Fidelix 0 SideForce Tone Arm

The design of the tone arm traditionally focused on reducing tracking errors. But more important than that was the time shake due to the fluctuations in side force. This led to a much bigger problem than the tracking error.

The tone arm developed by Fidelix is "0 SideForce" since the side force is 0. No cancellers are required because the arm moves horizontally even if the side force is to occur.

Without an offset angle, it is as if a loose bass is crawling on the ground. If you like bass, it won't work. Because there is no ambiguity, it is like a master tape or a well-made digital device.

Rigid stainless steel, adopting a branch structure by jewelry bearings

The main parts of the arm are stainless steel materials which are difficult to process and strong, called SUS304.
It supports the cartridge firmly, coupled with a clear branch structure and a MITCHAKU head shell. In front of the branch point, it has a clean structure, but the weight behind the branch point is floating on the orthodoc with rubber, eliminating the small resonance sound.

The basic structure is a one-point type by jewelry bearings, but to eliminate the flattening of the left and right, the record side is made heavy, and the base position 20mm is deliberately contacted. Strictly speaking, it is a two-point structure, but from that pressure ratio it can be called 1.01 points. Since it is a structure like this, there is a rattan of about 0.1 millimeters if you hold it by hand, but during the performance, there is a clear operation without ambiguity by 3 points combined with 2 points above and 1 point of stylus.

This equation operates 1.01 points as long as gravity is present, so no true rattling occurs. The front of the branch is a strong structure, but the weight of the back of the branch point is floating in the orthodoc with rubber, eliminating a small resonance sound.

The installation hole is φ30mm from the center of the turntable to 232mm, but it fits well with the 230mm Fidelity-Research FR-64 and 235mm SAEC WE-308. Tracking error 0 degree design with a record radius of 89.6 mm.

Since the arm position is 232mm ± 3mm, it also fits holes for FR-64 and WE-308N. For 230mm such as FR-64, the underhang is 16mm, and the record radius is 84.3mm. For 235mm such as WE-308N, the underhang becomes 21mm and the record radius is 97.1mm. The hole that can be drilled is 232 mm from the center of the turntable at φ30, but many short arms can be used if a long hole of 215 mm to 235 mm is drilled.

I read FIDELIX's 0 SideForce Arm article and it became interesting.
The following comments were particularly interesting.
"The secret of the sound of the pure straight arm is that there is no offset of the arm
It is more important that the cantilever of the cartridge is aligned on a straight line that connects the stylus to the arm point, and the sound quality is more important than the tracking error that the cantilever side is not able to swing due to changes in the resistance of the sound groove of the record. "
Really?
The Pure Straight Arm is disadvantageous to in-record distortion, but it seems to have some advantages to supplement it. In London cartridges that do not have cantilever, it will be ineffective pure straight arm, but what?
Now, if I thought that it would be good to make a new player body for the arm, I knew that it could be attached to my DP-900M, and I immediately introduced it.
FIDELIX specified value: mounting pitch 232 ± 3mm, hole diameter 30mm
DP-900M Actual measurement: mounting pitch 232mm, hole diameter 35mm
The hole diameter is 5mm large, but no problem.
The auto arm lifter "The Q UP" also works perfectly.
As a first impression, I am surprised by the crisp sound that wakes up. It's good to get out. If this is the sound of the correct arm, then all other arms are faulty, so much more direct feeling is different. *Audio common sense is insane