# SPL Reference — Sound level meter & analysis

> Sound level meter & analysis (iPhone/iPad app by Direct Sound Records Ltd.)

- Source: https://appshunter.io/ios/app/spl-reference/id6806757498 (this page in markdown: same URL + `.md`)
- Developer: [Direct Sound Records Ltd](https://appshunter.io/developer/1896279797)
- Category: Utilities, Productivity
- Price: Free with in-app purchases
- Age rating: 17+
- Requires: iOS 17.0 · 6 MB
- Released: 2026-09-09
- Data updated: 2026-10-16

## What is SPL Reference?

Hear your system. See your room.

SPL Reference combines sound-level measurement with Room Map, a new way for Hi-Fi enthusiasts to explore how bass changes across a listening room. Measure at several positions and see areas of relatively high and low sound pressure at the selected frequency, helping you investigate uneven bass and make more informed speaker and listening-position choices.

EXPLORE YOUR LISTENING ROOM

• Create a rectangular room and follow a guided 9- or 12-point survey, or customise your measurement positions.
• Explore frequency-selectable heatmaps with 1/12- or 1/3-octave bands.
• Use generated bass pink noise through your playback system, or a stable external pink-noise source.
• Review individual points, capture-quality notes and a repeat measurement at the reference position.
• Save maps in Sessions, organise them in projects and export the survey data.

A COMPANION TO ROOM REFERENCE

Use SPL Reference alongside the separately available Room Reference app to add measured spatial bass comparisons to your room investigation. We are working to integrate the two apps; direct integration is not included in this release.

MEASURE WITH CONTEXT

• Live A-, C- and Z-weighted measurements
• Fast, Slow and Impulse time responses
• LAeq, LAFmax, LCpeak and time-history views
• Pause, resume, event markers and integrity evidence
• Clear distinction between indicative readings and reference-calibrated chains

ANALYSE AND DOCUMENT

• 1/1- and 1/3-octave frequency analysis, spectrum and spectrogram history
• Statistical exceedance levels from L1 to L99
• Noise-exposure assessment using NIOSH, OSHA and configurable models
• Projects, notes, photographs and optional location evidence
• Microphone profiles, acoustic calibration records and drift checks
• Professional PDF reports for ordinary sound-level measurements

Browse the public measurement archive from inside the app. Measurements are never uploaded automatically.

START FREE. UPGRADE ONCE.

The free tier includes the built-in microphone, five active measurement minutes per calendar month, two saved measurements and one project. Room Map and advanced features require Lifetime Professional Unlock, which removes the free limits with one purchase and no subscription. Room Map is included for existing Lifetime Professional owners.

ABOUT YOUR RESULTS

Room maps show the combined response of your speakers and room at one microphone height. Colours compare the selected frequency across measured positions. Uncalibrated maps display relative levels in dBFS. Results depend on the microphone, calibration, playback setup and measurement conditions.

SPL Reference distinguishes indicative and calibrated workflows and does not claim that an unvalidated device is a certified sound-level meter. Occupational-noise results support assessment and documentation; they do not replace professional judgement or applicable legal requirements.

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Lifetime Professional Unlock | $39.99 | one-time |


## Is SPL Reference safe?

Not enough ratings yet to assess SPL Reference.

## Is SPL Reference legit?

SPL Reference appears legitimate, with a few gaps. The AppsHunter Legitimacy Score for SPL Reference is 65 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 3 releases)

### 1.2 — 2026-10-05

Introducing Room Map for Hi-Fi listening rooms.

• Map relative bass levels across your room to reveal areas of higher and lower sound pressure.
• Explore frequency-selectable heatmaps with 1/12- and 1/3-octave bands.
• Follow guided measurement points, review captures and recheck your reference position.
• Save room maps in Sessions, organise them in projects and export survey data.

Room Map is included with Lifetime Professional, including existing purchases.

Use it alongside Room Reference today. Direct integration between the apps is in development and is not included in this release.

### 1.1 — 2026-09-24

New in 1.1

• Continue active measurements in the background, with Lock Screen and Dynamic Island Live Activity support.
• Browse the public measurement archive inside the app, with improved contribution review, retry and privacy controls.
• More reliable microphone and input selection, clearer connected-source status, and safer saved-path matching.
• Expanded calibration workflows with improved CEL-177/CEL-182 handling, gain and headroom guidance, calibration-file compatibility, and microphone response correction.
• Richer sessions and professional reports, improved charts and evidence handling, long-session performance improvements, and project photograph fixes.
• Optional 180° portrait rotation.
• Measurement accuracy, persistence, and stability improvements.

### 1.0 — 2026-09-09

No release notes.

## More apps by Direct Sound Records Ltd

- [Resonance Lab](https://appshunter.io/ios/app/resonance-lab/id6766353005)
- [Groove Scope](https://appshunter.io/ios/app/groove-scope/id6790797152)

All apps by Direct Sound Records Ltd: https://appshunter.io/developer/1896279797

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*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 2026-10-16.*