Universal Audio Apollo Twin MkII User manual

Apollo Twin MkII Hardware Manual
www.uaudio.com
Manual Version 170126

Apollo Twin MkII Hardware Manual Welcome2
A Letter from Bill Putnam Jr.
Thank you for deciding to make the Apollo Twin MkII High-Resolution Interface part
of your music making experience. We know that any new piece of gear requires an
investment of time and money — and our goal is to make your investment pay off.
The fact that we get to play a part in your creative process is what makes our efforts
meaningful, and we thank you for this.
In many ways, the Apollo family of audio interface products represent the best examples
of what Universal Audio has stood for over its long history; from UA’s original founding in
the 1950s by my father, through our current vision of delivering the best of both analog
and digital audio technologies.
Starting with its high-quality analog I/O, Apollo Twin MkII’s superior sonic performance
serves as its foundation. This is just the beginning however, as Apollo Twin is the only
desktop audio interface that allows you to run UAD plug-ins in real time. Want to monitor
yourself through a Neve® console channel strip while tracking bass through a classic
Fairchild or LA-2A compressor? Or how about tracking vocals through a Studer® tape
machine with some added Lexicon® reverb?* With our growing library of more than 90
UAD plug-ins, the choices are limitless.
At UA, we are dedicated to the idea that this powerful technology should ultimately serve
the creative process — not be a barrier. These are the very ideals my father embodied
as he invented audio equipment to solve problems in the studio. So as you begin to
incorporate Apollo Twin MkII into your creative process, we hope that the excitement and
pride that we’ve built into it comes through. We believe Apollo Twin MkII will earn its way
into your creative workflow by providing stunning fidelity, great ease-of-use, and rock-
solid reliability for years to come.
As always, please feel free to reach out to us via our website www.uaudio.com, and via
our social media channels. We look forward to hearing from you, and thank you once
again for choosing Universal Audio.
Sincerely,
Bill Putnam Jr.
*All trademarks are recognized as property of their respective owners. Individual UAD Powered Plug-Ins sold separately.

Apollo Twin MkII Hardware Manual Table Of Contents3
Table Of Contents
A Letter from Bill Putnam Jr. ................................................................. 2
Introduction ......................................................................................... 4
Welcome to Apollo! ............................................................................................ 4
Apollo Twin MkII Features .................................................................................. 7
Operational Overview.......................................................................................... 9
About Apollo Twin MkII Documentation.............................................................. 11
Additional Resources ....................................................................................... 12
Quick Start ........................................................................................ 13
Hardware Setup............................................................................................... 13
Software Setup................................................................................................ 14
Connect to Input Sources and Monitor System.................................................... 15
Setting Hardware I/O Levels.............................................................................. 16
Controls & Connectors......................................................................... 17
Controls Overview ............................................................................................ 17
Top Panel........................................................................................................ 20
Front Panel ..................................................................................................... 25
Side Panel ...................................................................................................... 25
Rear Panel ...................................................................................................... 26
Specifications .................................................................................... 28
Specification Tables ......................................................................................... 28
Hardware Block Diagram .................................................................................. 32
Troubleshooting .................................................................................. 33
Notices.............................................................................................. 34
Important Safety Information ............................................................................ 34
Warranty ......................................................................................................... 35
Maintenance ................................................................................................... 35
Repair Service ................................................................................................. 35
Technical Support............................................................................... 37
Universal Audio Knowledge Base....................................................................... 37
YouTube Support Channel................................................................................. 37
UAD Community Forums .................................................................................. 37
Contact UA Support ......................................................................................... 37
Tip: Click any section or page number
to jump directly to that page.

