Rockford Fosgate AudioPhile LP-1 User manual

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AUDIO phile
LP-1 & LP-2 Low Pass Crossovers
2x-4 2-Way Crossover
Owner's Manual

Dear Customer,
Congratulations on your purchase of America’s finest
brandofCrossovers. AtRockfordFosgatewearecommit-
tedtomusicalreproductionatitsbest,andwearepleased
you chose our product. Through years of engineering
expertise, hand craftsmanship and critical testing proce-
dures 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 Au-
thorized Rockford Fosgate Dealer, as we provide special-
ized training through Rockford Technical Training Insti-
tute (RTTI). Please read your warranty and retain your
receipt and original carton for possible future use.

PRACTICE SAFE SOUND™
CONTINUOUSEXPOSURETOSOUNDPRESSURELEVELS
OVER 100dB MAY CAUSE PERMANENT HEARING LOSS.
HIGH POWERED AUTO SOUND SYSTEMS MAY PRODUCE
SOUNDPRESSURELEVELSWELLOVER130dB.USECOM-
MON SENSE AND PRACTICE SAFE SOUND.
Theserialnumbercanbefoundontheoutsideofthebox. Please
be sure to record it in the space provided below as your perma-
nentrecord. Thiswillbecomeusefulinrecoveringyourproduct
if ever stolen and serve as verification of your factory warranty.
Serial Number: _________________________________________
Model Number:___________________________________

Introduction
This manual provides information on the features, installa-
tion and operation of the Punch AUDIOphile Low Pass
Crossovers(LP-1andLP-2),and2-wayCrossover(2x-4). We
suggest you save this manual for future reference.
We strongly recommend you have your Authorized Rock-
ford Fosgate Dealer install the Crossovers. If you do choose
to install the crossover yourself, please be sure to read the
entire manual before beginning.
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Design & Features
Punch Audiophile LP1 and LP2
The Punch AUDIOphile LP-1 and LP-2 passive, two channel,
low pass crossovers are designed to conform to the perfor-
manceandstandardsofthenewPunchAUDIOphilewoofers,
but will work with all Rockford Fosgate woofers. These low
pass filters are designed to meet the following criteria:
• Firstordernetwork(s),6dB/octaveat100Hzfor2Ω/4Ωloads
• Compactdesignwithscrewterminalsforinputandoutput
• 200 watt power handling
• Low DC resistance to minimize losses
• Two channel or single channel operation
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Punch AUDIOphile 2x-4
The 2x-4 Crossover is designed to be the "link" between
tweeters, and mid-bass and mid-range speakers. This com-
pact2-waycrossoverisdesignedtoconformtothefollowing
criteria:
• 2-Way Crossover network centered at 4kHz
• Uses Linkwitz-Riley 2nd order transfer function (12dB/
octave)
• Additional tweeter filtering uses a series notch filter cen-
tered at 1500Hz to minimize the tweeter's resonant peak
• Also included is an impedance compensation network
(Zobel)that flattens outthe gradual impedancerise above
10kHz
• Tweeter protection provided through a special compres-
sion circuit
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The compression circuit in the crossover consists of an
array of two lamps wired in parallel, whose function is to
monitor the input power to the tweeter. When it sees a
threatening increase in input voltage, it will increase its
resistance. This technique is fast, and virtually undetect-
able to the listener. Other manufacturers' tweeter protec-
tion is done via circuit breakers, which drastically reduce
tweeter output – very noticeable and distracting for the
listener.
• Smallsize,accomplishedbyinductorswoundonspecially
designed ferrite bobbins
Note: With the second order Linkwitz-Riley network of the
2x-4, an out-of-phase condition can exist in the pass band.
The best performance is usually achieved by placing the
tweeter out-of-polarity with the midrange/woofer. We rec-
ommend you start with it wired in this manner, listen,
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reverse the polarity, and then listen again. Select the one
which offers the smoothest sounding frequency response.
See the wiring diagrams on pages 12 and 13 for more
information.
Mounting the Crossovers
TheLP-1,LP-2,and2x-4aresecuredtorelativelyflatsurfaces
withsheetmetalscrewsinsertedinto the mounting holeson
either side of the enclosure.
Input & Output Connectors
The LP-1, LP-2, and 2x-4 feature silver-plated “screw-lok”
terminalswhichareusedtosecureboththeinputandoutput
speaker wires. The LP-1 and LP-2 accept wire sizes up to 12
gauge.

Wiring the Crossovers
TheLP-1 and LP-2aredesigned to be wiredinseries with the
subwoofers being used. Both positive (+) and negative (-)
thruputconnectorsareprovided. Formoreinformation,refer
to the diagrams beginning on page 8.
Working with 2Ωand 4Ωwoofer loads and crossover fre-
quencies of 100Hz will set the inductor values for the LP-1
and LP-2 at 3.5 mH and 6.6 mH respectively.
To place the crossover in “mono mode,”
1. Placea jumperbetween theleft toright positiveoutputs.
2. Place another jumper between the left to right negative
outputs.
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Oncethe jumpers are in place,mono filterinput and output
then become either the left positive (+) and negative (-), or
right positive (+) and negative (-) inputs.
The table below lists the various crossover options available
withtheLP-1andLP-2filters. Thefrequenciesindicatedhere
reflect real measurements and not calculations based on
inductor values.
Model Number 2
Ω Load 4 Ω Load 8 Ω Load
LP-1 Stereo Mode 100 Hz 200 Hz 400 Hz
LP-1 Mono Mode 50 Hz 100 Hz 200 Hz
LP-2 Stereo Mode 50 Hz 100 Hz 200 Hz
LP-2 Mono Mode 25 Hz 50 Hz 100 Hz
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