Heritage Audio 6673 User manual

USER MANUAL
MODULE MIC PREAMP/EQ
80 Series
6673
January/2023+Rev.+2.0+

2
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 6673 Module. 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
© 2023 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.
6673 MODULE

DESCRIPTION
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A great 80 Series tool for the ultimate control
Leverage your 80 Series´s investment with the Heritage Audio 6673.!
The 6673 module is a Heritage Audio unique design, which has been engineered to fill input module slots in the
restoration process of vintage 80 Series sound mixing consoles."It is also compatible with the Heritage Audio FRAME 8
and RACK 2 powered enclosures, and with any other rack, console or enclosure that follows the same mechanical and
electrical protocol.
The 6673 offers what the vintage modules do plus much, much more
The 6673 has a Class A Mic preamp with 80 dB of gain to make sure you´re never lacking for more."This gives you
more than enough even for demanding ribbon mics and older dynamic mics, which are often low output."With the 6673
your mic collection has never sounded better."
There is also a Class A line-level amplifier with 10 dB of additional gain as well as -20 dB for when you need to reduce a
very high signal coming into the unit before EQing it."Both the Mic preamp and the Line amplifier have their own
separate exclusive Carnhill transformers to guarantee solid, professional results."
""""""" """"""""""""""""""""""""""""""""""""""""""""
The 6673 is a 73-sized module, adding the 1066 mid bands to the 73 classic design, creating an equalizer that is really
hard to beat. It features a Baxandall type high shelf band, but with the addition of a high frequency selector switch
offering 3 different frequencies instead of the fixed one at 12 kHz. There are also two Mid peak bands (Hi & Low) with
10 selectable frequencies to choose from each in addition to the OFF position that removes the filter from the signal
path."Then you have a Low Shelf band, also of the Baxandall type, with 4 selectable frequencies available for some
incredible low end shaping."The result is a 4-band tone monster that combines the best features of the vintage modules
in a smart and tasteful way, at a price lower than most current offerings."And not to be overlooked, the 6673 has a
Class A High Pass Filter with 3 frequencies to choose from to make you can clean up the very low end allowing more
room to achieve the sound you want."
Vintage connoisseurs and plug-in users already know how cool the 1066 mid bands are for sculpting sounds in a
musical way. This level of flexibility has never been present in a 73 style module and will certainly make finding that
elusive sound much easier.
Using the right components is necessary to achieve
desired sound
Special care has been taken in sourcing the correct components that
not only ensure that performance will be as close to a 1970´s unit as
possible, but also gives your top-class studio the look and feel it
deserves to help enhance the overall experience.
Custom polystyrene and film capacitors have been developed to
closely match the Siemens styroflex and Mullard Mustard types of the
late 60s and early 70s."This attention to detail is reflected in the unit´s
performance and is appreciated by the end user.
Carnhill input transformers are hand wound at its Oxford factory
exclusively for Heritage Audio, enclosed in vintage correct green metal
cases for the ultimate in detail nailing. The vintage character is indeed
guaranteed and you won´t find them in any other brand´s products.
A solid, thick output is guaranteed with the use of another Carnhill
transformer on the fully balanced output. The RACK 2 and FRAME 8
contain output pots to control the exact level required.
The Heritage Audio 6673 is entirely
handmade and hand wired by our most
experienced technicians in our facilities in
Madrid, Spain, employing the same wiring
and soldering techniques of the 70s. All its
circuitry is conveniently held on 5 plug-in
cards.

