Rockford Fosgate Punch 250.2 User manual

punch
competition Power amplifiers
Operation & Installation
250. 1
250. 2
® ®
car audio
fanatics
for
®
power
power
new
chrome
heatsink

Dear Customer,
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). Pleasereadyourwarrantyandretainyourreceiptandoriginalcartonforpossiblefutureuse.
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.
TogetafreebrochureonRockfordFosgateproductsandRockfordwearables,pleasecall602-967-3565orFAX
602-967-8132. For International orders, 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.Ifyou needfurtherassistance,you cancallus directat1-800-669-9899.Be suretohaveyour serialnumber,modelnumber
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.

T ABLE OF C ONTENTS
Introduction.................................................................................................................................................................1
Punch Accessory Pack .................................................................................................................................................1
Technical Design Features.............................................................................................................................................2
250.2Design Features .................................................................................................................................................5
250.1Design Features .................................................................................................................................................7
Installation Considerations ............................................................................................................................................9
Mounting Locations....................................................................................................................................................10
Battery and Charging .................................................................................................................................................10
Wiring the System......................................................................................................................................................11
Using Passive Crossovers............................................................................................................................................12
Table of Crossover Components...................................................................................................................................13
Using the XCard.........................................................................................................................................................14
Customizing the XCard ...............................................................................................................................................14
XCard Resistor Chart...................................................................................................................................................15
250.2Installation ......................................................................................................................................................16
Using the 250.2Internal Switching Network ..................................................................................................................19
Using the 250.2Balanced Line Inputs ..........................................................................................................................24
250.1Installation ......................................................................................................................................................26
Using the 250.1Internal Switching Network ..................................................................................................................31
System Diagrams.......................................................................................................................................................34
Rockford Fosgate Accessories ......................................................................................................................................38
Troubleshooting.........................................................................................................................................................40
Autosound 2000’s Quick Check for Troubleshooting.......................................................................................................43
250.2Specifications...................................................................................................................................................46
250.1Specifications ..................................................................................................................................................47
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,
haveworked veryhard tomake sureallthe informationin thismanual iscurrent. But,as weareconstantly findingnew ways
to improve our product, this information is subject to change without notice.
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Sections marked
ADVANCED
OPERATION
include in-depth
technical information
Sections marked
INSTALLATION
include “slam dunk”
wiring connections
Sections marked
TROUBLESHOOTING
include recommendations
for curing installation
problems
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– 1 –
P UNCH A MPLIFIER A CCESSORY P ACK
The accessory pack shipped with the “250 series” Power amplifiers include the mounting hardware necessary to secure
the ampliifer to the vehicle and to attach the end caps to the amplifier.
Punch Power 250.2 Punch Power 250.1
Installation & Operation Manual Installation & Operation Manual
Punch Verification Certificate Punch 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"
The“250Series”Poweramplifiers representthebestRockfordFosgatehastooffer! Ourengineersdevisedtechnicalfeatures
whichwouldbeconsideredoverkillbyotheraudiomanufacturers, butnotatRockfordFosgate!Trans•nova,DIAMONDand
TOPAZ, exclusively designed by Rockford, are just a few of these features which are described in the Technical Design
Features section of this manual.
The250.2isa two-channel amplifier whichisoptimizedtodrive2Ωstereoand4Ωbridgedloads.The250.1 is a single
channel amplifier optimized to drive a 2Ω(single amp) or a 4Ωbridged load (pair of amps bridged to a single load).
The“250 series” useRockford's innovative technologiesfor awesomesound quality, reliableperformance andhigh output
power into low impedances. This can be beneficial for serious competition vehicles.
I NTRODUCTION TO 250 S ERIES

