Steinberg Cubase 7 User Manual

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SynchronizationWorking with VST System Link
Making connections
Below, we assume that you are connecting two computers. 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 the digital output of computer 1 to the 
digital input of computer 2.
2.Use the other cable to connect the digital output of computer 2 to 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 usually 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 control panel of the audio 
hardware. Proceed as follows:
1.From the Devices menu, open the Device Setup dialog.
2.On the VST Audio System page, select your audio interface from the ASIO Driver 
pop-up menu.
In the Devices list, the name of the audio interface now appears as a subentry to 
the “VST Audio System” entry.
3.In the Devices list, select your audio interface.
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 computer, check 
its documentation for details on how to open the ASIO control panel.
6.Now you need to make sure that one audio card is set to be the clock master and 
all other cards are set to be clock slaves (i.
 e. they listen for the clock signal coming 
from the clock master).
The naming and procedure for this differs depending on the audio hardware – 
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 contains some indication of 
whether or not the card receives a proper sync signal, including 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 details.
!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 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. 
						

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SynchronizationWorking with VST System Link
The only exception to this procedure is if you are using an external clock – from a 
digital mixing desk or a special word clock synchronizer, for example. In that case you 
must leave all your ASIO cards in clock slave or AutoSync mode and make sure that 
each of them is listening for the signal coming from the synchronizer. This signal is 
usually passed through your ADAT cables or word clock connectors in a daisy chain 
fashion.
VST System Link and latency
The general definition of latency is the amount of time it takes any system to respond 
to whatever messages are sent to it. For example, if your system’s latency is high and 
you play VST instruments in realtime, you will get a noticeable delay between when 
you press a key and when you hear the sound of the VST instrument. Nowadays, most 
ASIO-compatible audio cards are capable of operating with very low latencies. Also, 
all VST applications are designed to compensate for latency during playback, making 
the playback timing tight.
However, the latency time of a VST System Link network is the total latency of all the 
ASIO cards in the system added together. Therefore it is extra important to minimize 
the latency times for each computer in the network.
ÖThe latency does not affect the synchronization – it is always perfectly in time. But it 
can affect the time it takes to send and receive MIDI and audio signals, or make the 
system seem sluggish.
To adjust the latency of a system, you adjust the size of the buffers in the ASIO control 
panel – the lower the buffer size, the lower the latency. It is best to keep to fairly low 
latencies (buffer sizes) if your system can handle it – about 12
 ms or less is usually a 
good idea.
Setting up your software
Now it is time to set up your programs. The procedures below describe how to set 
things up in Cubase. If you are using another program on the other computer, please 
refer to its documentation.
Setting the sample rate
The projects in both programs must be set to use the same sample rate. Select 
“Project Setup…” from the Project menu and make sure that the sample rate is the 
same in both systems.
Streaming digital audio between applications
1.Create input and output busses in both applications and route these to the digital 
inputs and outputs.
The number and configuration of the busses depend on your audio hardware and 
on your needs. If you have a system with eight digital i/o channels (such as an 
ADAT connection), you could create several stereo or mono busses, a surround 
bus together with a stereo bus, or any combination you need. The important thing 
is that you should have the same configuration in both applications – if you have 
four stereo output busses on computer 1, you want four stereo input busses on 
computer 2, etc.
2.Set things up so that computer 1 plays back some audio.
For example, you could import an audio file and play it back in Cycle mode.
3.In the Inspector or MixConsole, make sure that the channel containing the audio 
material is routed to one of the digital output busses. 
						

