The Mueta® solution
 

Honest, pure and clean sound

The MUETA® class D amplifier redefines the standard for high-end audio. In contrast to non-MUETA® class D amplifiers, the MUETA® solution involves a patented measurement method that guarantees the correct voltage at the speaker terminals under all conditions. The output voltage is totally insensitive to the actual load, irrespective of the type of speaker used. The results are no audible distortion, a flat linear response, and sound as pure as you can get.

Controlling the signal at the output

Output control techniques used in non-MUETA® class D amplifiers overlook the combination of the low-pass output filter in the amplifier and the crossover filter in the speaker, leading to an unwanted de-tuning of the crossover filter. Since MUETA® controls the final signal at the output behind the low-pass filter, whatever load is connected will not influence the output signal or change the speaker’s crossover filter performance.

Close to a perfect voltage source

MUETA® measures both current and voltage behind the analog low-pass filter. The current through the capacitor in the output low-pass filter is measured, which is an effective way of looking at the trend/slope of the output voltage (since current leads voltage by 90° in a capacitor). Via this form of feedback, MUETA® tackles problems before they happen, thus realizing a close to perfect voltage source. Together with the unique PWM modulator topology, MUETA® prevents deviation in the output voltage, thus eliminating any effects of supply variation, dead-time, output filter non-linearity, load dependencies, and so on.

Lower cost power supply

Due to the unique PWM modulation method used for MUETA®, the power supply rejection is very high. This means the signal is virtually independent of voltage ripple or supply drop due to high load, allowing a lower cost, simpler power supply circuit to be used without compromising performance.