Congratulations on your purchase of the world's finest brand of car audio amplifiers. At Rockford Fosgate we
are fanatics about 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 specialized training through Rockford Technical Training
Institute (RTTI). Please read your warranty and retain your receipt and original carton for possible future use.
Great product and competent installations are only a piece of the puzzle when it comes 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 fanatic image order your Rockford Fosgate wearables, which include
everything from T-shirts and jackets to hats and sunglasses.
To get a free brochure on Rockford Fosgate products and Rockford wearables, please call 602-967-3565 or FAX
602-967-8132. For International orders, FAX +001-1-602-967-8132 or call +001-1-602-967-3565.
IGHPOWEREDAUTOSOUNDSYSTEMSMAYPRODUCESOUNDPRESSURELEVELSWELLOVER 130dB. USE
H
COMMON
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.
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.
SENSEANDPRACTICESAFESOUND.
Serial Number:_____________________________________________
Model Number: ____________________________________________
50.2 Design Features ...................................................................................................................................................5
50.1 Design Features ...................................................................................................................................................7
Battery and Charging .................................................................................................................................................10
Wiring the System......................................................................................................................................................11
Using Passive Crossovers............................................................................................................................................12
Table of Crossover Component Values ..........................................................................................................................13
Using the XCard.........................................................................................................................................................14
Customizing the XCard ...............................................................................................................................................14
Using the 50.2 Signal Switching Network......................................................................................................................19
Using the 50.2 Balanced Line Inputs ............................................................................................................................24
Using the 50.1 Signal Switching Network......................................................................................................................31
System Diagrams.......................................................................................................................................................34
Warranty Information .................................................................................................................................................48
International Information.............................................................................................................................................49
G
ETTING
S
TARTED
Welcome to Rockford Fosgate! This manual is designed to provide information 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 worked very hard to make sure all the information in this manual is current. But, as we are constantly finding new ways
to improve our product, this information is subject to change without notice.
I
a
O
p
d
e
v
r
a
a
n
t
c
i
e
o
d
n
Sections marked
ADVANCED
OPERATION
include in-depth
technical information
include “slam dunk”
®®
N
S
T
A
L
L
A
T
I
O
N
Sections marked
INSTALLATION
wiring connections
TROUBLE-
S
H
O
O
T
I
N
G
Sections marked
TROUBLESHOOTING
include recommendations
for curing installation
problems
I
NTRODUCTION
Rockford Fosgate is distinguished as the global leader in building high performance amplifiers. Since the introduction of the
2
250m
and 250m, new performance standards were set for sound quality and flexibility and have risen to an even higher
level with the introduction of the 50.2 and 50.1 “competition” amplifiers. The “50 series” utilize similar technologies of thei
predecessors like trans•
impedances.
The 50.2 is a two-channel amplifier which is optimized to drive 1Ω stereo and 2Ω bridged loads. The 50.1 is a singlechannel amplifier optimized to drive a 1Ω (single amp) or a 2Ω bridged load (pair of amps bridged to a single load).
The “50 series” use Rockford's innovative technologies for awesome sound quality, reliable performance and high output
power into low impedances. This can be beneficial for serious competition vehicles.
P
UNCH
A
MPLIFIER
The accessory pack shipped with the “50 series” Power amplifiers include the mounting hardware necessary to secure the
amplifier to the vehicle and to attach the end caps to the amplifier.
TO
50 S
nova
, TOPAZ and DIAMOND; however, they have enhanced power supplies for driving very low
A
ERIES
CCESSORY
P
ACK
r
Punch Power 50.2Punch Power 50.1
Installation & Operation ManualInstallation & Operation Manual
Punch Verification CertificatePunch Verification Certificate
(4) Amplifier mounting screws (#8 x 3⁄4" phillips)(4) Amplifier mounting screws (#8 x 3⁄4" phillips)
(8) Speaker & power connector screws (3/32" allen)(6) Speaker & power connector screws (3/32" allen)
(4) End cap mounting screws (9/64" allen)(4) End cap mounting screws (9/64" allen)
(1) Allen wrench 3/32"(1) Allen wrench 3/32"
(1) Allen wrench 9/64"(1) Allen wrench 9/64"
– 1 –
T
ECHNICAL
Many of the solutions to common design problems encountered by Rockford Fosgate engineers created entire new circuit
designs as well as new ways to construct the Punch 50.2 and 50.1 Power Amplifiers. In our flagship amplifiers, no expense
was spared in design and construction from the unique circuitry design to the manufacturing process that has proven to be
the industry reference for many years. Described below are just some of the accomplishments achieved by our engineering
and manufacturing staff.
