Rockford Fosgate 125.2 User manual

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car audio
fanatics
for
punc
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2-Channel Amplifiers
Operation & Installation
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Dear Customer,
Congratulations on your purchase of the world's finest brand of car audio amplifiers.
AtRockfordFosgatewearefanaticsaboutmusicalreproductionatitsbest,andweare
pleasedyouchoseourproduct.Throughyearsofengineeringexpertise,handcraftsman-
ship and critical testing procedures, we have created a wide range of products that
reproduce music with all the clarity and richness you deserve.
For maximum performance we recommend you have your new Rockford Fosgate
product installed by an Authorized Rockford Fosgate Dealer, as we provide specialized
training through Rockford Technical Training Institute (RTTI). Please read your
warranty and retain your receipt and original carton for possible future use.
Greatproductandcompetent installationsareonly apieceofthepuzzle whenitcomes
to your system. Make sure that your installer is using 100% authentic installation
accessories from Connecting Punch in your installation. Connecting Punch has
everything from RCA cables and speaker wire to Power line and battery connectors.
Insist on it! After all, your new system deserves nothing but the best.
To add the finishing touch to your new Rockford Fosgate image order your Rockford
wearables,which include everything from T-shirts and jackets tohats and sunglasses.
To get a free brochure on Rockford Fosgate products and Rockford accessories, in the
U.S.call602-967-3565orFAX602-967-8132.Forallothercountries,call+001-602-
967-3565 or FAX [phone].
If, after reading your manual, you still have questions regarding this product,
we recommend that you see your Rockford Fosgate dealer. If you need further
assistance, you can call us direct at 1-800-669-9899. Be sure to have your serial
number, model number and date of purchase available when you call.
PRACTICE SAFE SOUND™
CONTINUOUS EXPOSURE TO SOUND PRESSURE LEVELS OVER 100dB
MAY CAUSE PERMANENT HEARING LOSS.HIGH POWERED AUTOSOUND
SYSTEMS MAY PRODUCE SOUND PRESSURE LEVELS WELL OVER
130dB. USE COMMON SENSE AND PRACTICE SAFE SOUND.
The serial number can be found on the outside of the box. Please record it in
the space provided below as your permanent record. This will serve as
verificationofyourfactorywarrantyandmaybecomeusefulinrecoveringyour
amplifier if it is ever stolen.
Serial Number: ________________________________
Model Number:________________________________

