Channels 1-2 offer combo XLR-1/4" mic/line connections and a Hi-Z switch (for guitar and bass), while channels 3-4 offer XLR or 1/4" inputs. Channels 1-4 include inserts, and single-knob compression. Channels 5/6, 7/8, 9/10 offer two 1/4" inputs, while channel 11/12 uses a 3.5mm stereo input. Channels 1-10 feature gain controls, a 3-band EQ, an aux (monitor) send, a dedicated FX send, pan, mute, and level faders. Engaging channel 11/12's USB 3-4 switch will override the 3.5mm input and enable the USB return from a computer.

Each channel strip includes button selectors for Main L/R, Sub 1/2, and Solo (PFL). The master section offers dedicated faders for Main, Sub, and FX. Main output connectors include both XLR and 1/4", while sub and control room outputs use 1/4" connector. A dedicated 1/4" TRS headphone output includes its own independent level control. Other features include an input / USB 1-2 blend control, a dedicated FX output, an FX level fader, and an FX mute, which can also be controlled via the 1/4" footswitch input.

Features
Professional Sound Quality
Equipped with 7 Onyx Mic Pres offering up to 60 dB of gain and ultralow noise performance
GigFX Effects Engine with 24 different FX options, from reverbs to delays and more
Essential Mixing Tools
3-band EQ on all channels
Channels 5 to 10 feature mic inputs and stereo line inputs for maximum versatility
Hi-Z switches allows direct connection of guitars, basses, and other instruments
100 Hz low-cut filter and 48V phantom power on all mic channels
Stereo 3.5mm input on channel 11/12
Aux/Monitor output with dedicated per-channel send control
Stereo Subgroup output bus with per-channel assignment
Headphone output with separate level and blend control
Insert jack on channels 1–4
Pre-Fader solo on all channels
Footswitch input for FX Mute
Single-knob compression helps keep your input levels in check
24-Bit / 192 kHz 2x4 USB Recording Interface
2x4 USB I/O allows you to create two custom mixes on your computer to send back in to the mixer
Perfect for live performance recording, music playback, live streaming, and more
Latency-Free Monitoring
Easily blend between monitoring your computer’s output and a direct feed from the mixer
Professional Production Content
Pro Tools | First and Waveform OEM professional software and plugin packages included
The DAW Essentials Bundle for Waveform OEM includes 16 powerful plugins like Equalizer, Compressor, Reverber8, and Limiter
Signature Rugged Design
Mackie built-like-a-tank design
Solid steel chassis protects your investment
Tough ABS side protection

Mackie PROFX12V3 Specs
Mixer
Number of Analog Input Channels 12
Number of Mic Preamps 7
Analog Output Channels 2 x Stereo Master Output
1 x Stereo Control Room/Monitor Output
1 x Stereo Bus/Subgroup Output
1 x Mono Aux Send Output
1 x Mono FX Send Output
1 x Stereo Headphone Output
Mix Routing Stereo Main Mix
Stereo Aux Bus/Subgroup
Faders None
Meters Main Meter:
2 x 12-Segment LED
Meter Range Main Meter:
-30 dB to +15 dB Plus Peak/Clip
Signal Processing
Gain/Trim Range -20 dB to +60 dB
EQ 3-Band EQ
EQ Parameters Low: ±15 dB at 80 Hz
Mid: ±15 dB at 2.5 kHz
High: ±15 dB at 12 kHz
Filters High-Pass: 100 Hz, 18 dB/Octave
Built-In Effects 24 x Effect (Type Unspecified)
Digital Audio
Bit Depth 24-Bit
Performance
Frequency Response Mic Input to Output:
20 Hz to 30 kHz +0/-1 dB (Unity Gain)
Max Input Level +22 dB
Output Level Main Output:
+28 dBu at Max Gain
All Other Output:
+22 dBu at Max Gain
I/O Impedance Mic Input:
3.3 Kilohms
Insert Return:
10 Kilohms
Line Input:
≥ 20 Kilohms
Headphone Output:
25 Ohms
Main Output:
120 Ohms (Unbalanced)
240 Ohms (Balanced)
Crosstalk Adjacent Inputs:
-90 dB at 1 kHz
Input to Output:
-80 dB at 1 kHz
Fader Off:
-75 dB at 1 kHz
Muted:
-90 dB at 1 kHz
CMRR 70 dB at Max Gain (1 kHz, Mic In to Main Out)
EIN -126 dBu at Max Gain (150-Ohm Input)
Noise Floor All Outputs:
-95 dBu (Master Level at -∞, Channel Levels at -∞)
-80 dBu (Master Level at Unity, One Channel Level at Unity)
THD+N Mic Input to Main Output:
< 0.03% (+4 dBu)
Connectivity
Analog Inputs 2 x Combo XLR-1/4" 3-Pin Balanced/Unbalanced Mic/Line/Hi-Z Input
5 x XLR 3-Pin Balanced Mic Input
5 x 1/4" TRS Balanced/Unbalanced Line Input (5 Stereo Pairs)
1 x 1/8" / 3.5 mm TRS Unbalanced Stereo Line Input (1 Stereo Pair)
1 x 1/4" TRS Footswitch Input
Analog Outputs 2 x XLR 3-Pin Balanced Stereo Main Output
2 x 1/4" TRS Balanced Stereo Main Output
2 x 1/4" TRS Balanced Stereo Control Room/Monitor Output (1 Stereo Pair)
2 x 1/4" TRS Balanced Stereo Subgroup Output (1 Stereo Pair)
2 x 1/4" TRS Balanced/Unbalanced Aux/Monitor Send
1 x 1/4" TRS Unbalanced Stereo Headphone Output
Phantom Power +48 V, Selectable On/Off (Applied to All Inputs)
Digital I/O None
MIDI I/O None
USB 1 x USB-B 2.0()
USB I/O Capacity 2 x Input / 4 x Output
Bluetooth None
Compatibility
OS Compatibility macOS
Windows
*As of March, 2022: Check with manufacturer for the most up-to-date compatibility
Power
AC Input Power Universal:
100 to 240 VAC, 50 / 60 Hz
AC Power I/O 1 x IEC Input
Power Consumption 30 W
Physical
Rack Mountable No
Dimensions 3.9 x 13 x 14.8" / 8.1 x 33 x 37.5 cm
Weight 7.9 lb / 3.6 kg