D
ESIGN
F
EATURES
◆ trans•
The trans•
the audio signal to pass through the amplifier at
supply and is configured to increase power gain. The increase in power gain allows the drive stage to operate at a lower
voltage. A low voltage drive stage is the same principle used in high quality preamplifiers to produce high linearity and wide
bandwidth.
The resulting design utilizes an output stage with a simpler gain structure and a shorter total signal path than conventional
high voltage (bi-polar) designs. The number of stages is reduced from five or more to three. The output stage is further refined
into a trans-impedance stage (current to voltage converter) to achieve a short loop (fast) negative feedback. The output stage
is driven cooperatively by a transconductance stage (voltage to current converter).
THE RESULT: Superior sound quality, greater efficiency and higher reliability.
nova
nova
(TRANS conductance NOdal Voltage Amplifier) is a patented circuit (U.S. Patent 4,467,288) that allows
E-II-E
(TRANSconductance NOdal Voltage Amplifier)
low voltage
trans•nova circuitry
. Each amplifier channel utilizes its own “fully floating” power
design which reduces high frequency distortion. Amplifiers which utilize a large array of output MOSFETs cause a high
capacitive load on the driver stage. This load can make the high frequencies sound harsh. The DIAMOND circuit eliminates
high frequency distortion by allowing the driver to operate with 20dB or more of current headroom, whereas traditional drivers
have only 6dB of current headroom.
THE RESULT: Lower distortion and greater inherent stability.
(Dynamically Invariant AMplification Optimized Nodal Drive - patent pending) is an important advance in circuit
◆ 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 20-100 times better than amplifiers without TOPAZ.
THE RESULT: Elimination of troublesome ground loop noise between source and amplifier.
– 2 –
◆ DSM (Discrete Surface Mount Technology)
The
DSM
(Discrete Surface Mount) manufacturing process combines the advantages of both discrete components and
integrated circuitry. Rockford Fosgate is the only American amplifier manufacturer to have invested millions into this process.
DSM components differ from conventional discrete components in different ways. They are more compact, more rugged,
and they efficiently dissipate generated heat. Using them wherever appropriate allows 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 “amplifier-on-a-chip” shortcuts. These
advantages are shown below in Figure 1.
Solder
Component
Solder
PC Board
Figure 1
PC Board
Thru-HoleSurface Mount
THE RESULT: Less connections, improved reliability, shorter signal paths, superior signal-to-noise ratio and awesome sonic
performance.
◆ XCard (Internal Crossover)
The Power amplifiers utilize internal active crossovers. These crossovers have many performance advantages such as using
discrete components for exact frequency adjustments which are far superior to potentiometers. Additionally, the
be configured 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
potentiometer designs.
XCard
can
◆ Stereo Pass-Thru
The
Pass-Thru
cables or “Y” adapters. The 50.1 Pass-Thru provides constant Full Range stereo output. The 50.2 has the ability to provide
constant Full Range stereo output as well as distribute one of its internal XCards to the Pass-Thru for a dedicated High-Pass
or Low-Pass output.
THE RESULT: Convenient signal level output for adding extra amplifiers.
output provides a convenient source for daisy-chaining an additional amplifier without the need for extra RCA
– 3 –
◆ Balanced Line Inputs (50.2)
Using the Balanced Line Inputs provides the last word in achievable rejection of noise induced in the cable between the source
and the amplifier. The differential input circuitry (Figure 2) used
in the balanced input system rejects whatever signals are
common to both of the shielded, twisted-pair conductors. Balanced line is universal in concert installations where the stage
and mixing consoles are hundreds of feet apart. Long signal
Figure 2
Center
Conductor
Outer
Shield
Differential inputs only amplify the difference between two conductors.
Note: the noise spikes appear on both the center conductor and the outer
shield and therefore are not amplified.
RCA Input
Differential
Input
cables and electrically-noisy environments make signal integrity
and noise rejection an extremely difficult challenge.
THE RESULT: Quiet transmission of audio from source to amplifier.
