Physical modelling and MPE belong together. A modelled string, reed or membrane already behaves like a physical object that responds continuously to how you excite it — feeding it per-note pressure and slide is the closest a plugin gets to playing an actual instrument. So the gap between "physical modelling synth" and "physical modelling synth with MPE" has always been the frustrating part.

Tracktion has now closed that gap for Outersect Modeler, whose recent updates bring full MPE support to the instrument. The implementation is worth looking at closely, because it handles a problem most "now with MPE" updates quietly ignore.

What Changed

In MPE mode, Outersect Modeler exposes a per-note bend range on its setup page, set independently of the global pitch bend range on the main page. For controllers that offer a master bender alongside per-note bend — the LinnStrument, Osmose and most Continuum-family instruments do — the master bend continues to follow the main page setting.

That separation is the single most reliable indicator that a developer implemented MPE properly rather than routing channels and calling it done. The MPE specification uses ±48 semitones as the default member-channel range, and controllers ship configured that way. A plugin that applies your global ±2 to member channels will turn a small finger slide into either a comical leap or nothing at all.

In MPE mode, Timbre/Y replaces Classic Modulation and inherits all the same routings across every patch. Which brings us to the part that actually deserves attention.

The Patch Migration Problem

Here is what usually happens when a synth adds MPE. The developer wires up per-note pitch, pressure and slide, ships the update, and every patch in the factory library — all of them built around a mod wheel and channel aftertouch — sits there ignoring your controller entirely. You get MPE support and an empty preset browser at the same time. Building expressive patches from scratch is the price of admission, and for a lot of players that price is too high.

Outersect Modeler's update maps existing standard-MIDI modulations onto their MPE equivalents, so that most patches work in both modes. Load a preset that responded to the mod wheel, switch to MPE, and the Y axis of your controller now drives the same destination.

This is not glamorous engineering. It is also the difference between an update you can use on the day it lands and one that requires a weekend of patch programming first. A large preset library that already responds to your controller is worth more than a long list of routable destinations you have to wire up yourself.

Why It Suits This Instrument in Particular

Outersect Modeler is not a subtractive synth with a modelling badge — it builds sounds from modelled resonators and exciters, which means the parameters exposed to modulation are physically meaningful. Pressure mapped to bow force, slide mapped to strike position or damping, per-note bend mapped to actual string pitch: these are not arbitrary assignments. They correspond to how the instrument being modelled would respond to a player.

That is the argument for MPE at its strongest. On a subtractive patch, pressure-to-cutoff is a convention — pleasant, but conventional. On a modelled body, the same gesture produces the timbral shift the physics would produce anyway. The controller and the engine agree about what a gesture means.

It also puts Outersect in a small but growing group. Physical modelling with genuine per-note support remains relatively rare — Osmose's EaganMatrix engine, a handful of Continuum-oriented tools and now Outersect. Each addition to that list is a meaningful expansion of what MPE players can actually reach for.

Getting It

Existing Outersect Modeler owners can download the current version from the Tracktion website; the update is free. The user guide documents the MPE mode, including the setup-page bend range and the Timbre/Y routing.

If you are trying it for the first time, start by matching the per-note bend range to your controller before judging any preset. Nearly every complaint about a newly MPE-enabled plugin traces back to a mismatched bend range, and the fix takes about four seconds once you know where the setting lives.

Sources: Tracktion · rekkerd.org