# SoundMeter 2D — Sound mapping made smart! > Probabilistic sound field estimation and mapping for acoustic analysis. (iPhone/iPad app by DENNIEL JEAN-FRANCOIS.) - Source: https://appshunter.io/ios/app/soundmeter-2d/id6737282025 (this page in markdown: same URL + `.md`) - Developer: [DENNIEL JEAN-FRANCOIS](https://appshunter.io/developer/1523880701) - Category: Utilities, Music - Price: Free with in-app purchases - Age rating: 4+ - Requires: iOS 18.6 · 21 MB - Languages: American English - Released: 2025-02-27 - Data updated: 2026-06-10 - Monetization: free with in-app purchases - User reviews in markdown: https://appshunter.io/ios/app/soundmeter-2d/id6737282025/reviews.md ## What is SoundMeter 2D? WHY SOUNDMETER 2D Acoustic field mapping usually requires lab software, multiple instruments, and significant post-processing. SoundMeter 2D brings probabilistic sound field estimation directly to your iPhone, using the same statistical framework used in research-grade spatial acoustics. WHAT SOUNDMETER 2D DOES SoundMeter 2D uses Gaussian Process Regression with an anisotropic Matérn 5/2 covariance kernel to interpolate a sound field from a sparse set of measurements. Hyperparameters are optimized by maximizing the Log Marginal Likelihood. The result is not a simple interpolation, it is a probabilistic model of the acoustic field, including spatial uncertainty. For each third-octave band, the app produces two maps: - the estimated SPL field (posterior mean) - the 95% confidence interval map (posterior uncertainty) This allows you to see not only what the field looks like, but how reliable that estimate is given your measurement density. KEY FEATURES - Anisotropic GPR interpolation, spatial correlation adapts to the geometry of the space - Third-octave band analysis from 25 Hz to 16 kHz - 95% confidence interval mapping alongside SPL estimate - AR-guided point placement via a dynamic real-space grid - Statistical pre-processing: Tukey IQR outlier rejection and spatial sampling checks - Point-to-point level difference analysis - Structured PDF export, maps and summaries ready for technical reports DESIGNED FOR - Acousticians and engineers needing rapid, spatially resolved field estimates during site surveys or diagnostic work. - Researchers and educators teaching spatial acoustics, statistical field estimation, or acoustic measurement methodology. - Audio system integrators exploring coverage patterns and identifying weak zones before committing to loudspeaker placement. MEASUREMENT LIMITATIONS SoundMeter 2D produces indicative measurements. It is not a certified instrument under IEC 61672-1 or any equivalent standard, and is not intended for regulatory, legal, or normative applications. Results depend directly on the accuracy of the microphone used. The built-in iPhone microphone provides relative, comparative data suitable for exploratory work. For improved accuracy, use of an external Class 2 microphone is strongly recommended. SoundMeter 2D is a field exploration and diagnostic support tool. For any application requiring certified acoustic data, accredited instrumentation and procedures remain mandatory. ## Key features - Probabilistic sound field estimation - Anisotropic GPR interpolation - Third-octave band analysis - 95% confidence interval mapping - AR-guided point placement - Structured PDF export ## Pricing and in-app purchases Base price: Free. **Subscriptions** | Subscription | Price | Period | | --- | --- | --- | | Annual subscription | $59.99 | per year | | Monthly subscription | $5.99 | per month | | Weekly subscription | $2.99 | per 7 days | ## Recent user reviews (2 of 2) All indexed reviews: https://appshunter.io/ios/app/soundmeter-2d/id6737282025/reviews.md ### 4/5 — Good application *2025-03-04, version 1.0* Easy to use. Good idea for sound visualisation ### 5/5 — Very nice app ! *2025-03-04, version 1.0* The tool is accurate and user friendly. I used it to optimise the speaker configuration in my home theatre ## Frequently asked questions about SoundMeter 2D ### What is SoundMeter 2D used for? SoundMeter 2D is used for probabilistic sound field estimation and mapping. It helps acousticians and engineers visualize sound pressure levels and their uncertainty in a given space, aiding in site surveys and diagnostic work. ### Does SoundMeter 2D provide certified acoustic measurements? No, SoundMeter 2D produces indicative measurements and is not a certified instrument under IEC 61672-1 or equivalent standards. It is intended for exploratory work, not regulatory or legal applications. ### What kind of microphone accuracy can I expect with SoundMeter 2D? The accuracy of SoundMeter 2D results depends directly on the microphone used. The built-in iPhone microphone provides relative data, but an external Class 2 microphone is strongly recommended for improved accuracy. ### What are the subscription options for SoundMeter 2D? SoundMeter 2D offers weekly ($2.99), monthly ($5.99), and annual ($59.99) subscription plans for access to its full features. ### How does SoundMeter 2D handle data analysis? The app analyzes sound fields in third-octave bands from 25 Hz to 16 kHz, providing both estimated SPL maps and 95% confidence interval maps to show the reliability of the estimates. ### Can I export my sound field data from SoundMeter 2D? Yes, SoundMeter 2D offers structured PDF export, allowing you to include maps and summaries of your acoustic analysis directly in technical reports. ### Is SoundMeter 2D suitable for educational purposes? Yes, SoundMeter 2D is designed for researchers and educators teaching spatial acoustics, statistical field estimation, or acoustic measurement methodology, providing a practical tool for demonstration and learning. ### How frequently is SoundMeter 2D updated? The latest version of SoundMeter 2D is 3.01, which was last updated on March 19, 2026. This indicates a relatively recent update cycle for the application. ## Version history (last 5 releases) ### 3.01 — 2026-03-19 Fixed bugs in the uncertainty calculation process and PDF report generation. Simplifying the record duration selection ### 3.0 — 2026-03-14 - Improved Gaussian Process Regression Hyperparameter optimization has been overhauled for greater numerical stability, producing smoother, more physically consistent acoustic maps. - Enhanced Class 2 Microphone Uncertainty Uncertainty propagation now accurately reflects the frequency-dependent tolerance margins of Class 2 microphones, delivering more rigorous 95% confidence intervals. - PDF Export Export your session, heatmaps, uncertainty maps, and validation report, as a structured, print-ready PDF. - Adjustable Recording Duration Select your measurement integration time to average out low-frequency temporal fluctuations inherent to pink noise, improving reliability below 100 Hz. ### 2.2 — 2025-12-24 Point-to-Point Analysis : New function to measure and plot SPL attenuation between any two points on the heatmaps. Fixed point labels not displaying correctly. ### 2.1 — 2025-11-19 This update includes: - Enhanced validation reports with practical optimization tips. - Report features more intuitive Dynamic Range metric. - Bug fixes and performance improvements. Thank you for using SoundMeter 2D! ### 2.0 — 2025-11-10 This version is a complete redesign of version 1.0 : - Advanced acoustic modeling with Gaussian Process Regression (GPR) - Dual maps: Sound Level + Uncertainty visualization - Third-octave analysis with outlier detection - Instant validation reports (SNR, sampling quality, optimization tips) - GPS removed - ARKit-only for superior precision ## More apps by DENNIEL JEAN-FRANCOIS - [Mecabud](https://appshunter.io/ios/app/mecabud/id1525069308) - [Mecabudy](https://appshunter.io/ios/app/mecabudy/id1525698735) - [MecaTest](https://appshunter.io/ios/app/mecatest/id6447468608) All apps by DENNIEL JEAN-FRANCOIS: https://appshunter.io/developer/1523880701 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-10.*