Soundbeam 4+

This is a delightful app that functions as an oscilloscope for audio frequencies. I used an audio frequency generator (Function Generator Pro) on one device and plugged it into my iPhone via an audio cable and was able to view sine, square and triangle waveforms as if I were using an actual physical oscilloscope. I also built an electronic circuit to generate a sine wave and fed it into my iPhone via a Scarlett audio interface and that also worked wonderfully, showing the sine wave and frequency! The iPhone has a high-pass filter that cuts off anything over 10KHz, but for my projects that frequency was plenty high enough.

Running an audio app and Soundbeam on my iPhone simultaneously showed me the waveform and the FFT-style spectrum analysis—the audio came out the speaker and back in via the microphone. What a great and inexpensive way to help understand how sound waves work!

Enhancement request: let me zoom in horizontally while in waveform mode, and display the time scale.

100% great! I love this application I use it to monitor modulation characteristics on my Ham radio with the external microphone input. The graphics are really good kinda hard to tell your not looking at a dedicated scope, in spectrum mode you can clearly see band pass filter roll off. I would like to be able to vary the time base in scope mode perhaps in another version or update you do have the option of adjusting the vertical gain in scope mode and selecting linear or logarithmic display in spectral mode. Truly a five star development 73 de KF6FOK

Very powerful and robust little app! A fascinating, teaching aid for both technical and non-Technical applications! Extremely interesting!!!