Focusrite Scarlett 4i4 User manual

User Guide
focusrite.comVersion 2

2
TABLE OF CONTENTS
OVERVIEW..................................................................... 3
Introduction .................................................................3
Features ....................................................................3
Box Contents ................................................................4
System requirements .........................................................4
GETTING STARTED ............................................................. 5
Quick Start Tool ..............................................................5
Mac users only:.................................................................5
Windows only:..................................................................7
All users:......................................................................9
Manual Registration.............................................................9
Audio Setup in your DAW......................................................10
Loopback Inputs ...............................................................11
Examples of Usage ..........................................................12
Connecting a microphone or instrument ...........................................12
Using Direct Monitoring.........................................................13
Connecting Scarlett 4i4 to loudspeakers ...........................................13
Creating an effects loop .........................................................15
Connecting Scarlett 4i4 to a DJ mixer..............................................16
HARDWARE FEATURES......................................................... 17
Front Panel.................................................................17
Back Panel .................................................................18
CHANNEL LISTINGS ...........................................................19
Performance Specications ...................................................20
Physical and Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
TROUBLESHOOTING ...........................................................23
COPYRIGHT AND LEGAL NOTICES ................................................23

3
OVERVIEW
Introduction
Thank you for purchasing this Third Generation Scarlett 4i4, one of the family of Focusrite professional
computer audio interfaces incorporating high quality Focusrite analogue preamps. You now have a
simple and compact solution for routing high quality audio to and from your computer and you will
also be able to download some exciting new software plug-ins once you’ve registered the product.
In developing the Third Generation series of Scarlett interfaces, we have made further improvements
to both performance and features. Audio specications have been upgraded throughout the unit to
give you greater dynamic range and even lower noise and distortion; additionally, the mic preamp now
accepts higher input levels. An important enhancement is the inclusion of Focusrite’s AIR function.
Individually selectable on Inputs 1 and 2, AIR subtly modies the preamp’s frequency response to
model the sonic characteristics of our classic transformer-based ISA microphone preamps. When
recording with good quality microphones, you will notice an enhanced clarity and denition in the
important mid to high frequency range, just where it is most needed for vocals and many acoustic
instruments. Third Generation Scarlett interfaces are class compliant on macOS: this means they
are plug-and-play, so no need to install a driver if you are a Mac user.
This User Guide provides a detailed explanation of the hardware to help you achieve a thorough
understanding of the product’s operational features. We recommend both users who are new to
computer-based recording, as well as more experienced users, take the time to read through the
User Guide so you are fully aware of all the possibilities the Scarlett 4i4 and accompanying software
has to offer. If the main User Guide sections do not provide the information you need, be sure to
consult support.focusrite.com, which contains a comprehensive collection of answers to common
technical support queries.
Features
The Scarlett 4i4 hardware interface provides the means for connecting microphones, musical
instruments or line level audio signals to a computer running Mac OS or Windows. The signals at the
physical inputs can be routed to your audio recording software / digital audio workstation (referred
to throughout this User Guide as the “DAW”) at up to 24-bit, 192 kHz resolution; similarly, the DAW’s
monitor or recorded output will appear at the unit’s physical outputs.
Audio sources – mics, instruments, etc. - connected to the physical inputs can be recorded in the
DAW and routed from your DAW to the physical outputs. The 4i4 is equipped with four audio output
channels, which can be connected to an amplier and speakers, powered monitors, headphones, DJ
or other type of analogue mixer, or any other analogue audio equipment you wish to use. Although
all inputs and outputs on the Scarlett 4i4 are routed directly to and from your DAW for recording and
playback, you can congure the routing within the 4i4’s accompanying Focusrite Control application
To meet your needs. The 4i4 also acts as a convenient MIDI interface between your computer and
other MIDI equipment.
For DJs, the four analogue outputs make it possible to have a stereo main output and a headphone
cue channel when mixing internally on a laptop; alternatively you have two separate stereo outputs
at your disposal for connection to an analogue DJ mixer.

