Focusrite Clarett 8Pre USB User manual

focusrite.com
Version 2
User Guide

2
TABLE OF CONTENTS
OVERVIEW..................................................................... 3
Introduction .................................................................3
Features ....................................................................4
Box Contents ................................................................5
System Requirements .........................................................5
Getting Started................................................................. 6
Software Installation ..........................................................6
Registering your Clarett USB ...................................................6
Hardware Features ...........................................................8
Front Panel ....................................................................8
Rear Panel ...................................................................10
Connecting your Clarett 8Pre USB ..............................................11
Computer audio setup ..........................................................11
Audio Setup in your DAW ........................................................11
Connecting Clarett 8Pre USB to loudspeakers ......................................12
Examples of Usage ..........................................................14
1. Recording a band ............................................................14
2. Using the optical connections ..................................................16
3. Using the Clarett 8Pre USB as a stand-alone mixer ................................17
4. Providing foldback while recording..............................................18
FOCUSRITE CONTROL - OVERVIEW...............................................19
CLARETT 8Pre USB TECHNICAL SPECIFICATIONS ..................................20
Performance Specications ...................................................20
Physical and Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
TROUBLESHOOTING ........................................................... 22
COPYRIGHT AND LEGAL NOTICES ................................................22

3
OVERVIEW
WARNING: Excessive sound pressure levels from earphones and headphones can cause
hearing loss.
WARNING: This equipment is only compatible with USB Type 2.0, 3.0 or 3.1 ports, or Thunderbolt™
3 ports. More information regarding the compatibility of computer serial ports can be found at:
support.focusrite.com/hc/articles/115002287829-USB-port-clarication-and-compatibility
Introduction
Thank you for purchasing this Clarett 8Pre USB, one of the family of Focusrite professional USB audio
interfaces incorporating high quality Clarett analogue pre-ampliers with the unique AIR function. In
conjunction with the Focusrite Control application, you now have a highly versatile and professional
solution for routing high quality audio to and from your computer recording system with extremely
low latency.
You can also use the Clarett 8Pre USB as a “stand-alone” interface on-stage, bringing the benets of
Focusrite’s high-quality analogue microphone preamps to your live performance.
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 you take the time to read
through the Guide, whether you’re new to computer recording or a more experienced user, so you
are fully aware of all the possibilities the Clarett 8Pre USB has to offer.
IMPORTANT: As well as this User Guide, you will need the Focusrite Control Software
Guide which can be downloaded from focusrite.com/downloads. This contains full details
of Focusrite Control, the software application that has been designed specically for use
with the Focusrite Clarett USB range of interfaces.
If either User Guide does not have the information you need, please go to support.focusrite.com,
where you can nd articles and tutorials beyond the scope of this user guide. A Getting Started video
tutorial is also available, at focusrite.com/get-started.

4
Features
The Clarett 8Pre USB hardware interface provides the means for connecting microphones, musical
instruments, line level audio signals and digital audio signals to a computer through the computer’s
USB port. 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”); similarly, the outputs from
the DAW can be congured to appear at the unit’s physical outputs.
Audio sources – mics, instruments, etc., can be recorded into your DAW and then played back
from there through ampliers and speakers, powered monitors, headphones, a mixer or any other
analogue or digital audio equipment you wish to use.
The Clarett 8Pre USB is also a MIDI interface, allowing your computer to connect to other MIDI
equipment in your studio.
An important feature of the Clarett 8Pre USB is the analogue preamplier design. In addition to
their class-leading dynamic range and ability to provide all the gain you’re ever likely to need,
the circuitry now includes an exciting new AIR function. Individually selectable on each channel,
AIR subtly modies the pre-amp’s frequency response to model the impedance and resonance
characteristics of Focusrite’s classic transformer-based ISA mic preamps. When recording with
good quality microphones, you will notice an enhanced clarity and denition in the important mid
frequency range, just where it is most needed for vocals and many acoustic instruments.
The accompanying software application, Focusrite Control, is designed to require a minimal amount
of user interaction, letting you easily congure the Clarett 8Pre USB with signal routings appropriate
for the most common recording tasks. For more complex situations, it provides extensive routing
and monitoring options, as well as the ability to control global hardware settings such as sample rate
and synchronisation. You can download Focusrite Control from focusrite.com/downloads.
iPad and iPhone users can additionally download Focusrite iOS Control from the App Store®. The
app communicates via WiFi with Focusrite Control running on your computer, and lets you adjust
your monitor mixes from your iOS device. For more information see:
support.focusrite.com/hc/articles/212028389-Focusrite-iOS-Control-Basic-setup

