Here is a list of best free audio spectrum analyzer software for Windows. These spectrum analyzer software let you visualize audio spectrum for real-time signals. In some of these audio analyzer software, you can analyze amplitude and phase spectrum as well. Also, you can visualize audio spectrum in FFT spectrum, 2D spectrogram, Octave spectrum, etc. modes. Moreover, they let you specify frequency range, amplitude range, and many other audio parameters to analyze the defined range of audio signals.
Real-Time Audio Spectrum Analyzer Software
With the help of some of these software, you can have information about the instantaneous frequency, mean value, crest factor, form factor, RMS voltage, audio intensity, etc. Most of these audio spectrum analyzers also provide oscilloscope view of audio signals. These also facilitate you with a signal generator. Generally, the signal generator helps to generate sine wave, sweep wave, white noise, pink noise, etc. signals with specified frequency.
Visual Analyzer is one of my favorite audio spectrum analyzer software. From the left part of its interface, you can have general information about audio parameters like frequency, mean value, peak, peak to peak, etc. Also, it comes with a variety of FIR and IIR filters to apply them to input audio signals.
Visual Analyzer is a free audio spectrum analyzer software for Windows. This software lets you analyze real-time phase spectrum of audio signals given through input audio devices. To do so, it provides multiple options to adjust step size (in dB), specify value considered as 0 dB, frequency range, distortion, etc. Also, it lets you specify octave band analysis (1/1, 1/6, 1/24, etc.) and customize spectrum by using given music presets (piano, flute, guitar, etc.). After setting up all these configuration options, you can save configuration settings, or use Save as option to store these settings as INI files.
Apart from audio spectrum analysis, it lets you apply separate filters (various FIR and IIR filters) to individual audio channels, analyze audio using Frequency meter, period meter, and voltmeter, etc. It also lets you calibrate left and right audio channels using built-in measure signals.
AUDio MEasurement System is a free and open source audio analyzer software for Windows. It lets you analyze the performance of sound card of your PC. You need to specify input and output devices to analyze them prior to initiating analysis process. There are four analysis options available in this software, which are Generator, Oscilloscope, Spectrum Analyzer, and Frequency Response.
Spectrum analyzer lets you analyze db vs Hz plot of input audio signal spectrum in real-time. All you need to do is, enter the number of sample in the specified field and click on Start button. Now, you can graphically analyze audio spectrum in real time.
Friture is another good audio spectrum analyzer software for Windows. It lets you plot multiple graphs in order to perform audio spectrum analysis. You can plot FFT spectrum, Octave spectrum, 2D spectrogram, etc. and manage their corresponding settings for real-time audio spectrum analysis. For FFT spectrum analysis, you can set maximum and minimum frequency, FFT size, Min and Max amplitude in dB, etc. parameters to perform audio analysis for single channel or dual channel input. Also, you can change frequency scaling mode to linear or logarithmic mode. In Octave Spectrum analysis, you get options to change settings like Bands per octave, min and max amplitude (in dB), response time, etc. For 2D spectrogram analysis, you can set time range (in sec.), min and max color, frequency scale, etc.
One of the distinguishing features of this audio analysis software is that it supports multi-dock view i.e. you can add new docks to the interface to analyze different spectral views at the same time.
Frequency Analyzer is another free audio spectrum analyzer software for Windows. It is a simple and easy to use software with minimal options available at its interface. Like other software, it also generates frequency spectrum in real time. For that purpose, you need to either connect a microphone or provide input as WAV or Bitmap file.
From the bar given at the bottom of the interface, you can analyze maximum instantaneous frequency (in Hz), audio intensity (in dB), rms voltage (Vrms), etc. for audio signals. By using this audio spectrum viewer software, you can print a graph of the plotted spectrum.
TrueRTA is a free audio analyzer software for Windows. Using this software, you can easily check out audio input and output devices connected to your system. If you have connected a microphone, then you can start speaking through it and corresponding signal fluctuation will be shown on the display. Also, it facilitates you with a signal generator, oscilloscope, and spectrum analyzer. From the right side of the interface, you can set dB limit (from -160 dBu to 20 dBu), and frequency limit (10 Hz to 50KHz) to provide sufficient dynamic range for signal fluctuation. Thus, lets you perform audio spectrum analysis in a better way.
