GRS 4FR-8 Full-Range 4-1/2" Speaker Pioneer Type A11EC80-02F

The GRS 4FR-8 is a 4-1/2-inch full-range driver engineered to deliver clear, natural midrange and bass response in compact loudspeaker designs. As a broadband subwoofer, it excels in applications where space is limited but sound quality cannot be compromised, making it an ideal choice for small bookshelf speakers, soundbars, or custom audio projects that require a single driver to cover a wide frequency range. Its paper cone and ferrite magnet combination produces a balanced, warm sound profile that suits both music and dialogue reproduction.

Technically, this driver features a nominal impedance of 8 ohms with a DC resistance of 8.11 ohms, ensuring compatibility with standard amplifiers. The sensitivity is rated at 91 dB SPL at 1 metre with 2.83V input, offering efficient power handling. Key parameters include a total Q factor (Qts) of 0.82, with mechanical Q (Qms) at 5.14 and electrical Q (Qes) at 0.98, indicating a well-damped response suitable for sealed or ported enclosures. The voice coil inductance is 0.71 mH, and maximum linear excursion (Xmax) is 1 mm. The driver’s cut-out diameter is 101.9 mm, with four mounting holes and a depth of 68.8 mm, fitting neatly into compact baffles. The ferrite magnet and paper cone construction ensure reliable performance and natural tonality, making the 4FR-8 a versatile choice for high-fidelity audio builds.