Spektral

Spektral is a professional real-time audio analyser for sound engineers: identify feedback, measure system response, characterise room acoustics and monitor noise compliance.

FIVE ANALYSIS MODES

• RTA: live spectrum on a logarithmic 20Hz to 20kHz scale, above a scrolling time-frequency spectrograph with adjustable range and history

• Transfer Function: dual-channel H1 estimator with magnitude, phase, coherence, impulse response and Auto-EQ

• SPL Monitor: environmental noise compliance with Leq tracking and professional PDF export

• RT60: reverberation across octave bands (125Hz to 4kHz): T20, T30, EDT and R², via interrupted pink noise or an impulse

• STIPA: Speech Transmission Index to IEC 60268-16 with per-band MTF and SNR, a built-in test signal and a Bad to Excellent rating

RINGING OUT

• Ring-Out watches for feedback as you push the system and names the frequency the moment it starts to grow, not once it howls

• Every confirmed ring lands in a session list with a suggested notch and Q, ready to copy to the console

• Steady tones and hum can't trigger it: a frequency must be growing to be called

• Identify labels the most prominent peaks on demand, from the single strongest to the top six

PRECISION TOOLS

• Selectable FFT size from 2,048 to 16,384 points

• Cursor with parabolic interpolation for sub-bin accuracy, with musical note readout

• Peak hold with smooth decay, and snapshot compare to overlay a frozen trace for A/B

• Smoothing from 1/1 to 1/24 octave; frame averaging up to 32, plus infinite

• Zoomable axes, floating mic/reference meter and per-channel input meters

• Pink noise generator with adjustable output level

SPL MONITORING & COMPLIANCE

• A-, C- and Z-weighting, and Slow, Fast and Impulse time weighting, to IEC 61672 methodology

• Calibrate via reference meter or acoustic calibrator, remembered per device and per input channel, and it survives an interface moving port

• Gain tracking: change preamp gain mid-show and the calibration follows, so readings stay true without recalibrating

• Rolling Leq windows: 1, 5, 10, 15, 30 and 60 minutes, plus 8-hour

• Limit Guard: set a limit and see the window level, the zone, and how long before you reach it

• Session statistics with time-history graph, and PDF reports carrying metadata, equipment and calibration detail

TRANSFER FUNCTION & MULTI-POSITION CAPTURE

• Works with a two-channel interface, or with just your Mac and a mic using built-in pink noise as the reference: no loopback, no interface

• Impulse response (linear and ETC) with automatic reflection detection: arrival time, distance and level

• Comb-filter prediction overlaid on the magnitude trace

• Delay alignment: FFT-based detection, a guided wizard and manual sub-sample tuning

• Phase shown against the delay you locked, compensated to sub-sample precision, so it compares position to position and tool to tool

• Multi-position capture with quality scoring, weighted averages and per-capture PDF pages

• Auto-EQ: up to 6 parametric suggestions with smart gain limiting

REMOTE MONITORING (add-on)

• Deploy iPhones as wireless SPL monitoring stations at multiple points

• Live Mac dashboard showing SPL, Leq and peak for every site, with a satellite map and heat propagation overlay

• PDF compliance reports with a page per remote location

• iCloud sync: no servers, no accounts, no configuration. One-time purchase, all your devices

DESIGNED FOR PROFESSIONALS

• Dark interface for low-light environments, with single-key shortcuts for the controls you reach for mid-show

• Smooth, low-CPU rendering that stays responsive through a long session

• Works with any Core Audio input device. Native SwiftUI, launches instantly

Monitor off-site noise propagation at live events, track occupational exposure in studios, characterise room acoustics and verify speech intelligibility. The workflow professional acousticians use, in a native Mac app.

Spektral is not a certified Class 1 or Class 2 instrument.