Apollo Twin MkII Hardware Manual Introduction4
Introduction
Welcome to Apollo!
Superior Desktop Audio Conversion with
Classic Analog Sound
With its class-leading resolution and Realtime
UAD Processing, Apollo Twin MkII sets a new
standard for desktop music production. This 2x6
Thunderbolt interface for Mac and Windows allows
you to record with near-zero latency through the
full range of UAD Powered Plug-Ins — ingeniously
merging classic analog tones with cutting-edge
features.
Now You Can:
• Record with world-class Apollo A/D and D/A
conversion — as heard on hundreds of hit
records
• Cascade up to 4 Apollo interfaces and 6
UAD-2 devices over Thunderbolt, adding
DSP and I/O as your studio grows
• Mix with UAD plug-ins like the included
Teletronix® LA-2A, 1176, and Fairchild®
compressors, Pultec® EQs, and 610-B
Preamp
• Track with near-zero latency through preamp
emulations from Neve®, API®, Manley®
and more using Unison™ technology*
Unison Technology: The Genuine Sound of Neve, API & Manley Preamps
Apollo Twin MkII features two Unison-enabled mic preamps, letting you track through
exacting mic preamp emulations from Neve, API, Manley, and Universal Audio. An Apollo
exclusive, Unison technology nails the tone of these sought-after tube and solid state mic
pres — including their input impedance, gain stage “sweet spots,” and the component-
level circuit behaviors of the original hardware.
The secret to Unison is its hardware-software integration between Apollo Twin MkII’s mic
preamps and its onboard UAD-2 SOLO, DUO, or QUAD Core DSP Acceleration. Simply
place a Unison preamp plug-in on your mic input, and tap into the classic sounds of the
world’s most recorded mic preamps.
MIC/LINE 1 MIC/LINE 2
3 L
4 R
LINE OUT MONITOR
OPTICAL IN
OFF ON 12VDC
POWER
MONITOR

Apollo Twin MkII Hardware Manual Introduction5
A Full Suite of Classic Analog Processing Onboard
Right out of the box, Apollo Twin MkII provides a suite of incredible analog emulation
plug-ins including the world’s only authentic Teletronix LA-2A, 1176LN, and Fairchild
compressors, the legendary Pultec EQs, and the Unison-enabled UA 610-B Tube
Preamp. Developed by UA’s world-renowned team of algorithm engineers, these Realtime
Analog Classic plug-ins set the standard by which all other hardware emulation plug-ins
are judged.
From the tube warmth of the Pultec EQ on guitars, to the gentle limiting of the LA-2A on
vocals, or the pump of a genuine Fairchild 670 compressor on drums, your recordings
will take a giant leap forward in rich, sonically complex analog sound.
Access the World of UAD Powered Plug-Ins
Beyond the included plug-ins, Apollo Twin MkII lets you tap into the full library award-
winning UAD Powered Plug-Ins — including vintage EQs, Compressors, Reverbs, Tape
Machines and more — at near-zero latency, regardless of your audio software’s buffer
size and without taxing your computer’s CPU.
With exclusive emulations from Neve, Studer, Manley, API, Ampex, Lexicon, Fender,
and more,* it’s like having an endless analog studio, right on your desktop. And unlike
competing interfaces, these DSP-powered plug-ins are also available in your DAW for
mixing.
Next-Generation A/D and D/A Conversion
Of course, the heart of any audio interface is the quality of its conversion. With the
highest dynamic range and lowest noise of any desktop interface, Apollo Twin MkII gives
you stellar 24-bit/192 kHz sound and breathtaking clarity. Its premium Unison mic
preamps, input stage, and audio conversion are identical to the famed Apollo series,
translating into rich three-dimensional recordings with exceptional depth and punch.
Apollo: The Choice of New-School Professionals
Apollo is the confirmed choice of hit-making professionals, used to record records
by Kendrick Lamar (To Pimp A Butterfly), Coldplay (A Head Full of Dreams), Dr. Dre
(Compton), Brad Paisley (Wheelhouse), and many more. The Apollo range of interfaces
has earned numerous industry awards from Sound on Sound, Future Music and
Electronic Musician — as well as the prestigious 2016 TEC Award for computer audio
hardware.
Now with Vintage Amps and Stompboxes
Apollo Twin MkII also includes Unison technology on its front panel instrument input,
giving you dead-on emulations of guitar and bass amps like the Fender ‘55 Tweed
Deluxe, Marshall Plexi Super Lead 1959, and Ampeg B-15N Bass Amplifier, as well as
iconic stompboxes like the Ibanez Tube Screamer.
*All trademarks are recognized as property of their respective owners. Individual UAD Powered Plug-Ins sold separately.

