Smaart
Smaart is a professional acoustic test and measurement software platform developed by Rational Acoustics, widely used in the audio industry for analyzing and optimizing sound systems in real-time environments such as live events, installations, and studios.[1] It functions as a single- and dual-channel fast Fourier transform (FFT) analyzer, enabling users to measure frequency response, phase, impulse response, and sound pressure levels (SPL) through modes including Real-Time Mode for spectrum analysis (real-time analyzer or RTA, and spectrograph), Transfer Function for system alignment, and Impulse Response for detailed acoustic profiling.[2] Originally developed in 1995 as an affordable alternative to expensive hardware-based audio analyzers, Smaart emerged during a time when software solutions offered greater flexibility and functionality for sound engineers.[2] The software underwent several ownership changes before Rational Acoustics was founded in 2008 specifically to advance its development, provide enhanced user support, and expand educational resources for the pro audio community.[2] Key evolutions include the transition to version 9 in 2022, which introduced a unified codebase across editions, improved multi-channel SPL monitoring, and ongoing updates through v9.6 as of 2025 for enhanced stability and features, while support for the legacy v6 edition ended on August 16, 2024.[1][3][4] Smaart is available in four editions tailored to different user needs: Smaart Suite, the flagship version with all measurement modes (Real-Time, Impulse Response, and SPL); Smaart RT, focused on real-time spectrum and transfer function analysis; Smaart LE, a simplified real-time edition with fixed configurations for basic applications; and Smaart SPL, a standalone tool for SPL metering and logging.[1] Compatible with Windows and macOS, it supports perpetual or annual subscription licensing and integrates with hardware interfaces for live audio input, making it essential for tuning public address systems, verifying installations, and troubleshooting acoustic issues.[1]Overview
Development and Ownership
Smaart was initially developed in 1995 by Sam Berkow and Alexander "Thorny" Yuill-Thornton II under the banner of SIA Software, aimed at providing a cost-effective software alternative to expensive hardware-based audio analyzers prevalent at the time.[5][6][7] The software emerged from the need for accessible real-time acoustical measurement tools in professional audio, leveraging personal computers to democratize sound system analysis.[8] The first commercial release occurred in 1996 as JBL-SMAART, licensed to JBL Professional's audio division, marking its entry into the market as a PC-based optimization and measurement tool.[5][9] Ownership transitioned in 1999 when the license moved to Eastern Acoustic Works (EAW), where it underwent further refinements, including the release of version 6 in 2006.[10][11][12] In 2008, Rational Acoustics was founded by industry veterans Jamie Anderson, Karen Anderson, Calvert Dayton, and Adam Black to focus on acoustic measurement software and education.[13] The company acquired full ownership of the Smaart product line from EAW in 2009, becoming its independent developer and steward.[10][11] Since then, Rational Acoustics has driven the continuous evolution of Smaart for over 15 years, incorporating advancements like multi-platform support to maintain its relevance in professional audio workflows.[8][14]Core Technologies and Platforms
Smaart employs Fast Fourier Transform (FFT)-based dual-channel analysis as its foundational technology for real-time acoustical measurements, enabling the computation of transfer functions that compare a reference signal with a measured signal to assess system performance.[15] This approach allows for source-independent measurements, where diverse signals such as speech, music, or pink noise can serve as the reference, facilitating analysis under realistic operating conditions without requiring specialized test tones.[16] The software supports a range of audio drivers to ensure compatibility with professional audio hardware, including ASIO and WAV/WDM on Windows for low-latency input/output, and Core Audio on macOS for native system integration.[17] It integrates seamlessly with external hardware, such as calibrated measurement microphones (e.g., omnidirectional models like the Earthworks M30) and multi-channel audio interfaces, which provide the necessary inputs for dual-channel operations and ensure accurate signal capture in acoustical environments.[18] Smaart's platform requirements emphasize modern computing capabilities, running on Windows 10 (64-bit) or later and macOS 10.14 (Mojave) or newer, with a minimum of a 6th-generation Intel Core i5 processor (or equivalent), 4 GB RAM, and 64-bit architecture support.[17] Extending its reach to mobile devices, Rational Acoustics released the Smaart RTA app for iOS in 2025, offering single-channel real-time analysis, including spectrum and SPL monitoring, optimized for iPhone and iPad users in field applications.[19]Measurement Modes
