Rockford Fosgate PUNCH 4020 DSM User manual


PUNCH 4020 DSM
4-CHANNEL AMPLIFIER
®®
INSTALLATION & OPERATION

Dear Customer,
Congratulations on your purchase of the world's finest brand of car audio
amplifiers. At Rockford Fosgate we are committed to musical reproduction at its
best, and we are pleased you chose our product. Through years of engineering
expertise, hand craftsmanship 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
specializedtrainingthroughRockfordTechnicalTrainingInstitute(RTTI). Please
read your warranty and retain your receipt and original carton for possible future
use.
ToaddthefinishingtouchtoyournewRockfordFosgateimageorderyourRockford
accessories, which include everything from T-shirts and jackets to hats and
sunglasses.
To get a free brochure on Rockford Fosgate products and Rockford accessories,
please call 602-967-3565 or FAX [phone]. In Canada, call Korbon
Tradingat905-567-1929.ForInternationalorders,FAX[phone]
or call +001-1-602-967-3565.
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
verification of your factory warranty and may become useful in recovering
your amplifier if it is ever stolen.
Serial Number: ____________________
Model Number:____________________
If, after reading your manual, you still have questions regarding this
product, we recommend that you see your Rockford Fosgate dealer. If you
needfurtherassistance,youcancallusdirectat1-800-795-2385.Besureto
have your serial number, model number and date of purchase available
when you call.
PRACTICE SAFE SOUND™
CONTINUOUS EXPOSURE TO SOUND PRESSURE LEVELS
OVER100dBMAYCAUSEPERMANENTHEARINGLOSS.HIGH
POWEREDAUTOSOUNDSYSTEMSMAYPRODUCESOUND
PRESSURE LEVELS WELL OVER 130dB. USE COMMON SENSE
AND PRACTICE SAFE SOUND.

GETTING STARTED
TABLE OF CONTENTS
Introduction ...................................................................................... 1
Punch 4020 Amplifier Accessory Pack .............................................. 1
Rockford Fosgate Accessories............................................................ 2
Technical Design Features ................................................................ 3
Punch 4020 Design Features............................................................. 6
Installation Considerations ................................................................ 8
Mounting Location............................................................................ 9
Battery and Charging....................................................................... 10
Wiring the System ........................................................................... 10
Using the XCard.............................................................................. 12
Sample Wiring Diagrams ................................................................ 14
Troubleshooting .............................................................................. 18
Dynamic Power Measurements....................................................... 21
Specifications.................................................................................. 23
Warranty Information...................................................................... 24
Welcome to Rockford Fosgate! This manual is designed to provide
information on the Punch 4020 amplifier for owner, salesperson
and installer. To accomplish this, the manual is divided into five
main sections: Introduction, Installation, Troubleshooting, Specifi-
cationsandWarrantyInformation.Forthoseofyouwhowantquick
information on how to install this product, please turn to the Basic
System Diagrams in the Installation section of this manual. Other
information can be located by using the Table of Contents. We, at
Rockford Fosgate, have worked very hard to make sure all the
information in this manual is current. But, as we are constantly
findingnewwaystoimproveourproduct,thisinformationissubject
to change without notice.

– 1 –
INTRODUCTION
The Punch 4020 is a 4-channel amplifier which offers 20 Watts
perchannelwhendriveninto4Ohms.Theamplifierutilizesa2/
4 input selector switch and XCard crossovers.
When building a 4-channel amplifier, a major design challenge
is to maintain sound quality in a limited space. For the Punch
4020, Rockford Fosgate Engineers designed the Trans• Ana to-
pologywhichisafast,shortloopcircuitallowingtheoutputstage
tobe driven witha low voltagedrive signal.Withthe additionof
a 2/4 input selector switch and XCard crossovers, the 4020 can
beconfiguredinmanypopularsystemdesignswithouttheadded
cost of external processors. The result is an excellent sounding
amplifier in a physically compact area.
The Punch 4020 satisfies the need for a powerful 4-channel
amplifier at a competitive price.
We strongly recommend you have your Authorized Rockford
Fosgate Dealer install the new Punch 4020 amplifier. If you do
choose to install it yourself, please be sure to read the entire
manual before beginning.
PUNCH 4020 AMPLIFIER
ACCESSORY PACK
The accessory pack shipped with the Punch 4020 amplifiers
include the mounting hardware necessary to secure it to the
vehicle as well as attaching the end caps.
Installation & Operation Manual
Punch Verification Certificate
(10)Hex Head screws for speaker and power connectors
(4) Mounting screws for end caps
(4) Mounting screws for amplifier
(1) Allen wrench 7/64"
(1) Allen wrench 13/32"