◆ NOMAD (NOn-Multiplying Advanced Decision)
The Power amplifiers use an
conditions. The innovative
technique ever used, bringing previously unavailable levels of accuracy, stability, temperature immunity and reliability to
this critical process. 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.
analog computer process
NOMAD
(NOn-Multiplying Advanced Decision) system is the most sophisticated version of this
to absolutely maximize safe output power under all operating
◆ MOSFET Devices (Metal Oxide Semiconductor Field Effect Transistor)
Rockford Fosgate is one of the few manufacturers in any of the sound communities to utilize MOSFET devices in both the
supply
and the
output stages. MOSFET
(Metal Oxide Semiconductor 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 linearity. In addition, MOSFET and vacuum tubes share
many important 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.
power
◆ ITS (Increased Thermal Stability)
The
ITS
(Increased Thermal Stability) Power Supply design is new in Rockford Fosgate amplifiers. A major problem
associated with any amplifier design is how to get rid of the heat generated by its circuitry. Clearly, it is highly desirable to
minimize the amount of heat generated in the first place. The “50 series” Power amplifiers employ a new toroidal power
transformer design in which the high current input leads are carried directly to the switching power MOSFETs. This both
minimizes PC board heating and takes advantage of natural air cooling of these leads.
THE RESULT: Maximizes power supply efficiency by eliminating unnecessary heat generation.
– 4 –
50.2 D
1.Cast Aluminum Chrome Heatsink – The cast aluminum heatsink of the Punch Power amplifier dissipates heat
2.End Caps – The unique end caps conceal the wiring and input cables, giving the amplifier a clean “stealth” look.
ESIGN
F
EATURES
generated by the amplifier's circuitry. The inherent advantage of casting provides a 30% improvement of cooling over
conventional extrusion heatsink designs.
3138
Unbal.
Speaker
0°-180°
+ L –
Gain
10
Power
REM
16
6
7
L (Mono)
R
Bal.
Pass-
LR
Thru
EZ - 180° - 0°Speaker
Bal.
Bridged
Input
9
Dual B+
5
44
Dual GND
312
+ R –
Gain
10
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 dual power and ground connectors on the Punch Power amplifier are gold-plated and will
accommodate up to two 8 AWG wires maximizing the input current capability of the amplifier.
5.REM Terminal – This gold-plated spade terminal is used for the AP (auto power) or remote turn-on of the Punch 50.2
Power amplifier.
6.RCA Input Jacks – The industry standard RCA jack provides an easy connection for signal level input. They are goldplated to resist the signal degradation caused by corrosion.
7.Balanced Line Input– This input will allow the balanced inputs to be used in conjunction with the Punch 50.2 Power
amplifier to provide better noise rejection.
8.Signal Input Switch – This switch allows selection of either the RCA or Balanced Line inputs.
9.RCA Pass-Thru Jacks – The Pass-Thru provides a convenient source for daisychaining an additional amplifier. This
eliminates the need for additional RCA cables or “Y” adapters. One of the internal crossovers can be designated to
the Pass Thru output creating a dedicated low-pass, high-pass, or full range output.
– 5 –
10.Input Sensitivity Controls – The input level controls are preset to match the output of most source units. They can
POWER
50.
2
Low-Pass
Full Range
High-Pass
HP
LP
HP
LP
FULL
XCard Options
XCard 1
XCard 2
Amplifier
Pass Thru
Amplifier
Amplifier
XCard 1XCard 2
ROCKFORD CORPORATION
MADE IN THE USA
®
25 Watts X 2 into 4 Ohms
with less than 0.05% THD + N from 20-20kHz
50 Watts X 2 into 2 Ohms
with less than 0.10% THD + N from 20-20kHz
®
AMPLIFIER
XCard 1XCard 2
XCard 1XCard 2
Audiophile Bypass
Not UsedNot Used
Audiophile Bypass
Not Used
Amp Only
Pass Thru
XCard 1
XCard 2
11
14
&
15
be adjusted to match output levels from a variety of source units.
11.Internal Crossovers – These built-in crossover cards are configurable for a multitude of operating frequencies. The
orientation of the card in its socket determines its function of high-pass, low-pass or full range operation.
12.E-Z Bridge Switch / 0°-180° Phase Switch – This dual purpose switch enables you to E-Z bridge the amplifier or
invert the signal phase of the right channel.
13.Phase Switch – This switch enables you to easily invert the phase of the left channel without having to disconnect
the speaker wires.
14.Crossover Switching – These internal switches allow the crossover to be distributed to the amplifier and Pass-Thru
in many different configurations.
15.Audiophile Bypass – One of the crossover switching configurations allows the internal crossover circuit to be
bypassed, maintaining Audiophile sound quality due to a shorter signal path.
