Thunderbolt audio interface. 18 x 24 Thunderbolt 3 audio interface with class-leading 24-bit/192 KHz conversion (backwards compatible with Thunderbolt 1 and 2 on Mac). Realtime UAD HEXA Core Processing for tracking through UAD plug-ins at near-zero latency, regardless of audio buffer size. Record through 4 Unison-enabled mic/line preamps — giving you fully authentic preamp emulations from Neve, API, Manley, SSL, and more. Surround monitor controller up to 7. 1 format. Includes “Realtime Analog Classics Plus” UAD plug-in bundle featuring UA 610-B Tube Preamp; Legacy Pultec EQ, LA-2A, and 1176 compressors; Marshall Plexi Classic; Ampeg SVT-VR Classic and more. UAD HEXA Core processing onboard for additional mixing horsepower for Pro Tools, Logic, Cubase, Ableton, and other major DAWs. Combine up to 4 Thunderbolt-equipped Apollos and 6 total UAD devices. Selectable +24 dBu operation for easy compatibility with professional mixing consoles and tape machines. Convenient front panel monitoring functions including Alt Speakers, Talkback mic, and assignable Dim or Mono. Line inputs: 8 x balanced 6,3 mm jack. Microphone inputs: 4 x balanced XLR. Instrument (Hi-Z) inputs: 2 x unbalanced 6,3 mm jack. Digital inputs (Optical TOSLINK): ADAT: 8 channels @ 44. 1 – 96 kHz. ADAT: 4 channels @ 176. 4 – 192 kHz. Digital inputs (RCA): S/PDIF: 2 channels @ 44. 1 – 192 kHz. A to D conversion: Mic preamps: Dynamic range: 122 dB (A-weighted) THD+N: -115 dB (0. 00019%). Frequency response: 20 Hz – 20 kHz, ±0. 05 dB. Line inputs: Dynamic range: 123 dB (A-weighted). THD+N: -113 dB (0. 00022%). Frequency response: 20 Hz – 20 kHz, ±0. 04 dB. Line outputs: 8 x balanced 6,3 mm jack. Monitor outputs: 2 x balanced 6,3 mm jack. Headphone outputs: 2 stereo 6,3 mm jack. Digital outputs (Optical TOSLINK): ADAT: 8 channels @ 44. 1 – 96 kHz. ADAT: 4 channels @ 176. 4 – 192 kHz. Digital outputs (RCA): S/PDIF: 2 channels @ 44. 1 to 192 kHz. D to A conversion: Line outputs: Dynamic range: 127 dB (A-weighted). THD+N: -118 dB (0. 00011%). Frequency response: 20 Hz – 20 kHz, ±0. 07 dB. Monitor outputs: Dynamic range: 129 dB (A-weighted). THD+N: -118 dB (0. 00012%). Frequency response: 20 Hz – 20 kHz, ±0. 06 dB. Headphone outputs: Dynamic range: 125 dB (A-weighted). THD+N: -102 dB (0. 00080%). Frequency response: 20 Hz – 20 kHz, ±0. 05 dB. System requirements: Thunderbolt 3 cable (not included). Internet connection to download software and authorize UAD plug-ins. 6 gigabytes available storage. Quad Core i7 or better processor recommended. MAC: Available Thunderbolt 1, 2, or 3 port. Thunderbolt 1 and 2 connections require an Apple Thunderbolt 3 to Thunderbolt 2 Adapter (not included). MacOS 10. 12 Sierra or 10. 13 High Sierra. PC: Available Thunderbolt 3 port. Windows 10 Fall Creators Update (64-Bit Edition).