I simulated biased and unbiased Sallen-Key high-pass filters and got different responce curves.
I will be grateful if someone could point out on my error with biasing.
The results with the single supply voltage depend on the output impedance of the power supply. The circuit you show feeds half of any hum and noise on the positive supply to the reference input of the opamp.
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Although responce curve of circuit you proposing is somehow different at very low frequencies (-110db vs -140db at 10Hz which does not make real difference), attenuation of noice is much more important!
The results with the single supply voltage depend on the output impedance of the power supply. The circuit you show feeds half of any hum and noise on the positive supply to the reference input of the opamp.
Do it liked this:
My mistake, only one voltage divider is needed to make the half-supply bias voltage. The filter capacitor for it must have a high enough value for it to be almost a short circuit at your lowest frequency.
Your biasing for the lowpass filter is correct.