PUNCH 4020 DSM
4-CHANNEL AMPLIFIER
INSTALLATIO N & O PERATIO N
®
®
TABLE O F CO N TEN TS
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
G E T T I N G ST A R T E D
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-
cations and Warranty Information. For those of you who want quick
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
findingnew waysto improve ourproduct, thisinformation issubject
to change without notice.
I N T R O D U C T I O N
The Punch 4020 is a 4-channel amplifier which offers 20 Watts
per channel when driven into 4 Ohms. The amplifier utilizes a 2/
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-
pology which is a fast, short loop circuit allowing the output stage
to be driven with a low voltage drive signal. With the addition of
a 2/4 input selector switch and XCard crossovers, the 4020 can
be configured in many popular system designs without the added
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.
P U N C H 4 0 2 0 AM P LI FI ER
AC C ESSO RY P AC K
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"
– 1 –
RO C KFO RD FO SG AT E AC C ESSO RI ES
The following accessories were 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
needed by amplifiers to reproduce musical transients. The Punch
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
the coupling process, the Punch Link adds the finishing touch 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
XM70
XM100 = 100Hz
XM150 = 150Hz
XM200 = 200Hz
=
=
50Hz
70Hz
XM275 = 275Hz
XM400 = 400Hz
XM4.5k = 4,500Hz
XM6.5k = 6,500Hz
XM00 = Blank card for
custom crossover
– 2 –
TECH NICAL DESIGN FEATURES
◆ trans• ana
The trans• ana (TRANS conductance Advanced Non-multiplying
Amplifier) is a novel circuit that utilizes a short-loop complemen-
tary topology and advanced Real Time Protection circuitry.
THE RESULT: An amplifier design with the benefits of tube and bi-
polar transistor amplifier design without the limitations of either.
◆ MOSFET Devices
Rockford Fosgate is one of the few manufacturers in any of the
sound communities to utilize MOSFET devices in both the 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-
bines the advantages of both discrete components and integrated
circuitry. Rockford Fosgate is the only American amplifier manu-
facturer to have invested millions into this process. DSM compo-
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
copper paths where needed. Their short lead-out structures allow
maximum audio performance and highest signal-to-noise ratios
– 3 –
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.
Component
Figure 1
Solder
Solder
Thru-Hole
Surface Mount
◆ TOPAZ (Tracking Operation Pre-Amplifier Zone)
The TOPAZ (Tracking Operation Pre-Amplifier Zone) circuitry
solves ground loop noise problems common to automotive
amplifier design. This innovative new development allows vastly
improved isolation of the input signal grounds 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: Elimination of troublesome ground loop noise
between source and amplifier.
– 4 –
◆ 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 crossover frequencies and slope configurations
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. NOMAD makes advanced decisions based on device voltages
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.
– 5 –
PUNCH 4020 D E SI G N FE AT U R E S
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.
3
8
3
8
6
6
R
L
R
L
+
L
–
+
R
–
–
L
+
–
R
+
(Bridged Mono)
Front Speakers
(Bridged Mono)
Rear
Rear Speakers
Front
4
5
10
POWER
REM
B+
GND
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 spade terminal is used for the AP (auto
power) or remote turn on of the Punch amplifier.
– 6 –
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 – This switch allows selection of 2 channel
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.
Theycan be adjusted to match inputlevelsrangingfrom 150mV
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.
®
®
D S M
A M P LIFIER
20 Watts x 4 into 4Ω at 0.05% THD
30 Watts x 4 into 2Ω at 0.1% THD
®
RO CKFO RD CO RP O RATIO N
M ADE IN THE USA
High Pass
Low Pass
Full Range
H P
LP
L P
↕
FULL
HP
9
7
XCard
1
XCard
2
Front
Rear
XCard
XCard
– 7 –
IN STALLAT I O N C O N SI D ERAT I O N S
The following is a list of tools you will need for installing the Punch
amplifier:
Allen wrenches 7/64" & 3/32" (included) Voltmeter
Wire strippers
Electric hand drill w/assorted bits
Wire crimpers
Battery post wrench
Wire cutters
Assorted connectors
This section focuses on some of the vehicle considerations for
installing your new Punch amplifier. Checking your battery and
present sound system, as well as pre-planning your system layout and
best wiring routes will save installation time. When deciding how to
lay out your new system, be sure that each component will be easily
accessible for making adjustments.
