Heritage Audio 6673 80 Series Microphone Preamplifier-EQ Module User Manual

: June 9, 2024
: Heritage Audio

Table of Contents

INTRODUCTION
CONTENTS
DESCRIPTION
- A great 80 Series tool for the ultimate control
GETTING STARTED
APPLICATIONS
SPECIFICATIONS
SIGNAL FLOW
TROUBLE SHOOTING
WARRANTY STATEMENT
- LIMITED 2 YEAR WARRANTY
REGISTRATION
RECALL SHEETS
Customer Support
References
Read User Manual Online (PDF format)
Download This Manual (PDF format)

Heritage Audio 6673 80 Series Microphone Preamplifier-EQ Module

INTRODUCTION

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

© 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.

DESCRIPTION

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

1	2	3	4	5

APPLICATIONS

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)

SIGNAL FLOW

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: support@heritageaudio.com

WARRANTY STATEMENT

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.