why the playback template loads multiple instances of the player when applied ??
Firstly, there is no Multi-output VST in the Windows version of ARIA, so you can’t load multiple instruments into one VST and have them on separate channels in Dorico’s mixer.
Secondly, if you save an Endpoint with one Multi-output ARIA VST that has 16 instruments, the VST would always load all 16 instruments, even if you only used one in your project.
Loading 16 instances of ARIA Player with 1 instrument, instead of 16 instruments in 1 VST, uses slightly more CPU – but not 6 times as much! The memory requirements are very similar.
(Reluctantly) I beg to disagree. You can set the outputs of the (Windows) ARIA Player Multi to different channels, and they will come back on separate mixer channels.
Is that VST3 or VST2? It’s been reported quite heavily that there’s no VST3 Multi on Windows; but I’m happy to be proved wrong. (What’s the version number of ARIA – in the Settings tab?)
Something else which I was going to say is that on Mac at least, the multi-output VST(3) seems to ‘leak’ some sound from all the other channels into 1/2. Possibly the Reverb…?
It is the VST2. (As you say, there is no Windows VST3 Multi). But the VST2 Multi works fine (for now)!