Infinity Primus PS-8 (2003)
A compact powered subwoofer from Infinity's Primus series, with an 8-inch driver and 100 watts RMS output.
Overview
The Infinity Primus PS-8 is a powered subwoofer made in 2003 by Infinity Systems, Inc. It belongs to the Primus series. It has an 8-inch driver and a built-in amplifier rated at 100 watts RMS. Frequency response is 35 Hz to 150 Hz (±3dB), which suits smaller to mid-sized rooms. Inputs are line-level, high-level and LFE. There is also a phase switch, and the rear panel carries the level and crossover frequency controls.
Specifications
| Power Output | 100 watts RMS |
| Frequency Response | 35 Hz – 150 Hz (±3dB) |
| Crossover Frequency | 150 Hz |
| Driver Size | 8 inches |
| Dimensions (WHD) | 270 x 445 x 426 mm (10.6 x 17.5 x 16.8 in) |
| Weight | 15 kg (33 lb) |
Design
The Primus PS-8 is a self-contained powered subwoofer in a compact cabinet with clean, unobtrusive styling. The amplifier is plate-mounted. It takes both line-level and high-level inputs, so it connects to receivers and amplifiers either way.
Market
Used units have sold for €100 in the Netherlands (Hifishark, Feb 2026) and $180 AUD on Australian forums (Stereonet, 2019). Some owners report a humming noise as a possible problem. Otherwise it has a quiet reputation among vintage audio enthusiasts for solid performance.
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