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SynchronizationActivating VST System Link
4.On computer 2, open the MixConsole and locate the corresponding digital input 
bus.
The audio being played back should now “appear” in the program running on 
computer 2. You should see the input bus level meters moving.
5.Reverse this procedure so that computer 2 plays back and computer 1 “listens”.
Now you have verified that the digital connection works as it should.
ÖFrom this point on in this chapter, we refer to the busses connected to the digital 
inputs and outputs as “VST System Link busses”.
Settings for the audio hardware
When you exchange VST System Link data between computers, it is important that 
the digital information is not changed in any way between the programs. Therefore, 
you should open the control panel (or additional application) for your audio hardware 
and make sure that the following conditions are met:
•If there are additional “format settings” for the digital ports that you use for VST 
System Link data, make sure that these are turned off.
For example, if you are using an S/PDIF connection for VST System Link, make 
sure that “Professional format”, Emphasis, and Dithering are turned off.
•If your audio hardware has a mixer application allowing you to adjust the levels of 
digital inputs and outputs, make sure that this mixer is disabled or that the levels for 
the VST System Link channels are set to ±0
 dB.
•Similarly, make sure no other forms of DSP (pan, effects, etc.) are applied to the 
VST System Link signal.
Notes for Hammerfall DSP users
If you are using RME Audio Hammerfall DSP audio hardware, the Totalmix function 
allows for extremely complex signal routing and mixing in the audio hardware. This can 
in some situations lead to “signal loops” in which case the VST System Link will not 
work. If you want to make absolutely sure this will not cause any problems, select the 
default or “plain” preset for the Totalmix function.
Activating VST System Link
Before you proceed, you need to make sure that VST System Link is set as the 
timecode source in the Project Synchronization Setup dialog and that the desired 
Sync options are activated, see 
“Timecode Preferences” on page 655.
After setting up the inputs and outputs, you now need to define which input/output 
will carry the actual VST System Link information.
The VST System Link networking signal is carried on only one bit of one channel. This 
means that if you have an ADAT-based system which normally carries eight channels 
of 24-bit audio, once you activate VST System Link you will have seven channels of 
24-bit audio and one channel of 23-bit audio (the least significant bit of this last 
channel will be used for networking). In practice this makes no discernible difference 
to the audio quality, since you will still have around 138
 dB headroom on this channel. 
						

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SynchronizationActivating VST System Link
To set things up, open the VST System Link panel:
1.From the Devices menu, open the Device Setup dialog.
2.In the Devices list to the left, select the “VST System Link” entry.
The VST System Link settings are shown to the right of the Devices list.
3.Use the ASIO Input and ASIO Output pop-up menus to define which channel is 
the networking channel.
4.Activate the Active checkbox at the top left of the panel.
5.Repeat the steps above for every computer in the network.
As the computers are made active, you should see the Sending and Receiving 
indicators flashing on each active computer, and the name of each computer should 
appear in the list at the bottom of the pane. Each computer is assigned a random 
number – do not worry about this, it is just so the network knows internally which one 
is which.
•You can double-click on the name in bold (which is the name of the computer you 
are currently working on) and set it to whatever other name you wish.
This name will appear in the VST System Link window of every computer on the 
network.
ÖIf you do not see the name of each computer appearing once you have made it active, 
you need to check your settings. Go through the procedure above again and make 
sure that all ASIO cards are listening to the digital clock signals correctly, and that 
each computer has the correct inputs and outputs assigned to the VST System Link 
network.
Putting the network online
After each computer’s name you will see whether it is online or not. When a computer 
is online, it will receive transport and timecode signals, and its sequencer application 
can be started and stopped by remote control. If it is off-line, it can only be started 
from its own keyboard – it is effectively an independent machine, although it is still on 
the network.
ÖNote that any computer can control any and all of the others – VST System Link is a 
peer-to-peer network and there is no absolute “master” computer.
Receiving and Sending 
indicators 
						

