Comparison

SPL Graph vs AudioLayer

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

SPL Graph

This app analyzes sound pressure levels and environmental noise in real-time. It logs audio, captures video, and performs frequency analysis, with options for advanced octave band analysis and professional microphone integration. Receive email notifications for exceeding noise limits and auto-save data for continuous monitoring.

Highlights
  • Real-time sound pressure level analysis
  • Audio recording and playback
  • Optional video capture
  • Octave and 1/3 octave band analysis
  • 3D frequency plot
  • Ln SPL value calculation
  • Email notifications for noise limits
Features
Read full description

SPL Graph is an audio Sound Pressure Level (SPL) environmental noise analyzer, real-time frequency analyzer, chart recorder and data logger. It includes: * Plot sound level over time * Record audio while plot is running, playback to identify sounds that may have caused problems * Capture video of events (optional in-app purchase) * Do octave and 1/3 octave band analysis (optional in-app purchase) * Show a 3D Plot of octave or 1/3 octave results * Calculate Ln SPL values, L01, L10, L50, L90, L95, LMax and LMin * Email notifications when sound exceeds pre-set limits * Auto-save results after set intervals, and email the results to you * Start another plot after auto-saving for continuous operation SPL Graph works by averaging the SPL for a period of time that can vary from 0.1 second to 60 minutes, applying an optional weighting filter, and plotting the sound level, recording the raw audio signal, if recording is turned on. For sound intervals of 1.0 second to 60 minutes, the optional octave and 1/3 octave logging modules allows storing the spectrum of the sound, for each interval. The app works very well with the built-in iOS device microphone. To upgrade the app to true professional standards, add our iTestMic, iPrecisionMic, or iAudioInterface2 with an appropriate microphone, and get ANSI or ISO Type 1 or 2 results. With iPrecisionMic, you can send the system in to our calibration lab and get a calibration certificate for ISO 61672 and ANSI S1.4. SPL Graph can record up to 24 hours of sound level data, with single second resolution. The graph starts with a one-minute plot window, and as a minute is recorded, the graph re-scales automatically and adds another minute to show the data collected so far. The overall SPL level, or LEQ, is displayed for whatever portion of the test is showing on the graph. Tap the play button to play back the recorded audio, and you can use the cursor to scrub the audio location on the graph. Use this feature to listen to events that you can see on the graph. With the optional octave logging module, you can also record the octave or 1/3 octave band levels. And, you can view the data on the 3D plot for a graphical view of frequency over time. You can scroll and scale the graph vertically, in dB, by using standard swipe and pinch gestures. You can also scroll and expand and contract the time axis using gestures. Zoom out to a full 24 hours, or zoom in to a single minute, showing second resolution. Double-tap the screen to zoom out to show the entire graph on the screen. The time scale grid changes dynamically, highlighting minutes, ten-minute, and hour lines as as it runs. As the graph runs, the overall LEQ (average SPL) for the entire time period is computed and displayed on the screen. Swiping across the graph brings up a cursor that displays the exact dB level and time for any point on the graph. You can turn on audio recording, so that you have a record of the sounds that were happening while the graph was being stored. You can use this to figure out exactly what the sound was that caused a peak on the graph, for example. Recordings can be compressed or uncompressed. If you exit the app, or are interrupted with a phone call, the graph data will not be lost. SPL Graph will automatically save the graph, and reload it when you next open the program. You can also save a graph in one of ten files on the iPhone, so that you can recall the graph later. SPL Graph supports saving graphs directly on your iOS device. You can recall these graphs and bring them up on the screen, and listen to the sounds that were made while the graph was recorded. You can also store an image of the screen to your photo roll. Use Dropbox or iTunes Files Sharing to export the results to your computer. You can also export data in tab-delimited files for XLS import using iCloud. The filters are all ANSI type 1 or better, and include A-weighting, C-weighting, and all octaves band filters from 32 to 16kHz.

About

AudioLayer

This app is a powerful mobile multi-sampler for music production, offering advanced features for creating and manipulating complex instruments. It integrates seamlessly with iOS production environments and supports iCloud for easy collaboration and storage.

