Heritage Audio TT73

The Heritage Audio TT73 is a desktop microphone preamplifier and DI, inspired by the legendary 1073 and designed as a portable solution for on-stage use or location recording.

The TT-73 delivers the bright, vintage, and clean sound of the legendary Heritage Audio 1073. The preamp features separate input and output level controls, allowing the TT-73 to manage and saturate the input, creating a rich and colorful sound reminiscent of vintage consoles. The preamp is designed to amplify microphone signals up to +80 dB and line-level sources up to +50 dB. It includes a PAD switch with 20 dB attenuation of the microphone input before the input transformer to prevent overload when working with loud sources.

Heritage Audio TT73 Features

• Class A microphone preamp with up to 80 dB gain, selectable minimum input impedance (HI-LO), balanced and floating. Higher gain positions show higher impedance, ideal for vintage ribbon microphones.
• Class A 50 dB line preamp with bridged input impedance, balanced and floating.
• Discrete Class A direct input with ultra-high impedance J-Fet on a high-quality Neutrik Jack connector. The DI circuit is before the microphone input transformer, so in DI mode the transformer is engaged.
• DI THRU jack with a ground lift switch.
• Single-ended Class A output stage using 2N3055 transistors with high gain.
• Separate gold-plated Neutrik XLR connectors for microphone and line inputs.
• Gold-plated Neutrik XLR output.
• PAD: 20 dB
• High-pass filter: Active fully discrete Class A 3rd order Bessel high-pass filter at 80 Hz. Slope of 18 dB/octave.
• OUTPUT control allows for preamp overload.
• Internal silent power supply accepting worldwide voltages from 100 to 240 V.
• Carnhill input and output transformers.
• 3 stages of gain, authentic modular design of the B283 gain card.
• Marconi-style control knobs and vintage-style engraved buttons.

Heritage Audio TT73 Specifications

• Microphone input impedance: High=1200 Ω minimum; Low=300 Ω minimum. Higher gain positions gradually have greater impedances, optimum for low gain ribbon mics. Input is transformer balanced and floating.
• Line input impedance: 10 kΩ bridging, transformer balanced and floating.
• Output impedance: Less than 75 Ω, transformer balanced and floating, to drive a load of 600 Ω.
• D.I. input impedance: Greater than 2 MΩ, unbalanced.
• Maximum output: Greater than +26.5 dBu into 600 Ω (internally terminated).
• THD: Less than 0.025% at 1 kHz, Less than 0.05% at 100 Hz.
• Frequency response: 20 Hz (+0.3 dB) to 20 kHz (-0.2 dB).
• Maximum Gain: Slightly greater than 80 dB.
• Power supply: Internal no-noise PSU, accepting worldwide voltages from 100 V to 240 V.
• Dimensions (W x H x L): 238 mm x 95 mm x 250 mm.
• Weight: 3.020 Kg.