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SynchronizationActivating VST System Link
To put all computers online, proceed as follows:
1.For all computers, activate the Online checkbox on the VST System Link page. 
2.Start playback on one computer to check that the system is working – all 
computers should start almost instantly and play perfectly in time, with sample-
accurate precision.
•The Offset Samples setting allows you to adjust whether one machine will play 
slightly ahead or behind the rest.
This is normally not needed, but occasionally with some hardware you may find 
that the lock is a few samples out. For now, leave it set to 0 – it will most likely be 
what you want.
•The Transfer Bits setting allows you to specify whether you want to transfer 24 or 
16 bits. This allows you to use older audio cards which do not support transfer of 
24 bits.
VST System Link sends and understands all transport commands (such as play, stop, 
fast forward, rewind, etc.). This allows you to control the entire network from one 
computer without a problem – try it! If you jump to a locator point on one machine, all 
other machines will also instantly jump to that locator point.
Scrubbing via VST System Link
You can scrub on one computer and have the video and audio on another computer 
scrub along. However, the playback on the linked systems may not be perfectly in 
sync while scrubbing and there are some further restrictions you should bear in mind 
when scrubbing via VST System Link:
•Use the jog/shuttle control on the Transport panel or a remote controller for 
scrubbing.
Scrubbing with the Scrub tool does not work over a VST System Link connection.
•Always use the system where you started scrubbing to control the scrubbing, e. g. 
change the scrub speed or stop scrubbing.
Changing the scrub speed on a remote system will only change the speed on the 
local system.
•You can start playback on all systems.
This stops scrubbing and enters playback on all systems in sync.
Using MIDI
As well as supplying transport and sync control, VST System Link also supplies up to 
16 MIDI ports, with 16 channels each. To set this up, proceed as follows:
1.Use the MIDI Inputs and MIDI Outputs value fields to specify the number of MIDI 
ports you need.
The default value is 0 MIDI In and 0 MIDI Out ports.
2.In the Project window, create a MIDI track and open the Inspector (top section).
!Make sure that all computers have their tempos set to the same value, otherwise your 
synchronization will be seriously skewed. 
						

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SynchronizationActivating VST System Link
3.If you now open the Input or Output Routing pop-up menu, you will find the 
specified System Link ports added to the list of MIDI inputs or outputs.
This allows you to route MIDI tracks to VST instruments running on another computer, 
as described in the application examples (see 
“Using one computer for VST 
instruments” on page 668).
The “Use Selected ASIO Ports for Data only” setting
If you are sending huge amounts of MIDI data at once, there is a small possibility that 
you might run out of bandwidth on your VST System Link network. This will manifest 
itself by notes “choking” or timing becoming erratic.
If this happens, you can devote more bandwidth to MIDI by activating the “Use 
Selected ASIO Ports for Data only” option on the VST System Link page of the 
Device Setup dialog. When this is activated, the VST System Link information will be 
sent on the entire channel instead of just one bit, more than enough for all the MIDI 
you could ever hope to use. The downside is that you can no longer use this ASIO 
channel for audio transfer (do not connect it to a speaker!), thus leaving you with only 
7 audio channels in our ADAT cable example. Depending on how you work, this might 
be a reasonable compromise.
Hearing the network audio
If you are using an external mixing desk, hearing your audio really is not an issue – just 
plug the outputs of each computer into the desired channels on the external mixing 
desk, start playback on one of the computers, and you are good to go.
However, many people prefer to mix internally inside the computer and just use a desk 
for monitoring (or maybe not use any external mixer at all). In this case you will need to 
select one computer to be your “main mix computer” and send the audio from your 
other computers into this.
In the following example, we assume you are using two computers, with computer 1 
as your main mix computer and computer 2 running two additional stereo audio 
tracks, an FX channel track with a reverb plug-in and a VST instrument plug-in with 
stereo outputs. 
						

