Data AcQuisition And Real-Time AnalysisScope - Spectrum - Spectrogram - Signal Generator
Software for Windows
Science with your Sound Card!
Sound Card Pitch Tracker
The above image shows the Daqarta Pitch Track Toolbox feature as it tracks a whistled version of "Deck The Halls". The approximate locations of the corresponding words are shown at the bottom of the Notes Edit area below the trace.
(See Getting Started With Pitch Track for a step-by-step discussion of the full setup details.)
Pitch is shown as vertical position on a "piano keyboard" background. The displayed range is from about 1000 to 2500 Hz (984.375 to 2484.375), as set via the Expand and Min and Max controls near the top of the dialog at the right.
Loudness is shown as color, using the current Spectrogram color scale along the right side of the trace area. PgUp and PgDn expand or compress the dB range shown, and SHIFT with these slides the range up and down. The Colors button at the top of the dialog allows you to change the palette used for the color scale, and also the colors of the white and black background keys.
The Track Limits button opens a dialog that includes the Track Threshold control. In this example, it has been set to -62 dB, which is a medium blue. Input signals lower than this are not shown; they are mostly breath noise. But the actual whistled notes are much louder than the threshold, in the range of -10 to -20 dB (yellow). Thus, at note transitions there are a few stray light blue and green pixels which could have been suppressed by setting the threshold higher.
The Track Limits dialog also has controls to limit the range of frequencies that will be considered as possible pitches, to reduce spurious responses from out-of-range signals. Here, the range is limited to about 500-2500 Hz. (Note that it does not need to match the displayed range.)
Below these, the Wide button is unselected. Had it been active, the pitch would have been shown with a fatter line. That would make it easier to see at a distance, but harder to resolve fine pitch deviations and vibrato.
The button next to that is marked Notes, and controls the labels on the vertical axis. Clicking it causes it to step through Freq and MIDI options, which would label the same axis points in hertz or MIDI note number. The Freq option is handy for setting display and pitch track ranges, and the MIDI setting may be used for adjusting controls in the Pitch-to-MIDI dialog.
The Steps button is unselected, so the pitch trace indicates the actual instantaneous pitch frequency even when it is sharper or flatter than a standard note. When Steps is active, the incoming pitch is quantized to show only the nearest standard note, just as it would be presented to the Pitch-to-MIDI converter (if active). In that case, the pitch trace would "step" from the center of one note to another. This process allows the Hysteresis control to make notes "sticky", such as to prevent the Pitch-to-MIDI converter from jumping back and forth when vibrato crosses a note boundary.
The Pitch-to-MIDI button opens a dialog that allows you to convert your whistled tune into a multi-instrument MIDI performance. But be advised that you will almost certainly need to install a different synthesizer than the default Microsoft Wavetable GS that comes with Windows, since it has excessive note lag (over 100 msec). See Getting Started With Pitch-to-MIDI for more details about the problem, and MIDI Device Select for some inexpensive or free replacement options.
On the other hand, the Wavetable GS is perfectly fine for KaleidoSynth and DaqMusiq use.
Please note: The present Pitch Track system does not work well with low frequencies, especially male voices. A special low-frequency tracking enhancement is planned for an upcoming Daqarta version. You can be notified of new releases via Email by checking the box on the Daqarta Contact Form .
Contact us about
Questions? Comments? Contact us!We respond to ALL inquiries, typically within 24 hrs.
Over 35 Years of Innovative Instrumentation
© Copyright 2007 - 2021 by Interstellar Research
All rights reserved