Apollo Twin MkII Hardware Manual Introduction6
Build a Networked Studio
Apollo Twin MkII offers up to 10 x 6 simultaneous input/output channels, with two built-
in Thunderbolt ports. Thanks to Apollo Expanded software, users of any Thunderbolt-
equipped Apollo Twin, Apollo Twin MkII, Apollo 8, Apollo 8p, and Apollo 16 audio
interfaces can combine up to four Apollos and six total UAD-2 devices — adding I/O
and DSP as your studio grows. Apollo Twin MkII makes the perfect intelligent desktop
controller for a full Apollo system.
A Sleek, Low-latency App
With Apollo Twin MkII’s Console 2 application — a complete re-imagining of Apollo’s
original Console software — you can take advantage of over 25 new user-requested
features such as Channel Strip presets, Drag & Drop functionality, dynamically resizable
windows, and more.

Apollo Twin MkII Hardware Manual Introduction7
Apollo Twin MkII Features
Key Features
• Best in class audio quality with improved 24-bit/192 kHz conversion
• Realtime UAD Processing — track through vintage compressors, EQs, tape machines,
and guitar amp/pedal plug-ins with near-zero latency
• 2 premium mic/line preamps; 2 line outs; front-panel Hi-Z instrument input and
headphone output
• Unison™ technology for stunning models of classic mic preamps and guitar amps
• Built-in talkback microphone for communication and recording
• Monitor remote functions can replace dedicated monitor controllers
• UAD-2 SOLO, DUO, or QUAD DSP processing onboard
• Thunderbolt connection for blazing-fast PCIe speed on modern computers
• Uncompromising analog design, superior components, and premium build quality
throughout
• Digitally controlled analog monitor outputs for full resolution at all listening levels
• Cascade up to four Thunderbolt-equipped Apollos and six total UAD-2 devices — adding
I/O and DSP as needed
All Features
Audio Interface
• Sample rates up to 192 kHz at 24-bit word length (96 kHz max on S/PDIF inputs)
• Up to 10 x 6 simultaneous input/output channels
• Two channels of analog-to-digital conversion via:
• Two balanced mic/line inputs
• One Hi-Z instrument input
• Six channels of digital-to-analog conversion via:
• Digitally-controlled stereo monitor outputs
• Stereo headphone outputs
• Line outputs 3-4
• Up to eight channels of digital inputs via:
• Eight channels ADAT optical with S/MUX for high sample rates, or
• Two channels S/PDIF optical with sample rate conversion
Microphone Preamplifiers
• Two high-resolution, ultra-transparent, digitally-controlled analog mic preamps
• Front panel and software control of all preamp parameters
• Low cut filter, 48V phantom power, 20 dB pad, polarity inversion, and stereo linking

