Rockford Fosgate 250.2 manual Time for Processors, Monthly magazine for the technically inclined

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III.MOVE THE DECK. If you're at this step, it's time to turn your system into an “amplified deck” by temporarily relocating the deck right ON TOP of the clean amplifier. Then using very, very short signal cables, connect the output of the deck into the input of the amp and test for noise. Play a zero bit track – silence – and make sure all is completely quiet.

A.If still noisy, you're in a heap of trouble. We suggest that you try another deck and give us a call so that we can put your name into the record books. It's a bad car audio day for you.

B.If the deck is quiet, then congratulations, you're on your way to a successful installation. It is now time to slowly, methodi- cally, reinstall the deck back into its final position. Test for noise each step of the way. If the noise returns, suspect the signal cables. Forget shielding because it will have only a very, minimal effect within the audio band. We highly suggest using twisted pair cables or a balanced transmission system for cable induced noise.

Time for Processors:

By the end of Step III, you should have the deck playing quietly with the amp, with the quiet cables quietly routed. So it's time to add the signal processors – one at a time – back into the system. Simply repeat Steps II and III with the equalizer, then the electronic crossover, etc. However, before MOVING THE SIGNAL PROCESSORS to the amplifier, we highly suggest that you power the noisy process from an isolated power supply rather than the car's +12 volts DC and chassis ground. Make sure to also connect the turn- on lead to the isolated power supply. If the processor is now quiet, then it is highly probable that the component has inadequate isolation. Solutions include changing components or permanently adding an external isolated power supply (Call Autosound 2000 at 209-465-3450 for info on isolated power supplies).

Summation:

During the design stage of your vehicles, try to avoid using extra batteries and high output alternators. Extra batteries are nothing but loads as soon as the engine is started and high output alternators usually make more noise than stock alternators. Also, extra batteries installed in the trunk of a car will ALWAYS force extra ripple current to flow over the car.

Install Stiffening Capacitors® as close to the power supply input of your amplifier as possible. The big caps will feed the switching power supplies of your amps and minimize the inductive losses in your power wiring. Plus, they will help your peak system response.

In problem cases, we highly recommend the use of twisted pair cable rather than coaxial cable for RCA leads. This practice will greatly minimize cable induced noise – especially in four channel amps!

Don't forget that your system is only as good as its worst component. Do NOT use components with inadequate power supply isolation or you will be asking for problems.

The best electrical ground on a car is the CHASSIS of the car. Do NOT run ground leads up to the case of the alternator or the negative battery post. Keep ALL ground leads as short as possible.

With properly isolated components, it does NOT matter where the component is grounded. We're sorry to say that with inadequately isolated components, it matters! With poorly isolated components, different grounds can cause different noises.

The deck is the signal reference ground for the entire sound system. The deck usually has THREE connections to the car's chassis: The black ground lead, the base of the antenna, and the metal-to-metal bond between the case of the deck and the chassis of the car. With three grounds, there is usually NO cause to worry about the ground of a deck.

Amplifiers are usually designed with adequate power supply isolation. This means that it should not matter where a deck is grounded. (Decks are grounded three times and amps float. This is car audio!)

The more components installed on a signal path, the more chances for noise to enter a system. The more electrical accessories on a car, the more noise will be produced by the alternator.

This information was compiled from more than 20 years of working in car audio. If you would like more information on this topic, or any other technical aspects of car audio, please call 800-548-8200 and ask for a subscription to Autosound 2000 Tech Briefs

— the monthly magazine for the technically inclined.

