GM Series

GM8-65F

P-Audio GM8-65F 8" 250W Low Frequency Driver

Click here to download the Datasheet (PDF)


The P. Audio ‘Golden Master’ GM8-65F is the intersection of advanced design and state of the art manufacturing. The GM8-65F is an 8 inch (203mm) mid/low transducer for high performance professional audio. The 2.5 inch (63.7mm) voice coil is designed for superior reliability and excursion, featuring low weight, high temperature rectangular aluminium wire and extended winding length. The weight-optimized ferrite magnetics maximize the coil’s strengths by providing strong magnetic flux across its whole range of movement. This keeps coil motion faithful to the audio signal without distorting. Aluminium ‘demodulation’ rings negate inductance effects in the motor, further improving the fidelity of coil movement. The ferrite magnet structure cooperates with a carefully optimized venting system on the bottom of the sleek Golden Master chassis to control airflow around the voice coil. This cools the durable design to further levels of reliability without losing sensitivity – the GM8-65F is rated at 1000 W peak power handling/250 W AES continuous power handling with nominal sensitivity of 95 dB. Linear and symmetrical stiffness behavior of the suspension compliments linear coil motion. The GM8-65F’s spider features roll geometry designed to provide symmetrical displacement, even at high power levels. The cone features a proprietary double-roll cloth surround. The perfect match of material and geometry mean ultra-low distortion of cone movement and ultra-low distortion of sound. Custom cone pulp provides light waterproofing, while low moving mass has been optimized for high performance 8” two-way designs. The ideal application for the GM8-65F is in very high performance sound reinforcement and large format public address systems. It is ideal for use in a well-tuned vented enclosure in a range of configurations – general purpose sound reinforcement systems, mid/mid-bass applications and floor monitors. The high efficiency rating allows the GM8-65F to be used as the low frequency section of small/medium format line array designs where a subwoofer is also used. Performance is optimized when using a high pass 4th order Butterworth filter tuned near the enclosure vent frequency. The GM8-65F offers an 85-3500Hz useable bandwidth, though the actual crossover frequency will be determined by the driver and horn combination in the user’s system.	General Specifications Nominal diameter............................................... 203 mm/8 in Power rating..........................................................250 W(AES) Nominal impedance............................................................ 8 Sensitivity........................................................................ 95 dB Frequency range.....................................................85-3500 Hz Chassis type.....................................................Cast Aluminium Magnet type...................................................................Ferrite Magnet weight...............................................1.41 kg/49.7 oz Voice coil diameter.......................................... 63.7 mm/2.5 in Coil material......................... Edge Wound Aluminium Wire Former material.......................................................Kapton Cone material.................................................................Paper Surround material............................................................Cloth Suspension............................ Single X-max.............................................................2 mm/0.08 in Gap depth.......................................................8 mm/0.31 in Voice coil winding width................................. 12 mm/0.47 in Net Weight......................................................... 4.3 kg/9.5 lb Packing Dimension WxDxH (mm)210mm x 210mm x 120mm Shipping Weight................................................ 5 kg/11 lb Small Signal Parameters Re.................................................................................... 5.1 Fs................................................................................... 88 Hz Mms.................................................................. 21.68 g/0.77 oz Mmd.................................................................. 19.71 g/0.70 oz Qms.................................................................................... 5.27 Qes................................................................................... 0.46 Qts.................................................................................... 0.42 Vas................................................................... 10.83 lt/0.38 ft3 SD............................................................................227 cm2 BI.............................................................................. 11.57 Tm Cms......................................................................1.5e-04 m/N Rms......................................................................... 2.3 Ns/m Le (at 1kHz)................................................................0.36 mH

The P. Audio ‘Golden Master’ GM8-65F is the intersection of advanced design and state of the art manufacturing. The GM8-65F is an 8 inch (203mm) mid/low transducer for high performance professional audio. The 2.5 inch (63.7mm) voice coil is designed for superior reliability and excursion, featuring low weight, high temperature rectangular aluminium wire and extended winding length. The weight-optimized ferrite magnetics maximize the coil’s strengths by providing strong magnetic flux across its whole range of movement. This keeps coil motion faithful to the audio signal without distorting. Aluminium ‘demodulation’ rings negate inductance effects in the motor, further improving the fidelity of coil movement.

The ferrite magnet structure cooperates with a carefully optimized venting system on the bottom of the sleek Golden Master chassis to control airflow around the voice coil. This cools the durable design to further levels of reliability without losing sensitivity – the GM8-65F is rated at 1000 W peak power handling/250 W AES continuous power handling with nominal sensitivity of 95 dB.

Linear and symmetrical stiffness behavior of the suspension compliments linear coil motion. The GM8-65F’s spider features roll geometry designed to provide symmetrical displacement, even at high power levels. The cone features a proprietary double-roll cloth surround. The perfect match of material and geometry mean ultra-low distortion of cone movement and ultra-low distortion of sound. Custom cone pulp provides light waterproofing, while low moving mass has been optimized for high performance 8” two-way designs.

The ideal application for the GM8-65F is in very high performance sound reinforcement and large format public address systems. It is ideal for use in a well-tuned vented enclosure in a range of configurations – general purpose sound reinforcement systems, mid/mid-bass applications and floor monitors. The high efficiency rating allows the GM8-65F to be used as the low frequency section of small/medium format line array designs where a subwoofer is also used. Performance is optimized when using a high pass 4th order Butterworth filter tuned near the enclosure vent frequency. The GM8-65F offers an 85-3500Hz useable bandwidth, though the actual crossover frequency will be determined by the driver and horn combination in the user’s system.

General Specifications

Nominal diameter............................................... 203 mm/8 in
Power rating..........................................................250 W(AES)
Nominal impedance............................................................ 8
Sensitivity........................................................................ 95 dB
Frequency range.....................................................85-3500 Hz
Chassis type.....................................................Cast Aluminium
Magnet type...................................................................Ferrite
Magnet weight...............................................1.41 kg/49.7 oz
Voice coil diameter.......................................... 63.7 mm/2.5 in
Coil material......................... Edge Wound Aluminium Wire
Former material.......................................................Kapton
Cone material.................................................................Paper
Surround material............................................................Cloth
Suspension............................ Single
X-max.............................................................2 mm/0.08 in
Gap depth.......................................................8 mm/0.31 in
Voice coil winding width................................. 12 mm/0.47 in
Net Weight......................................................... 4.3 kg/9.5 lb
Packing Dimension WxDxH (mm)210mm x 210mm x 120mm
Shipping Weight................................................ 5 kg/11 lb

Small Signal Parameters

Re.................................................................................... 5.1
Fs................................................................................... 88 Hz
Mms.................................................................. 21.68 g/0.77 oz
Mmd.................................................................. 19.71 g/0.70 oz
Qms.................................................................................... 5.27
Qes................................................................................... 0.46
Qts.................................................................................... 0.42
Vas................................................................... 10.83 lt/0.38 ft3
SD............................................................................227 cm2
BI.............................................................................. 11.57 Tm
Cms......................................................................1.5e-04 m/N
Rms......................................................................... 2.3 Ns/m
Le (at 1kHz)................................................................0.36 mH