Apollo Twin MkII Hardware Manual Introduction8
Monitoring
• Digitally-controlled analog monitor outputs maintains highest fidelity
• Independently-addressable stereo headphone outputs
• Independently-addressable line outputs 3-4 can be used for additional cue mix
• Front panel control of level, mute, dim, mono, alternate speakers, and talkback
• Built-in talkback microphone for communication and recording
UAD-2 Inside
• One (SOLO), two (DUO), or four (QUAD) SHARC DSP processors
• Realtime UAD Processing on all analog and digital inputs
• Same features and functionality as other UAD-2 devices when used with a DAW
• Complete UAD Powered Plug-Ins library is available online
Software
Console application:
• Enables tracking and/or monitoring with Realtime UAD Processing
• Remote control of Apollo Twin MkII features and functionality
• Virtual I/O for routing DAW tracks through Console
• Two independent stereo Auxiliary busses
Console Recall plug-in:
• Saves Apollo Twin MkII configurations inside DAW sessions for easy recall
• Facilitates control of Apollo Twin MkII monitoring features from within the DAW
• VST, RTAS, AAX 64, and Audio Units plug-in formats
UAD Meter & Control Panel application:
• Configures global UAD settings and monitors system usage
Other
• Attractive and durable desktop form factor
• Locking power supply prevents accidental disconnection
• Easy firmware updates
• One year warranty includes parts and labor
Package Contents
• Apollo Twin MkII unit
• Power supply with (4) AC connectors
(Changeable AC connectors for USA, Europe, UK, Australia, and China)
• Getting Started URL card

Apollo Twin MkII Hardware Manual Introduction9
Operational Overview
Audio Interface
First and foremost, Apollo Twin MkII is a premium 2 x 6 Thunderbolt audio interface with
world-class 24-bit/192 kHz audio conversion. Apollo Twin MkII connects to the outputs and
inputs of other audio gear, and performs analog-to-digital (A/D) and digital-to-analog (D/A) audio
conversions on the gear’s signals. The digital audio signals are routed into and out of the host
computer via the high-speed PCIe protocol, which is carried on a single Thunderbolt cable.
Apollo Twin MkII leverages Universal Audio’s expertise in DSP acceleration, UAD Powered
Plug-Ins, and analog hardware design by integrating the latest cutting edge technologies in
high-performance A/D-D/A conversion, DSP signal reconstruction, and connectivity. Apollo Twin
MkII acts as an audio interface with integrated DSP effects for tracking and monitoring, a fully
integrated UAD-2 DSP accelerator for mixing and mastering, as well as a complete monitoring
controller.
About Realtime UAD Processing
Apollo Twin MkII has the ability to run UAD Powered Plug-Ins in realtime. Apollo Twin MkII’s
groundbreaking DSP + FPGA technology enable UAD plug-ins to run with latencies in the sub-
2ms range, and multiple plug-ins can be stacked in series without additional latency.
Realtime UAD Processing facilitates the ultimate sonic experience while monitoring and/or
tracking.
Note: Apollo Twin MkII, like other UAD-2 devices, can only load UAD Powered Plug-Ins,
which are specifically designed to run on UAD-2 DSP accelerators. Native (host-based)
plug-ins cannot run on the UAD-2 DSP.
Console Software
The Console software application runs on the host computer and is used to control Apollo Twin
MkII mixing and monitoring with Realtime UAD Processing, access the audio interface I/O
settings, and more. Console’s analog-style workflow is designed to provide quick access to the
most commonly needed features in a familiar, easy-to-use mixer interface.
Realtime UAD Processing is a special function that is available only within Console. All
of Apollo Twin MkII’s analog and digital inputs can perform Realtime UAD Processing
simultaneously, and Console inputs with (or without) Realtime UAD Processing can be routed
into the DAW for recording.
Console controls Apollo Twin MkII’s digital mixer so you can monitor Apollo Twin MkII’s inputs
(with or without Realtime UAD Processing) without using any other audio software such as a
DAW.
Console is integral to unleashing the power of Apollo Twin MkII. For complete details about how
to use Console and Realtime UAD Processing, refer to the Apollo Software Manual.

