Universal Audio Apollo x4 Gen 2 STU (Desktop/TB3/MAC/WIN)

Create with the world’s most powerful desktop audio interface.

Record and mix larger sessions and hear every detail with the next generation of UA’s Apollo x4 interfaces, featuring highest-resolution audio conversion, four Unison™ mic preamps, and QUAD Core DSP processing letting you record in realtime through UAD plug-ins from Neve, Manley, Avalon, SSL, and hundreds more.

Trusted by top artists and producers the world over, Apollo x4 levels up your productions with timeless sound and legendary UA craftsmanship, built to inspire your next collaboration.

Key Benefits

Hear next generation audio conversion with the widest dynamic range and lowest distortion of any Apollo
Experience analog tones with UnisonTM preamps, letting you record in realtime through authentic emulations of Neve, API, Avalon, Manley, Fender, and more
Access the full library of 200+ UAD DSP and Native plug-ins, including award-winning titles like Capitol Chambers, Sound City Studios, EL8 Distressor, and more
Mix with confidence in any room or through headphones using Apollo Monitor Correction powered by Sonarworks®*
Use Auto-Gain to set your levels across multiple inputs in seconds and never miss the take
Hear all the low-end detail in your mixes using bass management to add a subwoofer to your monitor setup
Quickly set up low-latency cues, plug-in scenes, and immersive audio monitoring with the UAD Console app
Get thousands of dollars in award-winning UAD plug-in titles from Auto-Tune, Fairchild, Teletronix, and more with a choice of Essentials+ or Studio+ Editions
Get the Most Powerful Desktop Apollo Ever

Universal Audio built Apollo x4 to expand on the gold-standard Apollo Twin, the interface that single-handedly revolutionized home and project studio recording. With its expanded I/O count, unprecedented dynamic range, and elite-class 24-bit / 192 kHz audio conversion — now with enhanced monitoring — Apollo x4 puts the sound of the stars in reach for project studios and collaborators.

Record Through Iconic Preamps

With four Unison™ preamps and dual front panel Hi‑Z instrument inputs, Apollo x4 lets you track in realtime through preamp and channel strip plug-ins from Neve, Manley, API, and dozens more, giving you the same rich analog textures used on the greatest recordings of our time.

Mix with Authentic Analog Sounds

Right out of the box, Apollo x4 gives you the tools used in the world’s biggest recording studios. Along with included Teletronix LA-2A compressors, Pultec EQs, and amps from Marshall and Ampeg — you can tap into the entire library of over 200 UAD plug-ins and unlock proven hit-making sounds like Ocean Way Studios, Capitol Chambers, and many more.

Hear the Details Like Never Before

Now in its Gen 2 design, Apollo x4 features UA’s highest-resolution D/A converters ever paired with Apollo Monitor Correction powered by Sonarworks.® This means that when you playback your audio through monitors or headphones, you’ll not only hear the most pristine representation of your recordings, there will be no surprises when you listen to your final mix or master.

Find Your Flow in the UAD Console App

Just like an analog studio, where a console is the heart of the workflow, Apollo x4 has a powerful digital mixing engine where you control plug-in routing and monitoring. And with the latest features like Auto-Gain, Bass Management and Plug-In Scenes, it’s easy to find a flow that fits your needs.

A Hybrid System, Made for Your Mission

Combine Apollo x4’s QUAD Core DSP with native processing from your host computer to produce large sessions with complex plug-in chains — a powerhouse hybrid workflow that outpaces any native-only recording setup.

Expand Your Studio as You Grow

Build your studio by linking up to four Thunderbolt Apollo interfaces with up to 128 channels of premium I/O to your DAW, and control it all from your desktop using Apollo x4. So no matter how far your music takes you, an Apollo will always be in reach.**