Real-Time Mode
The Real-Time Mode in Smaart enables ongoing frequency-domain analysis of audio signals, allowing audio engineers to monitor and adjust live sound systems in real time through FFT-based spectrum and phase measurements. This mode supports unlimited simultaneous measurements across multiple input devices, facilitating comprehensive system evaluation without interrupting performance. It emphasizes dual-channel coherence tracking to ensure reliable data amid varying signal conditions.[20][21] The Real-Time Analyzer (RTA) provides single- and dual-channel FFT-based spectrum analysis, displaying magnitude and phase in linear, logarithmic, or all-pass filtered views. It offers fractional-octave banding up to 1/48th octave resolution, with options for live averaging (e.g., 2-16 FIFO blocks or 1-10 seconds) and smoothing to reduce noise while preserving detail. Additional overlays include peak holds, target curves, and total harmonic distortion (THD) indicators, enabling precise identification of frequency imbalances during live events.[21][20] The Spectrograph complements the RTA by visualizing time-varying frequency content as color-coded intensity plots, where hue and brightness represent amplitude levels over a scrollable history. Users can adjust dynamic range, slice height, and banding (up to 1/48th octave) in full color or grayscale modes, making it ideal for detecting transient anomalies like feedback or tonal shifts in real-time audio streams.[21][20] The Transfer Function tool performs dual-channel analysis to measure system response, calculating magnitude, phase, and coherence between a reference input signal and the measurement output. It employs multi-time window (MTW) or fixed FFT sizes (128 to 128K points) with progressive averaging (1-10 traces or infinite) and smoothing up to 1/48th octave for stable traces. The core computation derives the transfer function as H(f) = \frac{Y(f)}{X(f)}, where Y(f) is the complex output spectrum and X(f) is the complex input (reference) spectrum, providing essential data for frequency and phase corrections. Coherence is displayed as squared or unsquared values to assess measurement reliability, with features like automatic delay tracking and AES-75 support enhancing accuracy in professional setups.[21][20] Within the Transfer Function, the Live Impulse Response derives time-domain waveforms in real time from the frequency-domain data, aiding quick delay optimization and phase alignment without full offline processing. This feature generates impulse traces for immediate visual inspection of arrival times and polarity, supporting rapid adjustments in dynamic live environments.[21][20] In live audio applications, Real-Time Mode tools like the RTA and Transfer Function are primarily used for continuous monitoring and corrective equalization of frequency responses, ensuring balanced sound reproduction across venues. These measurements can integrate briefly with SPL monitoring for holistic level and spectrum oversight.[20][21]Impulse Response Mode
Impulse Response Mode in Smaart facilitates time-domain measurements by capturing and analyzing impulse responses (IRs) to characterize room acoustics, system delays, and reflections. This mode allows users to generate IRs using multiple excitation techniques, enabling precise evaluation of acoustical properties in environments such as concert halls, studios, or conference rooms. Unlike continuous monitoring tools, it focuses on discrete captures that provide detailed temporal information about sound propagation.[22] IR generation in this mode supports swept-sine signals, which sweep through frequencies logarithmically to minimize noise interference; periodic noise excitation for steady-state analysis; dual-channel transfer function methods, comparing reference and measurement signals; and single-channel direct IR capture via triggered sources like starter pistols or balloon pops. These methods accommodate various measurement scenarios, from controlled tests to field applications, with single time window FFT sizes ranging from 128 to 512k samples for resolution control. Unlimited simultaneous IR measurements can be performed and stored for comparative analysis.