Spectrum vs DecibelRTA

Spectrum turns your phone into a modern real-time audio analyzer - the clean, fast tool that older spectrum apps never gave you. See sound the moment it happens: a live FFT frequency spectrum and a scrolling spectrogram (waterfall), with automatic peak detection and the matching musical note. Built for a phone screen, with a beautiful dark and light theme - not a cramped desktop port. WHY SPECTRUM • Modern, readable interface - designed for touch, dark & light themes • Save your measurements and revisit them anytime (most analyzers forget everything the moment you close them) • Export the spectrogram as a high-resolution image, or your data as CSV • Works on both iPhone and iPad • Real peak frequency + musical note readout, in cents FEATURES • Real-time FFT spectrum, log or linear frequency axis • Spectrogram (waterfall) view • Tap the chart for a frequency cursor with dB and musical note • Peak hold and peak-frequency tracking • Musical note detection (A4 = 440 Hz) • A-weighting for perceived loudness • Adjustable FFT size (2048 / 4096 / 8192) • Save, name and organize measurements • Image & CSV export • 8 languages SPECTRUM PRO - one-time purchase, no subscription • 1/3 octave RTA view with per-band peak hold - the classic real-time analyzer used for live sound and room tuning • Tone generator: sine tones, 20 Hz-20 kHz logarithmic sweep, white & pink noise for testing speakers and room acoustics • Peak list: the strongest peaks with harmonics tagged • Up to 4 frequency markers on the chart • Calibration offset (±20 dB) to match a reference meter • Extra-high resolution 16384 FFT • High-resolution image export and no ads, forever Everything is processed on your device - no audio is ever uploaded. Microphone access is the only permission needed. Perfect for musicians, audio engineers, students, DIY speaker builders, hum & noise hunters, and anyone curious about the sounds around them.

DecibelRTA is an ultra-fast, professional real-time acoustic analyzer combining a fractional-octave IIR spectrum analyzer and an advanced IEC sound level meter on a unified display. Engineered with a native, zero-latency DSP core, DecibelRTA displays 11 vital acoustic metrics simultaneously without requiring navigation through menus: 11 METRICS AT A SINGLE GLANCE • Instant Spectral Pitch: Dominant musical note (e.g. A#2), frequency (Hz), and exact level (dB). • Core Metrology Chips: Leq 5s (equivalent continuous level), ACUM (psychoacoustic sharpness), LRA (Loudness Range dynamic spread), L50 (median ambient level), and CRST (crest factor). • Standard SPL Bar: SLOW (1s), FAST (125ms), and instant PEAK decay monitoring. HIGH-PRECISION SPECTRUM ANALYZER (RTA) • 3, 6, 12, and 24 bands per octave constant-Q filter bank (up to 240 selective IIR bands). • Contextual dual-path engine delivering sharp low-frequency transient tracking below 280 Hz. • Real-time spectral centroid, active -3 dB bandwidth marker, and continuous peak-hold curve. • Linear regression spectral tilt line (beta) for instantaneous noise color identification (pink, white, brown noise). • Built-in industry reference target curves (Flat, Audiofrog, Harman Room, JBL House, B&K Optimum) with a ±3 dB tolerance corridor. IEC 61672 SOUND LEVEL METER & STATISTICS • Type-standard A-weighting with true-RMS exponential ballistics (FAST / SLOW). • Continuous 5-second sliding Leq and sliding statistical histogram (L10, L50, L90). • Dual-mode dynamic range: Studio Mode (30 to 100 dB) and LIVE Mode (50 to 120 dB). • Fast overload CLIP warning and color-coded acoustic safety levels. BUILT FOR SOUND PROFESSIONALS • Live sound engineers & FOH: Quick feedback detection and stage SPL limits. • Studio & Mastering: Mix tonal balance, dynamic compression (LRA), and high-frequency fatigue check (ACUM). • Car Audio & Hi-Fi: In-cabin acoustic calibration and speaker alignment against target curves. • Acoustic & Industrial Hygiene: Noise floor surveys (L90) and OSHA/NIOSH threshold tracking. Microphone access is strictly processed on-device in real-time. No audio data is ever recorded, stored, or transmitted.