16.LED Power Indicator – The LED gives a visual indication of the status of the amplifier, lighting when the unit is turned
on.
– 6 –
50.1 D
1.Cast Aluminum Chrome Heatsink – The cast aluminum heatsink of the Punch Power amplifier dissipates heat
2.End Caps – The unique end caps conceal the wiring and input cables, giving the amplifier a clean “stealth” look.
ESIGN
F
EATURES
generated by the amplifier's circuitry. The inherent advantage of casting provides a 30% improvement of cooling over
conventional extrusion heatsink designs.
L (Mono) R
Speaker
+ L –
L Pass-Thru R Pass-Thru
3
8
REM
544
9
Gain
Dual B+
136
Power
7
L + R / L
(Mono)
Dual GND
12
X-Over
24dB/12dB/0dB
11
0°-180°
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 dual power and ground connectors on the Punch Power amplifier are gold-plated and will
accommodate up to two 8 AWG wires maximizing the input current capability of the amplifier.
5.REM Terminal – This gold-plated spade terminal is used for the AP (auto power) or remote turn-on of the Punch 50.1
Power amplifier.
6.RCA Input Jacks – The industry standard RCA jack provides an easy connection for signal level input. They are goldplated to resist the signal degradation caused by corrosion.
7.Summed Stereo / Mono Switch – This switch is used to select whether 1 or 2 signal inputs will be used to drive the
amplifier.
8.Pass-Thru RCA Jacks – The Pass-Thru provides a convenient source for daisychaining an additional amplifier.This
eliminates the need for additional RCA cables or “Y” adapters. The Pass-Thru output is Full Range only.
9.Input Sensitivity Control – The input level control is preset to match the output of most source units. It can be adjusted
to match output levels from a variety of source units.
– 7 –
10.Internal Crossover – This built-in crossover card is configurable for a multitude of operating frequencies. The
ROCKFORD CORPORATION
MADE IN THE USA
®
High-Pass
HP
➝
➝
LP
Low-Pass
HP
➝
➝
LP
Full Range
FULL
↕
50.
1
®
AMPLIFIER
POWER
50 Watts X 1 into 4 Ohms
with less than 0.10% THD + N from 20-20kHz
100 Watts X 1 into 2 Ohms
with less than 0.15% THD + N from 20-20kHz
Do Not Chassis
Ground Any Speaker.
–
+
10
XCard 1
orientation of the card in its socket determines the function of high-pass, low-pass or full range operation.
11.Phase Switch – This switch enables you to easily invert the phase without having to disconnect the speaker wires.
12.Crossover Switch – This multi-function switch enables you to select a 12dB per octave slope or 24dB per octave
slope for the internal crossover. When switched to 0dB, the internal crossover circuit can be bypassed, maintaining
Audiophile sound quality due to a shorter signal path.
13.LED Power Indicator – The LED illuminates when the unit is turned on.
– 8 –
I
NSTALLATION
Tools Needed
The following is a list of tools you will need for installing the “50 Series” Power amplifiers:
Allen wrenches 9/64" & 3/32" (included)Wire Cutters
Wire strippersVoltmeter
Battery post wrenchWire crimpers
Electric hand drill and assorted bitsAssorted 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 on the layout of your new system, be sure that each component will be easily accessible for making
adjustments.
Before beginning any installation, be sure to follow these simple rules:
1. 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.
C
ONSIDERATIONS
4. Route all of the RCA cables close together and away from any high current wires.
5. Use high quality Connecting Punch accessories 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 for 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" (45.7cm) 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 connections should be as short as possible and always be connected to metal that is
welded to the main body, or chassis, of the vehicle.
– 9 –
M
OUNTING
The mounting location and position of your amplifier will have 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 conditions. 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.
Mounting the amplifier on the floor of the trunk will work but provides 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
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.
L
OCATIONS
not
recommended.
Mounting the amplifier with less than 1" (2.54cm) of air gap around the heatsink in the passenger compartment will not
provide proper cooling and will severely affect the performance of the amplifier and is strongly
Engine Compartment Mounting
Rockford Fosgate amplifiers should
but could create an embarrassing situation caused by the ridicule from your friends.
B
ATTERY AND
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 and an energy storage capacitor.
never
C
HARGING
not
recommended.
be mounted in the engine compartment. Not only will this void your warranty
– 10 –
W
IRING
T
HE
S
YSTEM
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. Configure the internal XCard crossovers prior to installation. Refer to the “Using the Signal Switching Network” (page
19 for the 50.2 and page 31 for 50.1) for further information.
