# Air Band Enhancer

Brighten dull vocals or masters with a high air shelf plus an exciter that synthesizes new top-end harmonics — the Aphex Aural Exciter architecture built from FFmpeg.

> Canonical page: https://elysiatools.com/en/tools/audio-air-band-enhancer

- **Category:** Media

- **Keywords:** air band, exciter, aural exciter, high shelf, brightness, top end, sheen, sparkle, vocal air, mastering eq

## Overview

Two complementary brightness tools in one render. The air shelf is the classic mastering move: a wide high shelf (8/10/12/15 kHz corners, up to +9 dB — the same corner positions as the Mäag EQ4 Air Band selector) that lifts what is already there. The exciter is what a shelf cannot do: following the original 1979 Aphex Aural Exciter block diagram, everything below a tuneable 1.5–4 kHz corner is removed with a 2nd-order Butterworth high-pass, the remainder is pushed 9 dB into an asymmetric biased-tanh soft clipper (val(x) expressions evaluated per channel), so the surviving tones sprout new octave and fifth harmonics an octave or more above the original content, and the distorted band is re-blended with the dry signal at a low mix level (0–60%) exactly like the Aphex Mix control. Because the harmonics ride on the music’s own high-frequency energy, the effect stays level-balanced instead of just getting louder — a limiter guards the summed output anyway. Before and after the render the tool measures the air band energy around the shelf corner and the harmonic growth in the 8.5–11.5 kHz zone with an FFT probe and reports both deltas, so you can see the shelf lift and the synthesized harmonics separately. If there is essentially no content above the exciter tune point (below −75 dBFS), the input is rejected instead of producing hiss-shaped nothing.

## Inputs

- **Audio file** (file)
- **Air frequency** (select)
- **Shelf boost (dB)** (number)
- **Exciter tune** (select)
- **Exciter mix (%)** (number)
- **Output format** (select)

## When to use

- Dull vocal tracks or dark instrument recordings lack presence and cannot be revived with standard EQ alone.
- Mastering or finalizing a mix that needs subtle high-frequency air, openness, and sheen across the top end.
- Restoring perceived high-end brilliance to band-limited, vintage, or heavily filtered audio stems.

## How it works

- The input audio passes through a selectable high-shelf filter at 8, 10, 12, or 15 kHz with up to +9 dB of clean boost.
- A parallel exciter branch applies a 2nd-order Butterworth high-pass filter tuned between 1.5 kHz and 4 kHz, then drives the high-passed signal into an asymmetric tanh soft clipper to synthesize musical octave and fifth harmonics.
- The synthesized harmonic content is blended with the dry signal at your chosen mix percentage (0–60%) and summed under an output limiter to prevent clipping.
- Before and after FFT probes measure and report the exact air-band energy boost and harmonic generation in decibels.

## Use cases

- Brightening lead vocals with a 12 kHz air shelf and subtle 2 kHz harmonic excitation for modern pop sheen.
- Polishing pre-master stereo mixes by lifting ultra-high frequencies above 15 kHz with clean linear shelving.
- Synthesizing high-frequency harmonics for acoustic guitars or drum overheads recorded with dark dynamic microphones.

## Frequently asked questions

### What is the difference between the air shelf and the exciter?

The air shelf amplifies high frequencies already present in the audio, while the exciter synthesizes brand-new upper harmonics from upper-midrange content.

### Can I use only the high-shelf EQ without the harmonic exciter?

Yes. Set the exciter mix percentage to 0% to apply only the high-shelf EQ boost.

### Why was my audio file rejected during processing?

If high-frequency content above the selected exciter tuning frequency is below −75 dBFS, the tool rejects the input to avoid amplifying pure noise or hiss.

### Which audio export formats are supported?

You can export the enhanced audio to MP3, WAV, FLAC, M4A, or OGG Vorbis formats.

### Does this tool increase the peak volume of my track?

The harmonic exciter blends at low relative levels and an output peak limiter guards the summed result to prevent digital overs.

## Related tools

- [Audio Add Silence](https://elysiatools.com/en/tools/audio-add-silence): Add a specified duration of silence to the start or end of an audio file
- [Backing Vocal Width Expander](https://elysiatools.com/en/tools/audio-backing-vocal-width): Turn a single vocal into a wide stereo harmony stack of 3, 5, or 7 transposed voices panned across the field.
- [Extract Center Channel](https://elysiatools.com/en/tools/audio-center-channel-extract): Extract the center channel from a surround audio file or video audio track
- [Audio Declipper](https://elysiatools.com/en/tools/audio-declip): Repair clipped audio by reconstructing peaks that exceeded the maximum amplitude. Restore distorted audio from overdriven recordings or excessive gain
- [Audio Filler Word Removal Map](https://elysiatools.com/en/tools/audio-filler-word-removal-map): Combine a timestamped transcript with the audio to mark filler words (um, uh, 嗯, 那个…) and optionally mute or remove them.
- [Karaoke Vocal Reducer](https://elysiatools.com/en/tools/audio-karaoke-track): Attempt to remove vocals from a stereo track
- [Audio Master Reference Match](https://elysiatools.com/en/tools/audio-master-reference-match): Match your mix's tonal balance and loudness to a reference track and export the corrected master, with a before/after third-octave band report.
- [Audio Remove Silence End](https://elysiatools.com/en/tools/audio-remove-silence-end): Remove silence from the end of an audio file

## Samples

- [Copyright-Free FLAC Audio Samples](https://elysiatools.com/en/samples/flac-samples): Lossless FLAC audio samples for testing and development, mirrored from MP3 set with nature sounds and meditation music
- [Copyright-Free MP3 Audio Samples](https://elysiatools.com/en/samples/mp3-samples): Collection of royalty-free audio samples for testing and development purposes including nature sounds, meditation music, and ambient audio
- [Copyright-Free WAV Audio Samples](https://elysiatools.com/en/samples/wav-samples): Uncompressed PCM WAV audio samples for testing and development, mirrored from MP3 set with nature sounds and meditation music
- [Copyright-Free Raw PCM Audio Samples](https://elysiatools.com/en/samples/pcm-samples): Raw PCM s16le audio samples featuring nature ambience and relaxing music for waveform, playback, and conversion workflows