Heritage Audio ELITE Series User manual

USER MANUAL
MONO CHANNEL CLASS A
MICROPHONE PREAMP / 81- STYLE EQ
ELITE SERIES
HA-81A EQ
August/2022)Rev.)1.0.)

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INTRODUCTION
CONTENTS
DESCRIPTION
GETTING STARTED
APPLICATIONS!
SPECIFICATIONS!
SIGNAL FLOW!
TROUBLE SHOOTING
WARRANTY STATEMENT!
REGISTRATION!
RECALL SHEETS
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TABLE OF CONTENTS
Thank you for choosing the Elite Series HA-81A EQ. Heritage Audio is dedicated to bringing you ´the sound of
yesterday for tomorrow´. We specialize in capturing that unique, enticing sound that everybody has fallen in love with.
For years engineers, producers and musicians have been yearning for that classic vibe. Usually the only option is to
search for old, used original equipment that is almost always in a questionable state of operation. This brings with it a
whole lot of other issues, making the experience less than desirable. Not to mention the very high prices asked for this
equipment, which makes them virtually unobtainable for the great majority. Now it´s possible to obtain that same sound
with a brand new piece that will give you all the problem-free, heavy-duty use you´ll need for years of music making
history.
Peter Rodriguez
CEO!
Heritage Audio - Madrid, Spain
INTRODUCTION
© 2022 Heritage Audio S.L. is the sole owner of the copyright of all information and drawings contained in this manual which are not to be copied or
reproduced by any means or disclosed in part or whole to any third party without written permission.
Heritage Audio reserves the right to alter specifications without notice. The information in this manual has been carefully checked and is believed to
be accurate at the time of publication. However, no responsibility is taken by us for inaccuracies, errors or omissions nor any liability assumed for any
loss or damage resulting either directly or indirectly from use of the information contained within it.
HA-81A EQ
AC POWER CORD EU & US
POWER SUPPLY HA-PSU04

DESCRIPTION
Heritage Audio’s HA-81A EQ is a mix of 2 of the most famous classic console circuits, combining one´s preamp with the
other´s EQ section. It´s a channel strip built with an all discrete, Class A 73-style mic preamp with an extremely versatile
and musical console style equalizer — arguably a popular trick for recreating that classic sound sought by all recording
engineers, artists and producers.
The HA-81A’s preamp section is a powerful 80dB, all discrete Class A design with Carnhill St Ives input and output
transformers, the same ones found in the other Elite Series modules. The preamp features a 2-stage, stepped gain
knob for easy recall and a fully adjustmentable output trim. Also available are a -20 db pad, a polarity reverse button,
+48 V phantom power and switchable impedance for optimizing the preamp’s response to a variety of microphones.The
HA-81A EQ preamp section delivers a solid Class A sound with a harmonically rich bottom end, musical but focused
mids as well as sparkling and airy highs."
The HA-81A EQ includes a very comprehensive equalizer section with an exceptionally musical 4 band, inductor-based
equalizer. We´ve also incorporated high quality 18 dB 3-pole high and low pass filters for total tonal control. 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. There is also control over Shelf or Bell response curves on the high and lows, dedicated high and low mid bands
with dual Q options, and a range of 40 frequency selections to choose from
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.
All in all the HA-81A EQ is a fantastic choice, providing a professionally processed signal that´ll take your recordings to
the next level.
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GETTING STARTED
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FRONT
REAR
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EQL
Turns Equalizer ON and
OFF
LINE BUTTON
Switches from MIC/D.I. to
LINE input
MIC INPUT IMPEDANCE
(LOZ)
1200 Ωor 300 Ωwhen
pressed
HI SHELF BOOST/CUT
±15 dB of Boost or Cut
BELL BUTTON
Turns Bell shape ON or
OFF
LOW MID BAND
BOOST/CUT
±15 dB of Boost or Cut
1
2
3
4
POWER INPUT
To Be Connected to the HA PSU04
Power Supply
LINE OUTPUT
Male XLR Connector
LINE INPUT
Female XLR Connector
MIC INPUT
Female XLR Connector
All XLRs are:
Pin 1: GND!
Pin 2: Hot!
Pin 3: Cold
1
2
3
3
2
1
GND!
Hot (+)!
Cold (-)
MALE XLR
FEMALE XLR
D.I. Jack:
Tip: Signal!
Sleeve: Ground!
Tip=Signal
Sleeve=Ground/Shield
Tip
Sleeve
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3
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5
8
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2
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HI MID BAND BOOST/
CUT
±15 dB of Boost or Cut
BELL BUTTON
Turns Bell shape ON or
OFF
LOW SHELF BOOST/
CUT
±15 dB of Boost or Cut
LOW PASS FILTER
18 dB/Octave 3-pole Filter
at selectable frequencies:
3.9, 5.6, 8.2, 12, and 15
kHz or OFF position to
remove the filter from the
signal path
PHASE BUTTON
Flips phase 180º
POWER
Activates unit
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2
3
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D.I. INPUT
High Impedance Class A
JFET
PHANTOM POWER
SWITCH
Activates 48 V
MIC PAD BUTTON
20 dB Reduction Ahead of
Input Transformer
INPUT GAIN SWITCH
5 dB Steps from 30 to 80
HI SHELF
FREQUENCIES
Selectable Frequencies:
3.3, 4.7, 6.8, 10 and 15
kHz
HI Q BUTTON
Push to create a sharper
bandwidth
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10
11
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HI MID BAND
FREQUENCIES
Selects from 10
frequencies: 1.5 kHz to
8.2 kHz or OFF position
to remove the band from
the signal path
LOW MID BAND
FREQUENCIES
Selects from 10
frequencies: 220 Hz to
1200 Hz or OFF position
to remove the band from
the signal path
HI Q BUTTON
Push to create a sharper
bandwidth
LOW SHELF
FREQUENCIES
Selects frequency for the
Low Shelf: 33, 56, 100,
180 and 330 Hz or OFF
position to remove the
band from the signal path
HI PASS FILTER
18 dB/Octave 3-pole Filter
at selectable frequencies:
27, 47, 82, 150 and 270
Hz or OFF position to
remove the filter from the
signal path
OUTPUT ATTENUATOR
Attenuates from 0 to
Infinity
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3
2
1