– 2 –
ROCKFORD FOSGATE ACCESSORIES
Thefollowingaccessorieswere designed to enhance the perfor-
mance of the Punch 4020 amplifier.
Energy Storage Capacitor (PCH-C1)
The Punch 1 farad capacitor is used to provide extra current
neededbyamplifierstoreproducemusicaltransients.ThePunch
Cap also has the natural ability to filter DC ripple caused by the
alternator which can result in noise in the system. The PCH-C1
will maximize both the sound quality and performance that
Rockford Fosgate amplifiers can deliver.
Punch Link (FG-LINK)
The Punch Link is a specially cast heatsink interconnect which
allows you to join any of our current Punch or Punch Power
amplifiers together. While providing additional cooling through
thecouplingprocess, the PunchLink adds thefinishingtouch by
giving you the look of one awesome amplifier.
XCard
Additional crossover card frequencies are available for special-
ized requirements. You can get the following XCards from your
Authorized Rockford Fosgate Dealer.
XM50 = 50Hz XM275 = 275Hz
XM70 = 70Hz XM400 = 400Hz
XM100 = 100Hz XM4.5k = 4,500Hz
XM150 = 150Hz XM6.5k = 6,500Hz
XM200 = 200Hz XM00 = Blank card for
custom crossover

– 3 –
TECHNICAL DESIGN FEATURES
◆trans• ana
Thetrans• ana (TRANSconductanceAdvancedNon-multiplying
Amplifier)isanovelcircuitthatutilizesashort-loopcomplemen-
tary topology and advanced Real Time Protection circuitry.
THERESULT:Anamplifierdesignwiththebenefitsoftubeandbi-
polar transistor amplifier design without the limitations of either.
◆MOSFET Devices
Rockford Fosgate is one of the few manufacturers in any of the
soundcommunitiestoutilizeMOSFETdevicesinboththe power
supply and the output stages . MOSFET (Metal Oxide Semicon-
ductor Field Effect Transistor) devices offer several important
inherent advantages over the 30 year old technology of bi-polar
design. These advantages include: thermal stability, switching
speed, ultra low output impedance and wider bandwidth linear-
ity. In addition, MOSFET and vacuum tubes share many impor-
tant operating characteristics. However, the MOSFET device is
much faster, wider in bandwidth, measurably lower in distortion
and far more linear than vacuum tubes.
THE RESULT: Operational characteristics of vacuum tubes
without the performance limitations of tube design.
◆DSM (Discrete Surface Mount) Technology
The DSM (Discrete Surface Mount) manufacturing process com-
binestheadvantagesofbothdiscretecomponentsandintegrated
circuitry.RockfordFosgateis theonlyAmericanamplifiermanu-
facturerto haveinvested millionsinto thisprocess. DSMcompo-
nents differ from conventional discrete components in three
different ways. They are more compact and more rugged, and
they take much better advantage of the PC board to allow them
to get rid of any heat they generate. Using them wherever
appropriate allows the advantages associated with discrete thru-
hole circuitry to be retained while also providing room for both
highly advanced processing features and generous PC board
copperpathswhereneeded.Theirshortlead-outstructuresallow
maximum audio performance and highest signal-to-noise ratios