Before beginninganyinstallation, be sure to follow these simple rules:
1. Be sure to carefully read and understand the instructions before
attempting to install the amplifier.
2. For safety, disconnect the negative lead from the battery prior to
beginning the installation.
3. For easier assembly, we suggest you run all wires prior to
mounting your 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 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.
Groundingconnectionsshould be asshortaspossible and always
be connected to metal that is welded to the main body, or chassis,
of the vehicle.
– 8 –
MO UNTING LO CATIO N
The mountinglocation and position ofyouramplifierwillhave a great
effect on its ability to dissipate the heat generated under normal
operation. The design of our cast aluminum heatsink serves to easily
dissipate the heat generated over a wide range of operating condi-
tions. However, to maximize the performance of your amplifier, care
should be taken to ensure adequate ventilation.
Trunk Mounting
Mounting the amplifier vertically on a surface with the fin grooves
running up and down will provide the best cooling of the amplifier.
Mountingthe amplifieron the floorofthe trunkwillworkbutprovides
less cooling capability than vertical mounting.
Mounting the amplifier upside down to the rear deck of the trunk will
not provide proper cooling and will severely affect the performance
of the amplifier and is strongly not recommended.
Passenger Compartment Mounting
Mounting the amplifier in the passenger compartment will work as
long as you provide a sufficient amount of air for the amplifier to cool
itself. If you are going to mount the amplifier under the seat of the
vehicle, you must have at least 1" (2.54cm) of air gap around the
amplifier's heatsink.
Mounting the amplifier with less than 1" (2.54cm) of air gap around
the amplifier's heatsink in the passenger compartment will not
provide propercoolingand willseverelyaffectthe performance ofthe
amplifier and is strongly not recommended.
Engine Compartment Mounting
Rockford Fosgate amplifiers should never be mounted in the engine
compartment. Not only will this void your warranty but could create
an embarrassing situation caused by the ridicule from your friends.
– 9 –
BATTERY AN D CH ARG IN G
Amplifiers will put an increased load on the vehicle's battery and
charging system. We recommend checking your alternator and
battery condition to ensure that the electrical system has enough
capacity to handle the increased load of your stereo system. Stock
electrical systems which are in good condition should be able to
handle the extra load of any Rockford amplifier without problems,
although battery and alternator life can be reduced slightly. To
maximize the performance of your Rockford Fosgate amplifier, we
suggest the use of a heavy duty battery, high output alternator and a
stiffening capacitor like the Rockford Fosgate PCH-C1.
W I R I N G T H E SYST E M
CAUTION: Avoid running power wires near the low level input
cables, antenna, power leads, sensitive equipment or harnesses. The
power wires carry substantial current and could induce noise into the
audio system.
1. Plan the wire routing. Take care when running signal level RCA
cablesto keep them close togetherbutisolated from the amplifier's
power cables and any high power auto accessories, especially
electric motors. This is done to prevent coupling the noise from
radiated electrical fields into the audio signal. When feeding the
wires through the firewall or any metal barrier, protect them with
plastic or rubber grommets to prevent short circuits. Leave the
wires long at this point to adjust for a precise fit at a later time.
2. Prepare the Power cable for attachment to the amplifier by
stripping 5/8" of insulation from the end of the wire. The use of 8
gauge power cable can interfere with the installation of the end
caps. Proper wire dress can prevent this from occurring. To
prevent the wire from fraying, strip the insulation at a 45° angle.
