1. Spectrum Analyzer Vst Free
2. Spectrum Analyzer Plugin Free
3. Spectrum Analyzer Vst Free Trial
4. Free Visualizer Vst

If you use Wavosaur for mastering / premastering, or signal analysis in a more general way, you need tools for audio analysis : spectrum analyzers, phase analyzers, sonogram.
Wavosaur comes with analyzers, you’ll find them in the ‘tools’ menu, along with oscilloscopes & statistics about the sound file (maximum sample peak, RMS power, average value.).

But you can also use VST plugins (for some people it can be more convenient).
We have searched deep deep inside deep deep down inside into the web, to find the best free VST plugins for audio analysis, here’s the selection:

1) Spectrum Analysis

1.1) Voxengo SPAN

Explore & download the best free Spectrum Analyzer (VST, AU, RTAS, and Stand Alone App). Visit and discover thousands of pro audio and music freewares! Free reverb delay vst effect plugins. Spectrum Analyzer is an Android App that makes it possible to make an analysis of sound waves right from your phone. The app comes in two variations; there is the free app version while there is also a premium version. The free version also comes with some cool features such as tap to pause and does not have Ads.

LVC-Meter Is A FREE Spectrum Analyzer VST/AU Plugin By Tomislav Zlatic on April 10, 2020 News LVC-Audio has released LVC-Meter, a freeware audio metering utility in VST, VST3, AU, and AAX plugin formats for digital audio workstations on Windows and OS X.

This spectrum analyzer uses FFT to display the signal frequency in real time.
You can freeze the display, and use the mouse to shows dB values / Frequency value
Frequency is displayed in Hz and in musical note.
The Voxengo SPAN analyzer also displays statistics : RMS power, and it features a clipping detection.

More info and download @ http://www.voxengo.com/product/span/
It is worth mentioning these plugins too, freeware!

Seven Phases Spectrum Analyzer is a real-time spectrum analysis VST plugin. The idea was to create an old-fashioned tool reminiscent of classic hardware analyzers of the earlier centuries. Unlike most of other analyzers available these days, this plugin is not FFT-based but utilizes a filter-bank algorithms that mould its unique pros and cons. Explore & download the best free Spectrum Analyzer (VST, AU, RTAS, and Stand Alone App). Visit and discover thousands of pro audio and music freewares! SPAN is a free real-time “fast Fourier transform” audio spectrum analyzer AAX, AudioUnit and VST plugin for professional sound and music production applications. SPAN provides you with a very flexible “mode” system which you can use to setup your spectrum analyzer preferences. This spectrum analyzer uses FFT to display the signal frequency in real time. You can freeze the display, and use the mouse to shows dB values / Frequency value Frequency is displayed in Hz and in musical note. The Voxengo SPAN analyzer also displays statistics: RMS power, and it features a clipping detection.

1.2) Mdsp SmartElectronix Fre(a)koscope

Very nice, with interesting options for the spectrum display : linear/logarithmic/semitones .
Adjustable size for the FFT buffer. Had sometimes display problem with Wavosaur.
More info and download @ http://mdsp.smartelectronix.com/freakoscope/

1.3) BlueCat FreqAnalyst

Like the previous VST effect, this one can show spectrum of left / right channel or both, has a “hold peak” feature that is interesting, when dealing with EQ level in your mix.
More info & download @ http://www.bluecataudio.com/Products/Product_FreqAnalyst/

1.4) Seven phase Spectrum Analyzer

This one is freely resizable inside the host application (works in Wavosaur)
More info and download @ http://sevenphases.wordpress.com/spectrum-analyzer/

1.5) MultiInspector free

Download @ http://www.vertexdsp.com/downloads.html#MultiInspectorFree

Spectrum Analyzer Vst Free

2) Sonogram

Spectrum Analyzer Plugin Free

2.1) ag-works sonogram sg-1

This free plugin displays a scrolling sonogram for frequency analysis.
You have the choice for the sonogram colors, and many options to tweak the sonogram displays
This is the only sonogram VST we have found for free ! Fortunaly it’s very good.
More info & download @ http://ag-works.net/plugins.sg1.htm

3) Goniometer

3.1) Flux Stereo Tool

When you need to visualize your stereo position, and the repartition in the field, this plugin is very useful. You can check for phase errors in your mixes.
download @ https://www.fluxhome.com/download

3.2) Gonio3

download @ http://www.uk-music.de/index.php?page=downloads

3.3) HOFA 4U Goniometer & Korrelator

download @ http://hofa-plugins.de/pages/start_en/4u_en.php

If you think that we have forget some free VST analyzer plugin in this list, do not hesitate to comment !

Edit:

Spectrum Analyzer Vst Free Trial

We just have found this pretty nice analyzer somewhere on our harddisk :

Dust Analyzer:

It provides three modes : spectrum / scope / phase , with “hold peak” option, freeze option, dB/Freq display with mouse, linear / logarithmic scale

Free Visualizer Vst

more info & download @ KvR audio forum & http://www.signaldust.com/ Muffin rider vst free.