Heritage Audio 73 JR II｜500 Series Preamp with Classic 1073 Character
The Heritage Audio 73 JR II condenses the classic 1073 preamp circuit into a single-slot 500 Series module, featuring a fully discrete Class A design and Carnhill transformers. It offers Mic/Line/DI three-mode inputs, up to approximately 80 dB of microphone gain, and a switchable high-pass filter, plus an Output Trim to easily achieve a warm, powerful British tone.
Key Features
- 500 Series single-slot fully discrete Class A microphone preamp
- Based on the classic 1073 acoustic design, using UK Carnhill input/output transformers
- Mic / Line / DI three input modes for quick adaptation to various sources
- Up to approximately 80 dB microphone gain with stepped gain control for high repeatability
- Switchable +48V phantom power and phase reverse for more flexible hookup and recording
- Switchable high-pass filter to effectively reduce low-frequency rumble and proximity effect
- Independent Output Trim lets you drive the transformer for tonal saturation while managing level
- Front-panel Hi‑Z instrument input for convenient direct guitar/bass recording
- Compatible with all rack systems conforming to the 500 Series specification
Specifications
| Product Type | 500 Series Mic Preamp / DI |
| Channels | Mono |
| Circuit Topology | Fully discrete Class A, classic 1073-style |
| Transformers | Carnhill input and output transformers |
| Input Modes | Mic / Line / DI (Hi‑Z instrument input) |
| Microphone Gain | Up to approximately 80 dB, stepped control |
| Phantom Power | +48 V, switchable |
| Phase | Phase reverse switch |
| High-pass Filter | Switchable high-pass filter |
| Output Control | Output Trim (tone drive and level management) |
| Slots Occupied | 1 slot (500 Series standard) |
| Power Requirements | Complies with 500 Series rack specification (±16 V and +48 V provided by the rack) |