Apollo Twin MkII Hardware Manual Introduction10
UAD Powered Plug-Ins in a DAW
Apollo Twin MkII and UAD plug-ins can also be used within a DAW without the use of
Console. UAD plug-ins loaded within the DAW operate like other (non-UAD) plug-ins,
except the processing occurs on the Apollo Twin MkII DSP instead of the host computer’s
processor. In this scenario, UAD plug-ins are subject to the latencies incurred by I/O
buffering.
For details about using UAD Powered Plug-Ins in a DAW, see the UAD System Manual.
Standalone Use
Although the Console application is required to utilize all Apollo Twin MkII features,
the hardware unit can be used as a digital mixer with limited functionality without a
Thunderbolt connection to a host computer.
All currently active I/O assignments, signal routings, and monitor settings are saved to
internal firmware when Apollo Twin MkII is powered down and persist when power is re-
applied. Therefore the last-used settings are always available even when a host computer
is not connected.
Note that UAD plug-in instantiations are not retained on power down, because the plug-
in files reside on the host computer. However, if UAD plug-ins are active when Apollo
Twin MkII’s connection to the host system is lost (if the Thunderbolt cable is unplugged),
the current UAD plug-in configurations remain active for processing until Apollo Twin
MkII is powered down.
Note: Standalone use is unavailable when cascading multiple Apollo units.

Apollo Twin MkII Hardware Manual Introduction11
About Apollo Twin MkII Documentation
Documentation for Apollo Twin MkII and UAD Powered Plug-Ins are separated by areas
of functionality, as described below. The user manuals are placed on the system drive
during software installation, and they can be downloaded at www.uaudio.com.
Apollo Manual Files
Note: All manual files are in PDF format. PDF files require a free PDF reader
application such as Adobe Acrobat Reader or Preview (included with macOS).
Apollo Hardware Manuals
Each Apollo model has a unique hardware manual. The Apollo hardware manuals contain
complete hardware-related details about one specific Apollo model. Included are detailed
descriptions of all hardware features, controls, connectors, and specifications.
Note: Each hardware manual contains the unique Apollo model in the file name.
Apollo Software Manual
The Apollo Software Manual is the companion guide to the Apollo hardware manuals.
It contains detailed information about how to configure and control all Apollo software
features using the Console application, Console Settings window, and Console Recall
plug-in. Refer to the Apollo Software Manual to learn how to operate the software tools
and integrate Apollo’s functionality into the DAW environment.
Note: Each Apollo connection type (Thunderbolt, FireWire, USB) has a unique
software manual.
UAD System Manual
The UAD System Manual is the complete operation manual for Apollo’s UAD-2
functionality and applies to the entire UAD-2 product family. It contains detailed
information about installing and configuring UAD devices, the UAD Meter & Control
Panel application, buying optional plug-ins at the UA online store, and more. It includes
everything about UAD except Apollo-specific information and individual UAD plug-in
descriptions.
UAD Plug-Ins Manual
The features and functionality of all individual UAD Powered Plug-Ins is detailed in the
UAD Plug-Ins Manual. Refer to this document to learn about the operation, controls, and
user interface of each UAD plug-in that is developed by Universal Audio.
Direct Developer Plug-In Manuals
UAD Powered Plug-Ins includes plug-in titles created by our Direct Developer partners.
Documentation for these 3rd-party plug-ins are separate files written and provided by the
plug-in developers. The file names for these plug-in manuals are the same as the plug-in
titles.

Apollo Twin MkII Hardware Manual Introduction12
Accessing Installed Documentation
Any of these methods can be used to access installed documentation:
• Choose Documentation from the Help menu within the Console application
• Click the Product Manuals button in the Help panel within the UAD Meter &
Control Panel application
• Manuals are also available online at help.uaudio.com
Host DAW Documentation
Each host DAW software application has its own particular methods for configuring and
using audio interfaces and plug-ins. Refer to the host DAW’s documentation for specific
instructions about using audio interface and plug-in features within the DAW.
Additional Resources
For additional resources, or if you need to contact Universal Audio for assistance, see the
Technical Support page.

