# RT60 — Reverb decay analyzer

> Measures room reverb decay time across octave bands using pink noise. (iPhone/iPad app by Andrew Smith.)

- Source: https://appshunter.io/ios/app/rt60/id298840320 (this page in markdown: same URL + `.md`)
- Developer: [Andrew Smith](https://appshunter.io/developer/291822462)
- Category: Music
- Price: $34.99
- Rating: 3.40/5 from 5 App Store ratings · 3 written reviews indexed
- Age rating: 4+
- Requires: iOS 13.0 · 19 MB
- Languages: American English, European Spanish, German (Germany), Polish, Chinese (Simplified, China), French (France), Swedish, Japanese
- Released: 2009-03-03
- Data updated: 2026-08-14
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/rt60/id298840320/reviews.md

## What is RT60?

Now you can have an RT60 measurement tool for the iPhone. Another in the series of acoustic analysis and test applications from Studio Six Digital, RT60 measures reverb decay time for each octave band, 63Hz - 4kHz, by pulsing pink noise on and off, filtering the incoming signal by octave band, and measuring the timing of the decay of each octave band.

RT60 conforms to international acoustics standard ISO 3382
for measuring room decay time (RT) using either the T20 or T30 method.

RT60 will measure down to 50ms, and up to 4 seconds. Results are displayed for each band above the band, and the overall RT60 is calculated and displayed on the top of the screen. 

RT60 requires at least 25dB of headroom between the noise floor of the environment, and the level of the pink noise for T20 analysis. Turn up the amplifier to get more headroom.

To use RT60, connect the iPhone output to the input of an amp and speaker, and carefully turn up the level after you tap the Generator icon. RT60 smoothes the results of several readings to get a more stable result.

*** Screen Graphics

The red bars are the current SPL level for each octave band. The thin black bars show the most recently measured maximum and minimum dB levels for the octave band that the RT60 calculation is using.  The vertical yellow bars show the decay range that is available. Note that in some situations, you may not be able to overcome the ambient noise level in the room to get a good reading in every band.

*** Calculations

If a valid RT60 time can be computed, it is shown above the yellow bar. If it cannot be computed, no bar or value is shown. 

When your analysis is complete, you can save the graph image to your photo roll to include in a report.

*** Calibration & Microphone

Like all of the Studio Six Digital apps, RT60 can be calibrated. We set this field to the typical iPhone value, but if you have access to a calibrated SPL meter you can adjust this number as needed.

There is a field to select Internal or External microphone. When Internal is selected, a compensation network is used to compensate for the response of the built-in or headset mic. When External is selected, no compensation is done.

See our web site for more detailed information.

Also, check out our other great audio and acoustics apps: AudioTools, SPL, SPL Graph, for recording SPL over time, RTA, ETC, FFT, Generator, and Speaker Pop.

And, if you are looking for a great range of high-quality, professional, audio test equipment, check out iTestMic, iPrecisionMic, or liAudioInterface2.

## Key features

- Measures reverb decay time
- Octave band analysis (63Hz - 4kHz)
- Conforms to ISO 3382 standard
- T20 and T30 measurement methods
- Adjustable decay time range (50ms - 4s)
- Save measurement graphs
- Microphone calibration

## Recent user reviews (3 of 3)

All indexed reviews: https://appshunter.io/ios/app/rt60/id298840320/reviews.md

### 3/5 — ジェネレーターが・・・

*2009-05-27*

ピンクノイズジェネレーターも内蔵されて居ますが、出来ればサイトからwavでdlできると助かります。
Please up load the pink noise wav file on your web site.

### 5/5 — RT60

*2009-03-20*

As with all the other Studio Six audio apps this works just as advertised. Did a few quick measurements of a couple of professionally designed recording studios/control rooms and they came very close to the originally measured values. I just hope that Andrew can do something about attaching a better mic to the iPhone.

### 4/5 — Very gooood

*2009-03-05*

Tres bonne appli, comme toutes les autres du meme editeur ..... Simple .... Limpide .... Que dire de plus ? 4 etoiles seulement car encore des ameliorations possibles, mais l'essentiel est la. Post du 060309.

## Frequently asked questions about RT60

### What is RT60 used for?

RT60 is used to measure the reverb decay time in a room across different octave bands. This helps in understanding and analyzing the acoustic properties of spaces.

### How does RT60 measure reverb decay time?

RT60 measures reverb decay time by pulsing pink noise and filtering the incoming signal by octave band. It then measures the timing of the decay for each band.

### Does RT60 support different measurement methods?

Yes, RT60 supports both the T20 and T30 methods for measuring room decay time, conforming to the international acoustics standard ISO 3382.

### What is the range of decay times RT60 can measure?

RT60 can measure decay times ranging from a minimum of 50 milliseconds up to a maximum of 4 seconds.

### Can I save the results from RT60?

Yes, after completing an analysis, you can save the graph image to your photo roll, which is useful for including in reports.

### How accurate are the RT60 measurements?

Accuracy depends on having sufficient headroom between the noise floor and the pink noise level. The app also smooths results from several readings for stability and allows for calibration.

### What devices is RT60 compatible with?

RT60 is compatible with iPhone, iPad, and iPod devices. It requires iOS 4.3 or later.

### How often is RT60 updated?

The latest version of RT60 is 3.8, and it was last updated on December 22, 2025. Studio Six Digital typically provides regular updates for their applications.

## Version history (last 5 releases)

### 3.8 — 2025-12-22

-Bug fixes and stability improvements

### 3.7 — 2025-11-24

-Updated for new iOS devices
-Bug fixes and stability improvements

### 3.6 — 2024-11-20

-Updated for latest iOS devices and calibrations
-Bug fixes and operational improvements

### 3.4 — 2024-07-10

-Updated for latest iOS devices and calibrations
-Bug fixes and operational improvements

### 3.3 — 2022-07-13

-Bug fixes and improvements
-Support for more iOS devices and iOS versions

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## More apps by Andrew Smith

- [Speaker Polarity](https://appshunter.io/ios/app/speaker-polarity/id293263027)
- [SPL](https://appshunter.io/ios/app/spl/id293573990)
- [RTA](https://appshunter.io/ios/app/rta/id298839433)
- [FFT](https://appshunter.io/ios/app/fft/id298840058)
- [Generator](https://appshunter.io/ios/app/generator/id298840802)

All apps by Andrew Smith: https://appshunter.io/developer/291822462

## Related topics

[reverb room rt60](https://appshunter.io/ios/topics/reverb-room-rt60)

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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 2026-08-14.*