Once Calibration Disc
There are several issues that can affect turntable performance. The most common reasons for not obtaining optimal sound reproduction are:-
Cartridge alignment and speed accuracy have a critical effect on the coveted perfect sound quality that audiophiles strive to achieve. The "Once" Calibration Disc addresses these two signicant factors and, because it is a precision measuring tool, the listener's absolute satisfaction is ensured.
- incorrect playing weight (either too light or too heavy)
- vertical tracking alignment (VTA)
- misaligned cartridge
- mismatched bias setting
- inaccurate platter speed
High Technology Stuff:
The "Once" Calibration Disc is printed on Yupo Phase 3 - a totally synthetic three-ply material. It is made from an amazing polypropylene film that exhibits the following characteristics:-
The outstanding properties of Yupo Phase 3 ensure that the "Once" Calibration Disc will always remain a perfect circle with the spindle hole precisely in the centre.
- virtually untearable
- not affected by climate changes - will not shrink or expand
- impervious to moisture
- high resistance to creasing
Easy To Use Instructions - Cartridge Alignment
Turntable Speed Check
- Fit your cartridge to the headshell, without fully tightening the mounting screws (to allow for movement).
- Place the "Once" Calibration Disc on the centre spindle
- Perform the overhang measurement and adjust if necessary
- Carefully rotate the cartridge so that it sits parallel with the alignment gauge lines.
- Do this by viewing from the front and also checking the azimuth by viewing from above
- Repeat steps 3 & 4 to establish a precise alignment
- Tighten the cartridge mounting screws
- Periodically re-check the alignment
Note: To achieve the most accurate results, the turntable speed should be checked or adjusted while the stylus is in contact with a playing record.
- Place the "Once" Calibration Disc on the centre spindle (see note)
- Start the turntable on the desired speed and allow sufficient time for the motor and bearings to warm up
- Direct a suitable 50Hz/60Hz mains powered fluorescent light source onto the surface of the stroboscope
- The stroboscope ring associated with your speed setting and mains frequency should now appear stationary