Apollo Twin MkII Hardware Manual Quick Start13
Quick Start
Apollo Twin MkII hardware and software installation and setup consists of these steps:
1. Hardware Setup: Connect and power the Apollo Twin MkII hardware
2. Software Setup: Download and install the Apollo Twin MkII software
3. Connect to Input Sources and Monitor System
4. Setting Hardware I/O Levels: Learn how to adjust input and output levels
Hardware Setup
Select a Suitable Location
• Locate Apollo Twin MkII on a flat surface so its feet will maintain airflow beneath the
unit.
• The location should be sturdy enough to securely hold its weight and withstand
the pressure of operating the top panel controls.
• Leave enough room behind the unit for connected cabling.
• Do not block the cooling vents on the bottom or sides of the unit.
Connect to Computer and Power
Caution: Before powering Apollo Twin MkII on or off, lower the volume of the
monitor speakers (if connected) and remove headphones from your ears.
1. Connect one Thunderbolt cable (not included) between Apollo Twin MkII and the
host computer.
2. Connect the included power supply to an AC outlet (Apollo Twin MkII cannot be
bus powered).
3. Connect the locking power supply to the rear panel of Apollo. Align the two tabs
on the power cable's connector to the notches on the input, then rotate the barrel
to prevent accidental disconnection.
Important: After ensuring the locking barrel tabs are aligned with the chassis slots
and the barrel is fully inserted, rotate the barrel to secure the connector.
4. Apply power to Apollo Twin MkII using the rear panel's power switch. Apollo Twin
MkII is now ready for Software Setup.
12VDC
1. Align Tabs
2. Rotate to Lock

Apollo Twin MkII Hardware Manual Quick Start14
Software Setup
Note: Items on this page are detailed in the Apollo Software Manual. See About Apollo
Twin Documentation for related information.
System Requirements
All system requirements must be met for Apollo Twin MkII to operate properly. Before
proceeding with installation, see the system requirements in the Apollo Software Manual.
Software Installation
The software must be installed to use the hardware and UAD plug-ins. The UAD Powered Plug-
Ins software installer contains the Apollo Twin MkII software and drivers.
Important: For optimum results, connect and power on Apollo Twin MkII before installing
the software.
To obtain the latest UAD Powered Plug-Ins software installer, visit:
• www.uaudio.com/downloads
Registration and Authorization
Apollo Twin MkII must be registered and authorized to unlock UAD plug-ins that are bundled
with the product. Registration and authorization via a web browser is triggered automatically by
the UAD software the first time the device is recognized.
System Configuration
Complete details about setting up the Apollo Twin MkII system, including how to integrate with
a DAW and related information, are included in the Apollo Software Manual.
Console Application
The included Console application is the software interface for the Apollo Twin MkII hardware.
Console controls Apollo Twin MkII and its digital mixing, monitoring, and Realtime UAD
Processing features. Console is also used to configure Apollo Twin MkII’s I/O settings such as
sample rate, clock source, and reference levels.
For complete details about how to operate Console, refer to the Apollo Software Manual.
Apollo Expanded
When more I/O and/or DSP is needed, up to four Apollo interfaces can be cascaded together via
Thunderbolt in a multiple-unit configuration. For complete details about multi-unit cascading,
refer to the Apollo Thunderbolt Software Manual.
UA Support Videos
Many informational videos are available online to help you get started with Apollo Twin MkII:
• help.uaudio.com

Apollo Twin MkII Hardware Manual Quick Start15
Connect to Input Sources and Monitor System
One typical Apollo Twin MkII setup is illustrated below. For complete details about all of Apollo
Twin MkII's connectors and controls, see Controls & Connectors.
Typical Apollo Twin MkII setup connections
MIC/LINE 1 MIC/LINE 2
3 L
4 R
LINE OUT MONITOR
OPTICAL IN
OFF ON 12VDC
POWER
Speaker
System
Instrument Headphones
Microphone

