Help & FAQ
Frequently Asked Questions
Find answers to common questions about using Voqales.
How long can I record for?
Up to 30 seconds per recording. For vowel analysis you rarely need more than a few seconds — a sustained vowel for 2–3 seconds gives the analyzer plenty of material to work with.
Do I need to say a specific word?
For the vowel space chart, sustained vowel sounds work best — hold a single vowel sound for 2–3 seconds rather than speaking full words or sentences. For the spectrogram, natural speech is fine and often more interesting to explore.
How close should I hold the phone?
Really close.
Why does my recording show very few or no formant dots?
A few possible causes. First, check that you are actually producing voiced sounds — whispering, for example, produces no formants. Second, the voice threshold setting may be too high for your recording level; try lowering it from 0.03 to 0.01. Third, if there is a lot of background noise the analyzer may be rejecting frames — try recording somewhere quieter.
Why do the formant dots jump around erratically?
Some variation is normal, especially at the start and end of a sound. If it seems excessive, try increasing the Smoothing setting (0.4 to 0.6) or the LPC Window from 45ms to 55ms. Both reduce jitter at the cost of some temporal precision.
What do the selection handles do?
Dragging the left and right handles narrows the time range that is used for the vowel space chart and the readout strip at the top. This lets you isolate a specific moment — for example, the steady middle portion of a vowel — and exclude transitions at the start and end.
The spectrogram looks very washed out or very dark. How do I fix it?
Use the Contrast setting in the Color & Overlays panel. High contrast makes quiet detail more visible; Low contrast is better if the image looks blown out. If the colour scheme itself is the issue, Heatmap and Monochrome are better in bright lighting conditions.
Can I export the spectrogram as an image?
Not in the current version. You can use iOS's built-in screenshot function (side button + volume up) to capture it.
The Play button does not produce any sound.
Another app may have the audio session. Try closing other audio apps and tapping play again. Also check that your phone is not in silent mode.
The app asked for microphone permission and I accidentally denied it.
Go to Settings → Privacy & Security → Microphone, find Voqales, and enable it. The app cannot record without this permission.