All three signals are phase-locked together and available at the same time. There is the Dry or the original audio untouched, Spank is a heavily compressed duplicate, and a well-saturated copy is called Heat.

Parallel processing is nothing new--most stereo plug-ins have wet/dry controls but Parallel Aggressor is designed to give you more control and tonality characters but without elaborate plug-in configuration and 'tweaky' plug-in and bus routing.

I definitely liked the white GUI for a change (from black) but there is also a black GUI too. Spank and Heat styles are represented with two separate level-dependent pulsating semi-circles located on the left and right sides of the GUI. You can solo Spank, Dry and Heat levels using buttons under each mixer fader to hear what each is contributing to the sound.

Spank is a punchy compression algorithm that takes up where Baby Audio's "I Heart NY" plug-in left off but with sonic improvements, better signal detection and flexibility. Spank can be furthered tailored with "injection buttons." They are Extra Punch, Extra Smack, a Sidechain Filter, and Mono where the Spank audio is summed to the center of the mix leaving the Dry and Heat components in full stereo.

Heat is analog-modeled saturation with an aggressive bite. It is based on Baby Audio's tape saturator from Super VHS and also has its set of injection buttons labeled Extra Hot, Tone, HP Filter, and LP Filter. Heat by itself is a useful distortion plug you can get very fuzzy with it.

Lastly, Auto Gain matches output level to the Dry signal and is good for experimenting while still keeping legal levels or when you're in a hurry getting a demo mix done!

Parallel Aggressor from Baby Audio sells for $49 for download and runs in VST, VST3, AU, and in AAX hosts.