2. Plan the wire routing. Take care when running signal level RCA cables to keep them close together but isolated 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.
3. 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. We recommend using (2) 8
gauge cables for power and for ground. This will give you the best
performance possible.
4. Strip 3/8" from the battery end of the power cable and crimp a large ring terminal to the cable. Use the ring terminal
to connect to the battery positive terminal. Do not install the fuse at this time.
5. Prepare a length of cable to be used for the ground connection. Strip 5/8" of insulation from the end of the cable as
described above and connect to the appropriate terminal of the amplifier. 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 non-anodized screw and a star washer.
6. Prepare the REM turn-on wire for connection to the amplifier by stripping 1/4" 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.
STRIP WIRE
AMP
>
><
5/8"
>
INSULATION
>
7. Securely mount the amplifier (with supplied screws) to the vehicle or amp rack. Be careful not to mount the amplifier
on cardboard or plastic panels. Doing so may enable the screws to pull out from the panel due to road vibrations or
sudden vehicle stops.
8. Connect the source signal to the amplifier by plugging the RCA cables into the input jack(s) at the amplifier. If using
Balanced Line Inputs, refer to page 24.
9. 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.
10. Perform a final check of the completed system wiring to 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.
DO NOT chassis ground any of the speaker leads as unstable operation may result.
– 11 –
11. 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 neighborhood. 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 successfully completed another upgrade to your audio system for which they will probably spill thumbtacks on your
driveway.
NOTICE!
U
SING
Amplifiers using the trans•
nova
topology improve in sound quality after
warming up. We recommend operating the 50.2 and 50.1 for approximately
15 minutes prior to evaluation under judging criteria or tune-ups to establish
its normal operating temperature.
* Your friends will call it MAGIC, you can call it Rockford technology! *
a
d
v
P
ASSIVE
C
ROSSOVERS
a
n
c
e
d
A passive crossover is a circuit that uses capacitors and/or coils and is placed on speaker leads between the amplifier and
speaker. The crossover delegates a specific range of frequencies to the speaker for optimum driver performance. A crossover
network can perform one of three functions: High-Pass (capacitors), Low-Pass (inductors or coils) and Bandpass
(combination of capacitor and coil).
The most commonly used passive crossover networks are 6dB/octave systems. These are easy to construct and require one
component per filter. Placing this filter in series with the circuit will reduce power to the speaker by 6dB/octave above or
below the crossover point depending on whether it is a high-pass or low-pass filter. More complex systems such as 12dB/
octave or 18dB/octave can cause impedance problems if not professionally designed.
Passive crossovers are directly dependent upon the speaker's impedance and component value for accuracy. When passive
crossover components are used in multiple speaker systems, the crossover's effect on the overall impedance should be taken
into consideration along with the speaker's impedance when determining amplifier loads.
For more information, see your Authorized Rockford Fosgate Dealer.
– 13 –
U
SING THE
The crossover functions are controlled through the use of an XCard and can be set for high-pass, low-pass or full range
operation. The XCard shipped with your amplifier is set for Full Range. 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.
XC
ARD
Low-PassFull RangeHigh-Pass
C
USTOMIZING THE
The crossover point can be altered by changing the 4 resistor values. Use the following formula to select the appropriate
resistor value to be placed on the XCard.
3386
7234
= R (in kΩ) for .047mf cap
f
o
= R (in kΩ) for .022mf cap
f
o
LP
➝
XC
HP
➝
ARD
➝
➝
HP
LP
The actual formula is: R =
Where: R = Ω
fo = desired crossover frequency
c = capacitor in farads
ex: .047 x 10-6 for .047mf cap
FULL
↕
a
O
p
d
e
v
r
a
a
n
t
c
i
e
o
d
n
1
2πfoc
Crossover Card
High Pass
R1
R2
Low Pass
Full Range
R1
FULL
R2
– 14 –
XC
ARD
R
ESISTOR
C
HART
Our tests have shown that using 0.047mf capacitors for frequencies below 100Hz, and 0.022mf capacitors for frequencies
above 100Hz, result in more linear crossover control. Refer to the Specifications page to determine the capacitor value of
each supplied XCard.
Butterworth Alignment Q = .707
1% resistors used with 0.047mF capacitors
Butterworth Alignment Q = .707
1% resistors used with 0.022mF capacitors