– 2 –
T ECHNICAL D ESIGN F EATURES
Many of the solutions to common design problems encountered by Rockford Fosgate engineers created entire new circuit
designsaswellasnewwaystoconstructthePunch250.2and250.1PowerAmplifiers.Inourflagshipamplifiers,noexpense
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.
◆trans• nova (TRANSconductance NOdal Voltage Amplifier)
The trans• nova (TRANS conductance NOdal Voltage Amplifier) is a patented circuit (U.S. Patent 4,467,288) that allows
the audio signal to pass through the amplifier at low voltage . Each amplifier channel utilizes its own “fully floating” power
supply and is configured to increase power gain. The increase in power gain allows the drive stage to operate at a lower
voltage.Alow voltagedrivestageis thesameprinciple usedinhighquality preamplifierstoproducehigh linearityandwide
bandwidth.
E-I I-E
trans•nova circuitry
The resulting design utilizes an output stage with a simpler gain structure and a shorter total signal path than conventional
highvoltage(bi-polar)designs.Thenumberofstagesisreducedfromfiveormoretothree.Theoutputstageisfurtherrefined
intoatrans-impedancestage(currenttovoltageconverter)toachieveashortloop(fast)negativefeedback.Theoutputstage
is driven cooperatively by a transconductance stage (voltage to current converter).
THE RESULT: Superior sound quality, greater efficiency and higher reliability.
◆DIAMOND (Dynamically Invariant AMPlification Optimized Nodal Drive)
DIAMOND (DynamicallyInvariantAMplificationOptimizedNodalDrive-patentpending)isanimportantadvanceincircuit
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
highfrequencydistortionbyallowingthedrivertooperatewith20dBormoreofcurrentheadroom,whereastraditionaldrivers
have only 6dB of current headroom.
THE RESULT: Lower distortion and greater inherent stability.
◆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
powersupplygroundoftheamplifier.Thisisaccomplishedbyallowingthesourceunittocontrolthepotential“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.

– 3 –
◆DSM (Discrete Surface Mount Technology)
The DSM (Discrete Surface Mount) manufacturing process combines the advantages of both discrete components and
integratedcircuitry.RockfordFosgateistheonlyAmericanamplifiermanufacturertohaveinvestedmillionsintothisprocess.
DSM components differ from conventional discrete components in different ways. They are more compact, more rugged,
andtheyefficientlydissipategeneratedheat.Usingthemwhereverappropriateallowstheadvantagesassociatedwithdiscrete
circuitry to be retained while also providing room for both highly advanced processing features and generous PC board
copperpathswhere needed.Theirshort lead-outstructuresallowmaximum audioperformanceand highestsignal-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.
Figure 1
Thru-Hole Surface Mount
Component
Solder Solder
PC Board PC Board
THERESULT:Lessconnections,improvedreliability,shortersignalpaths,superiorsignal-to-noiseratioandawesomesonic
performance.
◆XCard (Internal Crossover)
ThePoweramplifiersutilizeinternalactivecrossovers.Thesecrossovershavemanyperformanceadvantagessuchasusing
discrete components for exact frequency adjustments which are far superior to potentiometers. Additionally, the XCard can
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.
◆Stereo Pass-Thru
The Pass-Thru outputprovidesaconvenientsourcefordaisy-chaininganadditionalamplifierwithouttheneedforextraRCA
cablesor“Y”adapters.The250.1Pass-ThruprovidesconstantFullRangestereooutput.The250.2hastheabilitytoprovide
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.

– 4 –
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.
Center
Conductor
Outer
Shield
RCA Input Differential
Input
Figure 2
◆Balanced Line Inputs (250.2)
Using the Balanced Line Inputs provides the last word in achiev-
able 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. Bal-
anced line is universal in concert installations where the stage
and mixing consoles are hundreds of feet apart. Long signal
cablesandelectrically-noisyenvironments makesignalintegrity
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 analog computer process to absolutely maximize safe output power under all operating
conditions. 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 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.
◆MOSFET Devices (Metal Oxide Semiconductor Field Effect Transistor)
RockfordFosgateisoneofthefewmanufacturersinanyofthesoundcommunitiestoutilizeMOSFETdevicesinboththe power
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.
◆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 “250 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.