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Box Contents
Along with your Scarlett 4i4 you should have:
• USB cable, Type ‘A’ to Type ‘C’
• Getting Started Information (printed inside the box lid)
• Important Safety Information
System requirements
The easiest way to check your computer’s operating system (OS) is compatible with your Scarlett is
to use our Help Centre’s compatibility articles:
support.focusrite.com/hc/categories/200693655
As new OS versions become available over time, you can continue to check for further compatibility
information by searching our Help Centre at support.focusrite.com.

5
GETTING STARTED
With the Third Generation, Scarlett interfaces introduce a new, faster way of getting up and running,
using the Scarlett Quick Start tool. All you need to do is connect your Scarlett 4i4 to your computer.
Once connected, you will see the device is recognised by your PC or Mac and the Quick Start tool will
guide you through the process from there.
IMPORTANT: The Scarlett 4i4 has a single USB 2.0 Type C port (on the rear panel): connect it to
your computer using the USB cable provided. The Scarlett 4i4 3rd Gen requires 900mA of power
for complete operation. All USB 3.0 and most USB 2.0 ports are capable of providing this level of
current.
If you are not sure if your computer’s USB 2.0 port can supply this level of current, please contact
your computer’s manufacturer for more information.
Your computer will initially treat your Scarlett as a Mass Storage Device (MSD), and during its rst
connection, the Scarlett will be in “Easy Start mode”
Quick Start Tool
We have tried to make registering your Scarlett 4i4 as simple as possible. The steps are designed to
be self explanatory, but we have described each step below, so you can see how they should appear
on either a PC or a Mac.
Mac users only:
On connecting your Scarlett 4i4 to your Mac, a Scarlett icon will appear on the desktop:

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Double-click on the icon to open the Finder window shown below:
Double-click on the “Click Here to Get Started.url” icon. This will redirect you to the Focusrite website,
where we recommend you register your device:
Click on “Let’s get you started”, and you’ll see a form which will be partly prelled for you automatically.
When you submit the form, you’ll see options to go straight to the downloads to get the software for
your Scarlett, or to follow a step by step setup guide based on how you want to use your Scarlett.
Once you have installed the Focusrite Control software to set up and congure your interface, the
Scarlett will be switched out of Easy Start mode so it no longer appears as a Mass Storage Device
when connected to your computer.
Your OS should switch the computer’s default audio inputs and outputs to the Scarlett. To verify this,
go to System Preferences > Sound, and ensure the input and output are set to Scarlett 4i4.
For detailed setup options on a Mac, open Applications > Utilities > Audio MIDI Setup.

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Windows only:
On connecting your Scarlett 4i4 to your PC, a Scarlett icon will appear on the desktop:
(Note that the drive letter may be something other than E:, depending on other devices connected
to your PC).
Double-click on the pop-up message to open the dialogue box shown below:
Double-click on “Open folder to view les”: this will open an Explorer window:

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Double-click “Click Here to Get Started”. This will redirect you to the Focusrite website, where we
recommend you register your device:
Click on “Let’s get you started”, and you’ll see a form which will be partly prelled for you automatically.
When you submit the form, you’ll see options to go straight to the downloads to get the software for
your Scarlett, or to follow a step by step setup guide based on how you want to use your Scarlett.
Once you have installed the Focusrite Control software to set up and congure your interface, the
Scarlett will be switched out of Easy Start mode so it no longer appears as a Mass Storage Device
when connected to your computer.
Your OS should switch the computer’s default audio inputs and outputs to be the Scarlett. To verify
this, right click on the Sound icon on the taskbar and select Sound Settings, and set the Scarlett
as the Input and Output Device.

