Data AcQuisition And Real-Time Analysis
Scope - Spectrum - Spectrogram - Signal Generator
Software for Windows
Science with your Sound Card!
The following is from the Daqarta Help system:



Spectrum Analyzer

Signal Generator

(Absolutely FREE!)


Pitch Tracker


DaqMusiq Generator
(Free Music... Forever!)

Engine Simulator

LCR Meter

Remote Operation

DC Measurements

True RMS Voltmeter

Sound Level Meter

Frequency Counter
    Spectral Event

    MHz Frequencies

Data Logger

Waveform Averager


Post-Stimulus Time
Histogram (PSTH)

THD Meter

IMD Meter

Precision Phase Meter

Pulse Meter

Macro System

Multi-Trace Arrays

Trigger Controls


Spectral Peak Track

Spectrum Limit Testing

Direct-to-Disk Recording



Frequency response

Distortion measurement

Speech and music

Microphone calibration

Loudspeaker test

Auditory phenomena

Musical instrument tuning

Animal sound

Evoked potentials

Rotating machinery


Product test

Contact us about
your application!

!Spooky4.DQM MIDI Setup for Halloween

This setup was created as background sound for a Halloween display. The original plan was to use the Daqarta Generator to produce the "oooo EEEE oooo oooo" theremin theme used by old science fiction movies for creepy scenes. That plan resulted in the !Spooky.GEN setup, which allows the smooth glides between notes that are a feature the theremin. It provides a good reproduction, and also allows numerous modifications.

However, continuous repetition of the same four-note theme all evening is not conducive to a happy Halloween for the person handing out the treats. This MIDI-based version solves that problem by playing the same theme, but with four random instruments at a time, in different octaves, changing everything after only two repetitions. The variations keep everyone happy all night long.

One theremin feature that !Spooky4 does not retain is the smooth note transitions, because the Windows built-in Microsoft GS Wavetable Software Synthesizer doesn't support portamento commands.

Here's the MIDI setup dialog for Voice 1. The other 3 voices are identical except for the Changes scripts:

The Voice 1 Changes script is:

GPS=2                   ;Pitch Display = Show MIDI Note / Inst
{!                      ;Infinite loop
I1=?(0,119)             ;Random instrument I1 between 0 and 119
n1=?(-2,+2)*12          ;Random Note shift between -2 and +2 octaves
W=8                     ;Wait for 8 beats
}                       ;End infinite loop

The GPS=2 command to set the pitch display mode only runs once, then an infinite loop runs until you stop the performance manually.

Voices 2 through 4 have only the inner part of the above loop, differing only in the voice number for instrument I and note shift (b n. Here is Voice 2:

I2=?(0,119)             ;Random instrument I1 between 0 and 119
n2=?(-2,+2)*12          ;Random Note shift between -2 and +2 octaves
W=8                     ;Wait for 8 beats

Multiple computers were used in the Halloween display. One showed the MIDI notes and instruments as created by !Spooky4.

A second computer was connected to a microphone that picked up sounds from the front porch, including the !Spooky4 music as well as kiddie voices. These sounds were displayed as a continuous spectrogram on a large-screen TV used as a monitor via HDMI. The monitors were part of a "mad scientist lab" display arranged in a large bay window, with a headless body on the operating table and several prospective heads nearby.

A third computer created background "power hum" with the Daqarta Generator running the Machines.GEN setup. This created sound on the Left channel that rose and fell on a 10-second cycle. It also created a special signal on the Right channel that controlled the room lighting, such that it flickered and dimmed when the machine noise was at its maximum, to simulate equipment drawing too much power.

See also !Spooky.GEN Theremin Simulator, Machines.GEN Mad Scientist Lab Background Sound, Example MIDI Setup Files, MIDI Setup Files, Musical Frontiers, DaqMusiq, KaleidoSynth, Pitch-to-MIDI dialog, Pitch Track Toolbox - Overview, Spectrogram / Pitch Track Controls, Spectrogram / Pitch Track (Sgram/PT)


Questions? Comments? Contact us!

We respond to ALL inquiries, typically within 24 hrs.
Over 35 Years of Innovative Instrumentation
© Copyright 2007 - 2023 by Interstellar Research
All rights reserved