Acustica's ACQUA range is a well-regarded series of analogue modelling plug-ins that make use of their dynamic convolution technology. One of these plug-ins, the TAN compressor is available for free. It's a great introduction to their world, and for a free compressor it both sounds excellent, and comes with a nice range of features.
As you would expect for an analogue modelling plug-in, the controls for Threshold, Ratio, Attack and Release are not endlessly tweakable, but there are enough options available through the rotary controls to get the job done. In addition there is a Dry/Wet control, which is always welcome as it makes parallel compression that bit easier to achieve. Finally there is a 'ShMod', or Shape Modulation control, which controls the 'the attack curve of the compressor: it allows you to fine-tune the attack shape so that you can really optimize the attack behaviour for any kind of audio source'.
This final control actually works very nicely indeed, and along with the Dry/Wet control means that this compressor is very well suited to working with drums. The 'ShMod' control makes it very easy to let through just as much of the drum transients as you need; a nicely intuitive way of quickly getting to the sound you are looking for.
TAN is available in AAX, VST and AU formats. Both Mac and PC are supported and both 32 and 64 bit versions are available. You can download TAN for free from the Acustica website.
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