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All users:
Note that a second le - “More Info & FAQs” - is also available during the initial set-up process. This
le contains some additional information about the Focusrite Quick Start tool which you may nd
helpful if you have any issues with the procedure.
Once registered, you will have immediate access to the following resources:
• Focusrite Control (Mac and Windows versions available) - see NOTE below
• Multi-language User Guides
You can nd the licence codes and links for the optional bundled software in your Focusrite account.
To nd out what bundled software is included with Scarlett 3rd generation, please visit our website:
focusrite.com/scarlett
NOTE: Installing Focusrite Control will also install the correct driver for your device. Focusrite Control
is available to download at any time, even without registering: see “Manual Registration” below.
Manual Registration
If you decide to register your Scarlet at a later date you can do so at:
customer.focusrite.com/register
You will need to enter the Serial Number manually: this number can be found on the base of the
interface itself, and also on the barcode label on the side of the box.
We recommend you download and install our Focusrite Control application, as this will disable Easy
Start mode and unlock the full potential of the interface. Initially, when in Easy Start mode, the
interface will function at sample rates up to 48 kHz and the MIDI I/O is disabled. Once Focusrite
Control is installed on your computer, you can work at sample rates up to 192 kHz.
If you decide not to download and install Focusrite Control immediately, it can be downloaded at any
time from:
customer.focusrite.com/support/downloads
To force your Scarlett out of Easy Start mode without rst registering it, connect it to your computer
and press and hold the 48V button for ve seconds. This will ensure your Scarlett has full functionality.
Please bear in mind that should you wish to register your Scarlett after taking this action, you will
need to so manually, as explained above.

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Audio Setup in your DAW
The Scarlett 4i4 is compatible with any Windows-based DAW that supports ASIO or WDM and any
Mac-based DAW that uses Core Audio. After following the Getting Started procedure described
above, you can start using the Scarlett 4i4 with the DAW of your choice.
To allow you to get started if you do not already have a DAW application installed on your computer,
both Pro Tools | First and Ableton Live Lite are included; this will be available to you once you’ve
registered your Scarlett 4i4. If you need help installing either DAW, please visit our Getting Started
pages at focusrite.com/get-started, where Getting Started videos are available.
Operating instructions for Pro Tools | First and Ableton Live Lite are beyond the scope of this User
Guide, but both applications include a full set of Help les. Instructions are also available at avid.com
and ableton.com respectively.
Please note - your DAW may not automatically select the Scarlett 4i4 as its default I/O device.
You must manually select Focusrite USB ASIO as the driver on your DAW’s Audio Setup* page.
Please refer to your DAW’s documentation (or Help les) if you are unsure where to select the ASIO
or Core Audio driver. The example below shows the correct conguration in the Ableton Live Lite
Preferences panel (Windows version shown).
* Typical name. Terminology may differ between DAWs.

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Once the Scarlett 4i4 is set as the preferred Audio Device* in your DAW, Inputs 1 to 4 and Outputs 1 to
4 will appear in your DAW’s Audio I/O preferences. Depending on your DAW, you may need to enable
certain inputs or outputs before use.
The two screenshots below show Inputs 1 & 2 and Outputs 1 & 2 enabled Input and Output Cong in
Ableton Live Lite’s Audio Preferences.
* Typical name. Terminology may differ between DAWs.
Loopback Inputs
Two additional inputs - “Inputs 5 & 6” – will be listed on the Input Cong page of your DAW’s I/O
Preferences. These are virtual “loopback” inputs within software, not additional physical inputs.
They can be used to record DAW tracks from sources within your computer, e.g., from a web browser.
Focusrite Control incudes a Loopback 1-2 mix tab, where you can choose which inputs to record.
Full details of how to use the loopback inputs can be found in the Focusrite Control User Guide.

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Examples of Usage
The Scarlett 4i4 is an excellent choice for several different recording and monitoring applications.
Some typical congurations are shown below.
Connecting a microphone or instrument
This setup shows a typical setup for recording with DAW software on your computer. You might record
guitar through Input 1 and vocals through Input 2 into your DAW, while monitoring the playback from
the DAW via headphones or speakers. Meanwhile, Inputs 3 and 4 (on the rear panel) are connected
to a line level source, this examples shows a Novation Peak connected to inputs 3 and 4.
The front panel inputs are “Combo” type, which accept an XLR male connector or a ¼” (6.35 mm)
jack plug. The full microphone preamplier gain range is only available to a mic connected via the
XLR contacts. If it is a “condenser” (or “capacitor”) microphone, you will need to turn on the 48 volt
phantom power for it to work by pressing the 48V button. Most modern microphones of other types,
e.g., dynamic or ribbon, will not be damaged by phantom power, but note some older mics may be; if
you have any doubt, please check the specication of your mic to ensure it is safe to use.