5
Box Contents
Along with your Clarett 8Pre USB you should have:
• External 12 V DC mains Power Supply Unit (PSU)
• USB-C to USB-A cable
• USB-C to USB-C cable
Focusrite Control is available at focusrite.com/downloads. On Windows, Focusrite Control will
also install the driver required. Mac users: Clarett 8Pre USB is class-compliant on Macs, therefore
no drivers are required.
As a Clarett owner, you are also entitled to a selection of third-party software. To nd out what’s
included, go to:
focusrite.com/usb-c-audio-interface/clarett-usb/clarett-8Pre USB-usb
System Requirements
IMPORTANT – Please visit the following link for up-to-date information on computer and
operating system compatibility for all Clarett products:
support.focusrite.com

6
GETTING STARTED
Software Installation
Focusrite Control and the driver software needed for the Clarett USB are available for download
from the Focusrite website: focusrite.com/downloads.
Click Clarett USB range on the Downloads page. This will take you to a page with all the downloads
which are available for the Clarett USB range.
To download the Focusrite Control version you need, click the appropriate Download button.
Note that the Windows driver is included within the Focusrite Control download. No additional
driver is needed for Macs.
Registering your Clarett USB
If you are having trouble with the steps below, please watch our video guide here:
focusrite.com/get-started
1. Go to focusrite.com/register
2. If you do not have already have a Focusrite/Novation account, select CREATE AN ACCOUNT and
follow the on-screen instructions.

7
3. If you do have an account, log in and select REGISTER A NEW PRODUCT:
4. Select your Clarett USB device from the Product drop-down list and enter your device’s Serial
Number at the bottom of the page. You can nd the serial number on the rear or underside of the
Clarett, and also on the gift box. Then click Set Serial Number.
5. Follow the rest of the on-screen instructions to nish registering your device.
6. When registration is complete, your Product will appear in your Account under the
My Hardware tab.
7. All your bundled software can be found under the My Software tab in your account.

8
Hardware Features
Front Panel
4
5
458 9 13
1414
11
1267 10 123
The front panel includes all the input gain and monitoring controls as well as two of the input
connectors for Mic, Line and Instrument signals.
1. INPUTS 1 & 2– Combo XLR input sockets - connect microphones, instruments (e.g., guitar), or
line level signals via XLR or ¼” jacks as appropriate. Either TRS (balanced) or TS (unbalanced)
jack plugs can be used for instruments or line level signals.
2. 48V – two switches enabling 48 V phantom power at the Combo connectors’ XLR contacts
for mic inputs 1-4 and 5-8 respectively. (Note that inputs 3 to 8 are on the rear panel.) Each
switch has a red LED to show when phantom power is enabled. Note that not all microphones
require phantom power. If you are unsure whether your microphone needs it to work, please
read the microphone documentation.
3. Gain 1to 8– eight rotary controls: adjust the input gain for the signals at Inputs 1 to 8.
4. INST – two red LEDs which illuminate when Instrument mode is selected for the jack
Inputs 1 or 2 from Focusrite Control software. When INST is selected, gain range and input
impedance are altered (relative to LINE), and the input is made unbalanced. This optimises
it for connecting instruments directly via a 2-pole (TS) jack plug. When INST is off, you can
connect line level signals. Line level signals may be connected either in balanced form via a
3-pole (TRS) jack or unbalanced, via a 2-pole (TS) jack.
5. AIR – eight yellow LEDs – one per input – which illuminate when the AIR function is selected
for the input from Focusrite Control. AIR modies the frequency response of the input stage
to model the classic, transformer-based Focusrite ISA mic preamps.
6. Meters – ten 6-segment LED bargraph meters indicating a) the signal levels of the eight
analogue input signals (meters 1to 8), and b) the signal levels at the MONITOR 1 and 2
outputs (meters Land R). The input meters show signal level after the input gain stage, and
thus their indication is affected by the gain controls. The output meters show signal level
before the monitor level control [10], which therefore does not affect their indication. The
LEDs illuminate at -42 (green, “signal present”), -18 and -12 dBFS (green), -6 and -3 dBFS
(yellow) and 0 dBFS (red). A level of 0 dBFS implies digital clipping, and should be avoided.
7. (USB active) – a green LED which illuminates when the unit has established communication
with the computer to which it is connected.
8. MIDI – a green LED which illuminates when MIDI data is being received at the rear panel
MIDI IN port.
9. (Locked) – a green LED which conrms clock synchronisation, either to the Clarett 8Pre
USB’s internal clock or to an external digital input.