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Contents Punch Serial Number Model Number Practice Safe SoundT T I N G S TA R T E D Table of ContentsIntroduction to 250 Series Punch Amplifier Accessory PackTransnova TRANSconductance NOdal Voltage Amplifier Technical Design FeaturesStereo Pass-Thru Result Quiet transmission of audio from source to amplifier Balanced Line InputsDesign Features 250 Mono 1AMPLIFIER Tools Needed Installation ConsiderationsMounting Location S Battery and ChargingWiring the System Using Passive Crossovers 6dB/Octave High-Pass and Low-Pass Filters Table of Crossover Component Values7234 Using the XcardCustomizing the Xcard 3386Xcard Resistor Chart Power Connections Option #2 InstallationPower Connections Option #1 Stereo/Mono Operation Stereo OperationEZ-Bridged Operation Bridged OperationAmplifier Using the 250.2 Signal Switching NetworkXCard not required Uses output from XCard Pass-Thruuses output from XCard Pass Thru XCard Audiophile Bypass the Pass-Thru Connecting the BLT Using the 250.2 Balanced Line InputsAC Voltmeter set to AC Volts Disconnect Speakers fromKeep ground connections as close to each other as possible Mono Operation 250 #1 250 #2 Stereo Operation using two Punch 250.1 Power AmplifiersXCard 250.1 #1/#2 set to Full Range Bridged Mono Operation Audiophile Bypass US I N G T H E 250.1 Signal SW I T C H I N G NE T W O R KXover is set to 12dB Pass-Thruhas Full Range output only Configure a 12dB per octave filter forConfigure a 24dB per octave filter for the 250 Watt System rated @ 4 ohms System DiagramsTotal Power Delivery RMS 12dB/octave BP Woofers12dB/octave HP Total Power Delivery RMS Tweeters 450 Balanced Line Transmitter FG-BLT Rockford Fosgate AccessoriesRecommended capacitance is 1 farad per 1000 watts Energy Storage CapacitorsXCard Crossovers Amplifier has no sound TroubleshootingSymptom Diagnosis Remedy Amplifier does not turn onNo output from Pass-Thru Speaker Output LowOr Distorted Amplifier NoiseRepair or replace original source as Needed Source unit output too lowAutosound 2000s Quick Check for Troubleshooting CAR Audio SystemsMonthly magazine for the technically inclined Time for ProcessorsDynamic Power Measurements Watts Specifications500 Watts 420 Watts710 Watts 1420Limited Warranty Information R M a T I O N Ubicación DE LOS Amplificadores IntroducciónOperación mono/estéreo EspañolMontage IntroductionOpération stéréo/mono Tri- mode Einbauort EinleitungStereo/Mono Betrieb Linken Phasen Schalter auf 0 stellenTerminale GND cavo negativo IntroduzioneDove Posizionarlo Terminale B+ cavo positivoFase sinistra dellinterruttore posizionata su Stereo/Mono OperationMade in the USA

250.2 specifications

The Rockford Fosgate 250.2 is a powerful and versatile car amplifier known for its performance and reliability. As part of Rockford Fosgate’s renowned line of audio equipment, the 250.2 is engineered to enhance the listening experience in vehicles, providing a fantastic balance of power, clarity, and durability.

This amplifier delivers an impressive 250 watts of power, making it suitable for both beginner audiophiles and seasoned enthusiasts who seek to elevate their car audio system. The 250.2 is a two-channel amplifier, which means it can power two speakers or one subwoofer. Utilizing a class A/B topology, it ensures high efficiency while minimizing distortion, resulting in clean and powerful audio output.

One of the standout features of the Rockford Fosgate 250.2 is its Signal Sense turn-on technology. This feature allows the amplifier to automatically turn on when it detects a signal from the head unit, eliminating the need for a manual switch. Additionally, the built-in remote gain control allows users to adjust the amplifier’s output level easily, providing a customizable audio experience tailored to their preferences.

The 250.2 is equipped with an adjustable crossover that can be set to high-pass, low-pass, or full-range modes. This flexibility permits users to fine-tune the frequencies sent to their speakers, optimizing sound quality and performance. Further enhancing its capabilities, the amplifier also includes built-in variable bass boost that allows users to amplify low frequencies for a more impactful bass response.

Constructed with a durable aluminum heatsink, the Rockford Fosgate 250.2 maintains optimal temperature during operation, ensuring long-lasting performance and minimizing thermal issues. The amplifier also features RCA inputs, making it compatible with a wide range of audio sources, enhancing its versatility for various setups.

In summary, the Rockford Fosgate 250.2 is a reliable and robust car amplifier that combines high power output with advanced technologies and user-friendly features. Its efficient design, customizable settings, and quality construction make it an excellent choice for anyone looking to improve their vehicle's sound system. Whether for day-to-day driving or road trips, the Rockford Fosgate 250.2 provides an audio experience that is both powerful and enjoyable, reinforcing Rockford Fosgate's reputation as a leader in the car audio industry.
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