In the free version of this audio spectrum analyzer, the Spectrum analyzer option provides only 1 octave real time analyzer mode. You can update to its other versions to get more options.
Oscilloscope (Winscope) is an excellent real-time audio spectrum analyzer software for Windows. It comes with an FFT spectrum analyzer and operates in two different modes for spectrum analysis: YT Single Trace Mode and YT Dual Trace Mode. Using single trace mode, you can get only amplitude spectrum of real-time signal, while dual trace mode lets you analyze both amplitude and phase spectrum.
Friture helps you to understand audio data with several widgets:spectrum analyzer
rolling 2D spectrogram
fraction-of-octave analyzer
delay estimator
etc.
With spectrum analyzer, engineers visualize, measure, and analyze the frequency domain characteristic of evolving multichannel signals or streaming data in real-time during simulation in MATLAB or Simulink.
The spectrum analyzer software computes and displays the spectrum, power-density spectrum, and spectrogram for variety of signals and data types, including audio, biosignals, communication signals, speech, and streaming data. The user interface, features, and measurements are consistent with conventional hardware-based spectrum analyzers.
Spectrum analyzer software in DSP System Toolbox showing visualization and measurements for analyzing signals and streaming data (starting clockwise from top left) harmonic distortion; spectrogram view with cursor measurements; adjacent channel power ratio (ACPR); third order intermodulation distortion (TOI).
See also:DSP System Toolbox, LTE Toolbox, Communications Toolbox, Phased Array System Toolbox, Signal Processing Toolbox, HDL Coder, Embedded Coder, Simulink Coder, Fixed-Point Designer, RF Blockset, RF Toolbox, stream processing in MATLAB, logic analyzer, parametric equalizer, audio signal processing, oscilloscope software, Why Simulink for Wireless System Design
This program started as a simple FFT program running under DOS a long timeago, but it is now a specialized audio analyzer, filter, frequency converter,hum filter, data logger etc (see history). You can download it from this site. Or look into the manual (in HTML format), even though the manual included in the archive will be more up-to-date. Furthermore, the same manual has occasionallybeen converted into a single PDF (SpecLab_Manual.pdf), but any attemptto create a common index and table of contents for this PDF, using OpenOffice (with proper page numbers instead of the hyperlinks)has failed miserably - see note in the preface of the PDF document.If you are looking for a short description in German language, look here. The revision history is here. How to use SpecLab with SDR-IQ is described here;how to use SpecLab with PERSEUS (without an annoying virtual audio cable)is here,and how to use SpecLab with software-defined radios supporting ExtIO (instead of a soundcard),like FiFi-SDR, RTL-SDR, FunCube, SDRplay RSP, etc etc, is described here.If you need help getting the program running, or have questions about aparticular function, look into theSpectrum Lab User'sforum at groups.io (not at Yahoo anymore).. (SpecLab screenshot in "Colour Direction Finder" mode, VLF spectrum,colourbearing)Spectrum Lab runs under Windows 98 to Windows 10 (not sure about laterversions of Windows, since the author won't use them), and Linux/WINE.Features Input can be taken from the soundcard, but the "audio utility" interface makes it possible to create an interface to any A/D converter you like (for example a PIC with serial interface). A plugin for Winamp allows to analyse audio streams from the internet (see download section). Besides the soundcard and the interfaces supported by the "audio utilities", SpecLab directly supports SDR-IQ and SDR-14 (by RFSpace, Inc), and PERSEUS (by Microtelecom s.r.l.). Demodulated output is usually sent to the soundcard, but can be sent anywhere else (including an MP3- or OggVorbis encoded stream using Winamp/Oddcast and a special Audio-I/O DLL, which acts as an input plugin for Winamp). Selectable and adjustable waterfall color palette allows you to change the contrast of the waterfall display during and after receiving spectrum lines ("contrast" & "brightness" - sliders) Frequency range can be adjusted while running, the old part of the waterfall display will automatically be re-drawn without stopping the