250.2D ESIGN F EATURES
1. Cast Aluminum Chrome Heatsink – The cast aluminum heatsink of the Punch Power amplifier dissipates heat
generatedbytheamplifier'scircuitry.Theinherentadvantageofcastingprovidesa30%improvementofcoolingover
conventional extrusion heatsink designs.
2. End Caps – The unique end caps conceal the wiring and input cables, giving the amplifier a clean “stealth” look.
– 5 –
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. REMTerminal–Thisgold-platedspadeterminalisusedfortheAP(autopower)orremoteturnonofthePunch250.2
Power amplifier.
6. RCA Input Jacks– The industrystandardRCAjackprovidesan easyconnectionforsignallevelinput. They aregold-
plated to resist the signal degradation caused by corrosion.
7. BalancedLineInput–Thisinputwillallowthebalancedinputs tobeusedinconjunctionwiththePunch250.2Power
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 – ThePass-Thru providesa convenient sourcefor daisychainingan additionalamplifier. 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.
Speaker
+ L –
16 54 4
3 13 8
10
6
9
7
10
312
0°-180°Bal.
Unbal.
Gain
L (Mono) R
LR
Pass-
Thru Gain
EZ - 180°- 0°Speaker
+ R –
Bal.
Input Bridged
Power
REM Dual B+ Dual GND

10. Input Sensitivity Controls – The input level controls are preset to match the output of most source units. They can 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-ZBridgeSwitch/0°-180°PhaseSwitch–ThisdualpurposeswitchenablesyoutoE-Zbridgetheamplifierorinvert
the signal phase of the right channel.
13. Phase Switch – Thisswitch enables youto easilyinvert the phaseof theleft channelwithout having todisconnect 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. AudiophileBypass–Oneofthecrossoverswitchingconfigurationsallowstheinternalcrossovercircuittobebypassed,
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 –
Low-Pass
Full Range
High-Pass
HP
LP
HP
LP
FULL
*Bridging Note: The Punch 250.
2
can be
bridged in many configurations. Refer to your
owner's manual to determine which mode will
work best in your system.
125 Watts X 2 into 4 Ohms
with less than 0.05% THD + N from 20-20kHz
225 Watts X 2 into 2 Ohms
with less than 0.10% THD + N from 20-20kHz
ROCKFORD CORPORATION
MADE IN THE USA
®
XCard Options
XCard 1 XCard 2
Amplifier Pass Thru
Amplifier Amplifier
XCard 1 XCard 2
250.
2
®
AMPLIFIER
POWER
XCard 1 XCard 2
XCard 1 XCard 2
Audiophile Bypass
Not Used Not Used
Audiophile Bypass
Not Used
Amp Only
Pass Thru
XCard 1
11
XCard 2
14
&
15

250.1D ESIGN F EATURES
1. Cast Aluminum Chrome Heatsink – The cast aluminum heatsink of the Punch Power amplifier dissipates heat
generatedbytheamplifier'scircuitry.Theinherentadvantageofcastingprovidesa30%improvementofcoolingover
conventional extrusion heatsink designs.
2. End Caps – The unique end caps conceal the wiring and input cables, giving the amplifier a clean “stealth” look.
– 7 –
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. REMTerminal–Thisgold-platedspadeterminalisusedfortheAP(autopower)orremoteturnonofthePunch250.1
Power amplifier.
6. RCAInput Jacks–TheindustrystandardRCAjackprovidesaneasyconnectionforsignallevelinput.Theyaregold-
plated 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. InputSensitivityControl–Theinputlevelcontrolispresettomatchtheoutputofmostsourceunits.Itcanbeadjusted
to match output levels from a variety of source units.
Speaker
+ L –
5 4 4
136
3
9711
12
X-Over
24dB/12dB/0dB 0°-180°
REM Dual B+ Dual GND
L + R / L
(Mono)
Gain
Power
8
L (Mono) R
L Pass-Thru R Pass-Thru

10. Internal Crossover – This built-in crossover card is 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.
11. PhaseSwitch–Thisswitchenablesyoutoeasilyinvertthephasewithouthavingtodisconnectthe speakerwires.
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 –
HP
LP
HP
LP
FULL
ROCKFORD CORPORATION
MADE IN THE USA
®
Do Not Chassis
Ground Any Speaker.
–+
POWER
®
250 Watts X 1 into 4 Ohms
with less than 0.10% THD + N from 20-20kHz
500 Watts X 1 into 2 Ohms
with less than 0.15% THD + N from 20-20kHz
AMPLIFIER
250.
1
10
XCard 1
Low-Pass
Full Range
High-Pass

– 9 –
I NSTALLATION C ONSIDERATIONS
Tools Needed
The following is a list of tools you will need for installing the “250 Series” Power amplifiers:
Allen wrenches 9/64" & 3/32" (included) Wire Cutters
Wire strippers Voltmeter
Battery post wrench Wire crimpers
Electric hand drill and assorted bits 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 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.
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.

