Multi-Band Crossover Calculator

Linear distribution spaces the crossover points evenly in terms of frequency (e.g., 100 Hz, 200 Hz, 300 Hz), which can be useful for applications where equal frequency intervals are needed. Logarithmic distribution, on the other hand, spaces the points based on a logarithmic scale (e.g., 100 Hz, 1,000 Hz, 10,000 Hz), which better reflects how humans perceive pitch and is ideal for audio applications like mixing and mastering. Logarithmic spacing ensures more focus on lower frequencies, where most musical energy resides, while still covering higher frequencies effectively.

The optimal number of bands depends on the complexity of your mix and the specific goals of your processing. For instance, bass-heavy genres like EDM or hip-hop often benefit from a dedicated sub-band for precise low-end control, while simpler acoustic tracks may only need two or three bands. Over-splitting (e.g., using five bands unnecessarily) can lead to phasing issues and overly complicated processing. A good starting point is three bands: low, mid, and high, which can be adjusted based on the material.

While crossover points vary depending on the material, common starting points for a three-band setup are around 120 Hz for the low-to-mid transition and 2,000 Hz for the mid-to-high transition. For a four-band setup, additional points might include a sub-bass crossover at 60 Hz and an upper-mid crossover at 5,000 Hz. These values can be adjusted based on the genre, instrumentation, and desired tonal balance. Always use your ears to fine-tune these points to suit the mix.

Phase issues occur when the audio signal at the crossover points is not perfectly aligned, leading to cancellation or reinforcement that can alter the tonal balance. This is especially problematic with steep crossover slopes or poorly chosen crossover points. To minimize phase issues, use gentle slopes (e.g., 12-24 dB/oct) and test your processing in mono to identify anomalies. Some advanced plugins also offer linear-phase crossovers, which can eliminate phase distortion at the cost of added latency.

The minimum and maximum frequency values define the range within which the bands are distributed. For example, setting the minimum frequency to 20 Hz and the maximum to 20,000 Hz covers the full human hearing range, suitable for most music genres. However, narrowing this range (e.g., 50 Hz to 10,000 Hz) can focus the processing on the most relevant frequencies for certain styles or instruments, such as vocals or acoustic guitars. Always set these values based on the content of your mix.

One common mistake is over-splitting the frequency range, which can lead to unnecessary complexity and phasing issues. Another is setting crossover points too close together, which can cause overlapping and muddy sound. Additionally, failing to consider the distribution type (linear vs. logarithmic) can result in unnatural band spacing. Always start with a clear goal for your processing and test the results critically to ensure they enhance the mix rather than complicate it.

Multi-band crossovers allow you to isolate problem areas in the frequency spectrum for targeted processing. For example, if your mix has muddy lows, you can create a low band that isolates frequencies below 120 Hz and apply EQ or compression to clean them up. Similarly, if the highs are harsh, a high band above 8,000 Hz can be used to apply de-essing or gentle EQ cuts. By focusing on specific bands, you can address issues without affecting the rest of the mix.

Multi-band crossovers are used in a variety of production tasks, including multi-band compression, where each band is compressed independently to control dynamics more precisely. They are also essential in mastering, where different frequency ranges may require unique processing to achieve a balanced and polished sound. Additionally, multi-band crossovers are used in sound design to split frequencies for creative effects, such as isolating the low end for sub-bass enhancement or the high end for shimmer reverb.