Latency with virtual instruments and MIDI interface / keyboard
When you use one of our MIDI interfaces together with a keyboard or one of
our keyboard controllers to play a virtual instrument, the delay or latency
you might experience depends on the audio interface or soundcard you use for
playback. Latency is the time between hitting a key on your keyboard and the
actual playback of the sound.
To use virtual software instruments (either standalone or as plugin inside
a DAW software such as Cubase, Logic, GarageBand, Sonar, etc.) and play them
in real time, you need a MIDI keyboard connected via a MIDI interface or directly
via USB to your computer and a soundcard or audio interface to playback the
sound that is generated by the virtual software instrument.
The audible latency is caused by the playback, not by the MIDI interface. Because
of that it is a requirement that your soundcard or audio interface has a low-latency
driver. This is often provided via an ASIO driver (for which your software needs
to be ASIO compatible) under Windows or Core Audio support on the Mac. Windows
also uses WDM or MME playback methods, however if the latency can be low in
that case, depends on the used audio interface and driver being used.
The best solution to achieve low latency is to use a professional quality audio
interface with low-latency drivers and to make sure the virtual instrument and
DAW is correctly setup. All ESI audio interfaces provide such drivers. If you
use the onboard soundcard of a desktop PC or PC notebook, you will usually not
find such drivers. In many cases however, using an utility such as ASIO4ALL
can solve the issue if your virtual instrument / DAW supports ASIO. This normally
does not lower the latency to the same level a professional interface provides,
but in many cases it is enough.
Also note: if you use the so-called Microsoft GS Wavetable synthesizer (which
is integrated into Windows and not a virtual instrument or plugin provided as
separate software) as MIDI output inside your DAW software, the latency usually
cannot be reduced. This means that the Microsoft GS Wavetable synthesizer is
acceptable to playback of MIDI data (as you won't really notice the delay then),
but it cannot be used for realtime playback or recording of MIDI data from your
keyboard or via your MIDI interface.