M OUNTING L OCATIONS
The mounting location and position of your amplifier will have a great effect on its ability to dissipate the heat generated
undernormaloperation.Thedesignofourcastaluminumheatsinkservestoeasilydissipatetheheatgeneratedoverawide
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.
Mountingtheamplifieronthefloorofthetrunkwillworkbutprovideslesscoolingcapabilitythanverticalmounting.
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 heatsink in the passenger compartment will not
provide proper cooling and will severely affect the performance of the 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.
– 10 –
B ATTERY AND C HARGING
Amplifierswillputanincreasedloadonthevehicle'sbatteryandchargingsystem. Werecommendcheckingyouralternator
and battery condition to ensure that the electrical system has enough capacity to handle the increased load of your stereo
system.Stockelectricalsystemswhichareingoodconditionshouldbeableto handletheextraloadofanyRockfordamplifier
withoutproblems,althoughbatteryandalternatorlifecanbereducedslightly.TomaximizetheperformanceofyourRockford
Fosgate amplifier, we suggest the use of a heavy duty battery and an energy storage capacitor.
NOTE: These amplifiers utilize a large array of power supply capacitance and can draw substantial current at turn-
on. The dashboard BATTERY VOLTAGE and/or ALTERNATOR CHARGE lamp may illuminate for a brief period while
momentarily recharging the capacitor bank. This may be most noticeable when the amplifier is off for at least a day
or two and is considered normal operation.

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 250.2 and page 31 for 250.1) 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"
ofinsulation from theend ofthe wire.The useof 8 gaugepower cablecan
interferewiththeinstallationoftheendcaps.Properwiredresscanprevent
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
paintfromthemetalsurfaceandthoroughlycleantheareaofalldirtandgrease.Striptheotherendofthewireandattach
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
theotherend oftheREMwire toaswitched12volt positivesource.Theswitched signalisusuallytaken fromthesource
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.
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. DO NOT chassis ground any of the speaker leads as unstable operation may result.
– 11 –
><
5/8"
INSULATION
STRIP WIRE
>
>
AMP
>

U SING P ASSIVE C ROSSOVERS
A passive crossover is a circuit that uses capacitors and/or coils and is placed on speaker leads between the amplifier and
speaker.Thecrossoverdelegatesaspecificrangeoffrequenciestothespeakerforoptimumdriverperformance.Acrossover
network can perform one of three functions: High-Pass (capacitors), Low-Pass (inductors or coils) and Bandpass
(combination of capacitor and coil).
Themostcommonlyusedpassivecrossovernetworksare6dB/octavesystems.Theseareeasytoconstructandrequireone
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.
Passivecrossoversaredirectlydependentuponthespeaker'simpedanceandcomponentvalueforaccuracy.Whenpassive
crossovercomponentsareusedinmultiplespeakersystems,thecrossover'seffectontheoverallimpedanceshouldbetaken
into consideration along with the speaker's impedance when determining amplifier loads.
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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.
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
justsuccessfullycompletedanotherupgradetoyouraudiosystemforwhichtheywillprobablyspillthumbtacksonyour
driveway.
– 12 –
NOTICE!
Amplifiers using the trans• nova topology improve in sound quality after
warming up. We recommend operating the 250.2and 250.1for approximately
15minutespriortoevaluationunder judgingcriteriaortune-upstoestablishits
normal operating temperature.
* Your friends will call it MAGIC, you can call it Rockford technology! *

