Steinberg Nuendo 4 Manual

							11
VST Connections: Setting up input and output busses
About this chapter
Nuendo uses a system of input and output busses to trans-
fer audio between the program and the audio hardware.
 Input busses let you route audio from the inputs on your audio 
hardware into the program. This means that when you record 
audio, you will always do this through one or several input 
busses.
 Output busses let you route audio from the program to the 
outputs on your audio hardware. When you play back audio, 
you will always do this through one or several output busses.
As you can see, the input and output busses are vital when 
you work with Nuendo. This is why you find this chapter in 
the beginning of the Operation Manual – once you under-
stand the bus system and set up the busses properly, it will 
be easy to go on with recording, playing back, mixing and 
doing surround work.
Setting up busses
Strategies
You can create any number of busses in Nuendo, in virtu-
ally any channel configuration – mono, stereo or a number 
of surround formats.
ÖThe bus configuration is saved with the projects – 
therefore it’s a good idea to add and set up the busses 
you need and save these in a template project (see “Save 
as Template” on page 488).
When you start working on new projects, you start from this template. 
That way you get your standard bus configuration without having to make 
new bus settings for each new project. If you need to work with different 
bus configurations in different projects, you can either create several dif-
ferent templates or store your configurations as presets (see “Other bus 
operations” on page 14). The templates can of course also contain other 
settings that you regularly use – sample rate, record format, a basic track 
layout, etc.
So, which type of busses do you need? This depends on 
your audio hardware, your general audio setup (e.g. sur-
round speaker setup) and what kind of projects you work 
with. Here’s an example:
Let’s say you are using audio hardware with eight analog 
inputs and outputs and digital stereo connections (10 in-
puts and outputs all in all). Furthermore, you work with a 
surround setup in 5.1 format. Here’s a list of busses you 
may wish to add:
Input busses
 Most likely you need at least one stereo input bus assigned to 
an analog input pair. This would let you record stereo material. 
If you want to be able to record in stereo from other analog in-
put pairs as well, you could add stereo input busses for these 
too.
 Although you can record mono tracks from one side of a ste-
reo input, it may be a good idea to add a dedicated mono in-
put bus. This could be assigned to an analog input to which 
you have connected a dedicated microphone pre-amp for ex-
ample. Again, you can have several different mono busses.
 You probably want a dedicated stereo input bus assigned to 
the digital stereo input, for digital transfers.
 If you want to transfer surround material directly to a surround 
track, e.g. from surround-configured location recording equip-
ment, you need an input bus in that surround format  – in this 
example, this would be a 5.1 input bus.
Output busses
 You will need one or several stereo output busses for routing 
stereo mixes to master recorders or other destinations.
 For digital transfers, you need a stereo bus assigned to a dig-
ital stereo output as well.
 You need a surround bus in the format of your speaker config-
uration (in this example, 5.1) assigned to the correct outputs 
(which in turn are connected to the correct speakers).
 You may want additional surround busses if you tend to work 
in different surround formats. 
						

							12
VST Connections: Setting up input and output busses
Preparations
Before you set up busses, you should name the inputs 
and outputs on your audio hardware. For example, if you 
are using a 5.1 surround speaker setup, you should name 
the outputs according to which speaker they are con-
nected to (Left, Right, Center and so on). 
The reason for this is compatibility – it makes it easier to 
transfer projects between different computers and setups. 
For example, if you move your project to another studio, 
the audio hardware may be of a different model. But if 
both you and the other studio owner have given your in-
puts and outputs names according to the surround setup 
(rather than names based on the audio hardware model), 
Nuendo will automatically find the correct inputs and out-
puts for your busses and you will be able to play and 
record without having to change the settings.
Use the Device Setup dialog to assign names to the in-
puts and outputs of your audio hardware:
1.Open the Device Setup dialog from the Devices menu.
2.Make sure that the correct driver for your audio hard-
ware is selected on the VST Audio System page, so that 
the audio card is listed in the Devices list.
3.Select your audio card in the list.
The available input and output ports on your audio hardware are listed on 
the right.
4.To rename a port, click its name in the “Show as” col-
umn and enter a new name.
•If needed, you can also disable ports by deactivating 
them in the “Visible” column.