T ABLE OF C ONTENTS
Introduction................................................................................................1
Punch Amplifier Accessory Pack ................................................................... 1
Technical Design Features............................................................................2
Design Features .......................................................................................... 5
Installation Considerations ...........................................................................7
Mounting Location ...................................................................................... 8
Battery and Charging ..................................................................................9
Wiring the System....................................................................................... 9
Using Passive Crossovers........................................................................... 12
Table of Component Values........................................................................ 13
Using the XCard........................................................................................ 14
Resistor Chart ........................................................................................... 15
Installation ...............................................................................................16
System Diagrams...................................................................................... 20
Rockford Fosgate Accessories ..................................................................... 24
Troubleshooting........................................................................................ 26
Dynamic Power Measurements................................................................... 29
Specifications ........................................................................................... 31
Warranty Information ................................................................................ 33
International Information............................................................................34
Sections marked
ADVANCED OPERATION
include in-depth
technical information
Sections marked
TROUBLESHOOTING
include recommendations for
curing installation problems
Sections marked
INSTALLATION
include “slam dunk”
wiring connections
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Welcometo Rockford Fosgate! This manual is designed to provideinformation
for the owner, salesperson and installer. For those of you who want quick
information on how to install this product, please turn to the Installation
Section of this manual or refer to the icons listed below. Other information can
be located by using the Table of Contents. We, at Rockford Fosgate, have
workedveryhardtomakesurealltheinformationinthismanualiscurrent.But,
asweareconstantlyfindingnewwaystoimproveourproduct,thisinformation
is subject to change without notice.
GETTING STARTED
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I NTRODUCTION
Rockford engineers designed the Punch 55.2, 75.2, 125.2and 225.2
amplifierstowithstandtheruggedautomotiveenvironmentwhiledelivering
superiorsoundqualityinaflexible,reliable,andefficientpackage.TRANS•ANA
is a low voltage circuit in the preamp stage of all Punch .2amplifiers that
lets the music sound crystal clear and very real, even when played at high
volumelevels.ThisismatchedwithTOPAZ,auniquegroundingcircuitused
to eliminate noise problems associated with car audio systems and their
installation. Flexibility is accomplished with the use of a built-in XCard.
Reliability is all but guaranteed with the use of a protection circuit called
NOMAD, while MOSFET and DSM (Discrete Surface Mount) technology
improveamplifierefficiency.Theresultof thesecomponentsgive thePunch
amplifier awesome sound quality in a “Bullet Proof” package. An explana-
tion of these technologies, most of which are exclusively designed and
patented by Rockford, are described in the Technical Design Features.
– 1 –
P UNCH A MPLIFIER A CCESSORY P ACK
The accessory pack shipped with the Punch 2-channel amplifiers includes
the mounting hardware necessary to secure the amp to the vehicle and to
attach the end caps to the amplifier.
Installation & Operation Manual
Punch Verification Certificate
(4) Amplifier mounting screws (#8 x 3/4" Phillips)
(6) Speaker & power connector screws (3/32" Allen)
(4) End cap mounting screws (9/64" Allen)
(1) Allen Wrench 9/64"
(1) Allen Wrench 3/32"
(1) ATC Inline Fuseholder (Punch 55.2, 75.2, 125.2)
(1) AGU Inline Fuseholder (Punch 225.2)
(1) ATC 20 Amp Fuse (Punch 55.2)
(1) ATC 30 Amp Fuse (Punch 75.2)
(1) ATC 40 Amp Fuse (Punch 125.2)
(1) AGU 50 Amp Fuse (Punch 225.2)

T ECHNICAL D ESIGN F EATURES
– 2 –
◆TRANS•ANA
(TRANSconductance Active Nodal Amplifier)
The TRANS•ANA (TRANSconductance Active Nodal Amplifier) is a circuit
thatallows the audio signal to passthroughtheamplifier at low voltage. The
signalisdirectly level-shiftedtothefixedhigh voltagerailsviaapair ofdriver
transistors. Signal linearity is assured by an active node formed by the drive
transistors at ultrasonic frequencies. This allows amplifier performance
similar to trans• nova which is highly stable and linear while utilizing the
advantages of a non-floating power supply.
THE RESULT: An extended frequency bandwidth accurately supplied to the
output stages of the amplifier.
◆TOPAZ (Tracking Operation Pre-Amplifier Zone)
The TOPAZ (Tracking Operation Pre-Amplifier Zone) circuitry solves ground
loopnoiseproblemscommontoautomotiveamplifierdesign.Thisinnovative
newdevelopmentallowsvastlyimprovedisolationoftheinputsignalgrounds
from the power supply ground of the amplifier. This is accomplished by
allowing the source unit to control the potential “environment” of the entire
input structure or “zone” of the amplifier. This process improves the noise
rejection of the amplifier by 30-40dB – an astounding 30-100 times better
than amplifiers without TOPAZ.
THE RESULT: Eliminationof troublesome ground loopnoisebetweensource
and amplifier.
◆MEHSA (Maximum Efficiency Heat Sink Application)
The MEHSA (Maximum Efficiency Heat-Sink Application) is a proprietary
process that yields up to 5 times better heat transfer than traditional FET
mounting techniques using the exact same components. A multi-layer
insulatedmetal substrate operatingwithminimal thermalresistancespreads
heat both downward & outward to quickly dissipate heat from each device
across the heat sink. This process combined with our DSM technology and
MOSFET devices allow us to squeeze more watts per cubic inch from every
output device as well as provide consistent thermal stability.
THE RESULT: Optimized power output, enhanced thermal stability, and
maximum component reliability.