Highlights
  • Streaming Sample Engine (SSE)
  • Hierarchical Layer and Zone editing
  • Seamless Instrument Switching (SIS)
  • Integrated audio sample recorder
  • Auto Sampler for hardware synths
  • AUv3 AudioUnit integration
  • iCloud storage and collaboration
Features
Read full description

AudioLayer satisfies the most sought after gap for contemporary music production on iOS devices. AudioLayer is a full featured open standard audio multi-sampler pushing the boundaries beyond what has been available even in the desktop music production worlds. And all this integrated in all relevant iOS production environments especially the emerging AUv3 AudioUnit standard. - SSE - Streaming Sample Engine - The ultra efficient Streaming Sample Engine SSE is capable of playing hundreds of voices of big multi-sampled instruments even in strictly resource limited applications like using multiple instances of AudioLayer in AudioUnit host environments. Innovative features like Sub Sample Looping for perfect loops even in the audible range extend the range of applications even further. - Multiple storage options - The consequent usage of the open file structure of the Files app makes organising even large sample libraries a breeze. Sample recordings and Instrument designs made with AudioLayer are seamlessly available across all your devices and desktop using either iCloud storage or external SSD. The iCloud option opens up new forms of collaborations with musicians all around the world to share your creations and work together. - Multi Scope Editing - To support the creation of complex multi-sampled instruments AudioLayer allows you to use a hierarchical structure of Layers and Zones each with it’s own sound manipulation parameters. A unique element of AudioLayer is the possibility to decide for each Zone at which Scope level your editing apply: For the all Zones in the Instrument, for the Layer only or individually for this Zone only. This opens a whole new world of creative options for sound mangling. For sound manipulation you can use a full set of Filters, Envelopes and LFOs to shape the pitch, timbre and level of the sound of each Zone. SIS - Seamless Instrument Switching The unique architecture of the Streaming Sample Engine allows for instant loading of even complex instruments and makes this switching from one Instrument to the next without cutting off the sound! And this includes of course also different effect settings - Easy Design Workflow - The built in audio sample recorder let you create Instruments on the fly in seconds. The Music Effect AudioUnit / Audiobus effect plugin of AudioLayer let you record multi-samples semi automatically directly inside your preferred host and instantly create an Instrument with the help of several Auto mapping options available. This includes file name based mapping of key ranges and velocities and automatic pitch detection. For the creatives we’ve also integrated a special “Single Cycle Waveform” detector making the use of this special files a breeze. - Auto Sampler feature for easy creation of Sample Instruments from hardware synthesiser. - Versilian Studio Sample Library ( VCSL/VSCO ) with excellent strings and orchestra samples for free download - Exchange libraries with XinematiX App Integration • Stand-alone App • Sample import for EXS24 and SFZ Format • AUv3 AudioUnit Instrument and Music Effect • Inter App Audio • Audiobus 3 Input/Effect with state saving support. • Audio recorder with share function. • Ableton Link compatible.

Screenshots

SPL Graph3 screens
AudioLayer4 screens

Verdict

The call

The clearest difference is rating: AudioLayer at 4.4 against SPL Graph's 3.7. AudioLayer also leads on update cadence (fortnightly vs every 6 months) and ratings volume (179 vs 3). SPL Graph's advantage is price ($9.99 vs $12.99) and review sentiment (64% vs 56%). On ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

SPL Graph costs $9.99 and AudioLayer $12.99 up front. SPL Graph sells 5 in-app purchases, starting at $19.99 per month and AudioLayer sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

AudioLayer holds the better App Store score, 4.4 against 3.7. That said, the two scores are not equally well evidenced: AudioLayer has 179 ratings behind it against 3, so its average is the more settled of the two. Written reviews complicate that: 64% of SPL Graph's written reviews are positive against 56% of AudioLayer's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

SPL Graph ships an update every 6 months, AudioLayer fortnightly. The most recent releases landed on October 3, 2026 and October 6, 2026 respectively.