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MIC
APPLICATIONS
D.I.
LINE
USB - COMPUTER
USB - COMPUTER
GUITAR FX PEDAL
OUTPUT
D.I. INPUT
USB - COMPUTER
LINE OUTPUT - KEYBOARD
LINE INPUT
ACTIVATE LINE SWITCH
OUTPUT
LINE INPUT - AUDIO INTERFACE
LINE INPUT - AUDIO INTERFACE
LINE INPUT - AUDIO INTERFACE
CONDENSER MIC
OUTPUT
MIC INPUT
ACTIVATE +48 V FOR CONDENSER MIC

SPECIFICATIONS
•Microphone input impedance: High=1200 Ωminimum; Low=300 Ωminimum. Higher gain positions gradually have
greater impedances, optimum for low gain ribbon mics. Input is transformer balanced and floating.
•Line input impedance: 10 kΩbridging, transformer balanced and floating.
•Output impedance: Less than 75 Ω, Carnhill transformer balanced and floating, to drive a load of 600 Ω(Factory
terminated).
•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).EQ Off.
•Maximum Gain: Slightly greater than 80 dB.
•Output stage noise: Less than -100 dBu.
•Power consumption: Less than 150 mA @48 V DC.
•Dimensions (W x H x L): 482 mm x 44 mm (1 Rack unit) x 184 mm.
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SIGNAL FLOW
MIC/LINE INPUT
LINE OUTPUT
PAD
LOZ
PHASE
D.I.
INPUT AMP
EQUALIZER
HIGH PASS !
FILTER
OUTPUT AMP

TROUBLE SHOOTING
PROBLEMS
SOLUTIONS
There doesn´t appear to be any signal at all arriving at the
back XLR.
Make sure the GAIN knob is not in the ´Off´ position.
There still doesn´t appear to be any signal at all arriving at
the back XLR.
Check to see if a jack cable has been left plugged into the
front panel D.I.
Condenser microphones don´t seem to work with HA-81A
EQ.
Make sure the red +48 V button is pressed in to activate
the phantom power sent to the microphone.
There doesn´t seem to be any output at all from the unit.
Check to see if the OUTPUT knob is fully turned down as
this will attenuate the signal completely.
Sending a signal to the unit from a DAW overloads it
terrible.
It is necessary to be in the LINE GAIN section when
sending it a line level source.And use the XLR LINE Input
as it expects a signal with a very different impedance and
level.
The Equalizer doesn´t seem to be working.
Make sure you have pushed the EQL button to activate it.
My mid band boost seem to be too sharp.
Check to see if you have the ´HI Q´ button pushed.
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* For any further doubts or questions please get in contact with us at: [email protected]!

LIMITED 2 YEAR WARRANTY
Heritage Audio HA-81A EQ is warranted by Heritage Audio SL to be free from defects in materials and workmanship for
the period of 2 years to the original purchaser. In the event of such defects, the product will be repaired without charge
or, at our option, replaced with a new one if delivered to Heritage Audio prepaid, together with a copy of the sales slip or
other proof of purchase date. The warranty excludes problems due to normal wear, abuse, shipping damage or failure
to use the product in accordance with the specifications.
Heritage Audio shall not be liable for damages based upon inconvenience, loss of use of the product, loss of time,
interrupted operation or commercial loss or any other damages, whether incidental, consequential or otherwise.
This warranty is not transferable.
Heritage Audio and the Heritage Audio “H” logos are registered Trademarks owned and/or licensed by Heritage Audio.
REGISTRATION
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Please visit our website:
WARRANTY STATEMENT
https://heritageaudio.com/registration/

RECALL SHEETS
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Date: Instrument: Notes:
Switch ON
Switch OFF
Session / Title: Track: Connected Equipment: !
Date: Instrument: Notes:
Switch ON
Switch OFF

www.heritageaudio.com
HERITAGE AUDIO. C/ Alfonso Gómez, 38, 3C. 28037 Madrid – Spain. Tel: [phone]
[email protected]