[22][23] Display options include linear and logarithmic waveform views for direct time-domain visualization; envelope traces to highlight amplitude variations; Energy Time Curve (ETC) for identifying discrete reflections and their levels relative to the direct sound; and cumulative decay curves derived from reverse integration. Spectrogram, frequency, and histogram graphs further aid in examining time-frequency relationships and statistical distributions. These visualizations help users pinpoint early reflections, modal ringing, or diffusion patterns in the acoustical response.[23][22] Key acoustical metrics computed from the IR include Reverberation Time (RT60), Early Decay Time (EDT), Clarity Indices (C50 and C80), and Speech Transmission Index (STI). RT60 quantifies the time required for the sound pressure level to decay by 60 dB after the source stops, calculated via linear regression on the Schroeder integral of the squared impulse response plotted against the logarithm of time; the integration typically starts 5 dB below the direct sound peak and extends 20-30 dB into the decay, ensuring the lower end remains at least 10 dB above the noise floor. EDT measures the initial decay rate over the first 10 dB drop, also using the Schroeder method, to assess perceived reverberance. C50 and C80 evaluate speech or music clarity by comparing early (0-50 ms) to late energy ratios, with automatic octave and 1/3-octave bandpass filtering; values above 0 dB indicate good clarity for music (C80) or speech (C50). STI, including variants like CIS and STIPA, assesses speech intelligibility under noiseless or noise-present conditions by modulating the IR across octave bands. These metrics are presented in an all-bands table view with user-definable frequency bandpasses.[23][22] In practice, Impulse Response Mode is used to identify specific reflections and delays for optimizing loudspeaker placement, verify phase alignment in systems, and analyze overall room acoustics, such as uniformity of reverberation or presence of echoes. For instance, ETC displays can reveal comb filtering from parallel surfaces, guiding acoustical treatments. This mode complements real-time frequency-domain analysis by providing phase and timing verification through captured IRs.[22]Sound Pressure Level Mode
Smaart's Sound Pressure Level (SPL) Mode provides specialized tools for precise monitoring and logging of acoustic levels, essential for ensuring compliance with noise regulations and evaluating audio system performance in real-world settings. This mode supports multi-channel metering, enabling simultaneous SPL measurements from multiple input sources such as microphones connected to audio interfaces.[24][25] The metering options include frequency weightings of A (simulating human ear response for hearing protection assessments), C (emphasizing low frequencies for rumble and impact evaluation), and Z (flat, unweighted response for broadband measurements). Time detectors available are fast (with a 125 ms exponential averaging constant for capturing rapid fluctuations), slow (1 s constant for smoother trending), and impulse/peak (for instantaneous maximum levels to detect short bursts).[26][27] Key calculations encompass Leq (equivalent continuous sound level, representing average energy over time) and Lmax/Lmin (maximum and minimum levels within intervals), configurable across user-defined periods from 1 second to 24 hours. These metrics facilitate exposure assessments, such as LAeq over 15 minutes for event noise limits, and support additional derived values like L10, L50, and L90 for statistical level distribution.[27][24] Logging capabilities allow continuous, timestamped data capture throughout sessions, displayed via customizable history plots that track trends over time. Logged data includes all configured metrics and can be exported in CSV format for external analysis or used to generate PDF reports summarizing session highlights, such as peak exposures and averages. Alarms and remote viewing via web browser further enhance usability for distributed monitoring.[24][25] Integration with the Real-Time Analyzer (RTA) enables frequency-weighted SPL computations, for instance, in 1/3 octave bands, to isolate contributions from specific frequency ranges without requiring full spectral decomposition.[24] For dedicated SPL applications, a standalone edition called Smaart SPL offers the complete mode functionality, including multi-channel support and compliance-grade metering with Class 1 or 2 hardware, at an accessible price point without broader analysis features.[25]Applications
Live Sound System Tuning