– 4 –
to be obtained in amplifiers of desirable package size without
resorting to “amplifier-on-a-chip”shortcuts. These advantages
are shown below in Figure 1.
THE RESULT: Less connections, improved reliability, shorter
signal paths, superior signal-to-noise ratio and awesome sonic
performance.
Figure 1
Thru-Hole Surface Mount
Component
Solder Solder
◆TOPAZ (Tracking Operation Pre-Amplifier Zone)
The TOPAZ (Tracking Operation Pre-Amplifier Zone) circuitry
solves ground loop noise problems common to automotive
amplifierdesign.Thisinnovativenewdevelopmentallowsvastly
improved isolation of the input signal grounds from the power
supplygroundoftheamplifier.Thisisaccomplishedbyallowing
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: Elimination of troublesome ground loop noise
between source and amplifier.

– 5 –
◆XCard (Internal Crossover)
The Punch 4020 amplifier utilizes internal active crossovers. These
crossovers have many performance advantages such as using dis-
crete components for exact frequency adjustments which are far
superior to potentiometers. Additionally, the XCard can be config-
ured for high-pass, low-pass and full range operation. With slight
modification,many crossoverfrequencies andslopeconfigurations
can be achieved.
THE RESULT: Increased system design flexibility with a precise
electronic crossover without the limitations of conventional poten-
tiometer designs.
◆RTP (Real Time Protection)
NOMAD (NOn-Multiplying Advanced Decision)
The Punch 4020 amplifier uses an analog computer process to
absolutely maximize safe output power under all operating condi-
tions. Rockford Fosgate pioneered and developed RTP (Real Time
Protection), a crucial element in the performance edge of our
amplifiers. The innovative NOMAD (NOn-Multiplying Advanced
Decision) system is the most sophisticated version of this technique
ever used, bringing previously unavailable levels of accuracy,
stability, temperature immunity and reliability to this critical pro-
cess.NOMADmakesadvanceddecisionsbasedondevicevoltages
to precisely control the 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.

PUNCH 4020 DESIGN FEATURES
1. Cast Aluminum Heatsink – The cast aluminum heatsink of the
Punch amplifier dissipates heat generated by the amplifier's
circuitry. The inherent advantage of casting provides a 30%
improvement of cooling over conventional extrusion heatsink
designs.
2. End Caps – Interchangeable end caps conceal the wiring and
input cables, giving the amplifier a clean “stealth” look.
– 6 –
3. SpeakerTerminals–Theheavyduty,gold-platedterminalblock
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 spade terminal is used for the AP (auto
power) or remote turn on of the Punch amplifier.
Front Gain
Front Rear
R
L
Rear Gain
Rear Speakers
386683
– L +
(Bridged Mono)
R
L
–R +
Front Speakers
+ L –
(Bridged Mono)
+ R –
REM B+ GND
4
510
POWER

– 7 –
6. RCA Input Jacks – The industry standard RCA jack provides an
easy connection for signal level input. They are gold-plated to
resist the signal degradation caused by corrosion.
7. Signal Input Switch– Thisswitchallowsselectionof2channel
or 4 channel source unit feed.
8. Input Sensitivity Controls – The input level controls are preset
for 500mV which will match the output of most source units.
Theycanbeadjustedtomatchinputlevelsrangingfrom150mV
to 3V.
9. Internal Crossovers – These built-in crossover cards are
configurable for a multitude of operating frequencies. The
orientation of the card in its socket determines the function of
high-pass, low-pass, or full range operation.
10. LED Power Indicator – The LED illuminates when the unit is
turned on.
Low Pass Full RangeHigh Pass
FULL
↕
HP
➝
➝
LP
HP
➝
➝
LP
®
DSM
XCard 2
ROCKFORD CORPORATION
MADE IN THE USA
®
Rear
XCard Front
XCard
®
20 Watts x 4 into 4Ωat 0.05% THD
30 Watts x 4 into 2Ωat 0.1% THD
AMPLIFIER
XCard 1
79