Insert the bared wire into the B+ terminal with the long side of the
insulation on the top. Bend the cable down at a 90° angle. Tighten
the set screw to secure the cable in place.
NOTE: The B+ cable MUST be fused 18" or less from the vehicle's
battery. Install the fuseholder under the hood and prepare the
cable ends as stated above. Connections should be water tight.
– 10 –
3. Prepare a length ofcable to be used forthe ground connection.
Strip 5/8" of insulation from the end of the cable as described
above and connect to the appropriate terminal of the ampli-
fier. Prepare the chassis ground by scraping any paint from the
metal surface and thoroughly clean the area of all dirt and
grease. Strip the other end of the wire and attach a ring
connector. Fasten the cable to the chassis using a screw.
4. Prepare the REM turn-on wire for connection to the amplifier
by stripping 5/8" of insulation from the wire end and crimping
an insulated spade connector in place. Slide the connector
over the REM terminal on the amplifier. Connect the other end
of the REM wire to a switched 12 volt positive source. The
switched signal is usually taken from the source unit's auto
antenna or the accessory lead. If the source unit does not have
these outputs available, the recommended solution is to wire
a mechanical switch in line with a 12 volt source to activate
the amplifier.
5. Connectthe source signalto the amplifierbypluggingthe RCA
cables into the input jack(s) at the amplifier.
6. Connect the speakers. Strip the speaker wires 5/8" and insert
into the appropriate terminal on the amplifier. Insert the bared
wire into the speaker terminal and tighten the set screw to
secure into place. Be sure to maintain proper speaker polarity.
DO NOT chassis ground any of the speaker leads as unstable
operation may result.
7. Perform a finalcheckofthe completed system wiringto ensure
that all connections are accurate. Check all power and ground
connections for frayed wires and loose connections which
could cause problems from road vibrations.
8. After the final inspection is complete, install the power fuse
and enjoy listening. During the initial listening period, you
may need to “fine tune” any phasing and level settings within
your particular vehicle. To aid in this procedure, play a track
with high musical content and cruise around your neighbor-
hood. After fully evaluating the transient response of your
system and making any final adjustments, all your neighbors
within a 1 mile radius will assume that you have just success-
fully completed another upgrade to your audio system for
which they will probably spill thumbtacks on your driveway.
– 11 –
U SI N G T H E XCARD
The crossover functions are controlled through the use of an
XCard and can be set for high-pass, low-pass or full range
operation. These cards are shipped in the most common fre-
quency. Each crossover card has two faces: one face operates Full
Range, the other has arrows to indicate the edge for selecting HP
(high-pass) or LP (low-pass) operation. Orient the card with the
desired operating edge, indicated by the arrow, toward the socket
terminals inside the amplifier. Firmly, but carefully, plug the card
into the socket.
High Pass
Low Pass
Full Range
H P
LP
L P
↕
FULL
HP
The crossover point can be altered by changing the resistor value.
Use the following formula to select the appropriate resistor value
to be placed on the XCard.
3386
= R (in kΩ) for .047µf cap
The actual formula is:
f
o
1
R =
7234
2πf c
= R (in kΩ) for .022µf cap
o
f
o
Crossover Card
HigPass
LoPass
FulRange
FULL
Where: R = Ω
f = desired crossover frequency
o
c = capacitor in farads
-6
ex: .047 x 10 for .047mf cap
– 12 –
4 0 2 0 PO W ER CO N N EC TI O N S
4
5
10
POWER
REM
B+
GND
Connect to remote
turn-on lead of
source unit.
Connect to chassis
ground of vehicle*
Less than 18"
Connect to B+ of battery
with a 30 amp fuse.
*Keep grounds as short as possible.
