dust cover available?
Yes and it covers the whole turntable unless fitted with the Air Line tonearm. We can supply a drawing so you can make one yourself from acrylic.
2.20501. Can I remove the Stabi Ref. suspension towers?
We do not recommend it! They are screwed and fixed exactly in position.
If you need to remove them, mark their position and in which corner they are. Also what is their position regarding clockwise rotation. They must be screwed back in exactly the same position. If you open the reservoir to reach the springs you MUST mark them and put them back in exactly the same position. Do not mix them up.
2.20502. Is hum on Stabi Ref. unavoidable?
No. If you have already tried grounding in the normal way, then add an additional ground wire from the nickel plated DIN connector at the rear of the turntable where the PS cable is connected, to the ground on the phono stage.
2.20503. What can I do if I have trouble levelling and adjusting suspension?
If you run out of the levelling adjustment range and you feel that one part of the subchassis is not moving, then you will need to re-set the suspension towers.
Remove the platter, secure the tonearm and one person should lift up the top subchassis. Looking underneath you will be able to see four nickel plated spikes which fitted into the suspension towers on the lower chassis. These should all protrude the same amount, preferably all at the level of the lower edge of the subchassis. If not rotate the spikes on their thread until they are. Then return the subchassis, belt and platter and start levelling slowly, by small rotation of the two diagonally opposed knobs followed by the other pair etc. …..
2.20504. Why can I hear noise below the platter?
Check that the height of the subchassis is not too low.
2.30000. Stabi S and SD turntables:
2.30101. Is it possible to mount different tonearms on the Stabi S turntable?
Yes. Circular brass armboards are available with pre-cuts for various tonearms such as SME, Graham, Ortofon, Linn, Rega, Triplanar ….
2.30102. Can I use Stabi S, which is 50 Hz, in an area with 60 Hz mains voltage and vice versa?
A turntable which is without a PS (outboard power supply), must be used only in the area for which it was constructed. Platter speed is controlled by the mains frequency.
If the area is changed, a new motor can be purchased with the appropriate pulley size for 50 or 60 Hz.
2.30103. How can I get 45 rpm speed?
Turntables without PS have an adaptor which fits onto the existing pulley and increases the diameter, and rotating speed, of the platter. To do this the platter must be lifted, the belt removed and the adaptor inserted.
A power supply can also be added which will have electronic speed change.
2.30104. From what is the chassis’ main T beam made?
This is machined from a solid brass rod, which gives a very rigid, inflexible and non-vibrating connection between the platter bearing and the tonearm support.
2.30201. How important is the distance of the motor tower from the T beam?
Not very. The tension of the belt will slightly affect accurate speed. If the motor is nearer the speed will be a fraction higher.
2.30202. What is the best support for Stabi S?
Either a strong, heavy and rigid stand or a light flexible one. It will also work well on a flexible floor if paired with a damped tonearm such as Stogi S.
If the turntable is sited on a thin glass shelf then a wooden platform should be put below the turntable.
2.30203. Where can I put the tonearm cable below the T beam?
In some situations where there is not much space, the T beam should be raised( also motor tower and the lid) or be used Stabi S wooden platform, which has a hole for the accommodation of the cable loop, should be used.
2.30301. How can I clean and protect the lacquered brass?
Use a soft cloth and a mild washing up solution. See 2.0303.
2.30401. Can Stabi S be upgraded to accept two tonearms?
Yes. The shorter part of the T beam can be replaced by the longer part called the Stabi SD kit. The existing lid cannot, however, be used.
2.30402. Can I add an electronic power supply?
Yes. A small modification is needed. The mains cable will have to be replaced, a few parts removed and the motor wires repositioned. This is a simple process. If Stabi S is made for a 60 Hz area, then a special version of the PS must be ordered with a 60 Hz output, or the motor pulley replaced with a pulley for 50 Hz.
2.30403. Can a 12 inch arm be fitted?
Yes, a special longer 12 inch beam ( Stabi S 12” kit ) must be ordered.
2.30404. Can I increase platter mass?
Yes, with the addition of another platter called “Platter S kit”. It is simply placed below the main platter and adds 3 kg. With the Platter S kit extra legs are also provided to give increased lid height.
2.30501. What can I do if the motor slides towards the T beam?
Remove dirt and dust from supporting legs and clean surfaces to increase friction.
2.30502. I can hear noise below the platter?
Check that the motor is not too far away and that the pulley is not touching the inner, lower part of the platter.
2.30503. Do the ‘O’ rings need replacing?
Over time, especially if exposed to sunlight, they might crack. ‘O’ rings are available as spare parts.
2.40000. Stabi XL turntables:
2.40101. How many tonearms can be positioned around this turntable?
Even with 4 motor towers, three tonearm towers can be located around the platter.
2.40102. Which tonearms can be mounted onto Stabi XL?
The standard turntable is supplied with one VTA tower. The top brass armboard plate is removable on this tower and pre-cut armboards can be supplied for most known tonearms (SME, Graham, Triplanar etc.). If not consult us.
2.40103. Which tonearms can be mounted on a Stabi XL which has a tonearm tower without VTA adjustment?
At present (2009) only Air Line, 4Point and Stogi Ref 313 VTA. But soon it will be available for other tonearms as well.
2.40104. What are the differences between Stabi XL, Stabi XL2 and Stabi XL4?
Stabi XL: has been produced since 1999.
Stabi XL2: In 2007 a new PS was added called PS XL2.
Stabi XL4: is the same as Stabi XL2, but with the addition of two extra motors.
Stabi XL: can be converted into Stabi XL2 by adding the new PS XL2 and into Stabi XL4 by adding two more motor towers.
2.40201. How important is the distance of the motor tower?
This is not so critical due to the use of AC synchronous motors. Details can be found in the manual and, with Stabi XL 4, a protractor is supplied.
2.40401. There is not enough space on the Stabi XL tower to connect a 5 PIN connector to SME or Graham arms?
With older towers this is a problem due to very limited space below. Initially it was designed for the SME flat connector but SME changed it to a 5 pin rotating DIN plug which required more space. See if moving the tonearm off centre of the tower provides a bit more space and move the tower to keep the same pivot to tonearm distance. Towers made from 2008 have much more space for connectors.
2.40501. How can I cure a hum problem?
Add an extra ground wire to the tonearm tower. Be sure to connect this to an unlacquered surface such as a screw on the brass armboard.
2.40502. What should I do if the platter needs manual help to start up?
Check the amount of oil. Run the platter for 24 hours and ensure that the motor towers are not too far away. Clean belts and pulley and see if all motors are working without the belts. Otherwise consult us. If the turntable is older, remove the old oil and replace it with Lubcon. See 2.0302. This oil improves only the start up.