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The Scarlett 4i4 has no “Mic/line” switches – the Focusrite preamplier stages are automatically
congured for a microphone when you plug an XLR into an input, and for a line or instrument when
you connect a jack plug. Select INST from Focusrite Control (‘INST’ illuminates red) if you are
connecting musical instrument, e.g., a guitar in the example, via a TS guitar jack. Deselect INST if
you are connecting a line level source such as a keyboard, synthesiser or the balanced output of an
external audio mixer via a TRS jack. The Combo connectors accept both TRS and TS types of jack
plug for line level sources.
Input channels 1 and 2 of the Scarlett 4i4 each have a PAD function: when selected from Focusrite
Control (PAD illuminates green when active), the signal level fed to your DAW is reduced by 10 dB.
You will nd this useful if you need to feed the input from a source whose output level is particularly
“hot”, when you might notice clipping or the gain halo turning red, even at minimum gain.
Using Direct Monitoring
You will probably have heard the term “latency” used in connection with digital audio systems. In
the case of the simple DAW recording application described above, latency is the time it takes for
your input signals to pass through your computer and audio software, and back to you. While not an
issue for most simple recording situations, under some circumstances, latency can be a problem
for a performer who wishes to record while monitoring their input signals. This might be the case
if you need to increase the size of your DAW’s recording buffer, which could be necessary when you
record overdubs on a particularly large project using many DAW tracks, software instruments and FX
plug-ins. Common symptoms of a buffer setting too low could be glitching audio (clicks and pops),
or a particularly high CPU load within your DAW (most DAWs have CPU readouts). If you experience
this on a Mac, you can raise the buffer size from the DAW application itself but on a Windows PC you
will most likely need to change this from the ASIO Control Panel which can usually be accessed from
your DAW Setup Preferences*.
The Scarlett 4i4, in conjunction with Focusrite Control, allows “zero latency monitoring”, which
overcomes this problem. By using Focusrite Control to monitor your input signals, you will hear
yourself in real time along with the computer playback, even with high buffer sizes. The input signals
to the computer are not affected in any way by this setting. However, note that the effect of any plug-
ins instantiated in the DAW will not be heard whilst recording because by monitoring in this way you
are hearing the signal before it reaches the software. Also, remember to mute the channel you are
recording to in your DAW otherwise you will hear both the signal you are monitoring and the echo
effect of the signal coming back from the DAW.
* Typical name. Terminology may differ between DAWs.
Connecting Scarlett 4i4 to loudspeakers
Any of the Scarlett 4i4’s outputs may be used to connect monitoring speakers. All outputs are
electronically balanced, and available on the rear panel on ¼” (6.35 mm) 3-pole (TRS) jacks.
If LINE OUTPUTS 1 and 2are used for primary monitoring, LINE OUTPUTS 3 and 4are free to be
used for another purpose, such as connecting to an additional recording device or an additional pair
of monitors. However, please note only LINE OUTPUTS 1 and 2are affected in level by the large front
panel MONITOR volume control. Also please note Outputs 3 and 4 are also used to feed the front
panel headphone output.
The signals at LINE OUTPUTS 3 and 4 are at (full) xed level, and thus if you use these for monitoring,
you will have to control the volume either from Focusrite Control, or by adjusting the volume at an
external amplier.

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Active monitors (e.g., typical computer speakers) incorporate internal ampliers with a volume
control, and may be connected directly. Larger, passive loudspeakers will require a separate stereo
amplier; the outputs should be connected to the amplier’s inputs.
In the setup shown in the lower diagram, a small pair of active monitors connected to Outputs 3 and
4 could act as “neareld” monitors; their volume would either be adjusted locally on the speakers or
via Focusrite Control. The volume of the passive main monitors would be adjusted by the front panel
MONITOR control.
Typical consumer (hi-) ampliers and small powered monitors will have unbalanced inputs, either
on phono (RCA) sockets, or via a 3.5 mm 3-pole jack plug intended for direct connection to a computer.
In either case, use a suitable connecting cable with phono plugs (RCA jacks) at one end.
Professional power ampliers will generally have balanced inputs; we recommend using balanced
cables to connect these to the ¼” jack outputs of the Scarlett 4i4.
NOTE: You run the risk of creating an audio feedback loop if loudspeakers are active when you are
monitoring a microphone! We recommend you always turn off (or turn down) monitoring loudspeakers
while recording, and use headphones when overdubbing.

