The Pro-Ject 75g Counterweight (part number 001) is a genuine replacement counterweight for compatible Pro-Ject tonearms. Correct counterweight selection is essential to achieving accurate tracking force: a counterweight matched to the cartridge mass places the balance point closer to the tonearm bearing, allowing precise stylus force adjustment and reducing unwanted mechanical resonance.
What a Counterweight Does
The counterweight mounts at the rear stub of the tonearm, opposite the cartridge and stylus assembly. By threading the counterweight onto the stub and adjusting its position, you set the downward force that the stylus applies to the record groove. This vertical tracking force (VTF) is critical for faithful playback: too little force causes mistracking and distortion, while too much accelerates stylus and record wear. Each Pro-Ject tonearm counterweight carries a part code that identifies the correct mass and thread specification for a given tonearm family.
Compatibility
The 001 series counterweight weighs 75g and is suited to cartridges in the mid-weight range. Pro-Ject supplies a comprehensive series of replacement counterweights, each identified by a part number, to cover the wide variety of cartridges available. Selecting the correct weight for your cartridge ensures the counterweight sits at a mid-point on the tonearm stub rather than towards the extreme rear, which is the optimal position for balanced, precise tracking force adjustment.
Installation
The counterweight threads directly onto the rear stub of compatible Pro-Ject tonearms. Once fitted, balance the tonearm by rotating the counterweight until the arm floats level. Then use the tracking force scale engraved on the counterweight body, or a dedicated stylus force gauge, to dial in the precise downforce recommended by your cartridge manufacturer. Re-check anti-skating and cartridge alignment after any counterweight change.
Genuine Pro-Ject Part
This is an original Pro-Ject Audio Systems spare part. Using the correct manufacturer-specified counterweight maintains the tonearm-cartridge resonance frequency in the optimal range, contributing to low distortion, accurate channel separation, and extended stylus life.