The Warm Audio WA273 is a dual-channel, Class-A microphone preamp designed to provide up to 80 dB of gain for engineers, producers, musicians, and vocalists in mobile-recording rigs and home, project, and commercial studios. It features custom Carnhill transformers and is wired and assembled by hand to deliver the sound and functionality of classic British '73-style preamps.

Its inputs include balanced XLR and 1/4" TRS jacks and two front-panel 1/4" TS instrument inputs. Input impedance, polarity, ground lift, and phantom power are switchable. Connect an outboard compressor or equalizer via the 1/4" TS insert send and return jacks. Balanced XLR and 1/4" outputs are fed by output level controls and allow compatibility with most audio interfaces and mixing consoles. The selectable high-pass filter can be set to 50 Hz, 80 Hz, 160 Hz, or 300 Hz for management of unruly bass frequencies.

• Occupies 1 RU
• Dual-channel, Class-A mic preamp wired and assembled by hand
• Created through years of R&D, careful reverse-engineering, and countless hours of auditioning
• Designed to function and sound like a classic '73-style preamp
• Fully discrete, transformer-balanced signal path
• Custom Carnhill transformers saturate sweetly when pushed
• Tantalum and polystyrene capacitors in the signal path and an output transistor choice that is smooth in high-gain settings
• Stepped mic pre gain
• Inductor-based selectable high-pass filter
• Balanced XLR and 1/4" inputs and outputs
• Front-panel 1/4" TS instrument inputs
• 1/4" TS insert sends and returns
• Output controls with 5-segment LED meters

Specifications:

• Rack Height: 1 RU
  
• Number of Channels: 2
  
• Inputs: 2 x XLR 3-pin (balanced). 2 x 1/4" TRS (balanced). 2 x 1/4" TS (unbalanced)
  
• Outputs: 2 x XLR 3-pin (balanced). 2 x 1/4" TRS (balanced)
  
• Phantom Power: 48 V
  
• High-Pass Filter: Off, 50 Hz, 80 Hz, 160 Hz, or 300 Hz
  
• Gain Range: Up to 80 dB
  
• Frequency Response: 20 Hz to 20 kHz (±0.5 dB)
  
• Equivalent Input Noise: -111 dBu (unweighted)
  
• Power Requirement: 115/230 V, 50/60 Hz
  
• Dimensions: 19.0 x 1.8 x 11.5" / 48.3 x 4.4 x 29.2 cm
  
• Weight: 14 lb / 6.4 kg
  
• Specialties: 2 x 1/4" TS insert sends. 2 x 1/4" TS insert returns. 2 x 5-segment LED meters. Switches for phantom power, polarity, impedance, input source, insert, power, and ground lift
  
• Package Weight: 14 lb
  
• Box Dimensions (LxWxH): 25 x 16 x 5"