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Creating an effects loop
The Scarlett 4i4 allows the easy integration of external outboard processors or effects. A good
example is the inclusion of an outboard stereo compressor to a recording setup similar to that
outlined above.
Connect Line Outputs 3 and 4 to the compressor’s inputs, and the compressor’s outputs to Line
Inputs 3 and 4, as shown below. You can then route the channels from your DAW to outputs 3/4. In
Focusrite Control route Software Playback 3/4 to line outputs 3/4 and the signal will be sent to the
compressor. We have omitted the front panel connections in this example for clarity.
CH 1
IN OUT
CH 2
IN OUT
See previous example diagrams
for details of connectors
You can use Focusrite Control or your DAW software to adjust the levels to and from the external
processor if necessary or for creative effect.

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Connecting Scarlett 4i4 to a DJ mixer
The Scarlett 4i4 makes an excellent interface between a laptop running DJ software and the channels
of a DJ mixer. In this setup, Outputs 1 and 2 can be connected to Line Inputs 1 and 2 of an external DJ
mixer, and Outputs 3 and 4 to Line Inputs 3 and 4. Connecting in this way means all mixer facilities,
such as EQs and crossfading, are easily accessible. However, you must set the front panel Monitor
Level control to maximum, otherwise Outputs 1 and 2 will be at a lower level than Outputs 3 and 4.
Note that although the outputs of the Scarlett 4i4 are balanced, they can be connected to an unbalanced
input using a cable tted with a ¼” TS jack. Most DJ mixers will have unbalanced inputs using phono
(RCA) sockets, so suitable phono-to-TS jack cables will be needed to make the connection.

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HARDWARE FEATURES
Front Panel
4
2
1
197
5 6 45 6 11
3810
The Front Panel includes the input connectors for Mic, Line and Instrument signals, as well as the
input gain and monitoring controls.
1. Inputs 1 & 2 – “Combo” input sockets - connect microphones, instruments (e.g., guitar), or
line level signals here. Combo sockets accept both XLR and ¼” (6.35 mm) jacks. Microphones
connect using XLR plugs: instruments and line level signals should be connected via ¼” (6.35
mm) jack plugs of either TS or TRS type. The preamp gain is appropriate for microphones
when an XLR plug is inserted, and for higher level signals when a jack plug is inserted. Do not
connect anything other than a microphone - e.g., the output of a sound module or FX unit - via
an XLR plug, as the signal level will overload the preamp, resulting in distortion; , if phantom
power is enabled, you may damage your equipment.
2. GAIN 1 and GAIN 2 – adjust the preamp gain for signals at inputs 1 and 2 respectively. The gain
controls have tri-colour LED ‘rings’ to conrm signal level: green indicates an input level of
at least -24 dBFS (i.e., ‘signal present’), the ring turns amber at -6 dBFS to indicate the signal
is close to clipping, and red at 0 dBFS (digital clipping).
3. 48V – phantom power switch for mic inputs - enables 48 V phantom power at XLR contacts of
both Combo connectors.
4. INST – two red LEDs; illuminate when Instrument mode is selected for Inputs 1 or 2 from
Focusrite Control; gain is set to suit instrument signals. When INST is off, the ¼” jack input is
congured to accept a line level signal, e.g., from a keyboard, synth module or FX unit.
5. AIR – two yellow LEDs indicating AIR mode selection for Inputs 1 and 2. AIR mode, enabled in
Focusrite Control, modies the frequency response of the input stage to model the classic,
transformer-based Focusrite ISA microphone preamps.
6. PAD – two green LEDs; illuminate when PAD is selected from Focusrite Control for Inputs 1 or
2. PAD decreases the signal level going to your DAW by 10 dB; use when the input source has
a particularly high level.

