This guide will show you how to record and visualize your voice or instrument with Overtone Analyzer. If you have no idea what to do with Overtone Analyzer, this is the place to start. It will also show you how to use the main user interface elements of the program. The quickstart guide focuses on how to use the main elements of the program, and not so much what they mean. You can find more detailed explanations of everything in the Program Reference.
Prerequisites
- You have installed Overtone Analyzer on your computer.
- You have a working microphone connected to the microphone input of your soundcard.
Configuration
Start the program. The splash screen will briefly appear, and then you should see something like this:
Here you can see the empty Timeline on the top, the Staff View and Piano on the left, and the empty Analyzer View in the main section.
Select Recording Source
Press F2 to open the Audio Settings. Here you should make sure that the Microphone is selected as your Recording Source:
Note: If you have more than one soundcard installed, or if you are using a USB powered microphone, you should first open the Device Options (F3) to ensure that the correct input device is selected.
Depending on your soundcard, you may or may not see a "Microphone Boost" checkbox. This and the recording volume require some experimentation. With a standard PC Microphone, it is probably good to check it.
Adjust the recording volume slider to be in the middle.
Now look at the box "Active Output Lines" and disable the Microphone there. This tells your computer to record the sound received by the microphone, but to not play this sound back through the speakers to prevent feedback.
Analyzer Settings
We won't worry about the Analyzer Settings for now, as the default settings that are active after installing the program should be fine to get started.
Input Level
Close the Options Dialog and look at the toolbar. On the right side of the toolbar are two sliders. The left one is the Input Level Meter. Here you can monitor and adjust the volume of the recorded sound. It is very important to adjust the Recording Volume correctly to prevent oversteering and clipping. If the input volume reaches the the red area, reduce the input level, or increase the distance to your microphone. You should aim to keep the maximum volume of the recorded sound just at the upper end of the yellow area:
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Recording Volume too low: Analyzer Display will lack detail. |
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Recording Volume too high: Analyzer will show clipping artefacts (this is worse than the volume being too low!). |
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Recording Volume optimal: Signal uses most of the available dynamic range without oversteering or clipping. Analyzer will show best amount of detail. |
Recording
Now you are ready to record some sound. Click the "Record" button on the toolbar, or press "Ctrl-Space". During the recording you should keep monitoring the Input Level and make adjustments if necessary.
Make some sounds. For example, sing the vowel 'A', and rise and lower your pitch periodically. Fill up one screen and then press "Space" to stop recording. This should look something like this:
Here you can see the intensity of the sound at the various frequency levels. The lowest thick blue stripe is the fundamental, and all stripes above are overtones. Notice how some frequencies are quite strong (such as 500 Hz - 600 Hz), while others are almost invisible (such as 1400 Hz - 2100 Hz). This is independent of the pitch of the fundamental.
Repeat this exercise with different start pitches and with different intervals. Does your voice have some frequencies that are always strong, and others that are always quiet?
Always monitor the input level. When you increase the pitch, your sound ofter becomes louder, so you may have to reduce the input volume even further to avoid oversteering.
Displayed Dynamic Range
The second slider on the toolbar controls the displayed dynamic range. This determines the amount of detail that you can see in the Analyzer View. Move this slider back and forth to see what happens. Here is the same image again, but with a larger displayed dynamic range:
Now you can even see the weaker frequency areas between 1400 Hz and 2100 Hz. You can adjust the displayed dynamic range even while you are recording. Keep experimenting with this setting to get a feeling for the structure of the sound that you are working with. You should also try this in the spectrum display mode (vs. the spectrogram display mode shown here).
Frequency Range
In the image above we looked at frequencies from 65 Hz to 4186 Hz. With most cheap microphones, you won't see much useful data below 100 Hz. But we can extend the frequency range upwards to see what is there. On the toolbar, extend the upper frequency limit to about 8000 Hz (or the note C6). Also, switch from the logarithmic to the linear frequency scale by clicking on the "lin" button on the toolbar:
Here you can see the different formants again. The area between 2500 Hz and 3000 Hz is fairly strong, and then two other regions at 5500 Hz and 6500 Hz are also standing out, although they are much weaker than the lower regions.
Experiment with different vocal techniques to see if you can influence the strong frequency areas. Try different vowels and pitches.
Navigation
Scrolling
Once you have recorded more than one screen full of data, you can scroll backwards and forwards in time by moving the displayed range slider on the Timeline with the mouse. You can also use the rewind and forward buttons on the toolbar to skip to the beginning or end of the recording, and you can press Ctrl-Left and Ctrl-Right to move the current range with the keyboard.
Time Cursor
The green line in the image below is the Time Cursor, which indicates the current position for playback and recording. During playback, you can change the current position by clicking anywhere on the Timeline or the Spectrogram. Playback will immediately continue at that point.
If you double-click on a point on the Timeline, the displayed time range will center on that point.
Zooming
You can change the duration of the displayed spectrogram by resizing the displayed range slider on the Timeline. Simply click and drag the edge of the slider:
If you need more precision, you can also enter the displayed time range on the Analyzer Settings Dialog (under Tools / Options). This has the same effect as resizing the range slider on the Timeline.
Summary
In this quickstart guide you have learned the basics of how to record and visualize sounds with Overtone Analyzer. The main steps to remember are:
- select the desired input source (such as the microphone) in the Audio Settings
- always monitor the input volume meter during recording to prevent oversteering
- adjust the displayed dynamic range to show the desired amount of detail
- navigate the recorded sound through the timeline or the keyboard