◆DSM (Discrete Surface Mount) Technology
The DSM (Discrete Surface Mount) manufacturing process combines the
advantages of both discrete components and integrated circuitry. Rockford
FosgateistheonlyAmericanamplifiermanufacturertohaveinvestedmillions
intothisprocess.DSMcomponentsdifferfromconventionaldiscretecompo-
nents in different ways. They are more compact, more rugged, and they
efficientlydissipate generated heat.Usingthem whereverappropriateallows
the advantages associated with discrete circuitry to be retained while also
providing room for both highly advanced processing features and generous
PC board copper paths where needed. Their short lead-out structures allow
maximum audio performance and highest signal-to-noise ratios to be
obtained in amplifiers of desirable package size without resorting to “ampli-
fier-on-a-chip” shortcuts. These advantages are shown below in Figure 1.
THE RESULT: Fewer connections, improved reliability, shorter signal paths,
superior signal-to-noise ratio and awesome sonic performance.
Figure 1
◆XCard (Internal Crossover)
ThePunchamplifiersutilizeinternalactivecrossovers.Thesecrossovershave
manyperformanceadvantagessuch asusing discretecomponents forexact
frequencyadjustmentswhicharefarsuperiortopotentiometers.Additionally,
the XCard can be configured for high-pass, low-pass and full range
operation. With slight modifications, many crossover frequencies and slope
configurations can be achieved.
THE RESULT: Increased system design flexibility with a precise electronic
crossover without the limitations of conventional potentiometer designs.
– 3 –
Solder Solder
Component
Thru-Hole Surface Mount
PC
Board PC
Board

◆MOSFET Devices
Rockford Fosgate is one of the few manufacturers in the sound community
to utilize MOSFET devices in both the power supply and the output stages .
MOSFET (Metal Oxide Semiconductor Field Effect Transistor) devices offer
severalimportantinherentadvantagesoverthe30yearoldtechnologyofbi-
polar design. These advantages include: thermal stability, switching speed,
ultra low output impedance and wider bandwidth linearity. In addition,
MOSFETsoperateverysimilarly tovacuum tubesin thattheyaremorelinear
thanbi-polartransistors.However,MOSFETscandeliverthemidrangeclarity
without the limitations of transient response and high frequency phase
shifting normally associated with tube operation.
THE RESULT: Operational characteristics similar to vacuum tubes without
the performance limitations of tube design.
◆NOMAD (NOn-Multiplying Advanced Decision)
The Punch amplifiers use an analog computer process to maximize safe
output power under all operating conditions. The innovative NOMAD (NOn-
Multiplying Advanced Decision) system is the most sophisticated version of
thistechniqueeverused,bringingpreviouslyunavailablelevelsofaccuracy,
stability,temperatureimmunityandreliabilitytothiscriticalprocess.NOMAD
makesadvanceddecisionsbasedondevicevoltagesto preciselycontrolthe
awesome levels of current available in the output MOSFETs to safe values –
but only when absolutely needed.
THE RESULT: Extremely fast protection system that always protects the
amplifier and never degrades the sound.
– 4 –
◆Punch EQ
The Punch EQ helps correct for acoustical deficiencies in the listening
environment. Two unique potentiometers that control bass and treble
compensatefortheresponseerrorspresentinmostcarenvironments.Unlike
conventionaltonecontrols,PunchEQcorrectsthespecificproblemsofpoor
low bass response and high frequency rolloff.
THE RESULT: Full range sound without excessive boost in areas where it is
not needed.

D ESIGN F EATURES
1. Cast Aluminum Heatsink – The cast aluminum heatsink of the Punch
amplifier dissipates heat generated by the amplifier's circuitry. The
inherentadvantageof casting provides a 30% improvement of cooling
over conventional extrusion heatsink designs.
2. End Caps – The unique end caps conceal the wiring and input cables,
giving the amplifier a clean “stealth” look.
+R–+L– Bass
Right
Gain
Right
Input
Left
Input
Left
Gain
Treble
Speaker Speaker
3 8 7 7
6 6 83
3. Speaker Terminals – The heavy duty, gold-plated terminal block
connectors (+ and –) will accept wire sizes from 8 AWG to 18 AWG.
These gold-plated connectors are immune to corrosion that can cause
signal deterioration.
4. Power Terminals – The power and ground connectors on the Punch
amplifier are gold-plated and will accommodate up to 8 AWG wire
maximizing the input current capability of the amplifier.
5. REM Terminal – This gold-plated spade terminal is used for the auto
power/remote turn on of the Punch amplifier.
6. RCA Input Jacks – The industry standard RCA jacks provide easy
connections for signal level input. They are gold-plated to resist the
signal degradation caused by corrosion.
49 5
GNDB+
LED
REM
– 5 –

