VSampler 2 FAQ
The distribution of VSampler 2 has been officially ceased in october 2003 in
favour of VSampler 3.
The FAQ will stay online for VSampler 2 users.
1. Is there a soundcard you could recommend for VSampler? What's better, DirectX/WDM or ASIO?
2. When starting VSampler Standalone it says "The primary DirectSound output device does not support hardware mixing. You may experience performance problems." I have the latest DirectX version installed - what can I do?
3. What does "latency" mean and why is a low latency important?
4. When I press a key there's a delay (latency) till I hear the sound, that's annoying! What can I do to lower the latency?
5. I get stuttering sound and tons of clicks & pops, what to do?
6. I get occasional clicks now and then, what to do?
7. I get doubled notes or hanging notes, what could this be?
8. I get distorted sound sometimes, what to do?
9. When I press the key the sound starts with a click, what to do?
10. When I hold down a key with a looped sample, there is a slight click occuring at regular intervals, what's that?
11. When I release the key the sound ends with a click, what to do?
12. I'm running VSampler as DXi under Cakewalk Sonar, but my soundcard doesn't have WDM drivers, so there's a very high latency, any idea of a workaround?
13. I can't run VSampler Standalone and the MIDI sequencer together, they seem to block each other, why?
| 1. Is there a soundcard you could recommend for VSampler? What's better, DirectX/WDM or ASIO? |
|
VSampler as VSTi or DXi plugin inside a sequencer:
There's one important thing you need to know: the audio
output chain is VSTi/DXi plugin --> host sequencer --> soundcard. That means:
there is no communication between VSampler and your soundcard, that's all done
by the host sequencer. That means: either your soundcard works well with your sequencer
and VSTi/DXi-plugins in general or it doesn't, VSampler won't change that.
For playing back sequencer tracks:
due to the architecture of the VSTi/DXi
plugin interface you get sample-precise timing with every soundcard and every
VSTi/DXi plugin, the sequencer automatically adjusts that, there will be no
latency, zero.
For recording/playing a sequence from a MIDI keyboard:
you need a soundcard
with low latency drivers, either ASIO (e.g. Cubase) or WDM/DirectSound (e.g.
Sonar). Check KvR for a list of soundcards
and their latencies.
|
Standalone version of VSampler:
You need a soundcard
with low latency drivers, either ASIO or DirectSound. ASIO is recommended,
because ASIO drivers usually allow lower latency and more reliable performance
than DirectSound drivers. Either way, DirectX itself is limited to a maximum of
32 voices, so that cuts VSamplers 64x polyphony to the half. Check KvR for a list of soundcards
and their latencies.
We use several RME
cards here, and are very satisfied, the
TerraTec DMX 6fire works
very well with ASIO as well.
|
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| 2. When starting VSampler Standalone it says "The primary DirectSound output device does not support hardware mixing. You may experience performance problems." I have the latest DirectX version installed - what can I do? |
| Nothing. But don't panic, that's just an information, nothing to worry about. Some soundcards are able to mix multiple DirectX voices in hardware (e.g. the SB Live / Audigy) and others do that in software by their soundcard driver. You as user won't feel any difference. The software-mixing takes a bit more CPU, that's all. But it sounds the same :) |
|
| 3. What does "latency" mean and why is a low latency important? |
| The "latency" is the delay between the command (e.g. the NOTE ON) and
the execution of this command (e.g. your soundcard plays the sound). The shorter
this delay the better, the closer to the feeling of playing the keyboard of a
hardware synth. The factor which defines that delay is the buffer size for the
communication between sequencer/instrument and soundcard. The smaller the buffer size, the
smaller the latency, but the higher the risk to get clicks and stuttering sound.
How low you can go depends on the quality of your soundcard's driver. See next
question too. A buffer size of 512 samples played back at 44100 Hz
would take 1s * 512/44100 samples = 12 ms, that's a typical buffer size for a
good driver, most people won't notice this delay. Very good cards have a latency of 3 ms or even
less, e.g. the RME
Hammerfall. Check
KvR for a list of soundcards and their latencies. When playing back tracks
from a VSTi/DXi-capable sequencer there is no latency at all, the sequencer
automatically adjusts that. |
|
| 4. When I press a key there's a delay (latency) till I hear the sound, that's annoying! What can I do to lower the latency? |
|
The factor which defines the latency is the buffer size for the communication
between sequencer/instrument and soundcard. The smaller the buffer size,
the smaller the latency, but the higher the risk to get clicks and stuttering
sound. How low you can go depends on the quality of your soundcard's driver.
|
|
VSampler as VSTi or DXi plugin inside a sequencer:
There's one important thing you need to know: the audio output chain is
VSTi/DXi plugin --> host sequencer --> soundcard. That means: there is no
communication between VSampler and your soundcard, that's all done by the host
sequencer.