Scorecard7 real differences · 3 level
SPL Graph versus AudioLayer: the parameters behind the verdict, then further details
ParameterSPL GraphAudioLayer
Price$9.99 — better$12.99
Rating3.7 (3 ratings)4.4 (179 ratings) — better
Positive reviews64.3% of reviews — better55.6% of reviews
Number of ratings3179 — better
Update frequencyEvery 6 monthsFortnightly — better
AdsNoNo
In-app purchasesYesYes
MonetizationPaidFree with in-app purchases — better
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.013.0 — better
Further details — not scored
Size29 MB242 MB
Age rating4+4+
DeveloperAndrew SmithHarry Gohs

Customer experience

SPL Graph

All ratings3 ratings
Positive66.7%
Neutral0.0%
Negative33.3%
Written reviews14 reviews
Positive64.3%
Neutral7.1%
Negative28.6%

AudioLayer

All ratings179 ratings
Positive81.6%
Neutral5.6%
Negative12.8%
Written reviews124 reviews
Positive55.6%
Neutral16.1%
Negative28.2%

Bugs and requests

SPL Graph

Not enough reviews yet to summarise bugs or requests.

AudioLayer

Reported bugs

17 issues
  • App crashes on startup (splash screen)
  • Reverb and chorus effects cause sound to disappear
  • Pitch resets to -24 after stopping Logic Pro playback
  • Layer voice polyphony controls not working properly
  • SFZ batch import distributes samples incorrectly across layers
Show 12 more
  • EXS24 import fails for complex instruments (pianos, drum kits)
  • MIDI source names display as 'Unknown Name'
  • Plugin window resizing required to access all controls
  • Sample end marker positioning doesn't work in all view sizes
  • Soundfont import module shows as missing despite purchase
  • App becomes unresponsive when loading complex instruments
  • Control Change 11 (Expression) not received
  • Autosampler function button missing after update
  • Settings not saved properly as AUv3 plugin
  • Instrument loading defaults to first instrument in host
  • Click/pop noises in sustain loops
  • Inter-Audio (IAA) compatibility broken

Requested features

17 requests
  • Time-stretching/pitch-shifting capability
  • Program Change MIDI support
  • Undo/Redo functionality
  • GigaSampler .gig library support
  • Soundfont SF2 import (now paid feature)
Show 12 more
  • MIDI learn for real-time parameter control
  • Expression (CC11) and other CC support
  • Multi-output support for individual zone routing
  • Batch import and file management improvements
  • Instrument selection screen persistence in MIDI mode
  • Bit reduction effect for vintage sampler emulation
  • Better local file management and folder organization
  • Modulation wheel pitch control
  • Transposition features
  • Disk streaming for larger libraries
  • Macro/customizable GUI support
  • Purge unused samples function

In-app purchases

5 purchases

SPL Graph

Subscriptions3
  • Remote Noise Monitoring7 Days trial$19.991 Month
  • Remote Noise Mid Level7 Days trial$79.991 Month
  • Remote Noise Large7 Days trial$149.991 Month
One-time2
  • Octave Band SPL Logging$9.99
  • Video Capture Option$19.99
1 purchases

AudioLayer

One-time1
  • SoundFont Import$3.99

Questions

Is SPL Graph free?
SPL Graph costs $9.99, and also offers in-app purchases.
Is AudioLayer free?
AudioLayer costs $12.99, and also offers in-app purchases.
Which has better reviews, SPL Graph or AudioLayer?
AudioLayer is rated higher. SPL Graph averages 3.7 out of 5 from 3 ratings, while AudioLayer averages 4.4 from 179 ratings.
Do SPL Graph or AudioLayer have ads?
Neither SPL Graph nor AudioLayer shows ads.
Which is updated more often, SPL Graph or AudioLayer?
SPL Graph ships an update every 6 months, and AudioLayer fortnightly. Most recently, SPL Graph was updated on October 3, 2026 and AudioLayer on October 6, 2026.

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