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SynchronizationActivating VST System Link
Proceed as follows:
1.Set things up so that you can listen to the audio playback from computer 1.
In other words, you need an unused set of outputs, e. g. an analog stereo output, 
connected to your monitoring equipment.
2.On computer 2, route each of the two audio tracks to a separate output bus.
These should be busses connected to the digital outputs – let’s call them Bus 1 
and 2.
3.Route the FX channel track to another VST System Link bus (Bus 3).
4.Route the VST instrument channel to yet another bus (Bus 4).
5.Go back to computer 1 and check the corresponding four VST System Link input 
busses.
If you start playback on computer 2, the audio should “appear” on the input busses 
on computer 1. However, to mix these audio sources you need actual mixer 
channels.
6.Add four new stereo audio tracks on computer 1 and route these to the output bus 
you use for listening, e.
 g. to the analog stereo outputs.
7.For each of the audio tracks, select one of the four input busses.
Now, each computer 2 bus is routed to a separate audio channel on computer 1.
8.Activate monitoring for the four tracks.
If you now start playback, the audio from computer 2 will be sent “live” to the new 
tracks on computer 1, allowing you to hear them together with any tracks you play 
back on computer 1.
For more information about Monitoring, see “About monitoring” on page 31.
Adding more tracks
What if you have more audio tracks than you have VST System Link busses (physical 
outputs)? Then you just use the computer 2 mixer as a submixer: Route several audio 
channels to the same output bus and adjust the output bus level if needed.
ÖIf your audio cards have multiple sets of input and output connections, you can link up 
multiple ADAT cables and send audio via any of the busses on any of the cables.
Internal mixing and latency
One problem with mixing inside the computer is the latency issue we mentioned 
earlier. The VST engine always compensates for record latencies, but if you are 
monitoring through computer 1 you will hear a processing delay while you listen to 
signals coming from your other computers (not on your recording!). If your audio card 
in computer 1 supports ASIO Direct Monitoring you should definitely turn this on. You 
can find the setting on the VST Audio System device panel for your hardware (see 
“ASIO Direct Monitoring” on page 119). Most modern ASIO cards support this 
function. If yours does not, you may want to change the Offset Samples value on the 
VST System Link page to compensate for any latency issues. 
						

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SynchronizationActivating VST System Link
Setting up a larger network
Setting up a larger network is not much more difficult than a two-computer network. 
The main thing to remember is that VST System Link is a daisy chain system. In other 
words, the output of computer 1 goes to the input of computer 2, the output of 
computer 2 goes to the input of computer 3, and so on around the chain. The output 
of the last computer in the chain must always go back into the input of computer 1, to 
complete the ring.
Once you have done this, the transmission of all the transport, sync, and MIDI 
information to the whole network is handled pretty much automatically. However, 
where you may run into confusion in a large network is in the transmission of audio 
signals back to a central mix computer.
If you have lots of hardware inputs and outputs on your ASIO cards, you do not have 
to send audio via the chain at all, but can transmit it directly to the master mix 
computer via one or more of its other hardware inputs. For example, if you have a 
Nuendo Digiset interface or 9652 card on computer 1, you could use ADAT cable 1 
for networking, ADAT cable 2 as a direct audio input from computer 2, and ADAT 
cable 3 as a direct audio input from computer 3.
You can also transmit audio via the ring system if you do not have enough hardware I/Os 
for direct audio transmission. For example, in a four-computer scenario you could send 
audio from computer 2 into a channel in the mixer in computer 3, from there to a channel 
in the mixer in computer 4, and from there back to the master mixer in computer 1. This 
can certainly be tricky to set up, so for complex networks it is generally recommended to 
use ASIO cards with at least three separate digital I/Os. 
Application examples
Using one computer for VST instruments
In this example, one computer will be used as main record and playback machine, and 
another computer as a virtual synth rack. Proceed as follows:
1.Record a MIDI track into computer 1.
2.Once you have finished recording, route the MIDI output of that track to VST 
System Link MIDI port 1.
3.On computer 2, open up the VST Instruments window and assign an instrument to 
the first slot in the rack.
4.Route the VST instrument channel to the desired output bus.
If you are using computer 1 as your main mixing computer, this would be one of the 
VST System Link output busses, connected to computer 1.
5.Create a new MIDI track in the Project window of computer 2 and assign the MIDI 
output of the track to the VST instrument you created. 
6.Assign the MIDI input of the track to be VST System Link port 1.
Now, the MIDI track on computer 1 is routed to the MIDI track on computer 2, 
which in turn is routed to the VST instrument.
7.Now activate monitoring for the MIDI track on computer 2, so that it will listen and 
respond to any MIDI commands coming in.
In Cubase, click the Monitor button in the track list or Inspector.
8.Start playback on computer 1.
It will now send the MIDI information on the track to the VST instrument loaded on 
computer 2. 
						