Apollo Twin MkII Hardware Manual Quick Start16
Setting Hardware I/O Levels
This section explains how to set input gain levels for the hardware inputs (mic, line, and Hi-Z)
and adjust volume levels for the hardware outputs (monitors and headphones).
Refer to the Top Panel illustration for the control names and numbers mentioned below.
Important: Before proceeding, lower the volume of the monitor speakers and remove
headphones from your ears.
Set Input Gains
1. Select the input channel to be adjusted by pressing the Preamp button (7) until the
Channel Selection Indicator (3) displays the channel (CH1 or CH2).
2. Select the input type (mic or line) by pressing the Input Select button (13-a) until the
Input Type indicator (5) displays the desired input jack* (see note below).
3. Adjust the channel's gain by increasing the Level knob (1) until the input meter for
the channel (4) approaches maximum, but does not reach the red clip LED when the
input signal is present. If the level is too high to avoid clipping (when the red “C” LED
illuminates), enable the pad (13-d).
4. To set the input gain for the other input channel, repeat steps 1 – 3.
Adjust Output Volumes
1. Select the output volume to be adjusted (monitor or headphone) by pressing the Monitor
button (11) until the Monitor Selected (8) or Headphone Selected (10) indicator is lit.
2. Set the volume level by carefully increasing the Level knob (1) until the desired volume
is reached (you may need to adjust the volume of the speaker system).
3. To set the other output volume (monitor or headphone), repeat steps 1 – 2.
Mute (and Unmute) Monitor Outputs
1. Select the Monitor outputs by pressing the Monitor button (11) until the Monitor
Selected (8) indicator is lit.
2. Press the MUTE button (13-l) to mute the monitor outputs. The Monitor Selected
Indicator (8) is red when the monitors are muted. When in MONITOR Mode, the Volume
Level Indicator LEDs (2) are also red.
3. To toggle the monitor mute state, press the MUTE button (13-l) whenever Monitor (8) is
selected.
Notes:
• *The Hi-Z input is automatically selected, overriding the channel 1 Mic and Line inputs,
when a ¼” mono TS (tip-sleeve) plug is connected to the Hi-Z Instrument jack (14) on
the front panel.
• To control both channels simultaneously when a stereo source is connected, press the
Link button (13-f) when an input is selected (3).
• Line outputs 3 & 4 are accessed and controlled via software only (Console or DAW).
• Refer to the Apollo Software Manual to learn how to configure the audio interface set-
tings, use the Console application and Realtime UAD Processing, and more.

Apollo Twin MkII Hardware Manual Controls & Connectors17
Controls & Connectors
Complete details about the Apollo Twin MkII hardware controls and all connector jacks
on the front and rear panels are provided in this chapter.
Note: To learn how to set input gain levels (mic, line, and Hi-Z) and output
volumes (monitors and headphones), see Setting Hardware I/O Levels in the Quick
Start chapter.
Controls Overview
Some Apollo Twin MkII controls have multiple functions. The function of each control
depends on the current operating mode and the current settings within that mode. To
control a particular function, the control must be activated.
Operating Modes
Apollo Twin MkII’s top panel has two operating modes: Preamp and Monitor. The
function and availability of the top panel controls vary depending on the active operating
mode. The active mode is selected with the PREAMP and MONITOR buttons. Press the
button to activate the mode. Each mode is explained in greater detail below.
Note: All top panel functions can be operated concurrently (without switching
modes) from within the companion Console software application. See the Apollo
Software Manual for details.
PREAMP Mode
When Apollo Twin MkII is in Preamp mode, all top panel controls are related
to the input functions only. To adjust any input function, press the PREAMP
button to enter preamp mode and activate the input channel controls.
Note: Monitor and headphone functions cannot be performed in preamp
mode.
Preamp Channels
Apollo Twin MkII has two independent analog input channels. Each input channel has a
preamplifier. Both input channels can be independently controlled and used at the same
time for A/D conversion.
Preamp Controls
Apollo Twin MkII has one set of input channel preamp controls. The input channel
controls adjust all preamp functions for the currently selected input channel.
MONITOR

