Sound Quality Problems with JSyn
For programming issues, crashes, error messages, etc. click
here.
Troubleshooting
If you hear no sound from the example programs...
If your own program makes no sound...
If the sound glitches regularly, or when you move
windows...
If you hear seemingly random clicks and pops...
If your sound is occasionally distorted and buzzy...
If the sound stops when using a popup menu on Macintosh
OS 7,8,9...
If you hear no sound from the example programs,
it might be because:
-
your stereo is turned off, or way down, or is not connected (try headphones),
If your own program makes no sound, it might
be because:
-
you forgot to start all the units,
-
or you set frequency or amplitude to a very low level,
-
or you didn't connect to a Line_Out unit so no sound is getting out,
-
or you are missing a connection between units,
-
or DC offset from stopped units is pushing your output completely outside
the range of -1 to +1 so it is getting clipped to a steady/silent value,
-
or a recursive filter has overflowed and become stuck at one value,
-
your stereo is turned off, or way down, or is not connected (try headphones),
-
or DirectSound is hung (more common under NT). Try running one of the published
examples or the DirectX Diagnostic Tool. If it
fails to make sound, you will probably have to reboot.
If the sound glitches regularly, or when you
move windows, it might be because:
-
The latency is set too low for your computer (see the section on latency
in your installation guide).
-
Certain high performance video cards on the PC such as the Matrox Mystique
can hog the bus when rendering. This can cause unavoidable glitches
in audio output when clicking buttons, resizing windows, scrolling, etc.
You should upgrade to the latest video card driver from your vendor which
will probably correct this problem. You can find out more information at
this site: http://www.zefiro.com/vgakills.txt
-
Or you are trying to run too many units at once. Add a UsageDisplay to
your program. If the usage is above 75% then you're pushing it. Try using
fewer units, or running at a lower sampleRate by calling:
Synth.startEngine( 0, Synth.DEFAULT_FRAME_RATE/2.0
);
or buy a faster computer. ;-)
If you hear seemingly random clicks and pops
it might be because:
-
Network traffic on your ethernet LAN may be interfering with your audio.
Try disconnecting from your local area network by unplugging your ethernet
connection, or disabling your network interface.
-
The latency is set too low for your computer (see the section on latency
in your installation guide).
-
Apple PowerBook G3s sometimes have random crackle when playing full
amplitude sine waves. Try lowering the amplitude of your sound.
If your sound is occasionally distorted and
buzzy, it might be because:
-
you are exceeding the limit for the amplitude of all combined sounds. Sound
cards can only produce sound within a limited range of amplitudes. If the
mixed result of all your sounds exceeds the the range of -1.0 to 1.0, then
the sound will clip and sound distorted, particularly during loud passages.
For example, if you add two sine waves together with amplitudes of 0.6
and 0.7, then the combined output can reach 1.3 which is out of range and
will clip. To fix this, set the amplitude ports of your units to a lower
value, like 0.4 and 0.5.
If the sound stops when using a popup menu on
Macintosh OS 7,8,9, it is because:
-
the Apple code that tracks the popup menu takes over the computer and blocks
all low level tasks including audio. Avoid using the AWT Choice component
on Macintosh.
If you cannot find an answer to your question on this website, then please
contact
us directly. Be prepared to describe the sound quality problem. How
frequent are the pops? Are they periodic, or random, or associated with
activity in other programs? When does the distortion occur? Is is steady
or just at certain times?
© 2001 SoftSynth.com
