Moving Air, 1St Acoustics Design Laboratory, Loudspeaker Designed & Engineered In Singapore

Electrical Test Parameters (12Vdc Supply):

Frequency Resp. at all pass mode (-6dB): 10Hz – 100kHz
Frequency Resp. at LPF mode (-3dB): 10Hz – 100Hz
Frequency Resp. at HPF mode (-3dB): 100Hz – 100kHz
Total Harmonic Distortion (10 to 100kHz @100mW into 4ohms): 0.1 – 0.4%
Total Harmonic Distortion (10 to 100kHz @1W into 4ohms): 0.1%
Rated RMS Output Power in Single Ended @10% THD into 2ohms: 4 x 75Wrms
Rated RMS Output Power in Bridge Mode @10% THD into 4ohms: 2 x 150Wrms
Signal to Noise Ratio @1W into 4ohms: 95dB

The right amount of power, and the right features, that's what marks the right power amp for your car audio system. Generally you should pick an amplifier that can deliver power equal to twice the loudspeaker's continuous IEC power rating. This means that a loudspeaker with a "nominal impedance" of 4 ohms and a continuous IEC power rating of 60 watts will require an amplifier that can produce 120 watts into an 4 ohm load.

A quality professional loudspeaker can handle transient peaks in excess of its rated power if the amplifier can deliver those peaks without distortion. Using an amplifier with some extra "headroom" will help assure that only clean, undistorted power gets to your loudspeakers. This additional headroom enable the amplifier to cleanly reproduce transient peaks that exceed the amplifier's rated power.

The TrueRMS UltraLinear Class AB Power Amplifier is designed with extra headroom which enables it to reproduce music signal that far exceed the amplifier's rated RMS power.

Another Important factor is the Slew rate of the amplifier. The term is used to define the maximum rate of change of an amplifier's output voltage with respect to its input voltage. The unit of measure is volts per microsecond. As far as slew rate having an effect on perceived sound, the real issue is slew rate limiting, which relates to an amplifier’s ability to pass complex waveforms without clipping them, resulting in an open musical sound. Slew rate is measured by feeding an input signal that is too fast for the amplifier to cope with. Therefore, the design of TrueRMS Class AB amplifier is designed with good transient and impulse response. We believe a good amplifier should sound fast and able to react with complex high speed signal input from the source.

Another important parameter is called the Damping factor and it is the ability of a power amplifier to control loudspeaker motion. It’s measured in Damping Factor, which is load impedance divided by amplifier output impedance. Let’s explain. If the speaker impedance is 8 ohms, and the amplifier output impedance is 0.01 ohms, the damping factor is 800. The lower the amplifier’s output impedance, the higher the damping factor, and the tighter the sound is. A damping factor of 1000 or greater is considered high. As you might suspect, damping factor is most important at low frequencies, say 10 Hz to 400 Hz. High damping factor equals tight bass.