Disabled ports won’t show up in the VST Connections window when you 
are making bus settings. If you attempt to disable a port that is used by a 
bus, you will be asked whether this is really what you want – note that 
this will remove the port from the bus!
5.Click OK to close the Device Setup dialog.
ÖIf you open a project created on another computer and 
the port names don’t match (or the port configuration isn’t 
the same – e.g. the project is created on a system with 
multi-channel i/o and you open it on a stereo in/out sys-
tem), the Pending Connections dialog will appear.
This allows you to manually re-route ports used in the project to ports 
available in your system.
The VST Connections window
You add and set up busses in the VST Connections win-
dow, opened from the Devices menu.
This window contains the following tabs:
 The Inputs and Outputs tabs are for viewing input busses or 
output busses, respectively. 
 The Group/FX tab allows you to create Group and FX chan-
nels/tracks and to make output assignments for these. See 
“Setting up Groups and FX channels” on page 17. 
 The External FX tab allows you to create effect send/return 
busses for connecting external effects which can then be se-
lected via the effect pop-up menus from inside the program. 
See “External instruments/effects” on page 17 and “Using ex-
ternal effects” on page 182 for further information.
 The External Instruments tab allows you to create input/output 
busses for connecting external instruments. See “External in-
struments/effects” on page 17 and the chapter “VST Instru-
ments and Instrument tracks” on page 189 for further 
information.
 The Studio tab is where you enable and configure the Control 
Room. See the chapter “Control Room” on page 151.
For the time being, we shall focus on how to set up input 
and output busses. 
						

							13
VST Connections: Setting up input and output busses
Depending on which tab you have selected, Inputs or Out-
puts, the window lists the current input or output busses, 
with the following columns:
Adding a bus
1.Click the Inputs or Outputs tab depending on which 
you want to add.
2.Click the Add Bus button.
A dialog appears.
3.Select the desired (channel) configuration.
The pop-up menu contains Mono and Stereo options as well as several 
surround formats. To select another surround format, use the “More…” 
submenu.
Alternatively you can right-click in the VST Connections 
window and add a bus in the desired format directly from 
the context menu that appears.
The new bus appears with the ports visible.
4.Click in the Device Port column to select an input/out-
put port for a channel in the bus.
The pop-up menu that appears lists the ports with the names you have as-
signed in the Device Setup dialog. Repeat this for all channels in the bus.
Adding a child bus
A surround bus is essentially a set of mono channels – 6 
channels in the case of 5.1 format. If you have a mono 
track in the project, you can route it to a separate speaker 
channel in the bus (or route it to the whole surround bus 
and use the surround panner to position it in the surround 
image). But what if you have a stereo track that you simply 
want to route to a stereo channel pair within the bus (Left 
and Right or Left Surround and Right Surround for exam-
ple)? For this you need to create a child bus.
1.Select the surround bus in the list and right-click on it.
A pop-up menu appears.
2.Select a channel configuration from the “Add Child 
Bus” submenu.
As you can see, you can create stereo child busses (routed to various 
speaker channel pairs in the surround bus) or other surround bus formats 
(with fewer channels than the “parent bus”).
The child bus you created will be available for direct rout-
ing in the mixer. It’s a part of the parent surround bus, 
which means there will be no separate channel strip for it.
Although child busses are probably most useful in output 
busses, you can also create child busses within a sur-
round input bus – for example if you want to record a ste-
reo channel pair (e.g. front left-right) in the surround bus 
to a separate stereo track.
Column Description
Bus Name Lists the busses. You can select busses and rename 
them by clicking on them in this column.
Speakers Indicates the speaker configuration (mono, stereo, sur-
round formats) of each bus.
Audio Device This shows the currently selected ASIO driver.
Device Port When you have “opened” a bus (by clicking its + button in 
the Bus Name column) this column shows which physical 
input/output on your audio hardware is used by the bus.
Click You can route the click to a specific output bus, regard-
less of the actual Control Room output, or indeed when 
the Control Room is disabled.  
						

							14
VST Connections: Setting up input and output busses
Setting the Main Mix bus (the default output bus)
The Main Mix is the output bus that each new channel in 
the mixer will be assigned to when it is created.
