Shadders
pfm Member
Hi,you don’t listen to the rectangular waveform as it is well past the human hearing range, you listen to a waveform reconstructed from the filtered pulse width modulated waveform which is in the audio band.
The output at the amplifier terminals is a filtered rectangular wave.
There is no reconstruction, as the filter is a continuous function with a rectangular wave applied. The output of the filter is just predominantly the lower frequencies in the rectangular waveform. So you are listening to a rectangular waveform, it is just that the high frequency components that make up the rectangular wave are attenuated.
Here is an example from Audio Science Review :
https://www.audiosciencereview.com/...easurements-of-nord-one-nc500-amp.7704/page-3
The screen shot of the amplifier is from a Teac amplifier using the Hypex module.
I am not disputing a subjective review, but the filter output is still a noisy signal. What i think this shows us is that the ears are not as good as we believe them to be.
Regards,
Shadders.