audio processing. Special waterfall mode for "Radio Direction Finder" with colour-coded azimuth display, based on DF6NM's Wideband Direction Finder with Colour Encoded Spectrogram Display. Now with up to three "notches" (adjustable nulls in the synthesized antenna pattern) to suppress noise from certain directions. Special "multi-strip" waterfall mode for long term observation of relatively narrow bands Reassigned spectrogram for higher time- and frequency resolution, if certain conditions are fulfilled (since 2009-06) Support for image-cancelling direct conversion receivers ( quadrature input via stereo soundcard ) Very sharp, FFT-based audio filters which can also be used to shift and invert frequencies, with auto notch, denoiser, etc. New (2007-02): Write your own plugin for the FFT filter ! Waterfall display may run from top to bottom, or from right to left (good for HELL modes) Calculation of peak levels, peak frequencies, noise levels, effective values, SINAD, etc File logging and file analysis with WAVE files ( now with 'Triggered Audio Recorder' + pre-trigger option ) Periodic or scheduled actions, for example to capture the screen as BMP or JPEG file Audio sample rates from 8000 to 192000 samples per second. 192 kS/second only tested with a few cards, using ASIO drivers and / or standard multimedia driver. With extra hardware (like software-defined receivers with high-speed USB interfaces), even higher sampling rates (and thus bandwidths) are possible. 16-bit ADC resolution giving about 90dB of input range (plus additional FFT gain!) 24-bit resolution possible with certain cards (tested with Audigy 2 ZS; 2004-05) Frequency resolution in the sub-milliHertz range (exceeding the stability of the soundcard's clock generator). FFT output is buffered in an array with adjustable size for long-term observations (with "scroll-back-in-time" while analysis continues). Furthermore, the FFT output can be recorded (exported) in various formats. Signal generators with selectable waveform, frequency, and optional modulation, plus noise generator Hum filter to remove 50 Hz (or 60 Hz) plus harmonics, based on Paul Nicholson's algorithm for a multi-stage comb filter with automatic tracking. If you are interested in improving your Natural Radio reception, read Paul's Notes on Domestic VLF Reception. Frequency converter to shift low "IF"-frequencies (e.g. 17.2 kHz) to audible tones (650 Hz, etc) in real-time. Can be used in a 'soft-VLF-RX'. Other demodulators in DSP-blackbox. Decoder for some time-code transmitters: MSF(60kHz), HBG(75kHz), DCF77 (77.5kHz) can now be used to set your PC clock to a high accuracy. All you need is your longwave receiver and the soundcard. Modulator and decoder for some 'experimental' digital communication modes like PSK31, BPSK, QPSK, FSK, multi-tone HELL, MSK (minimum shift keying since 2004-12), transmission and reception of letters with a small 'terminal' window. A DLL interface is available to use Spectrum Lab for new digital transmission modes (but not in use yet). Fast waterfall with up to 200 waterfall lines per second, making it possible to decode even fast Morse code by eye (though it wasn't intended for that, it's fun to watch) versatile export function (text-file based, for post-processing with Excel etc.). Brian, CT1DRP has used the export functions to create spectrograms and signal graphs of the 136kHz band. Built-in HTTP server so you can write a (simple) user interface for SpecLab in HTML (intended to be used in a LAN, not as a fully-fledged web server). Communication with other applications through a simple message-based system, which is also used by SpecLab to communicate with the RDF calculator (range-and-bearing calculator + map plotter, link may work on the main site only).