Sonodyne SSP 2025 User manual

SSP 2025
dual channel 31 band graphic equalizer I owners manual
www.sonodyne.com

SSP 2025 page 1
STATUTORY INFORMATION/ PRECAUTIONS
IMPORTANT SAFETY INSTRUCTIONS
1. Read and follow these instructions.
2. Do not use this apparatus near water.
3. Clean with dry cloth only.
4. Do not block any ventilation openings. Install in accordance with the manufacturer’s instructions.
5. Do not install near any heat sources such as radiators, stoves, or other apparatus (including amplifiers)
that produce heat.
6. Do not defeat the safety purpose of the polarized or grounding-type plug. A grounding type plug has two
poles and a third grounding pole. The thick pole is provided for your safety. If the provided plug does not
fit into your outlet, consult an electrician for replacement of the outlet
7. Protect the power cord from being walked on or pinched particularly at plugs, convenience receptacles,
and the point where they exit from the apparatus.
8. The apparatus shall be connected to a MAINS socket outlet with a protective earthing connection.
9. Unplug this apparatus during lightning storms or when unused for long periods of time.
10. Refer all servicing to qualified service personnel. Servicing is required when the apparatus has been
damaged in any way, such as power-supply cord or plug is damaged, liquid has been spilled or objects
have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does not operate
normally, or has been dropped.
The lightning flash with arrowhead symbol within an equilateral triangle is intended to alert
the user to the presence of “un-insulated dangerous voltage” within the product’s enclosure
that may be of sufficient magnitude to constitute a risk of electric shock.
The exclamation point within an equilateral triangle is intended to alert the user to the
presence of important operating and maintenance (servicing) instructions in the literature
accompanying the product.
WARNING:
TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS APPARATUS TO RAIN OR MOISTURE
CONNECTORS
XLR-type connectors are wired as follows (IEC60268 standard): pin 1: ground, pin 2: hot (+), pin 3: cold (-).

Thank you for purchasing the Sonodyne Graphic Equalizer. Please read this manual thoroughly to get the
most out of the product and ensure long-term, trouble-free use. After reading this manual, keep it available
for future reference.
MAIN FEATURES
• Two31-band,1/3-octaveConstantQfrequencybands
• NoiseReduction
• Limiter
• Switchable+-6dband+-15dbgain
• 18db/octave40HzBessellow-cutlter
• Groundlift
• -12dBto+12dBinputgainrange
• XLR,TRSandBarrierstripconnectors
• Power-offhard-wirerelaybypasswith2secpowerupdelay
IN THE BOX
Verify that the package contains the following:
• Equalizerunit
• ACpowercord
• OperatingManual
• Fourrackmountscrewsandwashers
SSP 2025 page 2
MAIN FEATURES/ IN THE BOX

FRONT PANEL
SSP 2025 page 3
1. NR (Noise Reduction) SWITCH AND LED: The switch engages the Noise Reduction circuit
 withintheEQ.TheNoiseReductionyellowLEDlightsupwhentheNoiseReductionswitchispressed
2. EQ BYPASS SWITCH and LED: Engaging this switch removes the graphic equalizer section
 fromthesignalpath.TheBYPASSswitchdoesnot,however,affecttheINPUTGAIN,orLOWCUT
 lters.TheEQBypassLEDlightsupwhentheswitchispressed
3. INPUT GAIN CONTROL: This control sets the signal level input to the equalizer. It varies the
 signallevelfrom-12dBto+12dB.ItseffectcanbeviewedontheOUTPUTLEVELBARGRAPH
4. LOW CUT SWITCH:TheLOW-CUTswitchwhenpressedinsertsan18dB/octave40HzBessel
low-cut filter into the signal path
5. LIMITER THRESHOLD CONTROL: This control engages the limiter. It sets the threshold
 levelatwhichgainreductionbeginstooccur.Thecontrolrangeis0dButo“OFF”(+24dBu).Whenthe
threshold control is set to “OFF”, the limiter is disabled
6. BOOST/CUT RANGE SELECTION SWITCH and LEDS: This switch selects the two
 boost/cutrangesoftheequalizer,either±6dBor±15dB.TheredLEDlightswhenthe±15dBrangeis
 selected,andtheyellowLEDlightswhenthe±6dBrangeisselected
1 2 43 5 6
7 8 9 10

FRONT PANEL
SSP 2025 page 4
7. CLIP LED:ThisLEDlightswheneveranyinternalsignallevelreaches3dBbelowclipping
8. OUTPUT BAR GRAPH LEVEL: These four LEDs indicate output level of the equalizer. The red
 LEDis3dBbelowclippingandismarkedas+18dBu.Itmonitorsthelevelattheoutputofthe
equalizer after all other processing, including the limiter
9. GAIN REDUCTION METER: These four LEDs indicate the amount of gain reduction introduced
by the setting of the LIMITER THRESHOLD control
10. FREQUENCY BAND SLIDER CONTROLS: Each one of these slider potentiometers will
 boostorcutatitsrespectivefrequencyby±6dBor±15dB,dependinguponthepositionofthe
 BOOST/CUTRANGEswitch.Whenalltheslidersareinthecenterdetentpositionthefrequency
 responseoftheequalizerisat.Thefrequencybandcentersaremarkedat1/3rdoctaveintervalson
ISO standard spacing

