Hi,
I'm back on this project. I put a sine wave through my EVM and measured the BTL on both sides of the speaker through a low pass filter. I am playing the tone through this 4 ohm speaker: https://products.owolff.com/acoustics/speakers/OWS-4065T-4C
I'm providing 5.5V for SPKVDD from an external power supply.
Here is a screenshot I took of my oscilloscope:
The sine wave is ~4.8Vpp and is beginning to clip. I can hear some distortion in the speaker. 4.8Vpp = 1.7Vrms, so the average power delivery into the 4 ohm speaker is 1.7Vrms^2/4 = 722.5mW. That's nowhere close to what the part claims it can do - 2.5W into 4 ohms. Do I have something wrong in my configuration? All I did was allow the default init script to run, then I changed the analog attenuation to 0.
I'm using the signal generator that is part of Soundcard Oscilloscope to generate a sine wave at 500Hz.
I turned the input signal up so the clipping is easier to see.
My ΔY is 5V. Shouldn't I be able to get a lot more out of this thing before clipping starts?
I experimented with the DRC but wasn't able to find a happy setting. The only way I can eliminate the clipping is to turn my Windows volume down, but then the audio level is too low for our application.