Daqarta
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:

Features:

Oscilloscope

Spectrum Analyzer

8-Channel
Signal Generator

(Absolutely FREE!)

Spectrogram

Pitch Tracker

Pitch-to-MIDI

DaqMusiq Generator
(Free Music... Forever!)

Engine Simulator

LCR Meter

Remote Operation

DC Measurements

True RMS Voltmeter

Sound Level Meter

Frequency Counter
    Period
    Event
    Spectral Event

    Temperature
    Pressure
    MHz Frequencies

Data Logger

Waveform Averager

Histogram

Post-Stimulus Time
Histogram (PSTH)

THD Meter

IMD Meter

Precision Phase Meter

Pulse Meter

Macro System

Multi-Trace Arrays

Trigger Controls

Auto-Calibration

Spectral Peak Track

Spectrum Limit Testing

Direct-to-Disk Recording

Accessibility

Applications:

Frequency response

Distortion measurement

Speech and music

Microphone calibration

Loudspeaker test

Auditory phenomena

Musical instrument tuning

Animal sound

Evoked potentials

Rotating machinery

Automotive

Product test

Contact us about
your application!

Octaves Frequency Entry Step Mode

Controls: Gen Dlg >> Stream >> Tone Freq >> Step Mode >> Octaves
Macros: Fstep, FstepOct

This mode may be selected from the Frequency Entry Step Mode dialog, which opens via the Step mode button that indicates the current mode. That button is located under many frequency entry controls in the Generator. The mode setting applies to most Generator frequency entry controls. The mode only affects values during entry or adjustment; it does not change previously-entered frequencies.

It is often useful to work with octaves rather than linear frequencies. The term "octave" derives from music theory, where a step of 8 "whole notes" (white keys on a piano, say from one C to the next higher C) represents a doubling of frequency.

The exponential nature of the human auditory system means that a change from 220 to 440 Hz, for example, sounds the same "size" as a change from 440 to 880 Hz.

Many physical systems have responses proportional to frequency or a power of frequency; a filter whose response falls proportional to 1/f will have its output voltage halved (-6 dB) for each doubling (octave) of frequency. This accounts for the common 6 dB/octave response spec of simple filters.

The Octave mode thus allows frequency changes to be made in this ratio fashion, expressed in octaves and fractions thereof. If the current frequency is 500 Hz and the Octave step size is set to 1.0000 (default), then scrolling the frequency up one step will give 1000 Hz, or scrolling down will give 250 Hz. If the step had instead been set to 0.5000 octave, the resulting frequencies would have been 707.107 and 353.553 Hz.

Octave mode allows direct entry of any arbitrary value; no quantization is applied. Only during scrolling is the octave step applied, and the result is always relative to the original value.


Macro Notes:

Fstep=Oct or Fstep=3 sets Octave Step Mode.

FstepOct=0.5 sets the step size to 0.5 octave.


See also Ratios and Octaves, Frequency Entry Step Mode, Cents Frequency Entry Step Mode, Standard Musical Note Frequencies

GO:

Questions? Comments? Contact us!

We respond to ALL inquiries, typically within 24 hrs.
INTERSTELLAR RESEARCH:
Over 30 Years of Innovative Instrumentation
© Copyright 2007 - 2017 by Interstellar Research
All rights reserved