T ABLE OF C ROSSOVER C OMPONENT V ALUES
6dB/Octave Low-Pass 6dB/Octave High-Pass
Freq.
Hertz Speaker Impedance
80 4.1mH 1000µF 8.2mH 500µF 16mH 250µF
100 3.1mH 800µF 6.2mH 400µF 12mH 200µF
130 2.4mH 600µF 4.7mH 300µF 10mH 150µF
200 1.6mH 400µF 3.3mH 200µF 6.8mH 100µF
260 1.2mH 300µF 2.4mH 150µF 4.7mH 75µF
400 .8mH 200µF 1.6mH 100µF 3.3mH 50µF
600 .5mH 136µF 1.0mH 68µF 2.0mH 33µF
800 .41mH 100µF .82mH 50µF 1.6mH 26µF
1000 .31mH 78µF .62mH 39µF 1.2mH 20µF
1200 .25mH 66µF .51mH 33µF 1.0mH 16µF
1800 .16mH 44µF .33mH 22µF .68mH 10µF
4000 .08mH 20µF .16mH 10µF .33mH 5µF
6000 51µH14µF .10mH 6.8µF .20mH 3.3µF
9000 34µH 9.5µF68µH 4.7µF .15mH 2.2µF
12000 25µH 6.6µF51µH 3.3µF 100µH 1.6µF
2 OHMS 8 OHMS
4 OHMS
LC L CL C
LC
L = Low-Pass (Inductor)
C = High-Pass (Capacitor)
For more information, see your Authorized Rockford Fosgate Dealer.
6dB/Octave High-Pass and Low-Pass Filters
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– 13 –

U SING THE XC ARD
The crossover functions are controlled through the use of an XCard and can be set for high-pass, low-pass or full range
operation.TheXCard shippedwithyour amplifierisset forFullRange. Eachcrossovercard hastwofaces: onefaceoperates
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.
C USTOMIZING THE XC ARD
7234
fo
3386
fo= R (in kΩ) for .047mf cap
= R(in kΩ) for .022mf cap
1
2πfoc
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.
Low-Pass Full RangeHigh-Pass
FULL
↕
HP
➝
➝
LP
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
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– 14 –
Crossover Card
High Pass
Low Pass
Full Range
R1 R2 R1 R2
FULL

– 15 –
XC ARD R ESISTOR C HART
Frequency R1 R2
20Hz 169kΩ169kΩ
25Hz 133kΩ133kΩ
30Hz 110kΩ110kΩ
35Hz 95.3kΩ95.3kΩ
40Hz 84.5kΩ84.5kΩ
45Hz 75kΩ75kΩ
50Hz 68.1kΩ68.1kΩ
55Hz 61.9kΩ61.9kΩ
60Hz 56.2kΩ56.2kΩ
65Hz 52.3kΩ52.3kΩ
70Hz 48.7kΩ48.7kΩ
75Hz 45.3kΩ45.3kΩ
80Hz 42.2kΩ42.2kΩ
85Hz 40.2kΩ40.2kΩ
90Hz 37.4kΩ37.4kΩ
200Hz 16.9kΩ16.9kΩ
300Hz 11.3kΩ11.3kΩ
400Hz 8.45kΩ8.45kΩ
500Hz 6.65kΩ6.65kΩ
600Hz 5.62kΩ5.62kΩ
700Hz 4.75kΩ4.75kΩ
800Hz 4.22kΩ4.22kΩ
900Hz 3.74kΩ3.74kΩ
1.0kHz 3.40kΩ3.40kΩ
1.2kHz 2.80kΩ2.80kΩ
2kHz 1.69kΩ1.69kΩ
3kHz 1.10kΩ1.10kΩ
4kHz 845Ω845Ω
5kHz 665Ω665Ω
6kHz 562Ω562Ω
7kHz 487Ω487Ω
8kHz 422Ω422Ω
Butterworth Alignment Q = .707
1% resistors used with 0.047mF capacitors
Frequency R1 R2
20Hz 357kΩ357kΩ
25Hz 287kΩ287kΩ
30Hz 237kΩ237kΩ
35Hz 205kΩ205kΩ
40Hz 178kΩ178kΩ
45Hz 162kΩ162kΩ
50Hz 143kΩ143kΩ
55Hz 130kΩ130kΩ
60Hz 121kΩ121kΩ
65Hz 110kΩ110kΩ
70Hz 102kΩ102kΩ
75Hz 95.3kΩ95.3kΩ
80Hz 90.9kΩ90.9kΩ
85Hz 84.5kΩ84.5kΩ
90Hz 80.6kΩ80.6kΩ
200Hz 35.7kΩ35.7kΩ
300Hz 23.7kΩ23.7kΩ
400Hz 17.8kΩ17.8kΩ
500Hz 14.3kΩ14.3kΩ
600Hz 12.1kΩ12.1kΩ
700Hz 10.2kΩ10.2kΩ
800Hz 9.9kΩ9.9kΩ
900Hz 86kΩ86kΩ
1.0kHz 7.15kΩ7.15kΩ
1.2kHz 6.04kΩ6.04kΩ
2.0kHz 3.57kΩ3.57kΩ
3.0kHz 2.37kΩ2.37kΩ
4.0kHz 1.76kΩ1.76kΩ
5.0kHz 1.43kΩ1.43kΩ
6.0kHz 1.21kΩ1.21kΩ
7.0kHz 10.2kΩ10.2kΩ
8.0kHz 909Ω909Ω
Butterworth Alignment Q = .707
1% resistors used with 0.022mF capacitors
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Ourtestshaveshownthatusing0.047µfcapacitorsforfrequenciesbelow100Hz,and0.022mfcapacitorsforfrequencies
above 100Hz, result in more linear crossover control. Refer to the Specifications page to determine the capacitor value
of each supplied XCard.

