Audio Plugin Testing

Hi, and welcome to something I hope is helpful to you — some simple testing of audio plugins which you can use for comparing, or just to find out more about each one. Each plugin has charts displaying linear and harmonic analysis, and my comments. (Which may or may not be helpful, but it’s my blog and I can do what I want…!) Please visit my Preset Shop as well. I have presets for UAD, SoundToys, Waves, FabFilter Saturn 2 (and more on the way) and a freebie for Airwindows. I will be posting new tests regularly, so please check back! #cool4yourmusic…


All the tests are done at 96/24, not for some nebulous technical reason that we could all start arguments about, but because that is the workflow I have chosen to use. The results allow for observing some very specific behaviors that I find are important to assessing programming integrity and overall sound quality. (This is not a be-all-end-all, simply a good starting point.)

The plugins are at their default setting, except I adjust the input (if necessary) to be as close to -18dBFS RMS input as possible. I also adjust compressors to have a slight gain reduction. This keeps the results consistent, and should be seen as “starting points.” The first chart shows the frequency distribution for the plugin, responding to pulsed white noise. The second chart records total harmonic distortion (THD) and visually shows harmonics and noise. I have added a “gray” area below about -144 dB, because nothing down there is ever going to be audible. (Please note the frequency chart usually has a range of ±6 dB. Occasionally this is extended if the test shows large variations.)

One other check I often do but I did not include is measuring the THD for a sine wave sweeping from 20Hz to 20kHZ. This is similar to doing the Hammerstein test in PluginDoctor (see below) as it can show THD variations based on frequency and can also show aliasing creeping in that might not be apparent with a static signal. I find it more straightforward and actually more informative than the Hammerstein analysis (as fun as it is to track the individual harmonics with it). Because it would involve screen recording and then converting to GIF or some “moving” format, I haven’t included these. If a plugin shows crazy aliasing with this test, or just some obviously-not-in-the-hardware-but-bad-programming behavior I don’t bother using it. Which brings me to my next point—


I am mostly including plugins I think are processing the sound with the highest quality. (I throw in an occasional “outlier” or freebie that interested me.) That doesn’t mean if one isn’t here it is no good. What it does mean is the ones included are (in my opinion) good plugins. Although I throw in a few comments or hints, I am not writing reviews. Please make your own judgements and comparisons. (Using search and categories is helpful for this.)

I add new posts as I catch up or acquire new things. The tests are done using PluginDoctor from DDMF and Voxengo Span with some additional custom sound files. If you like, you can pick these up and start doing your own testing. Or you can save yourself the time and just look here! Click on the pics of the plugins to go their websites. (Disclaimer: some are affiliate links.) Again, please visit my Preset Shop — I hope you can find something helpful there as well!


2 thoughts on “Audio Plugin Testing

Leave a Reply