9
10. MONITOR – main monitor output level control – this control will normally control the level
at the main monitor outputs on the rear panel, but can be congured in Focusrite Control to
adjust the level of multiple pairs of outputs.
11. DIM and MUTE – two switches controlling the Clarett 8Pre USB’s monitor outputs; DIM reduces
the output levels by 18 dB, while MUTE turns the outputs off. By default, these switches affect
the main monitor outputs 1 and 2, but may be congured in Focusrite Control to act on any
of the analogue outputs. The switches are internally illuminated (DIM: yellow, MUTE: red)
indicating that the function is selected.
12. (Headphones) 1and 2 – connect one or two pairs of stereo headphones at the two ¼” TRS
jack sockets below the controls. The headphone outputs always carry the signals currently
routed to analogue outputs 7/8 and 9/10 (as stereo pairs) in Focusrite Control.
13. POWER – AC power switch and LED.
14. Rack ears for mounting the Clarett 8Pre USB in a standard 19” equipment rack.

10
Rear Panel
58 7 4
1236
9
1. MIC/LINE INPUTS 3 to 8– Combo XLR input sockets - connect further microphones or line
level signals via XLR or ¼” jacks as appropriate. Either ¼” TRS (balanced) or TS (unbalanced)
jack plugs can be used for line level signals.
2. LINE OUTPUTS 3to 10 – eight balanced analogue line outputs on ¼” jack sockets; use TRS
jacks for a balanced connection or TS jacks for unbalanced. The signals routed to these
outputs are dened in Focusrite Control, and can typically be used for driving alternative
speakers (i.e., mideld, neareld, etc.), the additional speakers in a multichannel monitoring
system, or to send audio to outboard FX processors.
3. MONITOR 1 and 2– two balanced analogue line outputs on ¼” jack sockets; use TRS jacks
for a balanced connection or TS jacks for unbalanced. These are also Line Outputs 1 and 2,
and will generally be used for driving the main L and R speakers of your monitoring system.
However, the routing of signals to outputs may be customised in Focusrite Control.
4. OPTICAL IN and OUT – two TOSLINK connectors, each carrying eight channels of digital audio
in ADAT format at 44.1/48 kHz sample rate or four channels at 88.2/96 kHz. These are simply
additional inputs and outputs (respectively) to/from the Clarett 8Pre USB. The OPTICAL IN
connector may alternatively be congured to receive a two-channel S/PDIF signal from an
external source equipped with an optical S/PDIF output. You can select this option from
Focusrite Control.
5. WORD CLOCK OUTPUT – a BNC connector carrying the Clarett 8Pre USB’s word clock; this
may be used to synchronise other digital audio equipment.
6. – USB connector; connect the Clarett 8Pre USB to your computer with a USB cable.
7. MIDI IN and MIDI OUT – standard 5-pin DIN sockets to connect external MIDI equipment. You
can send/receive MIDI data between your computer and external MIDI devices.
8. SPDIF IN and OUT – two phono (RCA) sockets carrying two-channel digital audio signals in
or out of the Clarett 8Pre USB in S/PDIF format. Like all the other inputs and outputs, the
routing of S/PDIF signals may be customised in Focusrite Control.
9. AC mains – standard IEC receptacle. The Clarett 8Pre USB is tted with a “Universal” power
supply, and will run from any AC mains voltage from 100 to 240 V, at 50 or 60 Hz.

