Quality settings in offline rendering (DAW)

Not sure exactly what you mean or are referring to by "high quality." There are many factors that contribute to various types of quality regarding audio and the performance of audio-producing software like Pianoteq or the various DAWs.

I currently use Linux (rather than Windows or MacOS), and use Pianoteq running as a plugin inside a DAW (Ardour), with a sample rate of 96 kHz per second for both the DAW and for Pianoteq's internal sample rate (I typically use 48 kHz, but used 96 kHz for this stress test), 256 samples per buffer/period (which at that high sample rate results in just 2.7 milliseconds of latency), Pianoteq's polyphony set at its maximum of 256 simultaneously-sounding notes, with the computer CPUs set to their highest rate and using the "Performance" governor to maintain rapid response and rapid speed (disabling frequency-scaling).

There are no cracks, pops or glitches in the audio produced by Pianoteq or the DAW, and the CPU load (percent used of the total CPU resources) rarely exceeds 50% despite all of the following occurring at the same time within the DAW--

• Pianoteq (live MIDI input and audio output)

• U-He Diva synth (responding to the same MIDI input as Pianoteq and producing audio)

• Seven previously recorded audio tracks, all played back simultaneously while sending MIDI live to both Pianoteq and Diva.

• Recording the Pianoteq plugin's real-time audio output onto another track.

This seems to me to be both high-quality and fairly-high performance, for both the DAW and for the Pianoteq plugin and its audio output.

While using Pianoteq as a plugin in a DAW, you could try to reduce Pianoteq's internal sample rate when you need to reduce CPU-usage, and raise it when you want to record Pianoteq's audio output. You could record the MIDI being sent to Pianoteq as you accompany the other audio tracks, then mute the other audio tracks, raise the sample rate of Pianoteq, and record the audio output of Pianoteq as it plays back the previously-recorded MIDI.

https://i.imgur.com/LgBi4UR.jpg

I'll chime in-- and hopefully not pile on-- as someone who uses multiple DAWs, sometimes at the same time, but also uses just Pianoteq standalone by itself, I will say that how you configure a DAW and track(s) within it can affect performance in many ways. So look to that. Also I noticed Pianoteq Options may reset themselves when used in plugin form vs the stand alone-- which makes sense-- but you can also check there. Best of luck!