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Synchronization
Using a KVM switchbox
If you want to set up a multi-computer network, or even a
small network in a limited space, it is a good idea to invest
in a KVM (Keyboard, Video, Mouse) switchbox. With one
of these you can use the same keyboard, monitor, and
mouse to control each computer in the system, and switch
between computers very rapidly. KVM switchboxes are
not too expensive, and very easy to set up and operate. If
you decide not to go this route, the network will function
just the same, but you may end up doing a lot of jumping
from one machine to the other while setting up!
Making connections
Below, we assume that you are connecting two comput-
ers. Should you have more than two computers, it is still
best to start with two and add the others one by one once
the system is working – this makes troubleshooting easier
if you run into problems. For two computers, you will need
two digital audio cables, one in each direction:
1. Use the first digital audio cable to connect digital out-
put of computer 1 with the digital input of computer 2.
2. Use the other cable to connect the digital output of
computer 2 with the digital input of computer 1.
• If a card has more than one set of inputs and outputs,
choose whichever one that suits you – for simplicity usu-
ally the first set is best.
Synchronization
Before you proceed, you need to make sure that the clock
signals on your ASIO cards are synchronized correctly.
This is essential when cabling any kind of digital audio
system, not just VST System Link.
The Clock Mode or Sync Mode is set up in the ASIO con-
trol panel of the audio hardware. In Cubase AI, you pro-
ceed as follows:
1. Pull down the Devices menu and open the Device Set-
up dialog.
2. On the VST Audio System page, select your audio in-
terface from the “ASIO Driver” pop-up menu.
The name of the audio interface now appears as a subentry to the VST
Audio System entry in the Devices list.
3. Select your audio interface in the Devices list to the left.
4. Click the Control Panel button.
The ASIO control panel appears.
5. Open the ASIO control panel on the other computer
as well.
If you are using another VST System Link host application on that com-
puter, check its documentation for details on how to open the ASIO con-
trol panel.
6. Now, you need to make sure that one audio card is set
to be the Clock Master, and all the other cards are set to
listen for the clock signal coming from the Clock Master,
i.e. they must be Clock Slaves.
The naming and procedure for this differs depending on the audio hard-
ware – consult its documentation if required. If you are using Steinberg
Nuendo ASIO hardware, all cards default to the “AutoSync” setting – in
this case you must set one of the cards (and only one) to “Master” in the
Clock Mode section of the control panel.
• Typically, the ASIO control panel for an audio card con-
tains some indication of whether the card receives a proper
sync signal or not, and the sample rate of that signal.
This is a good indication that you have connected the cards and set up
clock sync properly. Check your audio hardware’s documentation for de-
tails.
The only exception to this procedure is if you are using an
external clock – which could be from a digital mixing desk
or special Word Clock synchronizer for example. If so, you
must leave all your ASIO cards in Clock Slave or AutoSync
!
All digital audio cables by definition always carry a
clock signal as well as audio signals, so you do not
have to use a special Word Clock input and output
for this (although you may find that you get a slightly
more stable audio system if you do, especially when
using multiple computers).
!
It is very important that one and only one card is the
clock master, otherwise the network cannot function
correctly. Once you have set this up, all the other
cards in the network will take their clock signal from
this card automatically.