SSP 2025 page 5
The Equalizer has balanced inputs and outputs that can be used with any balanced or unbalanced line-
level device. For more specific information about cabling possibilities, please refer to the section entitled
INSTALLATION CONSIDERATIONS.
• Turn off all equipment before making connections.
• Mount equalizer in a standard-width rack.
 InstalltheEQsinarackwiththerackscrewsprovided.Itcanbemountedaboveorbelowanything
that does not generate excessive heat. Ambient temperatures should not exceed 45°C when
equipment is in use. Although the unit’s chassis is shielded against radio frequency and
electromagnetic interference, extremely high fields of RF and EMI should be avoided.
• Make audio connections via XLR, barrier strip, or 1/4” TRS jacks (according to
application needs)
All three types of connectors for the inputs and outputs can be used for balanced or unbalanced
connections.
The use of more than one connector at a time for the inputs could unbalance balanced lines, cause
phase cancellation, short a conductor to ground, or cause damage to other equipment connected to
the equalizer. More than one output may be used simultaneously as long as the combined parallel load
is greater than 600Ω.
• Select the operating range with the BOOST/CUT RANGE SELECTION switch
 NOTE:Besuretoreduceaudiolevelsatthepoweramplierswhenchangingthesettingofthisswitch
as it may generate an audible transient.
• Apply power to the equalizer
Connect the AC power cord to the AC power receptacle on the back of the equalizer. Route the AC
power cord to a convenient power outlet away from audio lines. The unit may be turned on and off
from the rear panel power switch or a master equipment power switch. Since the Equalizers consume
a relatively small amount of power, the units may be left on continuously.
CONNECTING THE EQ TO YOUR SYSTEM

SSP 2025 page 6
REAR PANEL
1. IEC AC INLET: Connect the socket end of the mains cable provided with this unit to this socket and
the plug end to a 230V AC outlet. Ensure that the ground pin of the AC outlet has a firm connection
with the earth of the premises. This is both in the interests of your own safety as well as to eliminate
ground related hum and buzz problems
2. POWER SWITCH: Switches the power on and off. Always make audio connections with the
power switch in the OFF position
3. OUTPUT CONNECTORS: Three types of output connectors are provided for output
 connections:maleXLRtypeconnectors,1/4”tip-ring-sleevephonejackconnectorsandabarrier
strip
4. CHASSIS GROUND LIFT STRAP: Byremovingthejumperconnectingthetwoscrewson
the barrier strip, the chassis ground is separated from the circuit ground of the equalizer. This is
sometimes necessary to prevent “ground loops” in a sound system. When lifting the ground strap, you
must make a connection from the circuit ground terminal to some other ground point in your audio
system in order for the equalizer to function properly
5. INPUT CONNECTORS: Three types of input connectors are provided for input connections:
 femalelockingXLRtypeconnectors,1/4”tip-ring-sleevephonejackconnectors,andabarrierstrip.
 Themaximuminputlevelthattheequalizercanacceptwithoutclippingis+22dBu(ref:0.775Vrms)
1 2 43 5

INSTALLATION CONSIDERATIONS
INSTALLATION CONSIDERATIONS
HOOKUPS AND CABLING:TheEqualiserisdesignedfornominal+4dBulevels.Theequalizercan
be used with either balanced or unbalanced sources, and the outputs can be used with either balanced or
unbalanced loads, provided the proper cabling is used.
INPUT CABLE CONFIGURATIONS: The equalizer has an input impedance of 40kΩ balanced and
20kΩ unbalanced. This makes the Equalizer’s audio inputs suitable for use with virtually any low source
impedance (under 2kΩ).
OUTPUT CABLE CONFIGURATIONS: The equalizer’s output is capable of driving a 600Ω load to
+18dBu.Formaximumhumrejectionwithabalancedsource,avoidcommongroundingattheequalizer’s
inputs and outputs. Most balanced (3-conductor) cables have the shield connected at both ends. This can
result in ground loops which cause hum. If hum persists try disconnecting the shield on one or more of the
cables in the system, preferably at the input of a device, not at the output.
SSP 2025 page 7
WIRING CONNECTIONS WITH GROUND
WITHOUT JUMPER IN PLACE WITH JUMPER IN PLACE
CIRCUIT
GROUND
OUTPUT
CABLE
OUTPUT
CABLE
OPTIONAL OPTIONAL
INPUT
CABLE
INPUT
CABLE
TOSYSTEM
GROUND
CIRCUIT
GROUND
CHASSIS
GROUND
CHASSIS
GROUND JUMPER