Any one of the output busses in the VST Connections 
window can be the default output bus. By right-clicking on 
the name of an output bus, you can set this bus as the 
Main Mix bus.
Setting the default output bus in the VST Connections window.
When creating new audio, group or FX channels in the 
mixer, they will automatically be routed to the default bus.
Other bus operations
To change the port assignment for a bus, you proceed 
as when you added it – make sure the channels are visible 
(by clicking the “+” button next to the bus, or by clicking 
the “+ All” button at the top of the window) and click in the 
Device Port column to select ports.
To remove a bus you don’t need, select it in the list, 
right-click and select “Remove Bus” from the pop-up 
menu, or press [Backspace].
You can store and recall bus presets with the pop-up 
menu at the top of the window.
To store the current configuration as a preset, click the Store “+” button 
and enter a name for the preset. You can then select the stored configu-
ration directly from the Presets pop-up menu at any time. To remove a 
stored preset, select it and click the “-” button.
Using the busses
This section describes briefly how to use the input and out-
put busses you have created. For details refer to the chap-
ters “Recording” on page 64 and “The mixer” on page 122.
Routing
When you play back an audio track (or any other audio 
channel in the mixer – VST Instrument channels, ReWire 
channels, etc.), you route it to an output bus. In the same 
way, when you record on an audio track you select from 
which input bus the audio should be sent.
You can select input and output busses in the Inspec-
tor, using the Input and Output Routing pop-up menus.
For audio-related channel types other than audio track 
channels (i.e. VST Instrument channels, ReWire channels, 
Group channels and FX channels), only the Output Rout-
ing pop-up menu is available. Select one of its subtracks 
in the Track list to open it.
You can also select busses in the Routing panel at the 
top of each channel strip in the mixer.
Again, for VST Instrument channels, ReWire channels, Group channels 
and FX channels you will only be able to select output busses.
!The default bus is indicated by an orange colored 
speaker icon next to its name in the VST Connec-
tions window. 
						

							15
VST Connections: Setting up input and output busses
If you press [Alt]/[Option] and select an input or output 
bus in the Mixer Routing View, it will be chosen for all se-
lected channels.
This makes it easy to quickly set several channels to use the same input 
or output. Similarly, if you press [Shift] and select a bus, the following se-
lected channels will be set to use incrementing busses – the second se-
lected channel will use the second bus, the third will use the third bus 
and so on.
ÖIf the Routing panel isn’t shown, click the Show Rout-
ing button in the extended common panel or open the 
Mixer context menu and select “Show Routing View” from 
the Window submenu.
The “Show Routing” button in the extended common panel of the Mixer.
When selecting an input bus for a track you can only se-
lect busses that correspond to the track’s channel config-
uration. Here are the details for input busses:
 Mono tracks can be routed to mono input busses or individual 
channels within a stereo or surround input bus.
 Mono tracks can be routed to External Inputs that are config-
ured in the Studio tab of the VST Connections window. These 
can be mono or individual channels within a stereo or surround 
input bus. They can also be routed to the Talkback input.
 Mono tracks can also be routed to mono output busses, mono 
group output busses or mono fx channel output busses, pro-
vided that these will not lead to feedback.
 Stereo tracks can be routed to mono input busses, stereo in-
put busses or stereo child busses within a surround bus.
 Stereo tracks can be routed to External Inputs that are config-
ured in the Studio tab of the VST Connections window. These 
can be mono input busses or stereo input busses. They can 
also be routed to the Talkback input.
 Stereo tracks can also be routed to mono or stereo output 
busses, mono or stereo group output busses and mono or 
stereo fx channel output busses, provided that these will not 
lead to feedback.
 Surround tracks can be routed to surround input busses.
 Surround tracks can be routed to External Inputs that are con-
figured in the Studio tab of the VST Connections window, pro-
vided that these have the same input configuration.  Surround tracks can also be routed to output busses, provided 
that these have the same input configuration or will not lead to 
feedback.
For output busses any assignment is possible.
To disconnect input or output busses, select “No Bus” 
from the corresponding pop-up menu.
