WaveTools is a suite of real-time audio analysis tools for high quality measurements: Spectrum analyzer and oscilloscope (with calibration in dB or Volts), Signal Generator (tones plus pink and white noise) and Audio Meter / Vectorscope. Although the program was written for Windows 3.1, it runs fine on XP as well. Features include:

Oscilloscope - a dual-channel storage oscilloscope
Spectrum Analyzer - a narrowband spectrum analyzer. The display shows level (Y-axis) against frequency (X-axis)
Audio Meter - provides stereo peak meters, stereo RMS (average) meters, phase correlation meter, vectroscope and peak hold.
Signal Generator - produce test tones from 20 Hz to 20 kHz plus white and pink noise. 1/3-octave band frequencies and musical notes (based on A440) can be directly selected from the menu.

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SpectraPLUS is a 32 bit Windows application that allows you to perform complex audio signal analysis without the use of any other hardware other than your Windows compatible sound card.

Record, playback and post process WAV files
Run real-time, single or dual channel analysis of live input
Five excellent displays
Dual-channel processing features (e.g),Transfer Functions
Narrowband spectrum or 1/1and 1/3 Octave scaling
Full featured signal generator

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Oscilloscope for Windows uses the sound card as an analog-to-digital
converter, providing complete oscilloscope and spectrum analyzer
functionality in Windows95 environment.

Specifications:
Dual trace digital storage oscilloscope with spectrum analyzer
20 Hz - 20 kHz bandwidth
50 ms buffer length
data export to Windows clipboard or to file (text format)

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SPADeS (Signal Processing, Analysis, Design and Simulation) combines the functionality of the earlier PC-DSP and PC-SIM applications.  It facilitates analysis, design, implementation and simulation of discrete-time signals and systems.  It can be considered as a special-purpose calculator with powerful graphing capabilities for performing digital signal processing operations such as waveform synthesis and manipulation, Fourier transforms, convolution, correlation, filter design, analysis and implementation, power spectrum analysis, and visual simulation.  It is quite simple and straightforward to use, and yet powerful and extensible enough to be used by practicing engineers as well as students of digital signal processing.

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Allows stereo sampling from :
PC Sound card or/and SPDIF I/O PC board
Wave file
Text file with various data formats
Internal test generator
External ADS hardware system (Burr Brown)

Various features :
MDI interface allows multiple opened FFT Windows
Production version supports 1'048'576 FFT data points
X-Axis linear or logarithmic
Y-Axis 1-240 dB span
Stereo FFT spectrum
Data cursor on FFT spectrum grid
Timecode information on wave and text files
History function are implemented : Average & count limit, Decay, Peak
Save/keep of FFT spectrum
FFT engine is 64 bit complex and 1024 FFT points runs on a 90 MHz

Pentium in 10 ms
Each FFT run it's harmonic data window with DR, SNR, THD, THD+N,

Noise Floor and SFDR
Special clipboard copy with custom picture size
Coherent 16/20/24 bit stereo wave generator
Dump folder tree for snapshot measurement for various data types

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