I have had 32-bit Largo in use for some time in Sonar X3 64. Waldorf has finally released its 64-bit versions (albeit as RCs). So I have installed the 64-bit VST3 version, and I notice that somewhere between Sonar and Largo, Channel Pressure/Aftertouch is failing to get through, although it is fine in the 32-bit bridged version. To help with the process of elimination, I have loaded 64-bit VST3 Largo in VST Host, where Channel Pressure works exactly as expected. On the face of it, that suggests a problem with X3. Anybody had similar experience and/or know of a fix/tweak/settings change that I need to apply?

Hi - check Preferences>MIDI>Playback and Recording for the check box option settings.
 
Bob Bone
 

Bob - Thanks for the suggestion, but that is not the issue. The Channel Aftertouch is checked and Aftertouch works with other plugs - just not the 64-bit Largo. This would normally cause me to suspect a bug in the specific plug. But in this case, the plug works fine in another host.

Woo-hoo for 64-bit Largo!  One of my go-to, favorite soft-synths! It's also fun to use the Waldorf Q to program Largo! Pretty much 90% of the controls are matched up to the hardware knobs and MIDI CC's. And I can finally put Largo in the Multi-Dock! Suh-weet!
 
Anyway...back on topic...
 
I cannot seem to get aftertouch to work at all for me using my A500pro keyboard. It's aftertouch capable, but I don't fully understand how it works anyway. It can do poly pressure or channel pressure. I assume channel pressure is the correct choice for most cases, basically for simple expressive use?  I want to try to help you. ChristopherM, when you press a key harder, i.e. initiate aftertouch, does this (or should this) cause the meter to light up or pulse on a MIDI track? If so, then wouldn't that be a method to know you're at least receiving MIDI aftertouch data?
 
Slightly off topic... Largo still seems to not load my user patches correctly upon opening a project.  Are you experiencing this?

Hi 2:34am. Remiss of me - I should have posted here that the KVR Waldorf forum, which includes some of the Largo 64-bit beta testers, seems to have agreed that the aftertouch issue is a bug in the VST3 64-bit version (although not in the VST2). As we are at Release Candidate 2, I'm hopeful that Waldorf will fix this before the final production release.
 
I was never in any doubt that Sonar was receiving Channel Pressure, as the top segment of the MIDI track meter flickers to confirm it when I press down on the keys, as you say.
 
To your questions, Channel Pressure can be regarded as just like any MIDI Continuous Controller - the effect it has depends entirely on how the plug-in in question is designed and how the given patch is set-up. In Largo, Channel Pressure is available in the modulation Matrix as a modulation source, so you can use it pretty much to modulate anything - pitch; filter cutoff; volume, etc. Largo also provides a special source, being LFO x Channel Pressure, which typically can be used as an alternative to using the mod wheel to create vibrato.
 
Poly Pressure is slightly different in that the control is particular to the key (note) that is generating it - in other words, every key that is in a Note On state is generating its own controller. As you can imagine, this places even more of a requirement for the plug-in to do something useful with the control signal. It also would imply that the player needs more digital dexterity to get the desired result. In practice, it is rarer than Channel Pressure (and none of my keyboards generates it) but IIRC Largo can use it as a mod source.
 
I haven't noticed any bad behaviour in patch loading, but if you say more about it, I'll take a closer look.