NO SOUND If there appears to be no power:
•CheckthateitherthestereoormonoLEDonthefrontpanel
of the crossover is lit.
•Checkthatthepowercordisseatedproperlyintheback
panel of the crossover and that it is plugged into an active
AC power source.
IF THERE APPEARS TO BE
POWER, BUT NO AUDIBLE
SIGNAL
•Conrmthatactiveaudiolinesareconnectedtothe
crossover’s inputs and outputs.
•Checkthatboththeinputandoutputgaincontrolsare
advanced sufficiently.
•Checktomakesurethatyouhaveturneduptheampliers’
outputs.
HUM AND/OR BUZZ If you suspect that the hum is caused by a ground loop:
•Systematicallyremoveand/orconnecttheaudiogroundsof
the devices in the signal path
•Remember,forsafetyyoumustmaintainconnectionto
chassis ground. Never lift a safety ground
IF YOU SUSPECT THE HUM IS
NOT CAUSED BY A GROUND
LOOP
•Checktheaudioatanearlierstageintheaudiochain.
•Lowlevelequipmentshouldbemountedawayfrompower
amplifiers to avoid induction of this type of hum.
•Becertainthatallaudiowiringexceptforloudspeakerlines
is well shielded, and that low level wiring is not run parallel
toand/orincloseproximitytoACpowerwiring.
INTERMITTENT AUDIO •Checktheotherequipmentandthewiringtomakecertain
that the signal is not Intermittent earlier in the chain.
•Checktheintegrityofallcablesusingacabletester.
TROUBLESHOOTING
SSP 2025 page 8

INPUTS
CONNECTORS
TYPE
IMPEDANCE
MAX INPUT LEVEL
CMRR
1/4”TRS,femaleXLR(pin2hot),andbarrierterminalstrip
Electronicallybalanced/unbalanced,RFltered
Balanced40kΩ,unbalanced20kΩ
>+21dBubalancedorunbalanced
>40dB,typically>55dBat1kHz
OUTPUTS
CONNECTORS
TYPE
IMPEDANCE
MAX OUTPUT LEVEL
1/4”TRS,maleXLR(pin2hot),andbarrierterminalstrip
Balanced/unbalanced,RFltered
Balanced120Ω,unbalanced60Ω
>+21dBubalanced/unbalancedinto2kΩorgreater
>+18dBmbalanced/unbalanced(into600Ω)
SYSTEM PERFORMANCE
BANDWIDTH
FREQUENCY RESPONSE
NOISE REDUCTION IN
SIGNAL TO NOISE RATIO
DYNAMIC RANGE
NOISE REDUCTION OUT
SIGNAL TO NOISE RATIO
DYNAMIC RANGE
NOISE REDUCTION OUT
SIGNAL TO NOISE RATIO
DYNAMIC RANGE
THD + NOISE
INTERCHANNEL CROSSTALK
NOISE REDUCTION
20Hz~20kHz,+0.5/-1dB
<10Hzto>50kHz,+0.5/-3dB
(±6and±15dBrange):
>100dB,unweighted,ref:+4dBu,22kHzmeasurementbandwidth
>118dB,unweighted
(±6dBrange):
>94dB,unweighted,ref:+4dBu,22kHzmeasurementbandwidth
>112dB,unweighted
(±15dBrange):
>90dB,unweighted,ref:+4dBu,22kHzmeasurementbandwidth
>108dB,unweighted
<0.04%,0.02%typicalat+4dBu,1kHz
<0.5%at1kHzwith15dBgainreduction
<-80dB,20Hzto20kHz(2215/2231)
Upto20dBofdynamicbroadbandnoisereduction
FUNCTION SWITCHES
NR
EQ BYPASS
LOW CUT (recessed)
RANGE (recessed)
Activates Noise Reduction
Bypassesthegraphicequalizersectioninthesignalpath
Activatesthe40Hz18dB/octaveBesselhigh-passlter
Selectseither±6dBor±15dBsliderboost/cutrange
INDICATORS
OUTPUT LEVEL
GAIN REDUCTION
TYPE III NR
EQ BYPASS
CLIP
LOW CUT
±6dB
±15dB
4-LEDbargraph(Green,Green,Yellow,Red)at-10,0,+10,and+18dBu
4-LEDbargraph(allRed)at0,3,6,and10dB
1 LED: yellow
1 LED: red
1 LED: red
1 LED: red
1 LED: yellow
1 LED: red
POWER SUPPLY
OPERATING VOLTAGE
POWER CONSUMPTION
MAINS CONNECTION
230VAC50/60Hz
28W
IEC receptacle
PHYSICAL
DIMENSIONS (HxWxD)
WEIGHT
134 mm x 483 mm x 201 mm
4.8kg
Due to continuous improvements, all specifications are subject to change
SPECIFICATIONS
SSP 2025 page 9

NOTES
SSP 2025 page 10

A product of the Mukherjee Innovation Centre
SonodyneTechnologiesPvt.Ltd,98NBBlockENewAlipore,Kolkata700053,INDIA
Tel: [phone]; E-mail: [email protected]
Please visit us at www.sonodyne.com