11
Connecting your Clarett 8Pre USB
The Clarett 8Pre USB should be connected to AC mains with the supplied AC power cable. Plug the
IEC connector into the rear panel IEC receptacle and turn the unit on with the front panel power
switch.
The Clarett 8Pre USB has a USB-C™ port (on the rear panel). Once the software installation is
complete, connect the Clarett 8Pre USB to your computer using a USB cable.
Computer audio setup
When you connect your Clarett 8Pre USB to your computer for the rst time, you will need to select
the Clarett 8Pre USB as the audio input/output device.
• Mac OS: selection is made in System Preferences >Sound: select the Focusrite device on
both the Input and Output pages.
• Windows: selection is made in Control Panel >Sound: right-click on the Focusrite device
and select Set as Default Device in both Recording and Playback tabs.
In case of difculty, full details of how to select the Clarett 8Pre USB as the audio device on all
operating systems can be found at focusrite.com/get-started/clarett-8Pre USB.
On all subsequent connections, your OS should automatically select the Clarett 8Pre USB as the
default audio device.
Audio Setup in your DAW
After installing the drivers and connecting the hardware, you can use the Clarett 8Pre USB with the
DAW of your choice.
Your DAW may not automatically select the Clarett 8Pre USB as its default I/O device. In this case,
you must manually select the driver on your DAW’s Audio Setup* page, and select Focusrite 8Pre
USB (Mac) or Focusrite USB ASIO (Windows). Please refer to your DAW’s documentation or Help
les if you are unsure where to select the Clarett 8Pre USB as your audio device.
* Typical name – page names may vary with DAW

12
Connecting Clarett 8Pre USB to loudspeakers
The 1/4” jack MONITOR outputs on the rear panel (Line Outputs 1 and 2) will normally be used to
drive monitoring speakers. Self-powered monitors (e.g., typical computer speakers) incorporate
internal ampliers, and may be connected directly. Passive loudspeakers will require a separate
stereo amplier; in this case, the rear panel outputs should be connected to the amplier’s inputs.
All the line output connectors are 3-pole (TRS) ¼” jack sockets, and are electronically balanced.
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 jack plugs at one end.
Professional power ampliers will generally have balanced inputs.
Connecting active speakers
Connecting passive speakers

13
When mixing, you can connect several pairs of additional speakers (mid-eld, near-eld, etc.) to
pairs of outputs and use Focusrite Control to route your mix to the different outputs as desired, to
check your mix on the different types of speaker.
IMPORTANT:
MONITOR 1 and 2outputs incorporate “anti-thump” circuitry that protects your speakers if
the Clarett 8Pre USB is turned on while the speakers (and amplier if used) are connected
and active.
LINE OUTPUTS 3 to 10 do not have this circuitry.
If you’re using additional speakers connected to these outputs, we recommend you power
your Clarett 8Pre USB on rst,
then turn on the speakers or power amplier.
But get into the habit of following the general rule in any case - it is
always good audio
practice to turn on a speaker system of any kind
after turning on the equipment feeding it.