7. Input Sensitivity Controls – The input level controls are preset to
matchtheoutputofmostsourceunits.They canbeadjustedtomatch
output levels from a variety of source units.
8. Punch Equalization Controls – The Punch EQ helps correct for
acoustical deficiencies in the listening environment. The Bass control
allowsanarrowbandadjustmentofupto18dBcenteredat45Hz.The
Treble control is a wide band hinged adjustment with a maximum of
12dB at 20kHz. The Punch EQ can be bypassed by turning the
controls to their minimum or counterclockwise position.
9. LEDPowerIndicator–TheLEDilluminateswhentheunitisturnedon.
10. XCard (Internal Crossover) – This built-in crossover card is
configurable for a multitude of operating frequencies. The orientation
ofthecardinitssocketdeterminesthefunctionofhigh-pass,low-pass,
or full range operation.
– 6 –
HP
LP
HP
LP
FULL
For Bridged Mono Wiring
Connect 4Ωmono woofer + to L+ of amplifier
and mono woofer – to R– of amplifier. Amplifier
will operate mono/stereo simultaneously.
ROCKFORD CORPORATION
MADE IN THE USA
®
®
27.5 Watts RMS continuous power per
channel into 4 Ohms with less than 0.08%
Total Harmonic Distortion from 20-20kHz
AMPLIFIER
Do Not Chassis
Ground Any Speaker.
+–
L+ R–
Low-Pass
Full Range
High-Pass
10

I NSTALLATION C ONSIDERATIONS
Thefollowingis alistoftoolsyou willneedforinstallingthe Punchamplifier:
Allen wrenches 9/64" & 3/32" (included) Voltmeter
Wire strippers Battery post wrench
Electric hand drill w/assorted bits Wire cutters
17' (518.16cm) Red Power Wire Assorted connectors
12' (365.76cm) Remote Turn-On Wire Wire crimpers
1.5' (45.72cm) Black Grounding Wire
– 7 –
Thissectionfocusesonsomeofthevehicleconsiderationsforinstallingyour
new Punch amplifier. Checking your battery and present sound system, as
well as pre-planning your system layout and best wiring routes will save
installationtime. Whendecidinghowtolayoutyournewsystem,besurethat
each component will be easily accessible for making adjustments.
Before beginning any installation, be sure to follow these simple rules:
1. Besuretocarefullyreadandunderstandtheinstructionsbeforeattempt-
ing to install the amplifier.
2. For safety, disconnect the negative lead from the battery prior to
beginning the installation.
3. Foreasierassembly,wesuggestyourunallwirespriortomountingyour
amplifier in place.
4. Route all of the RCA cables close together and away from any high
current wires.
5. Use high quality connectors for a reliable installation and to minimize
signal or power loss.
6. Think before you drill! Be careful not to cut or drill into gas tanks, fuel
lines, brake or hydraulic lines, vacuum lines or electrical wiring when
working on any vehicle.
7. Never run wires underneath the vehicle. Running the wires inside the
vehicle provides the best protection.
8. Avoid running wires over or through sharp edges. Use rubber or plastic
grommets to protect any wires routed through metal, especially the
firewall.
9. ALWAYS protect the battery and electrical system from damage with
proper fusing. Install a fuseholder and appropriate fuse on the +12V
power wire within 18” (45.7 cm) of the battery terminal.
10. When grounding to the chassis of the vehicle, scrape all paint from the
metal to ensure a good, clean ground connection. Grounding connec-
tions should be as short as possible and always be connected to metal
that is welded to the main body, or chassis, of the vehicle.