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SynchronizationActivating VST System Link
Even with a slow computer you should be able to stack a whole bunch of extra VST 
instruments this way, expanding your sound palette considerably. Do not forget that 
VST System Link MIDI is also sample-accurate, and thus has much tighter timing than 
any hardware MIDI interface ever invented!
Creating a virtual effect rack
The effect sends for an audio channel in Cubase can either be routed to an FX 
channel track or to any activated group or output bus. This allows you to use a 
separate computer as a “virtual effect rack”, by setting the system up as follows:
1.On computer 2 (the machine you will use as effect rack), add a new stereo audio 
track.
You cannot use an FX channel track in this case, since the track must have an 
audio input.
2.Add the desired effect as an insert effect for the track.
Let’s say you add a high-quality reverb plug-in.
3.In the Inspector, select one of the VST System Link busses as input for the audio 
track.
You want to use a separate VST System Link bus, which will only be used for this 
purpose.
4.Route the channel to the desired output bus.
If you are using computer 1 as your main mixing computer, this would be one of the 
VST System Link output busses, connected to computer 1.
5.Activate monitoring for the track.
6.Go back to computer 1 and select a track to which you want to add some reverb.
7.Bring up the effect sends for the track in the Inspector or the MixConsole.
8.Open the Send Routing pop-up menu for one of the sends and select the VST 
System Link bus assigned to the reverb in step 3.
9.Use the Send slider to adjust the amount of effect as usual.
The signal will be sent to the track on computer 2 and processed through its insert 
effect, without using any processor power on computer 1.
You can repeat the steps above to add more effects to the “virtual effect rack”. The 
number of effects available this way is only limited by the number of ports used in the 
VST System Link connection (and of course by the performance of computer 2, but 
given that it will not have to handle any recording or playback, you should be able to 
use quite a lot of effects).
Getting extra audio tracks
All computers on a VST System Link network are locked with sample-accuracy. 
Therefore, if you find that the hard drive on one computer is not fast enough to run as 
many audio tracks as you need, you can record new tracks on one of the other 
computers instead. This would create a “virtual RAID system”, with several disks all 
operating together. All tracks will remain locked together just as tightly as if they were 
all running on the same machine. This means that you effectively have an unlimited 
track count! Need another 100 tracks? Just add another computer.
Dedicated Video Playback
Playback of high-resolution video can be taxing on a system’s CPU. By dedicating 
one computer for video playback via System Link, you can free up resources on your 
main CPU for audio and MIDI processing. Since all transport commands will respond 
on the VST System Link computers, scrubbing video is possible even when it is 
coming from another computer.  
						

							670
Video
Introduction
Cubase supports the integration of video files in your project. You can play back video 
files in various formats and via different output devices from within Cubase, edit your 
music to the video, extract the audio material from a video file, and replace the audio 
later with different audio material.
Before you start
When working on a project involving a video file, you first need to set up your system 
according to your equipment and your demands. The following sections provide some 
general information about video file formats, frame rates, and video output devices. 
Video file compatibility
Because there are many types of video files, it can be difficult to determine if one will 
work on your system. There are two ways to figure out if Cubase can play back a 
certain video file:
•Open the video file with QuickTime 7.1 or higher, because Cubase uses 
QuickTime for playing back video files.
•Check the file information of a video file in the Pool. If the information reads “Invalid 
or not supported file!”, the video file is either corrupt or the format is not supported 
by the available codecs.
Video container formats
Video and other multi-media files come in a container format. This container holds 
various streams of information including video and audio, but also metadata such as 
synchronization information required to play back audio and video together. Data 
regarding creation dates, authors, chapter markings, and more can also be held within 
the container format. 
The following container formats are supported by Cubase:
!If you are not able to load a certain video file, you must use an external application to 
convert the file into a compatible format or install the required codec. For more 
information on codecs, see the section 
“Codecs” on page 671.
FormatDescription
MOVThis is a QuickTime movie.
QTThis is also a QuickTime movie, but it is only used on Windows systems.
MPEG-1This is the first standard of the Moving Picture Experts Group for video 
and audio compression, used for making video CDs. Files of this 
container format can have the extensions “.mpg” or “.mpeg”.
MPEG-4This format is based on the QuickTime movie standard, can contain 
various metadata for streaming, editing, local playback, and interchange 
of content. Its file extension is “.mp4”.