How is the performance, when using more than two output channels?
Thanks for providing this and previous versions of GrandOrgue v 3.
A first report on using the multichannel version briefly.
Test platform: W 7 64 bit Q6600 8GB Ram (already becoming obsolescent)
Focusrite Saffire with latest W 7 drivers
Organ used: PiteaMHS 3 manual + Pedal loaded with all loops, all attacks, all releases, no lossless compression.
1) Using a single stereo channel.
No sound breakdown with any of the different sound drivers.
Lowest latency with WDMKS (PortAudio used) : latency 10 ms with buffers at 64
WASAPI (PortAudio used) : with buffers at 64: still 30 ms, uses Focusrite Saffire WDM driver
with buffers at 1024: 46 ms
Windows Direct Sound (PortAudio used) : 14 ms, uses Focusrite Saffire WDM driver
with buffers at 256; lower buffers gives sound breakdown.
Directsound : 20 ms, uses Focusrite Saffire WDM driver
with buffers at 448; lower buffers gives sound breakdown.
MME (PortAudio used) : 29 ms
with buffers at 640; lower buffers gives sound breakdown.
2) Using 3 stereo channels (Front, Surround, Bass)
With 3 stops drawn in each of the 4 divisions.
WDMKS (PortAudio used) :
with buffers at 384 latency for each stereo channel is 10 ms
lower buffers gives distorded sound
but only manual 1 and 3 play without sound breakup
manual 2 and pedal give stuttering sound
increasing buffers up step by step up to 1024 gives no improvement
WASAPI (PortAudio used) :
with buffers at 512 latency for each stereo channel is 30 ms
lower buffers gives distorded sound
but only manual 1 and 3 play without sound breakup
manual 2 and pedal give stuttering sound
increasing buffers above 512 makes manual 1 and 3 to give stuttering sound
increasing buffers up step by step up to 1024 gives no improvement
Windows Direct Sound (PortAudio used) :
with buffers at 896 latency for each stereo channel is 21 ms
no sound breakup or stuttering sound playing manuals 1 and/or 3
stuttering sound playing manual 2 and/or pedal
with buffers at 960 latency for each stereo channel is 22 ms
no sound breakup playing manual 2
stuttering sound playing manual 1 and/or 3 and/or pedal
Some questions:
- Is there any logical explanation why playing manual 1 and 3 works and manual 2 and pedal not?
The midi channels used are: manual 1 = 1, manual 2 = 2, pedal = 3, manual 3 = 4.
Channels 1 to 3 come from the midi output of the Focusrite Saffire, channel 4 comes from M-Audio 61 usb keyboard.
- Is it logical that Windows Direct Sound using PortAudio gives better latency than WASAPI?
- Any specific tests that could help?
All the best.
Erik.