(screenshot of "Components" window from an older version)Features which this analyzer does not have (but others do...): Due to its 'Laboratory' nature, this analyzer is not as easy to use as ARGO (by I2PHD and IK2CZL, available on Alberto's homepage: www.weaksignals.com ). Some Applications AMSAT-DL's Earth-Venus-Earth experiment on 2.4 GHz at the Bochum radio telescopeIn March 2009, a group of radio amateurs successfully bounced a radio signaloff Venus, over a distance of (2*) 45 million kilometers. A short descriptionof the reception technique (software) can be foundhere; more details are on theAMSAT-DL website, and in the AMSATjournal soon. Thanks to DD5ER, DJ1CR, DJ4ZC, DH2VA, DK8CI, DL1YDD, G3RUH,ON6UG, and everyone else who contributed, for being part of the team. The configuration used for the (2.4 GHz) EVE test is part of the installationpackage now (EVE-SDR-IQ-5kHz_2G4.usr); we used the SDR-IQ for this. If youwant to try something similar and have a PERSEUS receiver, useEVE-Perseus_2G4.usr instead. Beacon Logger for DI2AG (July 2005)How to use Spectrum Lab to produce field strength plots of DI2AG, an experimentalmedium wave beacon on 440 kHz in southern Germany. It realizes some ideaswe spoke about at the Ham Radio fair in Friedrichshafen (June 2005). Moreinfo in this document (up to now, in german language only) :Beschreibung des Einsatzes von SpectrumLab als Bakenlogger für DI2AG. Update 2007: DI2AG has moved to 505kHz now (which is a new amateur radio band in many countries - with the exceptionof Germany..). Hellschreiber Modes in Spectrum Lab (Nov. 2004)There is a special narrow-band transmission mode in Spectrum Lab's "digimodeterminal" called Chirped Hell, based on an idea by Markus, DF6NM. We usedit on the amateur longwave band (136 kHz) to make some narrow band transmission.A special property of Markus' Chirped Hell principle is the relatively lowcrest factor, so it can be used to transmit characters (and even small images)quite effectively, but (unlike sequential multi-tone hell) you need a lineartransmitter. An image received on a waterfall in "QRSS 3" mode may look likethis: LowFER Receiver Using a "Software" IFThis article by LyleKoehler, KØLR, describes a simple "software defined" receiverand some other (easier-to-use) alternatives to SpecLab too. Don't miss Lyle'sdownconversion circuits which he sucessfully uses to the receive US-AmericanLowFER beacons. The last part describes how to log fieldstrengths of LowFERbeacons with Spectrum Lab's plot window. G7IZU Radio Reflection Detection PageThis nice website by Andy G7IZUmonitors Meteor Shower, Aurora Sporadic-E and Solar Flares in real time,mostly using reflections of radio signals in the 50 MHz region. VE2AZX precise frequency measurementsJacques, VE2AZX, describeshere how SpectrumLab can be used for precise frequency measurements in the millihertz region.Don't miss his detailed description - it's actually better than SpecLab'sbuilt-in help system ;-) Bat ConverterIf you have a suitable soundcard, you can use SpecLab to make ultrasonicbat calls visible and audible in real-time. In the menu, select "QuickSettings".."Natural Radio / Animal Voices" .. "Bat Converter". This configurationrequires a soundcard with true 96 kHz sampling rate, and a PC with at least1.7 GHz. The software shows the call in a fast spectrogram (with high timeresolution, but little frequency resolution), and converts the ultrasounddown to audio, notches out constant-frequency "carriers" (like your CRT monitor'sline sync frequency, which is annoying if it's in the "bat band"), and finallypasses the downconverted and filtered signal through an automatic gain controlstage.As a test, I used a cheap miniature electret microphone to makethis recording of bat sounds(96 kHz, 16 bit, mono .. right-click to save it). If you play it with a normalaudio player, you will hardly hear anything. But if you play it into SpecLab(menu "File".."Audio Files".."Analyze and Play", with the "Bat Converter"setting loaded, you will hear the bat calls. I don't know which species itis yet, but they seem to be quite frequent in this part of Germany. FFT Filter PluginsThe FFT-based filter in Spectrum Lab is already very versatile, but it canstill be extended with a "filter plugin". These plugins come in the formof a special windows DLL which can be loaded from the filter control panel.Such plugins can be written with any C / C++ Compiler (recommended: BorlandC++Builder V4 or DevCpp V4.9.9.2; the latter is a free development systembased on the GNU / MinGW compiler). To develop your own plugin, downloadthis FFTFilter Plugin package - it contains all required information requiredto write a filter plugin, and a sample plugin written in the "C" programminglanguage. NOTE: THE DLL INTERFACE IS STILL "SUBJECT TO CHANGE" ! Download Spectrum Lab..To check if you have the latest version of Spectrum Lab, compare the textin the main window's title bar with the revision number and compilation dateat the top of this document. For example, if you have "Spectrum LaboratoryV2.2 b1", it is way