– 13 –
SAM P L E W I R I N G D I AG R AM S
4-CHANNEL STEREO
Rear
Front
R
L
R
L
+
L
–
+
R
–
–
L
+
–
R
+
(Bridged Mono)
Front Speakers
(Bridged Mono)
Rear Speakers
Rear
Front
+
–
+
–
2Ω Minimum
High Frequency
–
+
–
+
2Ω Minimum
Low Frequency
Rear XCard*
Front XCard*
HP
LP
XCard
1
XCard
2
*Note: XCard can be inserted in HP,
LP, or Full Range.
• Signal input switch to 4 channel input.
• Gain for Front and Rear operate independently.
• Front is operating in stereo.
• Rear is operating in stereo.
• Experiment with subwoofer polarity to determine
which sounds best in your system.
– 14 –
4-CHANNEL – STEREO FRONT
MONO REAR
Rear
Front
R
R
L
+
L
–
+
R
–
–
L
+
–
R
+
L
(Bridged Mono)
Front Speakers
(Bridged Mono)
Rear Speakers
Rear
Front
–
+
+
–
+
–
4Ω Minimum
2Ω Minimum
High Frequency
Low Frequency
Rear XCard*
Front XCard*
HP
LP
XCard
1
XCard
2
*Note: XCard can be inserted in HP,
LP, or Full Range.
• Signal input switch to 4 channel input.
• Gain for Front and Rear operate independently.
• Front is operating in stereo.
• Rear is operating in stereo.
• Fader on source unit controls level of subwoofer.
• Experiment with subwoofer polarity to determine
which sounds best in your system.
– 15 –
2-CHANNEL – MONO
Rear
Front
R
L
R
L
+
L
–
+
R
–
–
L
+
–
R
+
(Bridged Mono)
Front Speakers
(Bridged Mono)
Rear Speakers
Rear
Front
+
–
–
+
4Ω Minimum
4Ω Minimum
Low Frequency
Low Frequency
Rear XCard*
Front XCard*
LP
LP
XCard
1
XCard
2
*Note: XCard can be inserted in HP,
LP, or Full Range.
• Signal input switch to 2 channel input.
• Gain for Front and Rear operate independently.
• Front is operating in mono.
• Rear is operating in mono.
– 16 –
4-CHANNEL – STEREO/MONO FRONT
STEREO REAR
Rear
Front
R
L
R
L
+
L
–
+
R
–
–
L
+
–
R
+
(Bridged Mono)
Front Speakers
(Bridged Mono)
Rear Speakers
Rear
Front
+
–
+
–
2Ω Minimum
2Ω Minimum
High Frequency
High Frequency
–
+
–
+
+
–
2Ω Minimum
High Frequency
4Ω Minimum
Low Frequency
Rear XCard*
Front XCard*
HP
Full Range
XCard
1
XCard
2
Note: XCard can be inserted in HP,
LP, or Full Range.
• Signal input switch to 4 channel input.
• Gain for Front and Rear operate independently.
• Front is operating in stereo/MONO.
• Rear is operating in stereo.
• Fader on source unit controls level of rear.
– 17 –
TR O U BL E SH O O T I N G
Symptom
Diagnosis
Remedy
Amplifier doesnot
turn on.
Voltage applied to the Check the alternator, bat-
REM terminal of the tery, fuse, and wiring and
(Power LED is off) amplifierisnotbetween repair as necessary. If the
10.5 and 15.5 volts or voltage is above 15.5 volts,
there is no voltage have the electrical system
present.
inspected by an authorized
car service center.
Voltage to the B+ termi- Check the alternator, bat-
nal of the amplifier is tery, fuse, and wiring and
not between 10.5 and repair as necessary. If the
15.5 volts or there is no voltage is above 15.5 volts,
voltage present.
have the electricalinspected
by an authorized car service
center.
Amplifier is not prop-
erly grounded.
Check wiring and repair as
necessary.
Check connections, substi-
tute with known working
source and cablesand repair
or replace as necessary.
RCA Input from source
unit is not connected or
notfunctioningproperly.
Amplifier has no
sound.