14
Examples of Usage
The Clarett 8Pre USB is an excellent choice for numerous recording and monitoring applications.
Some typical congurations are shown below.
1. Recording a band
Bass GuitarGuitar
(Front Panel)
(Rear Panel)
Engineer’s Headphones
Stereo Keys
This setup illustrates a typical conguration for multitrack recording with DAW software on your
Mac.
A selection of sources – microphones, guitars and a keyboard – are shown connected to the Clarett
8Pre USB’s inputs. Note that only Inputs 1 and 2 can be congured to accept instruments directly, so
we have chosen to plug the guitars into Inputs 1 and 2. Ensure INST mode is selected for Inputs 1 and
2 from Focusrite Control, and the INST LEDs are illuminated.
The Clarett is connected to the Mac running DAW software via a USB cable. This carries all the input
and output signals between the DAW and the Clarett 8Pre USB. Once the audio setup is congured in
the DAW, each input source will be automatically routed to its own DAW track for recording.

15
A note about latency
You will probably have heard the term “latency” used in connection with digital audio systems. In the
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 recording situations, 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
your buffer size, which could be needed when you record overdubs on a large project using many
DAW tracks, software instruments and FX plug-ins.
Common symptoms of a buffer setting that is 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; on a Windows PC you will
need to change this from the ASIO ControlPanel which can usually be accessed from your DAW
Setup Preferences*.
The Clarett 8Pre USB, in conjunction with Focusrite Control, allows “low latency monitoring”,
which overcomes this problem. You can route your input signals directly to the Clarett 8Pre USB’s
headphone and line outputs. This enables the musicians to hear themselves with ultra-low latency
– i.e., effectively in “real time” – along with computer playback. The input signals to the computer
are not affected in any way by this setting. However, note that any effects being added to the live
instruments by software plug-ins will not be heard in the headphones in this case, although the FX
will still be present on the recording.
* Typical name – page names may vary with DAW

16
2. Using the optical connections
In addition to the eight analogue inputs, the Clarett 8Pre USB has an ADAT input port (OPTICAL IN)
which can provide an additional 8 audio inputs at 44.1/48 kHz sample rate, or four at 88.2/96 kHz.
Using a separate 8-channel microphone preamplier equipped with an ADAT output – such as the
Focusrite Clarett OctoPre – provides a simple and excellent method of expanding the Clarett 8Pre
USB’s input capability.
Computer
running DAW
and F
ocusrite Control
Inputs 1 & 2 on front panel
Optical ADAT connection (TOSLINK)
Optional Word Clock link
Inputs 1 & 2 on front panel
Up to 16 Mic/Line Sources
Clarett Octopre
8ch Mic Amp
The Clarett OctoPre’s OPTICAL OUT port is connected to the Clarett 8Pre USB’s OPTICAL IN port with
a single TOSLINK optical cable. Stable word clock synchronisation may be achieved by connecting
the Clarett 8Pre USB’s WORD CLOCK output to the Clarett OctoPre’s WORD CLOCK IN and setting
the Clarett OctoPre to use this as its sync source; alternatively, the Clarett 8Pre USB may be set (in
Focusrite Control) to synchronise via the ADAT format signal at the OPTICAL IN port.
NOTE: when interconnecting two digital devices by any method, always ensure that both are set to
use the same sample rate.
The additional inputs realised by use of the optical port may be routed using Focusrite Control in
exactly the same manner as the other inputs. The additional inputs can form part of any musician’s
headphone mix, as required.
If a suitable D-to-A converter with an ADAT input is available, the OPTICAL OUT port may be used
in the opposite manner; for example, additional outputs from the DAW may be converted into the
analogue domain to allow the use of an external hardware mixing console to mix down a large
number of DAW tracks.

17
3. Using the Clarett 8Pre USB as a stand-alone mixer
The Clarett 8Pre USB has the ability to store a mix conguration dened in Focusrite Control within
the hardware. This feature lets you congure it – for example, as an on-stage keyboard mixer – using
your computer, and then upload the conguration to the device itself. Then you can use the Clarett
8Pre USB as a simple, rack-mounting mixer as part of your keyboard rig to control the overall mix
of multiple keyboards.
To FOH Mixer
In the example illustrated, three stereo keyboards/synths are connected to the rear panel inputs
of the Clarett 8Pre USB; Outputs 3 and 4 go to the main PA system. The performer can adjust the
volume of the individual keyboards from the front panel; he/she can also independently adjust the
level they hear the mixed keyboards at through the speakers.

