Kuzma Tonearm Tubes
Most Kuzma tonearms incorporate tubes machined from solid blocks of aluminium, though the internal construction is more complex than it looks. Conical tubes have less vibration than straight tubes. In addition the inside wall is not all the same thickness and, being made from two parts glued together, gives more damping and rigidity to the whole tube and the walls themselves.
Azimuth adjustment should be simple, easily repeatable and not adding any vibration or slack to the construction.
Kuzma uses counterweight eccentricity to set up azimuth in a unipivot bearing tonearms, but precise azimuth adjustment is made by repeatable shifting of a screw inside the counterweight.
The conical tubes contain a built-in worm drive, which allows precise tube rotation without any slack when the tube is rotating back and forth. The worm drive is immersed in damping grease. Locking the tube gives rigidity to the whole assembly.
The height of the tonearm can be adjusted in the armbase. Our best tonearms incorporate a VTA tower, which allows for repeatable VTA adjustments of O.Ql mm, during play, in the range of 10 mm with zero play, so it is not even necessary to lock the VTA mechanism.
Kuzma Detachable Headshell
The use of a standard detachable headshell for ease of cartridge replacement is always accompanied by mechanical and electrical compromise. Kuzma has, however, created their own unique hex shape, five point holding, fixing system, which holds the headshell in a precise and rigid position. This causes no structural weakness and is completely accurate. Electrical contacts are left intact as cartridge clips are unplugged from the cartridge.
Any breaks or solder joints in wires running from the cartridge to the phono input, are a compromise. Kuzma creates their own cables using thin wires obtained from reputable audio cable manufacturers. These wires run from the cartridge clips to phono plugs in one continuous length, inside the insulated and shielded tubes in a balanced configuration.
All parts are machined from solid aluminium or brass and are designed in such a way that, when assembled by screws or glue, structural rigidity is given to the tonearm. The effect on sound of even the smallest part is taken into consideration.
Unipivot is the simplest and yet very effective, very low friction, zero play type of bearing. Sliding and rolling surfaces inside the bearing cup are specially pressed to give the lowest starting friction, zero play and minimal vibration inside the cup or pivot point.
4Point bearings are constructed with two points in the vertical bearing and two points in the horizontal bearing, giving this tonearm a unique bearing configuration with lowest possible friction, zero play and stability of the tonearm in all directions, except those which need as much freedom as possible.
The ball bearings made by most worldwide manufacturers, while conforming to ABEC standards, are inadequate for our purposes due to dirt in grooves, on balls or in the bearing oil. We use the precise ball bearings which are used in gyroscopes. Each bearing is vacuum packed with its own serial number and we further individually test each bearing for noise and lubrication. Only then are they precisely mounted into tonearms, with zero play preloading.
Air bearings are bearings with the lowest possible friction and, if used as in precision machinery, they also have the highest rigidity in all directions. If an air bearing is used with low pressure, or has only a few holes which blow air out, then the tonearm will fioat. This will give low friction but any small force exerted on the cartridge during play, will cause tonearm instability and prevent the cartridge from accurately reading what is in the grooves.
We use a high air pressure porous graphite bearing which gives stable and precise positioning to an accuracy of below 0.001 mm. A force of even a few kg will not disturb the tonearm position.