RoomScope and IOScope measure longer IRs and use 64-bit FFTs


RoomScope 1.2 and IOScope 2.3 arrived in the iOS App Store this week. Both apps now support impulse response measurements up to 16 seconds long and use double precision (64-bit) FFTs in their measurements. The maximum measurement length is dependent on the amount of memory available on the device, so 16-second measurements are currently only supported on the iPhone 5, iPad 3, and iPad 4. The previous generation of devices, including the iPod touch 5, supports 10-second measurements, and older devices are still limited to measurement durations of 5 seconds or less.

RoomScope 1.2 also offers the following additions:

  • Center time has been added to the list of calculated acoustic parameters.
  • All parameters are now calculated in low, mid, and high frequency bands, as defined by the ISO 3382 standard.
  • The calculation of the clarity and definition parameters (C and D) compensates for the delay of the whole and 1/3-octave band filters, as described in ISO 3382.
  • Raw IR data can now be excluded or included in CSV, MAT, and TXT file data exports.

RoomScope turns your iPad, iPhone, or iPod touch into a room acoustics measurement and analysis tool. With RoomScope, you can measure a room impulse response and then calculate reverberation time, early decay time, center time, clarity, and definition, as defined in the ISO 3382 standard. RoomScope also allows you to adjust the Schroeder decay curve integration limits with the touch of your finger and plot the calculated room parameters versus whole or 1/3-octave band center frequency.



Download RoomScope 1.2

IOScope brings true dual-channel transfer function and impulse response analysis to iOS. With IOScope, measure loudspeaker impedance, frequency response, and sensitivity. Measure a room impulse response. Tune a large sound reinforcement system, time-align a set of surround sound speakers, or optimize your home stereo. Determine the actual cutoff frequencies of your latest speaker crossover circuit, or teach your students the fundamentals of Fourier analysis of dynamic systems.

Measure frequency response magnitude and phase, coherence, and group delay. Time domain functions enable you to measure impulse response and auto/cross-correlation. IOScope includes a built-in signal generator for producing suitable excitation signals to analyze your system or device under test (DUT). See for a video demo of loudspeaker impedance measurement.


Download IOScope 2.3



  • Boris

    Hi guys, RoomScope looks great – but i am not able to get consisten data out of it. It would be very helpful to get a step by step instruction how to do a first measurement. Would that be possible?

  • Berthold

    Wow, roomscope seems to be a really nice measuring instrument. Especially the measuring of the impulse response is very helpfull. Does the software compensate the microphone of an IPhone or IPad which isn’t construed to this application?

    • ben

      RoomScope does not attempt to compensate for non-uniform microphone frequency response. If you want to make higher quality measurements, then an external measurement microphone is recommended. You might want to take a look at the MicW i436 for a low-cost measurement microphone.

  • Okay, thanks for that advice, but I already got some measuring equipment. I think the measurements with IPad IPhone can be a very good first approach and be done very easily wihtout lots of knowledge.

    • ben

      For what it’s worth, the electret microphones built into iOS devices typically exhibit a fairly flat response across the audio frequency band.