can I really choose any of those three combinations of capacitors and resistors and get the same result in regards to noise reduction, with varying levels of voltage drop?
Is there any disadvantage to using a 10uf cap and a 1K resistor, aside from a 10uf cap being a little expensive compared to a .1uf cap?
So if I don't want to attenuate anything below 16khz
* The attenuation is 6db per octave
Exactly what are you trying to achieve by having a filter?
There is no need to bother with a filter at the low end, it does nothing for you and only adds components and possible extra distortion.
In the single-ended input application, an input capacitor, CI, is required to allow the amplifier to bias the input signal to the proper dc level. In this case, CI and RI form a high-pass filter with the corner frequency defined in Equation 2. The value of CI is an important consideration. It directly affects the bass (low frequency) performance of the circuit.
That amplifier works by sending pulses to the speaker and uses the inductance of the speaker to work as the reconstruction filter. It is not a conventional amplifier.
There is another low-pass filter connected to the output of the DAC (R7 and C8). This is for filtering out the 'square wave' component you see in the recreated-audio wave. Even though the noise is only 1/4096'ths of the signal (about 1.2mV) its still noise and these two components filter out anything above 11KHz. The reason the filter cut-off frequency is 11KHz and not 22KHz is that if you sample at 22KHz you will only be able to reproduce frequencies at half that rate, 11KHz. This is the Nyquist theory. It is sneaky but true. If you try to sample 16KHz waveform at 22KHz it will actually sound much -lower-, it will play at 6KHz (it is 'mirrored' around 11KHz)
So wait, are you saying that this amplifier:http://www.ti.com/lit/ds/symlink/tpa6211a1.pdfIs not a conventional amplifier?
That filter is known as a reconstruction filter, it's job is to remove the noise introduced by the sampling process. If this is in the audio range this is needed to stop a whine. If it is outside the audio range it is not needed.That amplifier works by sending pulses to the speaker and uses the inductance of the speaker to work as the reconstruction filter. It is not a conventional amplifier.
Now that you know this is a class AB amplifier, would you amend this statement?
How do I know if the stair stepping from the samples might produce an audible whine?