# MiscEl: Waveforms

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This page is used to view different waveforms, do calculations on them and listen to them. Many different waveforms can be generated, some are predefined, but selecting a "user" waveform opens another page where waveforms can be generated form harmonics, tabular data or formula.

### Predefined curves

• Sinus, ordinary sinus
• Triangle, symmetric or asymmetric triangle
• Sawtooth /, rising from low value
• Sawtooth \, falling from high value
• Square, symmetric of asymmetric square wave
• Clip sinus, sinus with top and bottom clipped
• Clip sinus U, sinus with top and bottom clipped, amplitude is specified for unclipped sinus
• Clip triangle, triangle with top and bottom clipped
• Clip triangle U, triangle with top and bottom clipped, amplitude is specified for unclipped triangle
• Square rise/fall, square with triangular rise and fall times
• User, use "Waveforms user curve" to define waveform
• Other, get value from other part of miscel program (function is not used yet)

### Input values

 Rectify Use the positive (single+), negative (single-) part of the curve,(full) will use the absolut value of the curve Chop Chop first/last/both part of a curve, use to simulate triac control (This function does not handle offset) Vpp & Vofs Specify the curve amplitude as peek-peek voltage and a offset Vmax/Vmin Specify the curve amplitude as max and min voltage Frequence Specify frequence for curve, this will not change the curve, but will affect the scale and filter calculations High Percent Defines duty cycle Time/Time 1/Time 2 Specify frequence as periode time, either total or for high/low part of curve Chop pct. Defines ammount of curve to chop (start-end), value is in percent of total curve Clip pct. Defines ammount of curve to clip (top-bottom), value is in percent of total curve Filter See below Filter Fo Center frequence for selected filter FFT Show a Fast Fournier Transformation for the curve Play Use the soundcard to play the waveform, voltage and offset are ignored. MiscEl restrict the output frequence to 10 Hz to 65 kHz and 16 bits. The soundcard will probally restrict the range further

### Predefined Filters

• None, no filter is applied to waveform
• 20 dB/dec ideal LP, this filter will reduce each harmonic without changing the fase, it can not be made in real life
• 20 dB/dec RC LP, a standard low pass filter, as can be made with a resistor, capacitor combination
• 20 dB/dec RC HP, a standard high pass filter, as can be made with a resistor, capacitor combination
• Butterworth LP 2., a low pass filter with butterworth response
• Butterworth HP 2., a high pass filter with butterworth response
• Only Fo, remove all frequences, except Fo. This will leave a sinus at Fo (if Fo exist as a harmonic)
• Remove Fo, Fo is removed from the harmonics.
• Remove below Fo, all frequences below Fo is removed from the harmonics.
• Remove above Fo, all frequences above Fo is removed from the harmonics.
• Remove even harmonic, all even harmonics are removed (curve will always be symmetric after this filter)
• Remove odd harmonic, all odd harmonics are removed (symmetric curves will be completly removed)
• RIAA, process the curve with the RIAA filter
• Other, use some other part of miscel to do the filtering, this function must be enabled from the other page

### Output values

All output values are calculated from the shown waveform.
 Frequence Frequence and periode time DC voltage Calculated DC, this is also shown as a blue line Mean voltage The mean voltage, if the waveform was rectified, this is also shown as a red line RMS voltage RMS (Heat) value of waveform, this is also show as a yellow line Peek-peek voltage Difference between highest and lowest voltage in waveform Form factor An expression that express the differens between RMS and average voltage Crest factor An expression that express the differens between peek and RMS voltage. All RMS meters has a max. Crest factor. Max. slew rate How fast the voltage is changing Rdg. on avg. meter This value is about (Mean voltage)*1.1, and is the value a non RMS meter will show for this waveform 0 dB Reference use for FFT display DC voltage DC component from FFT n×Fo Harmonic n and its value (relative, dB, voltage, phase), up to 10 harmonics can be shown

### Hints

• It is not possible to specify a RMS or mean amplitude for a curve, but using ctrl-n and ctrl-m it is fast to adjust Vpp, until a specified RMS voltage is reaced (Use "System, Prefered components" to adjust stepsize).
• Clicking on the curve will measure values
• To see the actuel value of higher harmonics, click and drag on the harmonic display
• The rectify function is a mathematical function and does not simulate a diode
• The play function is using a very high level (for best precision), this may damage loudspeakers.
• To pass the waveforms through a filter use the 1. order filters page

### Other pages

• For calculation on sound in air, use the Sound page.
• For calculating filters, use the 1. order filters page.