Heritage Audio SYMPH EQ User manual

USER MANUAL
January/2023+Rev.+1.0.+
STEREO ASYMPTOTIC EQUALIZER
RACKMOUNT

2
INTRODUCTION
CONTENTS
DESCRIPTION
FREQUENCY CURVES
GETTING STARTED
HIGH-PASS FILTER CONFIGURATION
APPLICATIONS!
SPECIFICATIONS!
SIGNAL FLOW!
TROUBLE SHOOTING
WARRANTY STATEMENT
REGISTRATION
RECALL SHEETS
2
2
3
5
8
9
10
13
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14
15
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TABLE OF CONTENTS
Thank you for choosing the SYMPH 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
© 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.
SYMPH EQ
AC POWER CORD EU & US
POWER SUPPLY HA-PSU03

DESCRIPTION
The Baxandall EQ has been around for over 70 years now. With the SYMPH Stereo Asymptotic Equalizer, Heritage Audio
has decided to release a version ready to take your mixes to a new level."As usual, with the team at Heritage Audio, simply
precisely recreating its curves and responses wouldn´t be enough… It would also need an improvement…or two.
Heritage Audio has successfully replaced the Baxandall topology with a functional equivalent, a much more musical one.
The SYMPH EQ, takes its name from the shape obtained by its shelf curves; where the boost or cut amplitude grows up
until the asymptotic value is reached, keeping the ultra highs and sub lows always controlled. Its sound can be described
as tight, sweet, natural & pure, and its use of parallel equalizing to obtain the desired response curves ensures it has
exceptionally low phase deviation and undesired artifacts.
Although the interface is deceivingly clear and simple, the results can be stunning. Tiny adjustments can produce huge
changes in clarity, focus, depth and overall impact. Using a combination of the different features available you can also
drastically change the way your music sounds and feels.
"
A clever circuit layout allows for a maximum boost/cut of 10.5 dB in 0.5 dB steps. The main rotary switch sets 1dB steps
whilst the 0.5 button adds half a dB to the main reading so you´ll be able to achieve exactly what you´re after. The
convenient CUT button turns the boost amount into cut to determine problematic frequencies and quickly eliminate them.
A generous six strategically selected frequency choices per band are available: 8, 10, 12, 15, 20 and 24 kHz on the high
shelf and 470, 360, 220, 110, 60 and 20 Hz on the low shelf.
In order to keep the sub-low and ultra-high frequency content well under control, additional high-quality high-pass and low-
pass filters have been added on dual concentric rotary switches, at 12 dB/octave (2 Pole). There are 5 frequency choices
plus OFF available on each filter. Frequencies available are: 10, 12, 18, 22 and 30 kHz on the low-pass and 160, 82, 47,
20 and 15 Hz on the high-pass filter. What´s more, the response of the Side high-pass filter has been made elliptical, just
as it is in the vintage disk cutters for a precise frequency response.
These filters can be critical on your main stereo bus, especially when you´re doing some healthy increases to the high and/
or low shelf as sub low frequencies are not heard but will eat up your headroom and while ultra-high frequencies do not eat
up your headroom that much, they will make your converters work unnecessarily, especially at the higher resolution
sampling frequencies. Get rid of the information that you do not need in the analog domain… your converters will love it. +
3

Most importantly, here is where the SYMPH EQ really shines, it has built in Mid Side (M/S) capabilities. Nothing comes
close to M/S equalizing a mix as it allows the user to process the center and the sides independently. The benefits of such
processing are hard to believe. You can brighten your mix without making your vocals sound harsh, or even tighten the
stereo-image’s bass content without making your bass or kick sound weak! These are just a few examples of the SYMPH
EQ M/S power available to you…but there are tons more!"Now, although mainly used in Mixing and Mastering situations
obviously, the SYMPH EQ´s M/S mode can also be a fantastic tool for individual tracks providing lots of control and
creativity. When in M/S mode, left set of controls will process the Mid channel, while right side will process the Side
channel. Once you´ve tried Mid/Side processing you´ll wonder how you´ve gone so long without it.
"
Keeping in tradition with the majority of the gear produced at Heritage Audio, the stereo inputs and outputs are transformer
coupled and fully balanced to assure a thick, solid, noise-free signal."Once again, exclusive Carnhill transformers from their
St. Ives and Oxford factories have been used to provide the utmost quality. Combined with a 73-style Class-A output stage
you´ll even notice an improvement to the signals with the equalizers bypassed. Simply passing audio through the unit with
no processing will instantly give you a more professional tone thanks to those special transformers and that exquisite
output stage. The SYMPH EQ has been designed with stepped controls for easy recall and exact settings between stereo
channels.
Heritage Audio is also very proud to announce that it is fully manufactured in the EU.
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HIGH PASS FILTER & LOW PASS FILTER
RESPONSE CURVES
5
FREQUENCY CURVES

