ListenAid
MusicUtilities

ListenAid

Michael Reisigl · released 30 Jun 2025 · Open in App Store ↗

Revenue 30d not estimated
Downloads 30d not estimated
Rating 5.00 4 reviews

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RatingPrice
Austria100%45.00€4.99 $5.77
United Arab Emirates<1%0AED 14.99 $4.08
Afghanistan<1%0$3.99
Antigua And Barbuda<1%0$3.99
Anguilla<1%0$3.99
Albania<1%0$4.99
Armenia<1%0$4.99
Angola<1%0$3.99
Argentina<1%0$3.99
Australia<1%0A$5.99 $4.25

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Description

ListenAid - intuitive & clean realtime audio spectrum analysis.

ListenAid is an acoustic visualization tool optimized for live sound engineering and system tuning (leveraging transfer functions and multi-resolution processing), delivering maximum performance through Metal and Accelerate hardware acceleration.

Audio Engine & Core DSP

Lock-Free Processing (RingBuffer): non-blocking, zero-dropout audio.

Low-Level Math (vDSP): minimal CPU load

Real-Time Transfer Function: Live reference vs. live channel division: instantly shows frequency responses differences

5 different Analysis models:

STFT: Standard Short-Time Fourier Transform.

CWT: Continuous Wavelet Transform for high-frequency time resolution; optimized via integral images.

CQT: Constant-Q Transform with variable smoothing.

QTAM: Amplitude demodulation in the frequency domain.

Multi-Resolution: Concurrent Low, Mid, and High FFT windows for low-end frequency and high-end time resolution.

Metal GPU Rendering

Spectrogram is GPU-offloaded; maintains 60 FPS even at massive bin sizes

Phase Reassignment: Analyzes frame phase differences, shifts energy to exact sub-bin frequencies to sharpen visual traces

Simultaneous FFT Traces: Concurrently plots Live, Reference, and Secondary traces with customizable colors and opacities

Dynamic Viewport (ViewportMath): Continuous pan and zoom

Analytical Tools & Precision

Sub-Bin Peak Detection: Calculates precise peak frequencies using FFT phase correction or logarithmic-parabolic interpolation

Pitch Conversion (FrequencyConverter): translates frequency peaks to notes, showing cent deviations (with adjustable concert pitch)

Weighting & Tilt: A- and C-Weighting filters; adjustable display tilt

Smoothing & Averaging: Exponential, RMS, LUFS, Leq or Peak Hold averaging; psychoacoustic fractional octave smoothing (1/96 to 1 full octave).

System Tests & Signal Generation

Sine Generator: Artifact-free oscillator with amplitude fade envelopes; outputs up to the Nyquist frequency

Channel Control (SystemTestManager): Routes the generator or loop player via Normal, Solo L/R, or Phase Invert

Loop Playback: Imports and loops custom audio files to test spaces using known reference tracks

Workflow & Connectivity

Multipeer Control (MultipeerManager): fully remote-control another instance at the mixing desk (volume, mute, generator, playback)

Smart Routing: AudioEngine safely intercepts hardware changes and manages BT profiles

Preset System: Instantly save and recall all DSP and UI configurations via slots A, B, and Y.