GETTING STARTED
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FRONT
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3
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7
2
4
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8
13
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1
REAR
80 SERIES EDGE CONNECTOR PIN OUT
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2
3
4
5
6
7
8
9
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15
16
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18
0 V
To Pin V
Hi
Lo
Mic I/P
-20 dBu
Hi
Lo
Line I/P
0V
To Pin V
LINK
Unbalanced O/P
Hi
Lo
BAL O/P
To Pin V
+24 V at 106 mA
0 dBu
0 dBu
-3 dBu
Technical!
Earth Link
1
MIC INPUT IMPEDANCE
1200 Ωor 300 Ωwhen
pressed
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7
8
9
10
LOW MID BOOST/CUT
+/- 15 dB at Selected
Frequency
LOW MID PEAK FREQUENCY
Low Band Frequency Selection
BASS SHELF BOOST/CUT
+/- 15 dB at Selected
Frequency
BASS SHELF FREQUENCY
220, 110, 60 and 35 Hz
HIGH PASS FILTER
50 Hz
1
2
3
4
5
INPUT GAIN SWITCH
5 dB Steps From 20 to 80 dB in
MIC mode and -20 dB to 10 dB
in LINE mode
HIGH SHELF BOOST/CUT
+/- 15 dB at Selected
Frequency
HIGH SHELF FREQUENCY
10, 12 and 16 kHz Options
HIGH MID BOOST/CUT
+/- 15 dB at Selected
Frequency
HiGH MID PEAK
FREQUENCY
Mid Band Frequency Selection
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12
13
14
15
HIGH PASS FILTER
80 Hz
HIGH PASS FILTER
Pressing both buttons gives a
300 Hz cut
EQL
Turns Equalizer On
PHASE
Flips phase 180º
FASTENING SCREW
To secure 80 Series module in
enclosure
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MIC
APPLICATIONS
D.I.
LINE
CONDENSER MIC - L
LINE INPUTS - AUDIO INTERFACE
USB - COMPUTER
MIC INPUT 2
MIC INPUT 1
OUTPUT - 2
GUITAR FX PEDAL
5
LINE OUTPUTS - KEYBOARD
CONDENSER MIC - R
OUTPUT -1
LINE INPUTS - AUDIO INTERFACE
USB - COMPUTER
D.I. INPUT 2
D.I. INPUT 1
OUTPUT - 1
LINE INPUTS - AUDIO INTERFACE
USB - COMPUTER
OUTPUT -2
LINE INPUT -2
LINE INPUT -1
ACTIVATE +48V FOR CONDENSER
Rack 2!
Not included
OUTPUT - 2
OUTPUT -1
Rack 2!
Not included
Rack 2!
Not included
You need to be in the
LINE GAIN section to
use the LINE Inputs

SPECIFICATIONS
•Class A mic preamp with 80 dB of gain, plus a sweet-sounding 4-band EQ.
•Class A line-level amplifier with 10 dB of gain.
•Equalizer’s mid-bands cover nearly the entire audible frequency range.
•Low and high shelving EQs with Baxandall curves for smooth, natural-sounding response.
•High-pass filter, switchable between 50 Hz, 80 Hz, and 300 Hz.
•+48 V phantom power is supplied by your 80 Series chassis.
•Maximum output: Greater than +26 dBu into 600 Ω.
•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.
•Noise: Less than -100 dBu.
•Power consumption: Less than 110 mA @ 24V DC.
•Dimensions (W x H x L): 45 mm x 224 mm x 304 mm. (Standard Series 80 Module)
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SIGNAL FLOW
MIC INPUT
LINE OUTPUT
LOZ
PHASE
D.I.
INPUT AMP
HPF
OUTPUT AMP
LINE INPUT
D.I. Input accessible on the front panel of the RACK 2.
EQ

TROUBLE SHOOTING
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PROBLEMS
SOLUTIONS
I can´t seem to get any signal out of the 6673.
Check to make sure you have not left the GAIN knob in an
´OFF´ position.
I still can´t seem to get any signal out of the 6673.
Check to make sure you have not left the OUTPUT knob
turned all the way down on your rack enclosure.
Is it possible to use a bass or electric guitar with the 6673.
It certainly is. There are two convenient DI inputs on the
RACK 2 enclosure and with the FRAME 8 or any other
setups you could simply use a DI box ahead of the 6673.
How do I activate the 300 Hz low cut filter?
You must push both of the buttons, the 50 Hz and 80 Hz
buttons to access the 300 Hz cut.
I can´t figure out how to change the impedance.
There is a switch on the backside of the module. It does
require pulling the module out of the RACK 2 or SESSION
8 to access the switch. It switches between 1200 ohm and
300 Ω.
Can I simply use the Hi Shelf on the EQ without using the
other bands?
Yes, of course."You simply leave the other bands in the
´OFF´ position and they will not be in the signal path.
* For any further doubts or questions please get in contact with us at: [email protected]!

LIMITED 2 YEAR WARRANTY
Heritage Audio 6673 Module 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
9
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www.heritageaudio.com
HERITAGE AUDIO. C/ Alfonso Gómez, 38, 3C. 28037 Madrid – Spain. Tel: [phone]
[email protected]