• 🎛️ Notch Filter Calculator

    Calculate the center frequency and approximate frequency range affected by a notch filter based on frequency and Q or bandwidth.

    Filter Settings
    Notch Center Frequency
    1,000 Hz
    Narrow notch filter
    Q Factor 10
    Bandwidth 100 Hz
    Approx. Lower Frequency 950 Hz
    Approx. Upper Frequency 1,050 Hz
    Center Frequency 0 Hz
    Q Factor 0
    Bandwidth 0 Hz
    Cut Depth 0 dB
    💡 Tip: Notch filters are useful when you need to remove a very specific frequency without significantly affecting the surrounding frequencies. They can be helpful for reducing hum, ringing, feedback, or other narrow-frequency problems.
    This calculator uses the standard relationship Q = center frequency ÷ bandwidth. The displayed lower and upper frequencies are an approximation based on a symmetrical bandwidth around the center frequency. Actual filter shapes vary between EQs and plugins.

  • A Notch Filter Calculator can help musicians, producers, recording engineers, and home-studio users determine the relationship between a notch filter's center frequency, Q factor, and bandwidth. Notch filters are designed to remove or significantly reduce a narrow range of frequencies while leaving much of the surrounding audio relatively unaffected.

    One common use for a notch filter is removing unwanted resonances. For example, if a recording has a particularly strong ringing frequency, a narrow notch can reduce that frequency without requiring a large cut across the entire frequency range.

    Notch filters can also be useful for dealing with electrical hum, feedback, room resonances, ringing, and problematic frequencies. The center frequency determines where the cut occurs, while the Q factor determines how narrow or broad the filter is.

    A higher Q creates a narrower filter, which can be useful when you're trying to target one very specific frequency. A lower Q creates a wider filter and affects a larger area around the center frequency.

    The basic relationship is Q = center frequency ÷ bandwidth. For example, a 1,000 Hz notch with a Q of 10 has an approximate bandwidth of 100 Hz.

    Tip: Use the narrowest filter that solves the problem rather than automatically making a deep, extremely narrow cut. If you're constantly using multiple aggressive notch filters, the underlying problem may be better addressed through microphone placement, room treatment, arrangement, recording technique, or another part of the signal chain.

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