Key Features

12 x 18 Thunderbolt audio interface with QUAD Core DSP plug-in processing
Four UnisonTM mic preamps, two Hi-Z instrument inputs, optical Toslink I/O (ADAT or S/PDIF)
Two 1/4" monitor outs, four 1/4" line outs (ALT 1 / 2), two 1/4" TRS headphone outs
Elite-class Apollo X Gen 2 converters with 24-bit / 192 kHz resolution
Enhanced D/A for critical monitoring and playback with 129 dB dynamic range
Calibrate your main monitor and headphone outputs with Apollo Monitor Correction powered by Sonarworks®*
Fully-featured monitor controller with alternate speaker switching and integrated talkback for easy communication with talent
Updated UAD Console app featuring Auto-Gain, Plug-In Scenes, subwoofer integration with Bass Management, immersive audio support, and more
Onboard DSP supports over 200 UAD plug-ins via VST, AU, and AAX 64 formats in all major DAWs
Includes up to 50+ UAD plug-ins with Essentials+ or Studio+ Editions
Compatible with LUNA, Logic Pro, Pro Tools, Cubase, Ableton Live, and more**
Expandable with Thunderbolt Apollo interfaces or select models over Dante
Free industry-leading technical support from knowledgeable audio engineers
*Coming Q4 2024, requires Apollo Monitor Correction Add-on and SoundID Reference licenses, available from sonarworks.com

**For full compatibility information, refer to help.uaudio.com

Included Plug-Ins in Studio+ Edition

Channel Strips & Preamps (9)
Avalon VT-737sp Channel Strip
Century Tube Channel Strip
CS-1 Channel Strip
Helios Type 69 Preamp & EQ
Manley Reference Microphone Preamp
Precision Channel Strip
UA 610-A Preamp & EQ
UA 610-B Preamp & EQ
V76 Preamplifier
Compressors / Limiters (17)
dbx 160 Compressor / Limiter
Empirical Labs Distressor
Fairchild 670 Legacy
Fairchild 660 Compressor
Fairchild 670 Compressor
Teletronix LA-2 Classic Leveler
Teletronix LA-2A Gray Classic Leveler
Teletronix LA-2A Silver Classic Leveler
Teletronix LA-2A Legacy Leveling Amplifier
Teletronix LA-3A Classic Audio Leveler
UA 1176 Rev A Classic Limiter
UA 1176AE Classic Limiter
UA 1176LN Rev E Classic Limiter
UA 1176LN Legacy
UA 1176SE Legacy
UA 175B Classic Limiter
UA 176 Classic Limiter

Equalizers (6)
Helios Type 69 Legacy EQ
Pultec EQP-1A Legacy EQ
Pultec EQP-1A Passive EQ
Pultec HLF-3C Passive EQ
Pultec MEQ-5 Passive EQ
Pultec Pro Legacy EQ

Special Processing (7)
Auto-Tune Realtime Access
Auto-Tune Realtime Advanced
Auto-Tune Realtime X
Oxide Tape Recorder
Precision Enhancer Hz
Studer A800 Multichannel Tape Recorder
Verve Analog Machines Essentials

Instruments (6)
Electra 88 Vintage Keyboard Studio
Moog Minimoog
Opal Morphing Synth
PolyMAX Polyphonic Synth
Ravel Grand Piano
Waterfall B3 Organ

Delay & Modulation (5)
Brigade Chorus Pedal
Galaxy Tape Echo
Precision Delay Mod
Precision Delay Mod L
Studio D Chorus

Reverbs & Rooms (4)
Lexicon 224 Digital Reverb
Precision Reflection Engine
Pure Plate Reverb
RealVerb Pro Custom Room Modeler

Guitar & Bass (3)
Ampeg SVT-VR Classic Bass Amplifier
Marshall Plexi Classic Amplifier
Raw Distortion

US and EU parcels ship via UPS, ETA 1-7 working days from pickup day zero. That also applies to most locations worldwide.

All shipments are fully insured.

Bigger shipments requiring pallets or custom made crates ship to US, CA, JP, CN, AU and other outside of EU locations via DHL Air Freight, ETA is normally approx. 7-14 working days from pickup day zero.

Big shipments inside EU ship via different freight companies, recently mostly via ACE Logistics. Freight forwarders can use different courier companies for deliveries to final destinations.

Palletising and crating time can vary depending on the size of the shipment and packaging queue. We pack all our shipments with great care.

You are most welcome to pick your order up yourself from our Retrosonic Pro Audio showroom, studio and warehouse in Tallinn, Estonia.

We ship worldwide – contact us for a personal shipping quote or any other questions.

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