SPL
Andrew Smith
SPL measures environmental sound levels with a supported iPhone/iPad microphone setup.
What SPL does
SPL is Studio Six Digital’s digital sound-level meter. The standalone app documents saved results, time and location information, Leq/peak measurements and computer export. It also provides calibration controls and support for specified measurement microphones, whose hardware costs are separate.
How it compares
Saved readings and export versus SPL Meter’s live display
SPL stores readings with time and location information and offers computer export. SPL Meter emphasizes a live meter display, while SPLnFFT combines levels with frequency analysis.
External microphone support, like NIOSH
SPL supports calibration and specified measurement microphones, purchased separately. Like NIOSH Sound Level Meter, its measurement setup depends on the phone and microphone as well as the app.
Features
Hearing checks & protection
- Supported: Sound-level measurement
- Supported: Microphone calibration
- Supported: External measurement microphone
- Supported: Noise-data export
- Supported: Noise metricsLAeq · Maximum · Peak
Privacy & data
- Supported: Data storage1Device · Personal cloud accountiPhone only
- Publisher-wide policy for saved app data; it does not establish that this standalone app exposes every AudioTools cloud/export feature.
App Store ratings & reviews
Complaints
- The newest comment, December 2025, reports an unreadable gray interface. Older comments also object to color choices or iPad scaling; they concern different historical versions.
- Older 2011–2017 reports describe freezing or battery drain, including background-operation complaints. These are not evidence of current-version behavior.
Mixed reports
- Several historical reviewers value having a meter on the phone, but opinions about comparison-meter agreement differ. These comments do not independently validate accuracy or low-frequency measurements.