Frequency Loom

RTA, SPL-style levels, RT60, Field Setup, and offline reference signals for audio engineers and creators.

Frequency Loom is an audio measurement bench for engineers, musicians, venues, classrooms, studios, and room-tuning work.

It brings practical sound inspection tools into one focused iPhone and iPad app: spectrum analysis, level monitoring, tone generation, tuning, loudness, reverberation, room checks, and reference workflows for common audio problems.

Version 2.1 adds Field Setup, a measurement-readiness workflow that helps users document calibration, input path, quiet baseline, mounting, FFT size, and export plan before a session. It recommends a tool chain for studio tuning, live-venue checks, noise logs, and vocal range work, then creates a copyable session brief for notes or client reports.

It also adds an Offline Reference Pack with bundled 48 kHz WAV test signals: white noise, pink noise, brown noise, speech-band noise, low-end room noise, and a 20 Hz to 20 kHz log sweep. These signals help check playback paths, room behavior, rattles, spectrum response, and field setup without relying on connectivity.

Core tools:

• Real-time spectrum analyzer with octave-band views and NC overlay
• SPL-style level views with A, C, and Z weighting plus Slow, Fast, and Impulse response
• Field Setup readiness score with source links and measurement limits
• Scrolling spectrogram for seeing frequency over time
• Chromatic tuner with reference pitch controls
• LUFS loudness views for podcast, streaming, and broadcast checks
• RT60 reverberation workflow with multiband RT60
• Tone generator with sine, sweep, noise, and impulse modes
• Standing-wave heat-map workflow for low-frequency room issues
• Crossover, mains hum, speaker time-align, polarity, delay, and vocal warmup tools
• Noise-dose reference log with CSV export and in-app source notes
• Offline reference signals with built-in playback and usage notes

Frequency Loom is built with AVAudioEngine and Accelerate-based signal processing. Microphone measurement is live on device. The app does not require an account, does not upload audio, and contains no tracking SDK.

Absolute sound level and noise-dose readings depend on microphone calibration, input path, placement, and environment. Frequency Loom is a field reference tool, not a certified compliance meter or clinical hearing device.