Universal Audio Apollo x4 User Manual (English)

Questions and Answers:

C
Christopher ChapmanJul 27, 2025
How to fix audio glitches during DAW playback with Universal Audio Apollo x4?
- R
  Robert BarnesJul 27, 2025
  If you're experiencing audio glitches or dropouts during DAW playback with your Universal Audio Recording Equipment, try increasing the I/O Hardware Buffer. For Mac, adjust this in your DAW settings; for Windows, find it in Console settings. Additionally, if you're syncing to an external digital clock via optical input, check your clocking setups. Ensure the optical cable connections are secure, the sample rates match, and all devices are synchronized to one master clock device.
M
Matthew ThompsonJul 31, 2025
Why won't my Universal Audio Apollo x4 power on?
- B
  barbara34Aug 1, 2025
  If your Universal Audio Recording Equipment unit won't power on, first, ensure the power supply connector is fully inserted and twisted to lock. Next, check that the power switch is in the “ON” position. Finally, confirm AC power is available at the wall socket by plugging in a different device.
M
Mrs. Andrea BennettAug 5, 2025
What to do if I hear echo with Universal Audio Apollo x4 Recording Equipment?
- M
  Matthew ClarkAug 5, 2025
  If you're getting undesirable echo or phasing with your Universal Audio Recording Equipment, ensure that input monitoring is not enabled in both Console and your DAW. If monitoring via Console, disable software input monitoring. Alternatively, if using software input monitoring via DAW, mute all Console inputs.
C
Catherine LoweAug 8, 2025
Why can’t I hear mic inputs on my Universal Audio Apollo x4 Recording Equipment?
- E
  Erik CrossAug 8, 2025
  If you can't hear mic inputs on your Universal Audio Recording Equipment, confirm that +48V phantom power is enabled if required by the microphone.
S
Sarah PollardAug 12, 2025
How to adjust digital input levels on Universal Audio Apollo x4?
- A
  Aaron HernandezAug 13, 2025
  Signal levels for digital inputs on Universal Audio Recording Equipment are adjusted at the device connected to those inputs. UAD plug-ins can be used to add signal gain if desired.
J
Joshua GomezAug 17, 2025
Why is there static from Universal Audio Apollo x4 when nothing is plugged in?
- B
  Bridget AlexanderAug 17, 2025
  If you hear static or white noise when nothing is plugged into your Universal Audio Recording Equipment, try muting or lowering the preamp gain to minimum on unused preamp channels, as mic preamps can emit noise even when nothing is plugged in. Also, some UAD plug-ins model the noise characteristics of the original equipment; you can defeat the noise model in the UAD plug-in interface or mute the channel containing the plug-in to temporarily mute the noise.
Y
ytaylorAug 22, 2025
What to do if Apollo x4 Universal Audio Recording Equipment is behaving unexpectedly?
- J
  jjonesAug 22, 2025
  If your Apollo x4 Universal Audio Recording Equipment is behaving unexpectedly, perform a hardware reset. To do this: 1. Power off Apollo x4. 2. Press and hold the PREAMP, FILTER, and POLARITY buttons. 3. Power on Apollo x4 while continuing to hold all three controls. 4. After all front panel LEDs flash rapidly for several seconds, release the controls.

Universal Audio Apollo x4 Specifications

General

Audio Interface Type	Thunderbolt 3
Number of Preamps	4
A/D Resolution	24-bit/192kHz
DSP	Yes
Phantom Power	Yes
Simultaneous I/O	12 x 18
Preamp Type	Unison
Software Compatibility	macOS, Windows
Power Supply	External Power Supply
Analog Inputs	4 x XLR/TRS combo
Analog Outputs	2 x Monitor TRS, 4 x Line TRS
Digital Inputs	ADAT, S/PDIF
Digital Outputs	ADAT, S/PDIF
Headphone Outputs	2

Summary

Introduction

Apollo x4 Thunderbolt 3 Audio Interface

Overview of the Thunderbolt 3 audio interface capabilities and connectivity.

Unison Technology Explained

Explanation of Unison technology for authentic mic preamp emulation.

Key Features and Technologies

Details on analog processing, UAD plug-ins, and next-gen A/D D/A conversion.

Advanced Functionality & Software

Covers monitoring, networking, amp emulations, and the Console app.

Apollo x4 Features

Key Features Summary

Highlights the main selling points and core capabilities of the Apollo x4.

Audio Interface & Mic Preamp Specs

Technical specifications for the audio interface and microphone preamplifiers.

Monitoring, DSP, Software, & Package Contents

Details on monitoring, UAD-2 DSP, Console software, and package contents.

Operational Overview

Audio Interface Functionality

Describes the core role of the Apollo x4 as a high-quality audio interface.

Realtime UAD Processing

Details on using UAD plug-ins in real-time with near-zero latency.

