I don't own Stabi M (I own XL4) but have heard it many, many times at Franc's place. This is a great turntable. You can't go wrong with it. With the 4point and Benz LP-S, it' a magical combination - extremely revealing and direct yet so musical. One day we compared it to the Studer A80 and guess what. The diference was NOT that great! In fact, on some material we even prefered the LP...
One of my customers who purchased an XL4 along with an Air Line and a 4Point seems intrigued with the Stabi M and could wind up using either the 4Point on it or perhaps purchasing another 4Point. Yes, the Stabi M is a beast, a very refined one at that.
This is not a turntable. This is a transcription machine. Kuzma Stabi M reads the DNA of the vinyl and tells you what was really going on in the control room. At least it seems so. Franc Kuzma is either a genius or has a lot of luck. It took him a long time, but this must be his legacy.
The structure is suspended, but extremely inert and heavy. And it has a dc motor.
The outer frame and sub-chassis is assembled from the factory.
The outer frame has three feet and the two in fron are adjustable, to make also the outer frame in level.
There are four decoupling towers in the outer frame, of which three are positioned above the feet. The sub-chassis is assembled on these towers.
Detailed levelling is made on the four knobs on the upper surface of the sub-chassis (like for Stabi Ref).
The decoupling is heavy and inert, but should be classified as suspended. I need to press with both hands to even see it move.
When the protecting knob is removed, I see the shaft for inverted bearing with the ruby ball in a cup
8-10 drops of bearing oil on the ruby tip and the rest on the shaft. Excessive oil drains to the reservoir (scrotum) in the bottom. So, no risk for overdose;
I remember some teacher saying diamond was the only thing that could etch ruby, and I'm not going to put my diamonds in that cup.
The structure with the sub-platter is similar to Stabi Ref, but the design is slightly altered from a conical interface to a cylindrical.
The only advantage with that (I can think of) is that it's easier to get closer tolerances with cylindrical surfaces.
The flat rim is very stiff, but no problem to assemble over the motor wheel and sub-platter;
The armboard is grotesque. Very plain but 40mm thick massive aluminum.
The hole for the armboard in the sub-chassis is quite big to accomodate for various arm types, but I would not recommend to drill at home. Even if most arms are fitted with protractor, you dont want a gap in the hole and certainly not a non-vertical drilling.
Kuzma has all possible armboard types, and this one is Linn based but with the 40mm hole ("Kuzma style").
There's a slit in the armboard for the tonearm cables. The weight of the cables does not affect the tonearm as the connection box is fastened to the vta tower.
When 4Point is moved/transported, the connection box shall be moved to other tap on the tonearm housing, avoiding stress on the thin tonearm cables.
4Point is idiot safe to assemble with the protractor. Nothing to read off or measure, just hang the protractor on the center pin and turn the tonarm housing until it rests in the hook in the other end.
4Point is mounted as a 9" arm in the armboard, since the vta tower is based on that.
The geometric dimension, however, is 11" since the tonearm assembly center is located at 11" in plane.
BUT, in play, the arm is 12" since the lateral bearings are located behind the tonearm center.
Here is a close-up of the bearings when I lift the housing to make them visible.
As the arm is mounted, it's time to connect the motor control.
The motor control generates a sinewave to a 3-phase frequency controlled dc motor by an advanced circuit.
I never cared too much about speed, and I think it's not so sensitive as to +/- some %. A constant speed however, that's important.
There's a 7-pole contact for the motor, and a 5-pole contact for the front panel control switches.
Motor control with start/stop, speed 33/45 and adjustment and storing of preferred speeds;
The front panel has the same functions for start/stop and 33/45;