Heritage Audio HA-73EQ | Classic '73 Tone Class A Preamp with 3-Band EQ
The HA-73EQ combines the classic '73-style preamp with a highly musical three-band EQ, preserving the authentic British character and a warm, full-bodied saturation. Featuring UK Carnhill transformers, up to approximately 80 dB of gain, and a front-panel Hi‑Z DI, it can quickly shape vocals, guitar, or drums to capture the classic tone.
Key Features
- Classic '73-style Class A microphone/line preamp integrated with a three-band EQ — one unit for front-end amplification and tone shaping
- UK Carnhill input/output transformers, delivering a thick, warm, musically saturated British character
- Microphone gain up to approximately 80 dB, easily drives dynamic and ribbon microphones while maintaining low noise
- 12 kHz high-frequency design, six selectable mid frequencies, and selectable low-frequency bands to recreate the musical curves of the classic '73 style
- High-pass filter with 50/80/160/300 Hz settings to effectively clean low-frequency noise and stage rumble
- Front-panel Hi‑Z instrument DI input for direct guitar/bass connection, yielding rounded, detailed direct-recorded tones
- Output Trim control allows pushing the preamp into saturation or keeping a clean dynamic range while maintaining optimal gain staging
- Useful switches including 48V phantom power, phase reverse, and EQ bypass for a simple, flexible workflow
- 1U rack design with metal chassis and through-hole discrete component construction — durable and easy to service
- Designed for professional studios and live sound; from vocals to drum kits you can quickly achieve the classic '73 tone
Technical Specifications
| Brand | Heritage Audio |
| Model | HA-73EQ |
| Type | Mono Class A mic/line preamp + 3-band EQ |
| Preamp Gain | Microphone up to approx. 80 dB, includes Output Trim control |
| Equalizer | Classic '73-style three-band EQ: fixed high band, selectable mid and low bands, with musical boost/cut |
| EQ Frequencies | HF: 12 kHz; MF: 360 / 700 Hz / 1.6 / 3.2 / 4.8 / 7.2 kHz; LF: 35 / 60 / 110 / 220 Hz |
| High-Pass Filter | Selectable 50 / 80 / 160 / 300 Hz |
| Transformers | UK Carnhill input/output transformers |
| Inputs | XLR mic / line; front-panel 1/4" Hi‑Z instrument DI |
| Outputs | XLR balanced main output |
| Function Switches | 48V phantom power, phase reverse, EQ bypass, Mic/Line selection |
| Chassis Size | 1U 19" rack width |
| Power | External universal power supply (100–240 V AC) |