(Power LED is on)
Checksignalinputswitchand
XCard positions and repair
or replace as necessary.
XCards are missing or
not placed properly in
crossover slots and/or
switches are not prop-
erly selected.
Disconnect existing speak-
ers and test with known
working speakers and wires.
If amplifier plays, check and
repair wiring and installa-
tion of speakers as neces-
sary.
Speaker leads are
shorted to each other or
to the chassis of the ve-
hicle.
Replace speakers.
Speakers are defective.
– 18 –
Symptom
Diagnosis
Remedy
Readjust input gains of
amplifier.
Speaker Output
Low or Distorted
Input gain signal for
amplifier set too low.
Check system with known
working source and repair
orreplace orignalsource as
needed.
Source unit output too
low.
Check speaker polarity and
correct as needed.
Speakers wired out of
polarity from the left to
right channel.
Check signal input switch
and XCard positons and
repair or replace as neces-
sary.
XCards are missing or
not placed properly in
crossover slots and/or
switch not properly se-
lected.
Check the alternator, bat-
tery, fuse and wiring and
repair as necessary.
Low battery voltage or
large voltage drops to
the amplifierunderload.
Voltage spike from out-
put of preceding com-
ponent is entering am-
plifierthrough inputsig-
nal.
Disconnectinputsignalto
amplifier and turn ampli-
fier on and off. If noise is
eliminated, connect REM
lead of amplifier to source
unit with a delay turn-on
module.
Amplifier Noise
(Turn-on Pop)
Voltage spike from re-
mote turn-on lead is
entering through REM
input terminal.
Use different 12 volt
source for REM lead of
amplifier. (i.e., battery di-
rect)Ifnoise iseliminated,
use relay to isolate ampli-
fier from noisy turn-on
output.
– 19 –
Symptom
Diagnosis
Remedy
Disconnect existing speak-
ers and test with known
working speakers. If engine
noise is gone, check and
repair wiring and installa-
tion of speakers as neces-
sary.
Engine Noise on
the Speaker Out-
puts of the Ampli-
fier
Speaker leads are
shorted to each other or
to the chassis of the ve-
hicle.
Check connections, substi-
tute with known working
cablesand repairorreplace
as necessary.
RCA input from source
unit is not connected or
not functioning prop-
erly.
Run the RCA cable on a
different route.
RCA cable is picking up
radiated noise.
Disconnect antenna from
the source unit. If engine
noise is gone, check, and
repair wiring and installa-
tion or use an antenna
ground loop isolator.
Ground loop in antenna
line.
Bypass all other equipment
(crossovers and equalizers)
byconnectingthe head unit
directly to the amp. If noise
is gone, reconnect equip-
ment one piece at a time
and test for noise after each
install.
Multiple grounding
pathsin the signal chain.
• If noise persists, see your Authorized Rockford Fosgate Dealer.
– 20 –
D YN AM I C P O W E R M E ASU R E M E N T S
About the Dynamic Power Measurements
The Audio Graph PowerCube is a test instrument used to measure the
output of an amplifier in accordance with IHF-202 industry stan-
dards. The IHF-202 standard is a dynamic power measurement and
was developed as a means of measuring power in a manner that best
represents the Real World operation of an amplifier. Many manufac-
turers, including Rockford Fosgate, at times will measure amplifier
power into a fixed resistor (4 Ohm, 2 Ohm). While this method is
useful in some types of evaluation and testing, it is not representative
of an amplifier that is connected to a speaker and playing music.
Music
Music is dynamic; the sound waves are complex and constantly
changing. In order to simulate this, the IHF-202 standard calls for the
input signal to the amplifier to be a 1kHz bursted tone. This signal is
input (on for 20 milliseconds) and reduced 20dB for 480 millisec-
onds. The signal is gradually increased in level until the amplifier's
output exceeds 1% Total Harmonic Distortion (THD). At 1% distor-
tion becomes audible, therefore, any power produced above that
level is considered not usable. Many manufacturers represent their
amplifiers' output power in excess of 10% distortion. They use many
names for this measurement, such as Total Maximum Power or
Maximum Output Power. This is not indicative of the actual usable
output power.
