# ResoSearch, Acoustic resonance &spectrum measuring > Acoustic resonance and spectrum measurement tool using iPhone microphone and earphone. (iPhone/iPad app by Junichi Watanabe.) - Source: https://appshunter.io/ios/app/resosearch-acoustic-resonance-and-spectrum-measuring/id1217332479 (this page in markdown: same URL + `.md`) - Developer: [Junichi Watanabe](https://appshunter.io/developer/1014493824) - Category: Education, Utilities - Price: Free - Rating: 5.00/5 from 1 App Store ratings · 2 written reviews indexed - Age rating: 4+ - Requires: iOS 10.2 · 14 MB - Languages: American English - Released: 2017-04-07 - Data updated: 2026-06-24 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/resosearch-acoustic-resonance-and-spectrum-measuring/id1217332479/reviews.md ## What is ResoSearch, Acoustic resonance &spectrum measuring? It is an application that performs acoustic measurement using the attached earphone with a microphone. When placing the L side earphone and the microphone on the object to be measured and pressing the Start button, a sound of a specific frequency is output from the L side　earphone and the volume in the measurement object is measured with the microphone. The specific frequency is swept from the start frequency shown in the upper left of the screen to the end frequency shown in the upper right. The measurement takes 2 to 3 minutes. Please measure in a quiet room. If there is a resonance phenomenon, peaks or dips appear on the frequency characteristic graph at the bottom of the screen. Put the L side earphone and microphone in a milk bottle or a wine bottle, then push Start button, you can measure the Helmholtz Resonance of the narrow mouth bottle. Wrap a magazine or a poster in a cylindrical shape, put the L earphone on one side of the cylinder and the microphone on the other side, then press Start button, you can measure the Air Column Resonance. You can adjust the volume with the volume button of the iPhone　before measurement. After the measurement is completed, the circle cursor is displayed. It moves by the screen drag operation with left or right moving, then the Hz value and the dB value of the cursor position are displayed. Measurement can be performed using the built-in speaker and the built-in microphone, but iPhone body itself has an acoustic characteristics and it can not measure well. Measurement can also be performed using the external speaker and the built-in microphone, but there is a possibility that a big sound may come out, which is dangerous. Demonstration Videos Helmholtz Resonance, https://youtu.be/IJ5lT08aEkM Air Column Resonance, https://youtu.be/wv1PsR0SS7k Caution!! Because there of a loud noise, please never put your earphones in your ear. Do not place your ears close to external speakers. ## Key features - Acoustic measurement via earphone microphone - Frequency sweeping from start to end - Displays frequency characteristic graph - Measures Helmholtz Resonance - Measures Air Column Resonance - Adjustable volume before measurement - Cursor for Hz and dB values ## Recent user reviews (2 of 2) All indexed reviews: https://appshunter.io/ios/app/resosearch-acoustic-resonance-and-spectrum-measuring/id1217332479/reviews.md ### 5/5 — Very good *2023-07-09, version 1.2* I have tested this app. It is reliable and friendly to check resonance. You need a high quality earphone with high quality mic. ### 4/5 — This has great potential *2022-04-12, version 1.2* It works fine on my iPad Pro 9.7” … although a proper iPad version would be nice to have. . My only concern, so far, is that the loud ticking [metronome?] seems likely to affect the results … Is it possible to mute this ? . Thanks for what appears to be a great little App. ## Frequently asked questions about ResoSearch, Acoustic resonance &spectrum measuring ### What is ResoSearch used for? ResoSearch is used to perform acoustic measurements and analyze spectrums. It helps users visualize resonance phenomena like Helmholtz and Air Column Resonance by measuring sound frequencies. ### How does ResoSearch measure acoustic resonance? It uses the iPhone's earphone with a microphone. A specific frequency is output from the earphone to the object, and the microphone measures the resulting volume, displaying it on a frequency characteristic graph. ### What types of resonance can ResoSearch measure? ResoSearch can measure Helmholtz Resonance, typically in narrow-mouth bottles, and Air Column Resonance, by wrapping objects like posters into cylinders. ### What devices does ResoSearch support? ResoSearch is supported on iPhone and iPod devices. It was last updated on June 22, 2017, with version 1.2. ### Is ResoSearch suitable for educational purposes? Yes, ResoSearch is designed for educational use, allowing users to observe and understand acoustic resonance phenomena in a practical, hands-on way. ### Can ResoSearch be used without earphones? While measurement can be attempted with the built-in speaker and microphone, the iPhone's own acoustic characteristics can affect accuracy. Using external speakers is possible but potentially dangerous due to loud noise. ### What is the age rating for ResoSearch? ResoSearch has an age rating of 4+, making it suitable for a wide range of users, including younger learners under supervision. ### Does ResoSearch have ads? No, ResoSearch does not contain advertisements. It is a free application without any ads. ## Version history (last 3 releases) ### 1.2 — 2017-06-22 This app has been updated by Apple to display the Apple Watch app icon. The following bug has been fixed. · When you cancel by pressing the CANCEL button during measurement, if you touch the screen before the button display changes to START, the application crashes. ### 1.1 — 2017-05-11 After the measurement is completed, the circle cursor is displayed. It moves by the screen drag operation with left or right moving, then the Hz value and the dB value of the cursor position are displayed. ### 1.0 — 2017-04-07 No release notes. ## Apps similar to ResoSearch, Acoustic resonance &spectrum measuring | App | Rating | Price | Category | | --- | --- | --- | --- | | [Rock ID - Stone Identifier](https://appshunter.io/ios/app/rock-id-stone-identifier/id6469999508) | 4.4 (2,156) | Free | Education | | [EE ToolKit](https://appshunter.io/ios/app/ee-toolkit/id391792609) | 4.7 (1,353) | Free | Education | | [memory OS: Brain Training](https://appshunter.io/ios/app/memory-os-brain-training/id1553283646) | 4.9 (12,850) | Free | Education | | [Calculate84](https://appshunter.io/ios/app/calculate84/id1459712793) | 4.8 (51,550) | Free | Education | | [Codecademy Go](https://appshunter.io/ios/app/codecademy-go/id1376029326) | 4.8 (37,570) | Free | Education | | [phyphox](https://appshunter.io/ios/app/phyphox/id1127319693) | 4.6 (207) | Free | Education | ## More apps by Junichi Watanabe - [WatchAfication, TimeSignal app](https://appshunter.io/ios/app/watchafication-timesignal-app/id1014493825) - [SpectralViewer, spectraView](https://appshunter.io/ios/app/spectralviewer-spectraview/id1201249094) - [PropaRuler, Measurement of radio wave propagation](https://appshunter.io/ios/app/proparuler-measurement-of-radio-wave-propagation/id1229894901) - [SoundPRuler, measurment of sound wave propagation](https://appshunter.io/ios/app/soundpruler-measurment-of-sound-wave-propagation/id1242740751) - [LastStone CurlingShotSimulator](https://appshunter.io/ios/app/laststone-curlingshotsimulator/id1355957853) All apps by Junichi Watanabe: https://appshunter.io/developer/1014493824 --- *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 2026-06-24.*