Universal Audio Apollo x4 Gen 2 STU (Desktop) + SoundID Apollo version bundle

scan pro audio exclusive bundleThis exclusive package pairs the Universal Audio Apollo x4 Gen 2 STU audio interface with Sonarworks SoundID Reference for Speakers & Headphones, plus the Apollo Monitor Correction Add-On—giving you a complete, professional-grade solution for recording, mixing, and critical listening.

At the heart of the bundle, the Apollo x4 Gen 2 ESS delivers elite-class audio conversion, real-time UAD processing, and the trusted Unison™ preamps that bring iconic analog character straight into your workflow. Whether you're tracking vocals, instruments, or producing entirely in-the-box, it provides the clarity and power modern studios rely on.

To ensure what you hear is truly accurate, Sonarworks SoundID Reference calibrates your speakers and headphones, correcting frequency imbalances in your room or monitoring setup. The included Apollo Monitor Correction Add-On integrates this correction directly within the Apollo ecosystem, creating a seamless and low-latency monitoring experience. Together, this bundle eliminates guesswork from your mixes—so your music translates perfectly across all systems, from studio monitors to streaming platforms.

what's included? • Universal Audio Apollo x4 Gen 2 STU
• Sonarworks SoundID Reference for Speakers & Headphones and Apollo Monitor Correction Add-On bundle (download only)

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

Get the Most Powerful Desktop Apollo EverUniversal 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 PreampsWith 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.

at a glance • 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
• *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

a library of over 200 UAD plug-insRight 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 BeforeNow 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 AppJust 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 MissionCombine 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 GrowBuild 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.**

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 (6) • Brigade Chorus Pedal
•Galaxy Tape Echo
•Precision Delay Mod
•Precision Delay Mod L
•Studio D Chorus
•Waterfall Rotary Speaker

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

Create, mix and deliver with confidenceCalibrate your headphones and speakers with SoundID Reference software to trust every mixing decision.

What is it?SoundID Reference is a standalone app and a DAW plugin that calibrates speakers and headphones to deliver an accurate studio reference sound.

who's it for?Made for audio engineers, producers, musicians, DJs, composers, sound designers, game developers, and audiophiles.

What it does?SoundID Reference ensures perfect translation so you can create music that sounds great on phones, laptops, earbuds, or wherever else its played.

ResultsBy working with the same reference sound with your colleagues and clients, you can save time and money, no matter the distance or gear you have.

How it works?Even the best speakers can't compensate for the acoustics of a poorly designed room. SoundID Reference compensates for that by measuring the frequency response of your room and speakers to create a calibration profile. For headphones - simply apply a pre-made calibration profile available in the software. With calibration applied, your music will sound great everywhere.