Apollo Twin MkII Hardware Manual Controls & Connectors18
Selected Channel
The currently selected input channel is shown by the CH1 and CH2
indicators at the upper left of the main display panel, above the input
meters. The top panel controls only adjust the functions for the currently
selected channel.
Changing Channels
When in Preamp mode, press the PREAMP button to change the selected channel so its
controls can be adjusted. Press PREAMP again to switch back to the other channel.
Input Source
The Mic, Line, or Hi-Z input is routed into the channel’s preamplifier. The
input source is shown by the indicators below the input meters.
The Mic or Line input source is selected by the pressing the INPUT button
when the channel is selected. The Hi-Z input (available on channel 1 only)
is selected automatically when and instrument cable is plugged into the
Hi-Z input on the front panel.
Note: Only one input type at a time (Mic, Line, or Hi-Z) can be used as a
channel’s input source.
Preamp Options
Each input channel has a set of preamp
options. The preamp options for the
currently selected input channel are
activated using the row of six buttons
at the bottom of the top panel when in
PREAMP mode.
The current state of the preamp options are indicated in the upper row of the options
display panel above the option buttons. Available options are dim when inactive, bright
when enabled, and unlit when unavailable.
Note: Not all preamp options are available with all input types. For specific
details, see the Top Panel Controls section later in this chapter.
MONITOR
MONITOR
MONITOR

Apollo Twin MkII Hardware Manual Controls & Connectors19
MONITOR Mode
When Apollo Twin MkII is in Monitor mode, all top panel controls are related
to output functions only. To adjust any output function, press the MONITOR
button to enter Monitor mode and activate the monitor controls.
Note: Input functions cannot be performed in Monitor mode.
Important: Apollo Twin MkII must be in Monitor mode to change the volume of the
monitor and headphone outputs.
Stereo Outputs
Apollo Twin MkII has two stereo outputs that can be controlled with the top panel
hardware: Monitor and Headphone. The stereo outputs are independently controlled.
Note: Line outputs 3 and 4 are controlled with software only.
Output Controls
The Level knob is used to set the volume level for each stereo output independently. The
Level knob adjusts the volume for the currently selected stereo output. After switching
the selected output with the MONITOR button, the other output volume can be adjusted.
Output Selection
The currently selected stereo output is shown by the MONITOR and
HEADPHONE indicators at the right of the main display, above and below
the output meters.
When in Monitor mode, press the MONITOR button to change the selected
output. Press again to switch to the other output. The Level knob adjusts
volume for the currently selected output.
Monitor Options
Apollo Twin MkII has monitor options
that perform the functions of dedicated
monitor controller. The monitor options
are controlled using the row of six buttons
at the bottom of the top panel when in
MONITOR mode.
The current state of the monitor options are indicated in the lower row of the options
display panel above the option buttons. Available options are dim when inactive, bright
when enabled, and unlit when unavailable.
Note: Not all monitor options are always available. For specific details, see the Top
Panel Controls section later in this chapter.
MONITOR
MONITOR
MONITOR

Apollo Twin MkII Hardware Manual Controls & Connectors20
Top Panel
Refer to the illustration below for control descriptions in this section.
Top panel elements
(1) Level Knob
The Level knob controls multiple functions. The knob’s current function is selected with
the PREAMP (7) and MONITOR (11) buttons.
When in PREAMP Mode, rotate clockwise to increase the amount of preamp gain for the
currently selected channel. When in Operating Modes, rotate clockwise to increase the
monitor output level or headphone output level, depending on the output selected with
the MONITOR (11) button.
Unison Integration
The Level knob can also be used to control Unison-enabled UAD preamp and
guitar amp plug-ins. See the Apollo Software Manual for complete Unison
details.
(2) Preamp Gain & Volume Level Indicator LEDs
The LEDs around the Level knob indicate the relative level of the selected function
(input preamp gain or monitor/headphone volume).
Note: The indicator LEDs are RED when MONITOR (11) is selected and MUTE
(13-l) is enabled.
MONITOR
1
2
7
6
11
13
3
4
5
8
9
10
12