Comparison

Piano Chord Scales for compose vs SPL Reference

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

Head to head
About

Piano Chord Scales for compose

Easily check piano chords with a comprehensive list and a memory function to save favorites. Play and hear the chords directly on the virtual piano. Expand your saving capacity with an in-app purchase.

Highlights
  • Chord list lookup
  • Save favorite chords
  • Play chord sounds
  • Adjustable sound octaves
  • Edit and delete saved chords
  • Expandable memory slots
Features
Read full description

It is an application that you can easily check the piano chords with a list. You can save the chords you care about in the memory function and see it all at once. You can check the sound by touching the displayed piano. Ā· About sound The sound can be confirmed with the criteria of C4, C3, C2 respectively. You can switch by touching the [C4 button] on the screen. (The initial value is C4.) Ā· How to use memory 1. Touch the [Memory button] you want to save. 2. Select the piano chord you want to save. 3. Touch the [Set button]. The contents of the saved memory can be checked by List. You can also delete and edit in the List. * You can save nine codes. (You can save 24 pieces after purchase.) * There are two memories that can be saved. (Up to nine can be increased after purchase.)

About

SPL Reference

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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.

Screenshots

Piano Chord Scales for compose2 screens
SPL Reference4 screens

Verdict

The call

The clearest difference is ads: SPL Reference at none against Piano Chord Scales for compose's shown. SPL Reference also leads on update cadence (every 2 weeks vs every 5 weeks). Piano Chord Scales for compose's advantage is device support (3 vs 1) and iOS requirement (13.0 vs 17.0). On price and in-app purchases there is nothing between them.

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

CostPrice Ā· In-app purchases Ā· Ads Ā· Monetization

Both are free to download. Piano Chord Scales for compose sells 1 one-off in-app purchase and SPL Reference sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Piano Chord Scales for compose ships an update every 5 weeks, SPL Reference every 2 weeks. The most recent releases landed on November 2, 2026 and October 31, 2026 respectively.

Scorecard4 real differences Ā· 4 level
Piano Chord Scales for compose versus SPL Reference: the parameters behind the verdict, then further details
ParameterPiano Chord Scales for composeSPL Reference
PriceFreeFree
Positive reviews33.3% of reviews—
Update frequencyEvery 5 weeksEvery 2 weeks — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS13.0 — better17.0
Further details — not scored
Size6 MB6 MB
Age rating4+17+
Developerkenji kiuchiDirect Sound Records Ltd

In-app purchases

1 purchases

Piano Chord Scales for compose

One-time1
  • Remove Ad & all functions.$6.99
1 purchases

SPL Reference

One-time1
  • Lifetime Professional Unlock$39.99

Questions

Is Piano Chord Scales for compose free?
Piano Chord Scales for compose is free to download, with in-app purchases available.
Is SPL Reference free?
SPL Reference is free to download, with in-app purchases available.
Do Piano Chord Scales for compose or SPL Reference have ads?
Piano Chord Scales for compose shows ads; SPL Reference does not.
Which is updated more often, Piano Chord Scales for compose or SPL Reference?
Piano Chord Scales for compose ships an update every 5 weeks, and SPL Reference every 2 weeks. Most recently, Piano Chord Scales for compose was updated on November 2, 2026 and SPL Reference on October 31, 2026.

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