Ina-GRM GRM Tools ST

Oct 1, 2003 12:00 PM, By Laura Pallanck


Education Guide

Mix is gearing up to present its longstanding annual Audio Education Guide in its November 2014 issue. Want to have your school listed in the directory, or do you need to update your current directory listing? Add an image, program description, or a logo to your listing! Get your school in the Mix Education Guide 2014.

GRM Tools ST (Spectral Transform) adds four exceptional processors — Contrast, Equalize, Freq Warp and Shift — to a plug-in family already packed with winners. Although these FFT-based plug-ins are at their most powerful when used subtly, they practically dare you to attempt the outrageous.


One of my favorite features of the GRM Tools plug-ins is the ability to interpolate between presets. You can do this manually with the SuperSlider or automatically by clicking a Preset tile. Once you have a few choice presets, you can set the rate of change between them from instantaneous to 30 seconds. But you can also exercise real-time control over the changes for improvisatory adventures in processing. For this kind of work, I often use Shift, an exceptionally powerful frequency-shifter plug-in, which features a controller called the Elastic String.

When you hold down the Command key while moving the mouse away from Shift's Scale/Shift icon, the Elastic String appears between the cursor and the icon. Immediately, the icon will begin traveling toward the cursor's position. The longer the Elastic String, the slower the icon will move. This effect allows you to try out different processing trajectories through space in real time. If you like what you find and want to automate it, then you can save each point as a preset and morph between them.

You can also keep the Elastic String to a minimum and quickly tow the icon around the frequency field on a short leash. When you find a resonant place or sweet spot, the short leash allows you to easily circle around it. Remember to keep your CD recorder going when you work this way, just in case you find something special.

If gradual changes aren't working for you, then you can make the Scale/Shift icon jump immediately to any position in the frequency field by clicking anywhere in the field and moving the cursor slightly. This is a great trick when you have a loop going and you want to radically change its sound to the beat.


The Contrast plug-in is a compressor/expander that analyzes your audio input's frequency spectrum. The plug-in's GUI lets you manually determine the comparative amplitude levels of the strong-est (the slider marked S), average (the slider mark-ed M for medium), and weakest (the W slider) parts of the spectrum. You can hone in on the frequency area that you want to modify by moving the vertical delimiters around the target spot: Low frequencies are to the left, and high frequencies are to the right (see above). The position of and distance between the horizontal delimiters determine the relative strength of each part of the frequency spectrum.

Contrast is a great plug-in for mastering-type jobs because you can use it to locate and enhance the weaker parts of the spectrum and bring out lost detail. You can also use it to soften and smooth out edgy and over-the-top aspects of an audio file.


Contrast is also a wonderful tool for finding and exploiting resonant elements in a rhythm track or loop. Begin by narrowing the vertical and horizontal delimiters to their extreme positions, as well as maxing out the level of either the weak- or medium-amplitude controls. Next, hold down Shift, click within the vertical band and slowly move your mouse while listening for resonant peaks or interesting rhythmic artifacts. If you find something you like, then save the position of the delimiter bands as a preset by holding down the Command key and clicking on one of the numbered Preset tiles. Repeat this several times until you've built up a bank of presets. Don't forget to move the position and width of the horizontal bands as you work, because their placement is just as important while you are looking for interesting sounds.

Once you have a handful of presets to work with, set the timing slider to a low value so that your presets change quickly, but not quite instantaneously. Now, toggle through your presets in time to the loop so that different aspects of it pop out to the beat. Gradually increase the interpolation time to greater values until the rate of change locks in with the music over large phrase lengths.


A couple of interesting features added to the native Mac OS X version of GRM Tools ST are the randomizing presets. Preset 15, for example, changes your current settings by 10% in a randomized fashion. This is useful if you're looking for inspiration, but only in small doses. On the other hand, if you're looking for a radical change, preset 16 will randomize your settings completely.

Laura Pallanck wishes to thank Ben Chadabe for assistance with this article.

Acceptable Use Policy
blog comments powered by Disqus

Mix Books

Modern Recording and Mixing

This 2-DVD set will show you how the best in the music industry set up a studio to make world-class records. Regardless of what gear you are using, the information you'll find here will allow you to take advantage of decades of expert knowledge. Order now $39.95

Mastering Cubase 4

Electronic Musician magazine and Thomson Course Technology PTR have joined forces again to create the second volume in their Personal Studio Series, Mastering Steinberg's Cubase(tm). Edited and produced by the staff of Electronic Musician, this special issue is not only a must-read for users of Cubase(tm) software, but it also delivers essential information for anyone recording/producing music in a personal-studio. Order now $12.95



Delivered straight to your inbox every other week, MixLine takes you straight into the studio, with new product announcements, industry news, upcoming events, recent recording/post projects and much more. Click here to read the latest edition; sign up here.

MixLine Live

Delivered straight to your inbox every other week, MixLine Live takes you on the road with today's hottest tours, new sound reinforcement professional products, recent installs, industry news and much more. Click here to read the latest edition; sign up here.

[an error occurred while processing this directive]

The Wire, a virtual press conference offering postings of the latest gear and music news, direct from the source. Visit the The Wire for the latest press postings.