Viewing the busses in the mixer
In the mixer, busses are represented by input and output 
channels (shown in separate panes to the left and right in 
the window). You can show or hide these independently 
by clicking the Hide Input Channels and Hide Output 
Channels buttons in the common panel:
!Assignments that will lead to feedback are not avail-
able in the pop-up menu. This is also indicated by a 
one-way symbol.
Hide Input Channels
Hide Output Channels 
						

							16
VST Connections: Setting up input and output busses
Input channels
The input channels are shown to the left in the mixer. As 
you can see, each input channel resembles a regular mixer 
channel strip. Here you can do the following:
Check and adjust the recording level using the Input 
Gain knobs and/or the level fader.
See “Setting input levels” on page 69.
Change the phase of the input signal.
This is done by clicking the Input Phase button next to the Input Gain 
control.
Add effects or EQ to the input bus.
See “Recording with effects” on page 76 for an example of how to add 
effects to your recording at the input bus stage.
Output channels
The output channels are shown to the right in the mixer. 
Here you can do the following:
Adjust the output level for the busses with the faders.
Add effects or EQ.
These will affect the whole bus. Examples of effects you may want to add 
here include compressors, limiters and dithering. See the chapter “Audio 
effects” on page 168.
Using Sends, send varying amounts of one output bus 
to any other output bus that is to the right of the selected 
output bus in the mixer.
!The settings you make in the input channel strip will 
be a permanent part of the recorded audio file! 
						

							17
VST Connections: Setting up input and output busses
Setting up Groups and FX channels
The Group/FX tab in the VST Connections window shows 
all Group channels and FX channels in your project. You 
can create new Group or FX channels by clicking the cor-
responding Add button. This is the same as creating 
Group channel tracks or FX channel tracks in the Project 
window (see “Using group channels” on page 142 and 
the chapter “Audio effects” on page 168).
However, the VST Connections window also allows you to 
create child busses for Groups and FX Channels. This is 
useful e.g. if you have Groups or FX Channels in surround 
format and want to route stereo channels to specific chan-
nel pairs in these.
To create a child bus for a Group channel or FX channel in 
surround format, proceed as follows:
1.Open the VST Connection window and select the 
Groups/FX tab.
2.Select the Group or FX channel in the list and right-
click it.
3.Select a channel configuration from the “Add Child 
Bus” submenu.
The child bus you created will be available for direct rout-
ing in the mixer. It’s a part of the parent Group or FX chan-
nel, which means there will be no separate channel strip 
for it.
About monitoring
By default, monitoring is done via the Control Room (see 
the chapter “Control Room” on page 151). When the 
Control Room is disabled on the Studio tab of the VST 
Connections window, the Main Mix bus (see “Setting the 
Main Mix bus (the default output bus)” on page 14) will be 
used for monitoring.
Setting the monitoring level
When you are using the Control Room for monitoring, this 
is set in the Control Room Mixer, see the chapter “Control 
Room” on page 151. When you are monitoring via the 
Main Mix bus, you can adjust the monitoring level in the 
regular Project Mixer.
When auditioning or scrubbing in the Sample Editor, you 
can also set the monitoring level using the small fader on 
the Sample editor toolbar.
External instruments/effects
Nuendo supports the integration of external effect devices 
and external instruments, e. g. hardware synthesizers, into 
the sequencer signal flow.
You can use the External Instruments tab and the External 
FX tab in the VST Connections window to define the 
necessary send and return ports and access the instru-
ments/effects through the VST Instruments window.
Requirements
To use external effects, you need audio hardware with 
multiple inputs and outputs. To use external instruments, a 
MIDI interface must be connected to your computer.
An external effect will require at least one input and one output (or input/
output pairs for stereo effects) – in addition to the input/output ports you 
use for recording and monitoring.
As always, audio hardware with low-latency drivers is a 
good thing to have.
Nuendo will compensate for the input/output latency and ensure that the 
audio processed through external effects isn’t shifted in time.
!External Instruments and effects are indicated by an 
“x” icon in the list next to their names in the respec-
tive pop-up menus. 
						

							18
VST Connections: Setting up input and output busses
Connecting the external effect/instrument
To set up an external effect or instrument, proceed as fol-
lows:
1.Connect an unused output pair on your audio hard-
ware to the input pair on your external hardware device.