250.2I NSTALLATION
– 16 –
*Keep wire as short as possible.
250.2Power Connections (Option #1)
250.2Power Connections (Option #2)
*Keep wire as short as possible.
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® ®
REM
Power
Connect to remote
turn-on lead of
source unit.
Connect to B+ of battery
with a 60 amp fuse.
Connect to chassis
ground of vehicle*
Dual B+ Dual GND
Less than 18"
+ –
1.0
®
the connecting
® ®
1 farad • 20 VDC • 95°C
1.0
cap
punch
REM
Power
Connect to remote
turn-on lead of
source unit.
Connect to B+ of battery
with a 60 amp fuse.
Connect to chassis
ground of vehicle*
Dual B+ Dual GND
Less than 18"
+ –
Optional energy
storage capacitor

– 17 –
•RCA inputs are connected to both left and right channels
•Signal Input Switch selected to
Unbalanced for RCA input
•Left Phase Switch set to
0°
• Right Phase Switch set to 180° for stereo/mono operation
• All speaker polarity on right channel is inverted to correct for signal phase
•Gain for left and right channels set
equally to balance the subwoofer
•Impedance for
each channel should be 2Ωminimum
•Impedance for bridged channel should be 4Ωminimum
•XCard is in Full Range position
•Passive crossovers are needed for proper stereo/mono operation
•RCA inputs are connected to both
left and right channels
•Signal Input Switch selected to
Unbalanced for RCA input
•Left Phase Switch set to
0°
•Right Phase Switch set to 0°
•Gain for left and right channels operate independently
•Impedance for each channel should be 2Ωminimum
•XCard can be High-Pass, Low-Pass or Full Range position
Stereo/Mono Operation
Stereo Operation
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R
Unbal.
Pass
Thru
Bal.
Input
L
0°-180°EZ-180°-0°
Bridged
Gain
Bal.
Gain
–
+
RCA
Input
+
–
4Ωmin.
+–
+
Speaker
Terminal
–
Speaker
Terminal
Speaker
+ L – Speaker – R +
L (Mono) R
2Ωmin. 2Ωmin.
R
Unbal.
Pass
Thru
Bal.
Input
L
0°-180°EZ-180°-0°
Bridged
Gain
Bal.
Gain
–
+
RCA
Input
+
–
Speaker
+ L –
L (Mono)
Speaker
– R +
R
2ΩMin. 2ΩMin.