HIGH SHELF & LOW SHELF
CURVE EXAMPLES
6

7

GETTING STARTED
8
FRONT
REAR
1
2
3
POWER INPUT
To Be Connected to the external Power Supply
(HA-PSU03)
LINE OUTPUTS
Male XLR Connectors
LINE INPUTS
Female XLR Connectors
1
2
3
4
5
HI PASS FILTER SWITCH
-12 dB/octave @ 15, 22, 47,
82, 160 Hz & OFF
LOW PASS FILTER SWITCH
-12 dB/octave @ 10, 12, 18,
22, 30 kHz & OFF
HI FREQUENCY SELECTOR
SWITCH
8, 10, 12, 15, 20, 24 kHz
+ 0.5 dB SWITCH
Adds 0.5 dB to whatever the
selected amount is
HI FREQUENCY
BOOST/CUT AMOUNT
SWITCH
0-10 dB in 1 dB increments
1
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
2
3
4
5
6
7
8
9
10
11
12
13
14
6
7
8
9
10
LOW FREQUENCY
SELECTOR SWITCH
20, 60, 110, 220, 360, 470 Hz
+ 0.5 dB SWITCH
Adds 0.5 dB to whatever the
selected amount is
LOW FREQUENCY
BOOST/CUT AMOUNT
SWITCH
0-10 dB in 1 dB increments
POWER ON SWITCH
Turns unit on
M/S MODE SWITCH
Activates Mid Side mode
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12
13
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CUT MODE SWITCH
Reverses from Boost mode to
Cut mode
CUT MODE SWITCH
Reverses from Boost mode to
Cut mode
BYPASS L SWITCH
Bypasses the Left Channel
BYPASS R SWITCH
Bypasses the Right Channel
1
2
3

HIGH-PASS FILTER CONFIGURATION
9
In order to comply with the old disk cutter #s practice, the high-pass filter has the ability to automatically turn into elliptical
response when in M/S mode. This way, the Mid HPF stays at 12 dB/oct while the Side HPF switches to 6 dB/octave. This
provides the most natural way of “monoing” the bass content as was intended in the vinyl mastering. However, if you prefer
to keep the response of the Side HPF at the steeper 12 dB/octave, this can be configured with a jumper inside the unit as
seen in the pictures below. All units leave the factory with the pre-configured “Elliptical” option. +
As is straight from Heritage Audio, -6 dB/oct HPF…
Modified by moving jumper for -12 dB/oct HPF.
-

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APPLICATIONS
TRACK INSERT
STEREO
MONITOR
SPEAKERS
THUNDERBOLT
COMPUTER
OUPUTS DAW 1 & 2
INPUT CH 1
SYMPH EQ
INPUT CH 2
SYMPH EQ
INPUT DAW CH 2
INPUT DAW CH 1
OUTPUT CH 2
SYMPH EQ
OUTPUT CH 1
SYMPH EQ
BP-L
BP-R
M/S
ON
TRACK INSERT
MID/SIDE
MONITOR
SPEAKERS
THUNDERBOLT
COMPUTER
OUPUTS DAW 1 & 2
INPUT CH 1
SYMPH EQ
INPUT CH 2
SYMPH EQ
INPUT DAW CH 2
INPUT DAW CH 1
OUTPUT CH 2
SYMPH EQ
OUTPUT CH 1
SYMPH EQ
BP-L
BP-R
M/S
ON
Push the M/S button to enter
into the Mid/Side mode.

