Work out high pass filter cutoff instantly with clear inputs, formula shown and shareable results.
An RC high-pass filter uses the same cutoff formula, 1/(2 pi RC), but passes frequencies above it and blocks DC. Below cutoff the response falls at 6 dB per octave and phase leads, approaching 90 degrees far below cutoff.
RC high pass
fc = 1 / (2 pi R C); gain = 1 / sqrt(1 + (fc/f)^2)
Electrical results are planning estimates only. Verify against the applicable wiring rules (IEC 60364, BS 7671, NEC or local code) and have all installation work designed and checked by a qualified electrician.
It blocks DC bias while passing the signal, letting successive amplifier stages have independent operating points.
Well below the lowest wanted frequency — typically 10-20 Hz for full-range audio — because phase shift extends more than a decade above cutoff.