Console Software Operation

Overview of the Console application for controlling the Apollo x4.

UAD Plug-Ins in DAW & Standalone Use

How to use UAD plug-ins within a DAW and in standalone mode.

Apollo x4 Documentation

Manuals Overview and Resources

Guide to available Apollo and UAD manuals, including online access.

Additional Resources

Accessing Documentation & DAW Integration

Methods for accessing installed manuals and integrating with DAWs.

Quick Start Guide

Installation Notes & Setup

Instructions for physically installing and setting up the Apollo x4 unit.

Connection Notes

Thunderbolt 3 Connectivity

Requirements and guidelines for using Thunderbolt 3 connections.

Apollo Expanded Cascading

Information on linking multiple Apollo units for increased I/O and DSP.

Hardware Setup

Computer & Power Connections

Instructions for connecting the Thunderbolt 3 cable and power supply.

Software Setup

System Requirements & Installation

Prerequisites and steps for installing the UAD software.

Console Application Usage

Guide to using the Console application for hardware control and monitoring.

Connect Input Sources & Monitor System

Setting Hardware I/O Levels

Input Gain & Output Volume Adjustment

Procedure for setting input gain for mic, line, Hi-Z and output volumes.

Monitor Output Muting

Instructions for muting and unmuting monitor outputs.

Controls & Connectors

Controls Overview & Operating Modes

General explanation of controls and the two primary operating modes.

PREAMP Mode Operation

Details on using controls in PREAMP mode for input adjustments.

Channel Selection & Input Sources

How to select input channels, sources (Mic, Line, Hi-Z), and adjust gain.

Preamp Gain & Options

Explanation of the Level knob for gain and the available preamp option buttons.

MONITOR Mode Operation

Details on using controls in MONITOR mode for output adjustments.

Monitor Options & Controls

Explanation of monitor controls like TALK, DIM, ALT, FCN, MONO, MUTE.

Top Panel Controls

Level Knob Functionality

How the Level knob controls gain, volume, and Unison parameters.

Gain & Volume Indicator LEDs

Explanation of the LEDs surrounding the Level knob for signal level feedback.

Channel Indicators & Input Meters

Information on channel selection indicators and input signal metering.

Talkback Mic & PREAMP Button

Details on the built-in talkback microphone and the PREAMP mode button.

Monitor Button & Options Display

Function of the MONITOR button and the display for option states.

Option Buttons & Unison Integration

How option buttons control preamp/monitor functions and Unison parameters.

Preamp Options

INPUT Select & FILTER

Explanation of INPUT selection and the low-cut FILTER option.

+48V, PAD, & POLARITY Options

Details on phantom power, pad attenuation, and polarity inversion.

LINK Input Channels

How to link adjacent input channels for stereo operation.

Monitor Options

Monitor Control Functions

Explanation of TALK, DIM, ALT, and FCN monitor functions.

Front Panel Controls

Hi-Z Instrument Inputs

Details on the high-impedance instrument inputs for guitars and basses.

Headphone Outputs

Information on the stereo headphone outputs and their volume control.

Side Panel Features

Kensington Security Slot

Description of the security slot for anti-theft devices.

Rear Panel Connectors

Mic/Line Combo Inputs

Details on the four combo XLR/TRS inputs.

Monitor & Line Outputs

Information on monitor outputs and line outputs 3-6.

Power Supply & Optical I/O

Details on the power supply connection and the optical input/output ports.

ADAT Optical I/O Details

Explanation of ADAT Lightpipe protocol and channel availability.

S/PDIF Optical I/O Details

Explanation of S/PDIF protocol and sample rate conversion.

Thunderbolt 3 Port Connection

Instructions and requirements for connecting via Thunderbolt 3.

Specifications

System I/O Complement

Overview of the input/output channels and digital ports.

A/D - D/A Conversion

Specifications related to the analog-to-digital and digital-to-analog conversion.

Analog Input Specs

Detailed technical specifications for all analog input types.

Analog Output Specs

Detailed technical specifications for all analog output types.

Digital I/O Specs

Specifications for S/PDIF and ADAT digital connections.

Electrical Specifications

Mechanical Specifications

Package Contents

Hardware Block Diagram

Troubleshooting

Common Troubleshooting Items

Steps to diagnose and fix typical hardware and software problems.

Notices & Support Information

Warranty, Maintenance, & Repair

Information on product warranty, care, and how to obtain repair services.

Important Safety Information

Safety Precautions & Symbol Explanations

Guidelines for safe operation and explanations of warning symbols.

Compliance Information

Disclaimer

End User License Agreement

Trademarks

Copyright Information

Technical Support Resources

Knowledge Base & Video Support

Resources for self-help, including the knowledge base and YouTube tutorials.

Community Forums & Direct Contact

Information on user forums and direct contact methods for support.

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Universal Audio Apollo x4 User Manual

Table of Contents