Smaart facilitates the optimization of live sound systems by providing real-time analysis tools to measure and adjust audio responses during events, ensuring even coverage and clarity for audiences. The software relies on dual-channel FFT-based measurements in real-time and impulse response modes to capture system performance data, allowing engineers to make precise adjustments to equalization (EQ), delays, and levels. This process is essential for temporary setups like concerts and festivals, where rapid tuning minimizes issues such as uneven frequency response or timing discrepancies.[28] The tuning workflow begins with microphone placement at representative audience positions, typically at ear height (about 5 feet 6 inches for standing listeners or 4 feet for seated, per ANSI standards), avoiding edges of loudspeaker coverage where high frequencies may roll off. Multiple microphones, often 6 or more, are used for spatial averaging to account for venue variations, with placements at least 2√(V/cT̂) meters from the source to reduce near-field effects. Next, the reference signal is set up using a signal generator in Smaart to produce pink noise (random or pseudorandom, with a 512K cycle length at 48 kHz), routed through the mixing console to the loudspeakers and split via a Y-cable to the reference input channel for direct comparison. This ensures the input signal serves as a stable baseline for analysis.[29][28] Transfer function measurements then compare the reference and measurement signals to inform EQ and delay alignment. For EQ, engineers capture the system's magnitude response and apply parametric filters to flatten peaks and dips, often inverting the display to visualize corrective cuts directly on the console's EQ interface. Delay alignment uses the Delay Finder tool or energy time curve (ETC) in impulse response mode to identify time offsets (in milliseconds), compensating for path differences between speakers by adding delays— for instance, aligning front fills to mains at the acoustic crossover point. Throughout, dual-channel coherence is monitored, with values above 0.8 indicating reliable data; lower coherence prompts checks for noise, gain mismatches, or improper signal routing, using temporal averaging (1-10 seconds) for stability.[29][28] Common issues are identified and corrected using Smaart's visual traces. Comb filtering, appearing as magnitude notches and phase irregularities from reflections, is detected in the spectrograph (vertical streaks) or transfer function plots and mitigated by optimizing microphone proximity to surfaces (e.g., floor placement to push nulls above audible frequencies) or adjusting speaker positions. Phase mismatches, shown as differing trace slopes, are resolved by fine-tuning delays until phases align linearly, ensuring coherent summation across the system. Gain before feedback is maximized by gradually increasing microphone gain while monitoring the real-time analyzer (RTA) or spectrograph for ringing frequencies, then applying narrow notches (e.g., 1/10-octave bandwidth) at those points to suppress feedback without over-EQing. Best practices include verifying adjustments with live averaging across multiple positions and maintaining excitation levels 35-45 dB above ambient noise for accurate coherence.[29][28] In practice, Smaart is applied to tune line arrays by capturing spatial averages from several audience points along the array's coverage, adjusting splay angles and EQ to achieve uniform response— for example, applying a high-shelf filter at 2 kHz with -4.5 dB to counteract venue-specific high-frequency buildup. Subwoofer integration involves phase and delay alignment to mains, using ETC to match arrival times and leveraging boundary effects (e.g., +6 dB gain near walls, with Q factors up to 8) for low-end extension, as seen in ground-stack configurations where delays of 3-5 ms align subs to tops. Venue equalization uses transfer functions with 1/3-octave smoothing across averaged mic positions to apply broad adjustments, such as boosting midrange for clarity in reverberant spaces (RT60 of 1-1.5 seconds), ensuring the overall response matches target curves like flat or house standards. These techniques enable efficient tuning for events with capacities up to thousands, reducing setup time while enhancing audio fidelity.[29][28]Acoustical Design and Analysis