In this example, we assume that the hardware device has stereo inputs 
and outputs.
2.Connect an unused input pair on your audio hardware 
to the output pair on your hardware device.
Once the external device is connected to the audio hard-
ware of your computer, you have to set up the input/out-
put busses in Nuendo
Setting up external effects
1.Open the VST Connections window from the Devices 
menu.
2.Open the External FX tab and click “Add External FX”.3.In the dialog that appears, enter a name for the exter-
nal effect and specify the Send and Return configurations. 
If you want to set up a MIDI device corresponding to the 
external effect, click the “Associate MIDI Device” button.
Depending on the type of effect, you can specify mono, stereo or surround 
configurations. When clicking “Associate MIDI Device”, you can use the 
MIDI Device Manager functions to create a new MIDI device for the effect. 
Note that delay compensation will only be applied for the effect when you 
use MIDI devices. For information about the MIDI Device Manager and 
user device panels see the separate PDF document “MIDI Devices”.
4.Click OK. This adds a new External FX bus.
5.Click in the Device Port column for the Send Bus 
“Left” and “Right” ports and select the outputs on your au-
dio hardware that you connected in step 1 above.
6.Click in the Device Port column for the Return Bus 
“Left” and “Right” ports and select the inputs on your au-
dio hardware that you connected in step 2 above.
7.If you like, make additional settings for the bus.
These are found in the columns to the right. Note however that you can 
adjust these while actually using the external effect – which may be eas-
ier as you can hear the result. You have the following options:
!Please note that it is possible to select input/output 
ports for external effects/instruments that are already 
used (i.e. that have been selected as inputs/outputs 
in the VST Connections window). If you select a 
used port for an external effect/instrument, the exist-
ing port assignment will be broken. Note that you will 
not get a warning message!
Setting Description
Delay If your hardware effect device has an inherent delay (la-
tency), you should enter this value here, as it allows Nu-
endo to compensate for that delay during playback. You 
can also let the delay value be determined by the pro-
gram by right-clicking in the Delay column for the effect 
and selecting “Check User Delay”. Note that you don’t 
have to take the latency of the audio hardware into ac-
count – this is handled automatically by the program.
Send Gain Allows you to adjust the level of the signal being sent to 
the external effect.
Return Gain Allows you to adjust the level of the signal coming in from 
the external effect. 
Note however that excessive output levels from an external 
effect device may cause clipping in the audio hardware. 
The Return gain setting cannot be used to compensate for 
this – you have to lower the output level on the effect de-
vice instead.
MIDI Device When you click in this column, a pop-up menu opens 
where you can either disconnect the effect from the as-
sociated MIDI device, select a MIDI device, create a new 
device or open the MIDI Device Manager in Nuendo to 
edit the MIDI device. 
When Studio Manager 2 is installed, you may also select 
an OPT editor to access your external effect.
Used Whenever you insert an external effect into an audio 
track, this column shows a check mark (“x”) to indicate 
that the effect is being used. 
						

							19
VST Connections: Setting up input and output busses
8.When you are done, close the VST Connections win-
dow.
ÖNote that external device ports are exclusive, see 
“Connecting the external effect/instrument” on page 18.
How to use the external effect
If you now click an insert effect slot for any channel and 
look at the effect pop-up menu, you will find the new exter-
nal FX bus listed on the “External Plug-ins” submenu.
When you select it, the following happens:
 The external FX bus is loaded into the effect slot just like a 
regular effect plug-in.
 The audio signal from the channel will be sent to the outputs 
on the audio hardware, through your external effect device and 
back to the program via the inputs on the audio hardware.
 A parameter window appears, showing the Delay, Send Gain 
and Return Gain settings for the external FX bus. You can ad-
just these as necessary while playing back. The parameter 
window also provides the “Measure Effect’s Loop Delay for 
Delay Compensation” button. This is the same function as the 
“Check User Delay” option in the VST Connections window. It 
provides Nuendo with a Delay value to be used for delay com-
pensation. When you have defined a MIDI device for the ef-
fect, the corresponding Device window will be opened. When 
Studio Manager 2 is installed, and you have set up a corre-
sponding OPT editor, this OPT editor will be displayed.
