Airwindows has released ToneSlant, a free plug-in for Mac OS X and Windows in AU and VST formats and described as a mastering grade very low Q tilt EQ. Here's the story in their own words...
ToneSlant is based on a variation on the Average concept. Turns out, it's the tail end of the 'averaged samples block' that causes the cancellation node. ToneSlant implements a much bigger sample block (100 taps) but linearly fades the samples off between the first and last sample in the block.
What that does, is produce an extremely transparent 'tilt EQ' with a controllable corner point. And, it's implemented in such a way that you can set it to null out (at extreme high boosts) and then bring in only the brightest highs (shown in the video). Quirky, maybe, but it broadens the ToneSlant toolkit. So, the main uses are:
These come out of the algorithm: the reason it performs so well sonically is both the extremely low Q and the simplicity of the algorithm. Not everything I make belongs in a mastering studio, but ToneSlant is peculiarly suited to that use: it's like those specialty EQs that have very few parts and impart no color to the sound. You should be careful applying ToneSlant, because it 'hides' and tries not to be apparent as EQ. Use it as such, when you need perhaps a strong 'tilt' but don't want the result to sound equalized.
Pricing and Availability:
Free
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