Hello
I accidentally mechanically damaged output filter capacitor C38 on Amp100. Board still can be saved however I am not sure about the capacitance. Is it 100nF foil capacitor?
Thank you
Have a nice day
Hello
I accidentally mechanically damaged output filter capacitor C38 on Amp100. Board still can be saved however I am not sure about the capacitance. Is it 100nF foil capacitor?
Thank you
Have a nice day
It's a 470nF foild capacitor.
Thank you for your response. This setting leads to quite low cutoff frequency at 23kHz - I am interested why is it set so low?
Low? 23kHz is way outside the audible frequency range. It will be quite hard to find a speaker that can handle that frequency range.
It is a cutoff frequency. There is already -3dB at 23kHz. That is why I got surprised. So far what I have seen class D amps had it around 50kHz.
Sure there is a speaker that handle far more than 23kHz however I am not sure about human’s ears at that frequency.
If you're not very young, it will be hard for you to hear anything above 16kHz
That does not answer for my question. What makes it better with lower cutoff so you chose this design?
I did some calculations here: http://sim.okawa-denshi.jp/en/RLCtool.php using:
R=4 L=100u and C=470n and it seems overdamped, at 10kHz there is already -4,9dB. There is also significant phase shift starting at a few kHz.
However with L=10u and C=1u it seems much more standard. Have a look at screenshots.