The default parameter window for an external effect
Like any effect, you can use the external FX bus as an in-
sert effect or as a send effect (an insert effect on an FX 
channel track). You can deactivate or bypass the external 
effect with the usual controls.
Setting up external instruments
1.Open the VST Connections window from the Devices 
menu.
2.Open the External Instrument tab and click “Add Ex-
ternal Instrument”.
3.In the dialog that appears, enter a name for the exter-
nal instrument and specify the number of required mono 
and/or stereo returns. If you want to set up a MIDI device 
corresponding to the external instrument, click the Associ-
ate MIDI Device button.
Depending on the type of instrument, a specific number of mono and/or 
stereo return channels is required. When clicking “Associate MIDI De-
vice”, you can use the MIDI Device Manager functions to create a new 
MIDI device. For information about the MIDI Device Manager and user 
device panels see the separate PDF document “MIDI Devices”.
4.Click OK. This adds a new external instrument bus.
5.Click in the Device Port column for the Return Bus 
“Left” and “Right” ports and select the inputs on your audio 
hardware to which you connected the external instrument.
6.If you like, make additional settings for the bus.
These are found in the columns to the right. Note however that you can 
adjust these while actually using the external instrument – which may be 
easier as you can hear the result. You have the following options:
Setting Description
Delay If your hardware device has an inherent delay (latency), 
you should enter this value here. This allows Nuendo to 
compensate for that delay during playback. Note that you 
don’t have to take the latency of the audio hardware into 
account – this is handled automatically by the program.
Return Gain Allows you to adjust the level of the signal coming in from 
the external instrument. 
Note however that excessive output levels from an exter-
nal device may cause clipping in the audio hardware. The 
Return gain setting cannot be used to compensate for 
this – you have to lower the output level on the device in-
stead. 
						

							20
VST Connections: Setting up input and output busses
7.When you are done, close the VST Connections win-
dow.
ÖNote that external device ports are exclusive, see 
“Connecting the external effect/instrument” on page 18.
How to use the external instrument
Once you have set up the external instrument in the VST 
Connections window, you can use it as a VST Instrument. 
Open the VST Instruments window and click on an empty 
instrument slot. In the instrument pop-up menu, your ex-
ternal instrument is listed on the External Instruments sub-
menu:
When you select the external instrument in the VST Instru-
ments window, the following happens:
 A parameter window for the external device is opened auto-
matically. This may either be the Device window, allowing you 
to create a generic device panel, an OPT editor window or a 
default editor. For information about the Device window, the 
MIDI Device Manager and User device panels, see the sepa-
rate PDF document “MIDI Devices”. To send MIDI notes to the external instrument, open the out-
put pop-up menu in the Inspector for the corresponding MIDI 
track and select the MIDI device to which the external instru-
ment is connected. This ensures use of delay compensation. 
The instrument will now play any MIDI notes it receives from 
this track and return them to Nuendo through the return chan-
nel(s) you have set up. 
The external instrument will behave like any other VST In-
strument in Nuendo.
About the Favorites buttons
In the VST Connections window, both the External FX tab 
and the External Instruments tab feature a Favorites button.
The Favorites button on the External FX tab
Favorites are device configurations that you can recall at 
any time, like a library of external devices that are not con-
stantly connected to your computer. They also allow you 
to save different configurations for the same device, e. g. a 
multi-effect board or an effect that provides both a mono 
and a stereo mode.
To save a device configuration as a favorite, proceed as 
follows:
When you have added a new device in the VST Con-
nections window, select it in the Bus Name column and 
click the Favorites button.
A context menu is displayed showing an option to add the selected ef-
fect or instrument to the Favorites.
You can recall the stored configuration at any time by 
clicking the Favorites button and selecting the device 
name from the context menu.
MIDI Device When you click in this column, a pop-up menu opens 
where you can either disconnect the instrument from the 
associated MIDI device, select a MIDI device, create a 
new device or open the MIDI Device Manager in Nuendo 
to edit the MIDI device. 
When Studio Manager 2 is installed, you may also select 
an OPT editor to access your external instrument.
Used Whenever you insert the external instrument into a VST 
Instrument slot, this column shows a chicanery (“x”) to in-
dicate that the instrument is being used. Setting Description