Introducing Heritage Audio’s HA-81A EQ: a new mix of 2 classic console circuits.
The HA-81A EQ Elite is a channel strip that combines an all discrete, Class A 73-style mic preamp with an extremely versatile and musical console style equalizer — arguably the trick for obtaining instant classic sound for all recording engineers.
The mic preamp that meets the demands.
The HA-81A’s preamp section is an 80 dB, all discrete Class A design with Carnhill St Ives input and output transformers, exactly the same ones found in the other Elite Series modules.
The preamp features gain, output trim, -20 dB pad, polarity reverse, and +48 V phantom power.
The best console´s style equalizer ever made.
The HA-81’s equalizer section is an exceptionally musical 4 band, inductor-based equalizer with high and low pass filters. Where 3 band equalizers such as the typical 73-style exceed at musicality but may be short of features, the HA-81A EQ excels at both equally. Extreme control over Shelf or Bell response curves on the high and lows, dual Q on both mid bands, with dedicated high and low mid bands, and a range of 40 frequency selections to choose from.
Hybrid design. Heritage quality.
The Heritage HA-81A EQ utilizes only rotary switches and precision, concentric potentiometers. And like all of the products in our Elite range, the HA-81A EQ is built with the most cutting edge methods in manufacturing and design, without ever compromising audio quality or cutting corners — all at the Heritage Audio headquarters in Madrid-Spain.
Specifications
Microphone input impedance: HI=1200 Ω minimum, LO=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.
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) – EQ Off.
Maximum Gain: Slightly greater than 80 dB.
Equivalent Input Noise: Less than -125 dBu at 80 dB mic gain.
Output stage noise: Less than -100 dBu.
Power consumption: Less than 150 mA @48 V DC.