Listening to Loudspeakers - Not Resistors
A loudspeaker is not a resistor. A resistor's value (resistance measured
in ohms) is fixed. A loudspeaker's impedance is dynamic. It is
constantly changing in value, dependent upon the frequency of the
input signal. Therefore, measuring power with the amplifier loaded
into a 4 ohm resistor is not the same as measuring power with the
amplifier connected to a 4 ohm speaker. Most people do not listen to
music through a resistor.
A4 Ohm speakermayexperience a drop in impedance 4-6 timeslower
than its nominal (printed) impedance. A speaker will also create phase
shifts in the signal that is passed through it. These phase shifts happen
because a speaker is an inductor (voice coil) and a capacitor (compli-
ance of the surround/spider), as well as a resistor (voice coil wire).
To simulate a speaker the Audio Graph PowerCube measures output
power into 20 different loads. It tests at 8 Ohms, 4 Ohms, 2 Ohms and
1 Ohm. Each ofthese impedancesisalso tested at–60°, –30°, 0°, +30°
and +60° phase angles. These different impedances and phase angles
representthe shiftsin impedance and phase thatcan occurin a typical
loudspeaker.
Appendix A
– 21 –
Information Cubed
The data acquired in the testing procedure is then graphed in the form
of a 3-dimensional cube. Hence the name PowerCube.
The Phase Angle is expressed on the horizontal axis, the Output
Voltage is presented on the vertical axis and the Impedance is
displayed on the Z axis. Output Power, in watts, is listed on the left
hand side for each impedance at each phase angle.
AudioGraph – The PowerCube
MODEL BEING
TESTED
VOLTAGE FROM
BATTERY
x2 = STEREO
MONO = BRIDGED MONO
Amplifier: PUNCH AMP 14.4V x 2
Serial No:
Rated Power : Rated Output - Watts per Channel
Owner
:
ROCKFORD CORPORATION
8Ω –60° 84
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
*
–30° 84
0° 83
POWER
IN
50V
30V
30° 84
60° 85
WATTS
{
4Ω –60° 159
*
–30° 154
0° 153
30° 154
60° 158
10V
2Ω –60° 266
*
–30° 251
0° 245
8Ω
4Ω
30° 248
60° 261
2Ω
–60° (Cap)
0°
1Ω
1Ω –60° 378
*
{
(Ind) +60°
{
–30° 343
0° 333
Impedance
PHASE ANGLES
30° 339
60° 373
What is an Amplifier?
An amplifier by definition is a voltage generating device, recreating
the signal which is input to it identically but with increased volume.
It will be connected to a reactive load (the speaker). The impedance
of this load and phase of the signal passing through the load will vary,
dependent upon the frequency of the input signal (music).
Therefore, a perfect amplifier will be able to maintain the same output
voltage regardless of load characteristics and will not alter the signal
it is reproducing. A perfect amplifier when measured by the
AudioGraph PowerCube would present data that forms a perfect
cube. Unfortunately, amplifiers are not perfect. The laws of physics
generally prevent it. A great amplifier is about the best one can hope
to attain.
As you can see by the PowerCube and as you will experience by
listening, your Punch amplifier is a GREAT AMPLIFIER!