too old. If you have SL already installed, you can checkif it's up-to-date by selecting Help .. Check for Updatein the main menu. The primary download site for Spectrum Lab is here: Primary: www.qsl.net/dl4yhf/speclab/install_speclab.zip, (V2.95 b3, compiled 2020-10-03 or later, with new output switches, a bugfix in the noiseblanker, Ogg/Vorbis audio file reader and -writer, wave files with 24-bit integer and 32-bit floating point samples, GPS (NMEA) decoder also through the soundcard, input resampler optionally using the GPS PPS output for synchronisation, support for Winrad-compatible ExtIO-DLLs (also for FiFi-SDR), new controls for the filter passbands on the main frequency scale... see revision history. The latest additions were: OpenWebRX-alike server for remote live audio and waterfall in a web browser (details here) Extended CAT/CI-V protocol to display broadband spectra from an IC-7300, IC-7610, IC-7851, etc(?) Forwarding of CI-V messages from and to multiple clients (e.g. WSJT-X, RS-BA1) on extra serial ports Timestamped event queue for the Conditional Actions Non-differential encoding for experimental (B)PSK transmissions New sample formats received over the serial port (e.g. from the GPSDO currently under development) Modified the reader for non-compressed, timestamped web streams (and their logfiles; *.dat) Modified triggered audio recorder Modified COM port enumeration because a stupid Bluetooth driver blocked the application for many seconds Spectrum buffer can be retrieved as JSON object via SL's integrated web server Different buffer sizes for audio processing and soundcard I/O Modified Audio-I/O DLL interface (bugfix in the configuration dialog) Support for RTL-SDR (via ExtIO-DLL) Improved speed, at the expense of compatibility with ancient 80486 EbNaut-recorder configuration files Compressed Ogg/Vorbis file selectable for recording audio (besides non-compressed Wave audio) Backup: _speclab.zip. Installer-less ZIP: www.qsl.net/dl4yhf/speclab/SpectrumLab_without_Installer.zip. 'BETA': www.qsl.net/dl4yhf/speclab/install_speclab_beta_2023_02_05.zip (This is seriously 'under construction', and is really "only for beta testing" yet..): Contains all the above, plus some new (unstable) features which are not required for 'normal' use: Up to 40 simultaneously running instances (if you have plenty of RAM; not tested yet), Automatic closing of audio devices shortly before system suspend ("PC sleeping"), and automatic re-opening after resume ("wakeup from sleep"), and a tiny subset of the OpenWebRX server functionality which can be used to put your IC-7300 or IC-9700 'online'. If the beta-installer doesn't exist, there is no 'beta' at the moment, so use the release version above. Details about the new installer (with separate 'Program' and 'Data' folders) are here. If the new installer doesn't work on your system (especially Vista / Windows 7), please report your observations on the Spectrum Lab User's group at groups.io - thanks in advance .As an alternative, check the download section onKo Versteeg's website .Don't trust any other download site - neither "softpedia", nor "freedownloadmanager",nor anyone else because you never know what those sites did to/with the files.Some of those sites claim they performed an extra 'virus check', but noneof those site's owners has ever asked me (the author of Spectrum Lab) for permissionto re-distribute or even re-package the installer, so 'by default' I would not trust any of these sites.The archive includes EXE-file, sample setting files, help system (in HTMLformat) and a few other goodies, but not utilities below.Some additional utilities which may be useful: Winamp output plugin to send audio data directly from Winamp to Spectrum Lab (not via soundcard) FFT filter plugins allow you to insert your own subroutines (compiled into a DLL) into the signal path, where signals are processed in the frequency domain . Soundcard utility sourcecodes contains an example to send an audio stream to Spectrum Lab, using WM_COPYDATA messages. The zipped archive also contains the "C" headers with structure definitions for interaction between SL and other applications (audiomsg.h) . If you want to write your own program to control Spectrum Lab, readthis document which explains howto communicate with it using simple WM_COPYDATA messages (the same datastructures are used to exchange audio via UDP or TCP, too). 2ff7e9595c