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MIX BUSS
STEREO
MONITOR
SPEAKERS
THUNDERBOLT
COMPUTER
AUDIO
INTERFACE
SUCCESSOR
LEFT & RIGHT
LINE OUTPUTS
LEFT & RIGHT
LINE INPUTS
PROCESSED MIX
STEREO MIX DAW
LEFT & RIGHT
LINE OUTPUTS
HA-609A
LEFT & RIGHT
LINE INPUTS
ON
COMPRESSOR
LIMITER
HA-609 COMPRESSOR
LEFT & RIGHT
LINE OUTPUTS
SYMPH EQ
LEFT & RIGHT
LINE INPUTS
SYMPH EQ
LEFT & RIGHT
LINE OUTPUTS
SUCCESSOR
LEFT & RIGHT
LINE INPUTS
COMPRESSOR

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MASTERING
MID/SIDE
MONITOR
SPEAKERS
THUNDERBOLT
COMPUTER
AUDIO
INTERFACE
SUCCESSOR
LEFT & RIGHT
LINE OUTPUTS
LEFT & RIGHT
LINE INPUTS
MASTERED MIX
STEREO MIX DAW
LEFT & RIGHT
LINE OUTPUTS
MOTORCITY EQs
LEFT & RIGHT
LINE OUTPUTS
MOTORCITY EQs
LEFT & RIGHT
LINE INPUTS
ON
EQUALIZERS
HA-609 COMPRESSOR
LEFT & RIGHT
LINE INPUTS
HA-609 COMPRESSOR
LEFT & RIGHT
LINE OUTPUTS
SYMPH EQ
LEFT & RIGHT
LINE INPUTS
SYMPH EQ
LEFT & RIGHT
LINE OUTPUTS
SUCCESSOR
LEFT & RIGHT
LINE INPUTS
EQUALIZERS
COMPRESSOR
LIMITER
M/S
Push the M/S button to enter
into the Mid/Side mode.

SPECIFICATIONS
•Maximum input level: Over + 22 dBu.
•Maximum output level: Over + 26.5 dBu into 600 Ω.
•Self-noise: Less than -89 dBu @ EQ Flat.
•THD+N (50 Hz - 20 kHz: Less than 0.07% at +20 dBu.
•Frequency response: ± 0.5 dB, 15 Hz - 30 kHz.
•Input impedance: 10 KΩ, transformer balanced and floating.
•Output impedance: Less than 75 Ω, transformer balanced and floating, Class A driven.
• Dimensions SYMPH EQ (W x H x L): 482 mm x 44 mm (1 Rack unit) x 184 mm.
•Weight: 3.705 Kg.
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SIGNAL FLOW

TROUBLE SHOOTING
PROBLEMS
SOLUTIONS
There doesn´t seem to be any change in the audio
happening.
Make sure the BYPASS buttons have not been left on.
How is the Mid/Side mode activated?
Simply by pushing the M/S button in the middle section of
the SYMPH EQ.
I only want to apply 0.5 dB of increase."How is that
possible?
Just leave the GAIN pot for that frequency at 0 dB and
push the +0.5 dB button.
After applying a healthy amount of Low boost I have too
much Sub now.
This is where those nice High Pass Filters are really
helpful."
Now that I’ve increased a few dBs at 24 kHz, the sound
has the right clarity but is a bit too strident.
Once again, use a filter. In this case a Low Pass Filter at
30 kHz should help out. But do try others as sometimes
you’d be pleasantly surprised at the results.
I´m trying to adjust only the MID channel but it doesn’t
seem to be responding at all.
Remember, in M/S (Mid/Side) mode you must not only
have the button pushed but also remember that the LEFT
channel corresponds to the MID and the RIGHT channel
corresponds to the SIDE signal.
It seems like I can only BOOST signals when what I want
to do is CUT them.
To change the action from boosting to cutting it is
necessary to push the CUT button for that channel and
frequency band.
Exactly how extreme are the Low and High Pass Filters?
The Low and High Pass Filters are 12 dB/Octave (2-Pole).
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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 SYMPH 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.
REGISTRATION
15
Please visit our website:
WARRANTY STATEMENT
https://heritageaudio.com/registration/

RECALL SHEETS
16
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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]