18
4. Providing foldback while recording
While recording, musicians will often prefer to hear themselves along with the other players, and
when overdubbing, the tracks that have already been recorded. A mix created for this purpose, which
the musician can hear on headphones while performing, is called foldback.
Focusrite Control lets you dene several different mixes, each of which may be either mono or stereo,
and which may be routed to any of the Clarett 8Pre USB’s outputs. This enables individual musicians
to have a foldback mix optimised to their own requirements. In this way, each foldback feed can
be made up from a different mix of a musician’s own input, the live contributions from the other
performers, and DAW tracks which have already been recorded. See the Focusrite Control Guide for
details of how to congure different mixes, and how to route them to the Clarett 8Pre USB’s various
outputs.
Each of the headphone outputs on the front panel initially provides a default mix: Headphone 1’s mix
is always the same stereo mix routed to Line Outputs 7 and 8, while Headphone 2’s mix is always
the same stereo mix routed to Line Outputs 9 and 10. You can adjust the content of both mixes in
Focusrite Control - that for Outputs 7/8 denes what is heard by Headphones 1, and that for Outputs
9/10 denes what is heard by Headphones 2.
Either or both of these may be used for foldback mixes; each output can drive a pair of headphones
directly. This is the easiest method, and has the advantage that the mixes are stereo. If you need to
drive additional pairs of headphones, you’ll need to include an external headphone amplier as part
of your set-up:
Headphone Distribution Amplifier
Always remember - when sourcing monitor mixes from input signals, ensure that the DAW channels
on which you are recording are muted, otherwise the musicians will hear themselves “twice”, with
one signal audibly delayed as an echo.

19
FOCUSRITE CONTROL - OVERVIEW
Focusrite Control is the software application used with the Clarett 8Pre USB, which can be
downloaded from focusrite.com/downloads. An iOS app allowing WiFi control of Focusrite Control
is also available, from the Apple App Store.
Focusrite Control allows you to create a custom monitor mix for each musician, and specify the
routing of all audio signals to the physical audio outputs. Sample rate and clock source selection are
also available from Focusrite Control.
Focusrite Control has its own dedicated User Guide, which has detailed operating
instructions for all aspects of the software. This may be downloaded from:
focusrite.com/downloads

20
CLARETT 8Pre USB TECHNICAL SPECIFICATIONS
Performance Specifications
Configuration
Inputs 18: analogue (8), S/PDIF (2), ADAT (8)
Outputs 8: analogue (4), S/PDIF (2), HP (2)
Mixer Fully assignable 26-in/10-out mixer
Custom Mixes 10 mono
Maximum custom mix inputs 18 mono
Digital Performance
Supported sample rates 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz & 192 kHz
Microphone Inputs
Frequency Response 20 Hz - 35 kHz +/-0.5 dB at minimum gain
Dynamic Range 118 dB
THD+N <0.001%
Noise EIN <–129 dBu (A-weighted)
Maximum input level +18 dBu at minimum gain
Gain Range 57 dB
Line Inputs
Frequency Response 20 Hz - 35 kHz +/-0.5 dB at minimum gain
Dynamic Range 118 dB
THD+N 0.001%
Maximum input level +26 dBu at minimum gain
Gain Range 57 dB
Instrument Inputs
Frequency Response 20 Hz - 35 kHz +/-0.5 dB at minimum gain
Dynamic Range 117 dB
THD+N 0.001%
Maximum input level +14 dBu at minimum gain
Gain Range 57 dB
Line & Monitor Outputs
Dynamic Range 118 dB
THD+N 0.0007%
Maximum Output Level (0 dBFS) +18 dBu at minimum gain, balanced line/TRS outputs
Headphone Outputs
Dynamic Range 115 dB (A-Weighted)
THD+N 0.0009%
Maximum Output Level +15 dBu