Smaart plays a crucial role in acoustical design and analysis for permanent installations, enabling professionals to evaluate and optimize fixed audio systems and room environments. Acoustical consultants utilize Smaart's measurement capabilities to assess speech intelligibility, clarity, and reverberation in spaces such as theaters, conference rooms, and broadcast facilities. By capturing impulse response (IR) data, Smaart facilitates the calculation of the Speech Transmission Index (STI), a key metric for predicting speech intelligibility under various acoustic conditions. This is particularly valuable in design phases where ensuring clear communication is essential, as STI values derived from IR measurements help validate whether a space meets standards like those outlined in IEC 60268-16.[30][8] In room acoustics modeling, Smaart's IR mode allows for detailed analysis of environmental responses, including the measurement of reverberation times (RT60) to inform treatments for controlling reverberation in studios and performance venues. For instance, in recording studios, Smaart helps identify modal resonances—low-frequency standing waves that can color sound reproduction—through examination of IR decay patterns and early reflection analysis. Similarly, diffusion patterns can be assessed by analyzing spatial variations in IR measurements across multiple positions, ensuring even sound distribution without hotspots. These applications extend to HVAC noise assessment, where Smaart's Sound Pressure Level (SPL) mode monitors background noise levels from ventilation systems, helping designers achieve NC (Noise Criteria) ratings compliant with standards like ASHRAE guidelines.[29][25] Loudspeaker design verification benefits from Smaart's transfer function tools, which acousticians apply to fixed installations for alignment and performance evaluation. Designers measure frequency response, phase, and coherence to confirm that loudspeaker arrays meet specifications in permanent setups like conference halls. This iterative process ensures that designed systems perform as intended in real-world conditions, bridging theoretical modeling with on-site verification.[8][31]Editions and Market
Available Editions
Smaart is offered in several editions tailored to different levels of audio measurement needs, all derived from the same v9 codebase to ensure consistency in user interface and core operations.[1] These editions share a fundamental graphical user interface (GUI), command structure, operational paradigms, hotkeys, and update pathways from version 7 onward, allowing users to transition seamlessly between them while focusing differences on available measurement modes and features.[1] The flagship Smaart Suite provides full access to all core measurement modes, including Real-Time Mode for spectrum analysis and transfer functions, Impulse Response Mode for reverberation and intelligibility metrics like T60 and STI, and SPL Mode for comprehensive sound pressure level monitoring and logging.[32] Licensing options include a perpetual license at $1,299 for new users or an annual subscription starting at $399, with additional installations available for $520 each under perpetual terms.[33] Smaart RT focuses exclusively on Real-Time Mode, offering tools such as real-time analyzer (RTA), spectrograph, transfer function analysis, and live impulse response capabilities, but excludes full Impulse Response and advanced SPL features.[32] It is priced at $899 for a perpetual license or $279 annually via subscription, with upgrades from prior versions like v8 available for $450.[33] For entry-level users, Smaart LE delivers a simplified version of Real-Time Mode with fixed configurations for spectrum and transfer function measurements, emphasizing ease of use without customizable advanced settings or other modes.[32] This edition costs $499 perpetually or $159 per year on subscription and is frequently bundled with compatible hardware interfaces.[33] Smaart SPL is a dedicated tool for SPL monitoring and logging, supporting multi-channel metering for noise assessment and compliance, without Real-Time or Impulse Response modes.[32] It is available for $349 as a perpetual license, targeting applications requiring precise acoustical data recording.[33] Additionally, Rational Acoustics provides Smaart RTA, a mobile application for iOS devices that offers single-channel real-time spectrum analysis and basic SPL monitoring in a portable format.[19] The app offers a 7-day free trial. The base version requires a monthly subscription at $1.99, annually at $19.99, or lifetime purchase at $59.99. The Pro upgrade, which unlocks advanced features like extended history views, is available via monthly subscription at $4.99, annually at $49.99, or lifetime at $149.99; no Android version exists as of 2025.[34]| Edition | Key Modes/Features | Perpetual Price | Subscription Price (Annual) |
|---|---|---|---|
| Smaart Suite | Real-Time, Impulse Response, Full SPL | $1,299 | $399 |
| Smaart RT | Real-Time only (RTA, Transfer Function, Live IR) | $899 | $279 |
| Smaart LE | Simplified Real-Time | $499 | $159 |
| Smaart SPL | SPL monitoring/logging only | $349 | N/A |
| Smaart RTA (iOS) | Single-channel RTA and SPL (mobile, 7-day trial) | $59.99 (base lifetime) | $19.99 (base), $49.99 (Pro) |