Enter the audio preferences of your host sequencer, lower the buffer size to
the smallest setting which produces stable sound output without stuttering or
clicking.
|
Standalone version of VSampler:
You need a soundcard
with low latency drivers, either ASIO or DirectSound, while ASIO is recommended. Check KvR for a list of soundcards
and their latencies.
|
|
|
| 5. I get stuttering sound and tons of clicks & pops, what to do? |
| See previous and next question, please. |
|
| 6. I get occasional clicks now and then, what to do? |
| See previous question(s), maybe you just have to raise the buffer size a little
bit and the clicks disappear. Or it might be slight digital clipping, try to
lower the output level a bit. This can be done at the "Mixer" page, either lower
the master level or the level of the particular MIDI channel. Or it might be a
ressource problem of your hardware, e.g. certain VIA chipsets don't stand high
PCI bus data transfer, or enabled ACPI might cause the problem (check next
question).
But it also might be a generel problem of your PC, this might be true even if
you don't have problems with any other program. Getting a PC to run smoothly as a Digital Audio Workstation can be
a tricky task, here are some great links about Audio PC optimization and
possible hardware problems and how to solve them:
http://www.tweakheadz.com/troubleshooting_audio_cards.htm
http://members.optushome.com.au/skinah/clicknpops.htm
http://www.bluelifeaudio.com/~pcconfig
(dead at the moment)
http://members.optushome.com.au/skinah/AudioTips.htm
http://www.funklogic.com/pcaudio.htm (WIn98 related only)
A great help in combination with those ressources is
SiSoft
Sandra - the System ANalyser, Diagnostic and Reporting
Assistant. |
|
| 7. I get doubled notes or hanging notes, what could this be? |
| Your system has a ressource-problem. This can have many reasons, one of them
might be you are running Win2k or XP in ACPI mode, your soundcard produces lots
of PCI bus traffic (e.g. the SB Live / Audigy) and your motherboard chipset
doesn't like that (the famous VIA chipset bug ...). Quote from the Cakewalk tech
site: "Although ACPI is designed to allow easy integration of power management
and PCI Bus resources, we have seen numerous cases where disabling ACPI improved
performance and eliminated resource conflicts.". For instance the M-Audio
(MIDIMAN) support recommends to disable ACPI for their cards Delta 44/66 and
Delta 1010. Do this if you experience crackles in the audio signal or MIDI
timing problems. Check "A
step for step of how to disable ACPI mode in Windows XP" by Andy
Maddock/Cakewalk. Warning: Disabling ACPI will totally remove the device and
driver configuration of your computer, have all your drivers handy before you do
this. |
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| 8. I get distorted sound sometimes, what to do? |
| Might be digital clipping. Before you blame VSampler you should check the sample itself, load it into an external sample editor and play it back, if the waveform is distorted already VSampler can't do much about that. If the waveform is OK that means you have to lower the output level in VSampler a bit. This can be done at the "Mixer" page, either lower the master level or the level of the particular MIDI channel. |
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| 9. When I press the key the sound starts with a click, what to do? |
| The sample starts at a non-zero value, to be sure that's true load the sample into an external sample editor and play it back. If it starts with a click either do a very short "fade in" in the sample editor itself and save the sample, or raise the attack time of VSamplers volume envelope from 0 ms to 10 ms. The better way is doing it in the sample editor and apply the change to the sample itself. |
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| 10. When I hold down a key with a looped sample, there is a slight click occuring at regular intervals, what's that? |
| The sample isn't looped correctly, the borders of the loop start and end do not match as perfect as they should. Just load this sample into an external sample editor such as Soundforge or Wavelab, do a 1% crossfade of the loop and save the sample, this should fix the problem. |
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| 11. When I release the key the sound ends with a click, what to do? |
| Go to VSampler's "Volume" page and check if the release time of the volume envelope is set to 0 ms (immediate cutoff), if yes, raise it to 10 ms or more. To raise the release time for all Splits at once you have to set the Edit Group to "All Splits of Preset" before you change the volume envelope, otherwise you will just change one of the many Splits your instrument might have. |
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| 12. I'm running VSampler as DXi under Cakewalk Sonar, but my soundcard doesn't have WDM drivers, so there's a very high latency, any idea of a workaround? |
| Maybe, try to use the Standalone version of VSampler when recording, not the DXi. Usually that's a weird idea, because you loose all the advantages of the integration of VSampler into the host sequencer and have to deal with virtual MIDI cables. But it may help lowering the latency, especially if your soundcard got ASIO drivers, which can be used by VSampler, but not by Sonar. Anyway, you might run into another problem, see next question. |
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| 13. I can't run VSampler Standalone and the MIDI sequencer together, they seem to block each other, why? |
| That means your soundcard driver can't be shared between multiple programs, it's not "multi client" capable, only one program
can access the soundcard, all others get a "device busy" message. This applies
to both, audio and MIDI. Some programs will show you this "device busy" message
(or something similiar), some programs just hang. There's no solution for this
problem, except buying another soundcard, as e.g. the SB Live family, or running
VSampler as DXi or VSTi inside of the sequencer. This might happen even
if you got a multi-I/O soundcard and use different outputs for VSampler and the
sequencer (which usually should work!), e.g. the RME cards (which are great in
all other aspects, software and hardware) cards block DirectX against ASIO
generally. |
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