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7. MONITOR – main monitor volume control, sets the level at rear panel Outputs 1 and 2 only.
8. Headphone level – adjusts the output level at the front panel stereo headphone output.
9. Headphone output - ¼” TRS output jack – connect your stereo headphones here.
10. USB LED – a green LED illuminates when the Scarlett is connected and recognised by
your computer.
11. MIDI LED – illuminates when MIDI data is received at the MIDI IN port.
Back Panel
16
17
15 121314
12. LINE INPUTS 3and 4– 2 x ¼” TRS jacks; these are balanced inputs for use with additional line
level sources e.g., from a keyboard, synth module or FX unit.
13. LINE OUTPUTS 1 and 2- 2 x ¼” (6.35 mm) TRS jack sockets, electronically balanced. The level
at these outputs is adjusted by the front panel MONITOR control, the maximum output level is
+10 dBu. Either ¼” TRS (balanced connection) or TS (unbalanced connection) jack plugs can
be used.
14. LINE OUTPUTS 3 and 4- 2 x ¼” (6.35 mm) TRS jack sockets, electronically balanced. The
level at these outputs may be adjusted from Focusrite Control; the maximum output level is
+10 dBu. Either ¼” TRS (balanced connection) or TS (unbalanced connection) jack plugs can
be used.
15. MIDI IN and MIDI OUT – standard 5-pin DIN sockets for connection of external MIDI equipment
such as keyboards or sound modules. The Scarlett 4i4 provides a convenient MIDI interface
with your DAW, making a computer MIDI card unnecessary.
16. USB 2.0 port – Type C connector; connect to your computer with cable supplied.
17. K (Kensington security lock) – secure your Scarlett 4i4 to a suitable structure if desired.

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CHANNEL LISTINGS
The tables below summarise how the Scarlett 4i4’s inputs and outputs will correspond to the input
and output channels in your chosen DAW.
Input 4i4 Hardware Inputs
44.1/48 kHz 88.2/96 kHz 176.4/192 kHz
Ch 1 Input 1 Input 1 Input 1
Ch 2 Input 2 Input 2 Input 2
Ch 3 Input 3 Input 3 Input 3
Ch 4 Input 4 Input 4 Input 4
Ch 5 Loopback 1 Loopback 1
Ch 6 Loopback 2 Loopback 2
Output Software playback (outputs)
44.1/48 kHz 88.2/96 kHz 176.4/192 kHz
Ch 1 Output 1 Output 1 Output 1
Ch 2 Output 2 Output 2 Output 2
Ch 3 Output 3 (Headphones L) Output 3 (Headphones L) Output 3 (Headphones L)
Ch 4 Output 4 (Headphones R) Output 4 (Headphones R) Output 4 (Headphones R)

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SPECIFICATIONS
Performance Specifications
All performance gures measured in accordance with the provisions of AES17, as applicable.
Supported sample rates 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz, 192 kHz
Custom Mixes 6 mono
Maximum custom mix inputs 8 mono
Microphone Inputs
Dynamic Range 111 dB (A-weighted)
Frequency Response 20 Hz to 20 kHz ±0.1 dB
THD+N <0.0012% (minimum gain, -1 dBFS input with 22 Hz/22 kHz
bandpass lter)
Noise EIN -128 dB (A-weighted)
Maximum Input Level +9 dBu (no PAD); +16 dBu (PAD selected);
measured at minimum gain
Gain Range 56 dB
Input impedance 3 kΩ
Line Inputs 1 and 2
Dynamic Range 110.5 dB (A-weighted)
Frequency Response 20 Hz to 20 kHz ±0.1 dB
THD+N <0.002% (minimum gain, -1 dBFS input with 22 Hz/22 kHz
bandpass lter)
Maximum Input Level +22 dBu (no PAD); +29.5 dBu (PAD selected);
measured at minimum gain
Gain Range 56 dB
Input impedance 60 kΩ
Instrument Inputs 1 and 2
Dynamic Range 110 dB (A-weighted)
Frequency Response 20 Hz to 20 kHz ±0.1 dB
THD+N <0.03% (minimum gain, -1 dBFS input with 22 Hz/22 kHz
bandpass lter)
Maximum Input Level +12.5 dBu (no PAD); +14 dBu (PAD selected); measured at
minimum gain
Gain Range 56 dB
Input impedance 1.5 MΩ