I was trying to use a USB audio interface, and it was crackling and skipping like crazy.  Built-in audio is performing much better, which is fine because the latency with basic ALSA settings is sufficient.

I'm trying to work on a suspend/resume script that restarts Pianoteq, since it doesn't always pick up the USB MIDI connection when it resumes.  The downside is that PT still doesn't remember the CPU overload protection (and multi-core rendering?) settings in Linux. (EDIT: I may be mistaken about this - it's been doing well being restarted the past few days.)

I wish that a MIDI device can be somehow connected to the X idle time, then I could have it auto-suspend (and resume?).

I might try an LMMS+VSTi interface (I've read it's possible - google "lmms vsti") when I get my small touchscreen monitor, unless PT makes a basic small-screen/full-screen option. (which would be perfect!)

I would search and see if your card supports Linux -- if so, you will get outstanding performance.  My performance index on the same hardware went up to 18-19 and that is still with other programs running!  There is plenty of headroom even on my 1.5ghz C2D, 48khz and 128 note polyphony.

ALSA provides great low-latency performance with Pianoteq out of the box (without real-time kernel).  If you are using JACK you *might* need the real-time kernel to ensure super-low latency with no xruns.

ethan

Thank you for you extensive explanation. ;-)
Because I'm going to use it during live gigs, I'm still a bit withholding because I'm not quite sure when to get the best performance with my RME card: Windows or Linux. I would personally prefer Linux if there's no performance penalty.

And second: the Linux version of Pianoteq is also VST capable? This is really important because I want to run multiple instances controlled from one program.

Cheers,
Herman

standard Ubuntu 9.10 installation on Dell XPS m1330 2gb T5250
w/separate partition for /home

setup the desktop however you want -- i disable unnecessary services (e.g., i don't use bluetooth or evolution, including the clock/calendar applet).  i have installed gnome-do and configured it to be like the MacOSX dock -- very cool and functional.

system > administration > users and groups > add your user to "audio" and "video" groups

https://help.ubuntu.com/community/UbuntuStudioControls
https://help.ubuntu.com/community/FireWire  -- ignore rtirq for now (see below)

edit /etc/security/limits.conf to add the following line if it doesn't exist -- the other two parameters (memlock and nice) should be there from UbuntuStudio Control

"@audio - rtprio 95" or similar priority

my rtprio is 85 and nice is -15.  with rtprio and nice i worry about audio competing with essential system processes if i set them too high, so this is good middle ground for me

gnome panel:  right click, add cpufreq scaling monitor applets x 2
use these to enable "performance mode" on both cores.  In Pianoteq this gives me 15-20% more CPU headroom.  when i am finished with audio work, i just change it back to "ondemand" to save power/heat/battery life.  also helpful to close firefox and disable networking (software AND hardware kill switch) during audio work.

the last step would be to add the linux-rt kernel and install and setup rtirq:
http://ubuntuforums.org/showthread.php?t=1328175

i haven't installed a the linux-rt kernel yet.  two questions i have about the linux-rt kernel:  1. does it allow cpu freq scaling?  2. can i suspend/hibernate my computer with it?  even if it doesn't, i may still install it and install/configure rtirq in case i need better performance, so i can reboot with the linux-rt kernel as necessary, e.g., when i do more recording work/longer sessions.

after setup is done, install whatever programs you need (jackd, qjackctl, ffado, etc) and configure them appropriately.  i can run Pianoteq with either ALSA backend (Intel HDA 2.0 integrated soundcard -- sounds great!) or JACK backend.  With jack, i can use either ALSA or FFADO (firewire) for my AudioFire2 sound card.  Full access to soundcard settings via ffado-mixer. 

qjackctl automatically suspends PulseAudio, so there is no hardware conflict.  Normal audio resumes when exiting qjackctl.  the bonus is higher JACK performance.  on the other hand, if there is ever an option to allow JACK to exist on top of PulseAudio, then you can play/record from ANY sound-generating application (think: mplayer, firefox/youtube, rhythmbox) with JACK.  i haven't gotten this to work, but am not sure i want/need it.

at any rate, this beats a dual-boot setup by far!  all my files and programs are in one convenient location with minimal interruption in work flow

There is no installation step on linux, so you can put the executable anywhere, that should not make a difference.

1. Can Modartt please provide a launcher icon for the linux version of Pianoteq?  I would like to create launchers for it with a suitable icon.

2. also to confirm:  I am unused to a universal binary -- how do I install it?  Do I just leave the folder in my /home directory, or do I move it to something like /usr/local/bin/?

Also, I would like to gush:

after a bit of tweaking, i have Pianoteq running in real-time very nicely with ALSA or JACK on my Ubuntu 9.10 laptop with the standard (non-RT) kernel.  This includes access to my external firewire audio device(!), with low latencies.   It was astonishingly simple to set up.

Pianoteq is performing better than ever (performance index jumped from 14 previously to 18-19 now), and that is with a network connection, bittorrent client, and firefox (several windows) running!

...if i truly need real-time stability (e.g., for pop-free recording), i may just be able to complete the tweaking by installing rtirq and booting with the linux-rt kernel as necessary...

this is closer to my dream of a simple setup (no dual boot!) that does everything i need it to without having any major interruptions in work flow.