– 22 –
SP EC I FI C AT I O N S
Continuous Power Rating (Competition Standard) - Measured at 13.8V
RMS continuous power per channel, all channels 20 Watts
driven into a 4Ω load from 20-20,000Hz with
less than 0.05% Total Harmonic Distortion (THD)
RMS continuous power per channel, all channels 30 Watts
driven into a 2Ω load from 20 to 20,000Hz, with
less than 0.1% THD
RMS continuous power bridged into a 4Ω load
60 Watts
from 20 to 20,000Hz, with less than 0.10% THD
Dynamic Power Rating (IHF-202 Standard) - Measured at 14.4V
Mono into a 4Ω Load
Per channel into a 2Ω Load
Per channel into a 4Ω Load
82 Watts
41 Watts
26 Watts
Signal-to-Noise Ratio
>100dB
A-weighted
Factory Default Crossover Point
Crossover Alignment
Dimensions
100Hz Butterworth
12dB/octave
9-5/8" W x 12-5/8" L x 2-5/8" H
(24.4cm) x (32.0cm) x (6.6cm)
Damping Factor @ 4Ω (at output connetor)
Bandwidth
Frequency Response
>150
15Hz-100kHz ±3dB
20Hz-20kHz
±0.5dB
Slew Rate
30 Vµs
IM Distortion (IHF)
Input Sensitivity
<0.05%
Variable from
150mV to 3V
Preset at the
factory for 500mV
30 Amp
Fuse size
Input Impedance
20k Ohms
Specifications are subject to change without notice.
– 23 –
W ARRAN TY IN FO RMATIO N
Rockford Fosgate warrants all electronics to the original consumer/purchaser to
be free from defects in materials or workmanship for a period of three (3) years.
We will cover parts and labor provided the product was purchased from an
Authorized Rockford Fosgate Dealer. This warranty does not apply to any product
on which the seals and/or serial number have been broken, removed, tampered
with, defaced or altered in any manner. This warranty only applies to the original
consumer/purchaser and is not transferable.
Electronics found to be defective during the warranty period will be repaired or
replaced at Rockford Fosgate’s discretion. Repaired or replaced electronics will
be covered by the balance of the original warranty period only. Rockford Fosgate
shall not be responsible for any incidental or consequential damages resulting
from a defect in electronics. Some states do not allow the exclusion or limitation
of incidental or consequential damages, so the previous limitation may not be
applicable.
The warranty does not cover any appearance item, any cost or expense related to
the removal or reinstallation of the product, any accessory used in conjunction
with the product, damage to the product resulting from alteration, accident,
misuse or abuse, or improper installation. This warranty does not apply if the parts
or labor, which would otherwise be provided without charge under this warranty,
are obtained from any source other than Rockford Fosgate or an Authorized
Rockford Fosgate Service Center.
This warranty is the only express warranty and does not create any implied
warranties. Rockford Fosgate limits its obligations under any implied warranties
under state laws to a period not to exceed the written warranty period. Some states
do not allow limitation on how long an implied warranty lasts, so the above
limitation maynotapply. Thiswarrantyappliesonlyto productssold in the United
States of America or its possessions. For warranty outside the U.S.A., please
contact the nearest Authorized Rockford Fosgate Dealer. This warranty gives the
consumerspecific legalrights, and the consumermayhave otherrightswhich vary
from state to state.
A defective product must be shipped prepaid to the Authorized Rockford Fosgate
Dealer from which the consumer purchased the product or to the Rockford
Fosgate factoryin Tempe, Arizona in the originalfactorycarton orequivalent. Any
shipping loss or damage will be borne by the consumer or the consumer’s shipper.
A consumer returning a product to the factory must call (800) 669-9899 for a
Return Authorization Number. All shipments shall be clearly marked with the
Return Authorization Number on the outside of the shipping carton.
Ship to:
Rockford Corporation
Warranty Repair Department
2055 E. 5th Street
Tempe, AZ 85281 U.S.A.
Return Authorization Number:_________________
Rockford Fosgate
Rockford Corporation
546 South Rockford Drive
Tempe, Arizona 85281 U.S.A.
In U.S.A., (602) 967-3565
In Canada, call Korbon (905) 567-1929
In Europe, Fax (49) 4207-801250
In Japan, Fax (81) 559-79-1265
10/94
MAN-0808-A
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