Rockford Fosgate 500.2 manual Dynamic Power Measurements

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DYNAMIC POWER MEASUREMENTS

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 standards. 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 manufacturers, 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 milliseconds. The signal is gradually increased in level until the amplifier's output exceeds 1% Total Harmonic Distortion (THD). At 1% distortion becomes audible, therefore, any power produced above that level is considered unusable. 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.

A 4 ohm speaker may experience a drop in impedance 4-6 times lower 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 (compliance 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 of these impedances is also tested at –60°, –30°, 0°, +30° and +60° phase angles. These different impedances and phase angles represent the shifts in impedance and phase that can occur in a typical loudspeaker.

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.

 

 

 

 

 

Audio Graph – The PowerCube™

 

Output Power, in watts, is listed on the left hand side

 

 

 

MODEL BEING

VOLTAGE FROM

 

x2 = STEREO

 

for each impedance at each phase angle.

 

 

 

 

 

 

 

 

TESTED

 

 

 

 

 

 

 

BATTERY

MONO = BRIDGED MONO

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Amplifier: PUNCH 200.2 14.4V x 2

 

Rated Power : 100 W @ 4 Ohms

What is an Amplifier?

 

 

Serial No:

 

 

 

 

 

 

 

 

Owner

: ROCKFORD CORPORATION

 

 

 

An amplifier by definition is a voltage generating

 

 

8Ω*–60°

85

W

 

 

 

 

 

device, recreating the signal which is input to it

 

 

 

 

 

 

 

 

 

–30°

84

W

 

POWER

 

 

50V

 

 

0°

84

W

 

 

 

identically but with increased volume. It will be

 

 

 

IN

 

 

 

 

 

30°

84

W

{WATTS

 

 

 

connected to a reactive load (the speaker). The

E

60°

86

W

 

 

 

 

 

C

4Ω*–60°

162

W

 

 

 

 

30V

impedance of this load and phase of the signal

N

–30°

157

W

 

 

 

 

 

A

 

 

 

 

 

0°

156

W

 

 

 

 

 

P E D

 

 

 

 

 

passing through the load will vary, dependent upon

30°

157

W

 

 

 

 

 

60°

162

W

 

 

 

 

10V

the frequency of the input signal (music).

M

2Ω*–60°273 W

 

 

 

 

 

 

 

 

 

 

 

 

I

–30°

258

W

 

 

 

 

 

 

 

 

 

 

 

8Ω

 

 

 

0°

251

W

 

 

 

 

 

 

 

 

 

 

 

4Ω

Therefore, a perfect amplifier will be able to main-

 

 

30°

256

W

 

 

 

 

 

 

60°

271

W

 

–60°(Cap)

0°

 

2Ω

 

 

1Ω*–60°

390

W

 

 

1Ω

{

tain the same output voltage regardless of load

 

 

 

 

 

 

 

–30°

356

W

 

 

 

(Ind) +60°

 

 

0°

346

W

 

PHASE{ANGLES

Impedance

characteristics and will not alter the signal it is

 

 

 

 

 

30°

352

W

 

 

 

 

 

reproducing. A perfect amplifier when measured by

 

 

60°

390

W

 

 

 

 

 

 

• Example of a Punch 200.2 PowerCube

 

the Audio Graph 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.

O U T P U T V O L T A G E

As you can see by the PowerCube and as you will experience by listening, your Punch amplifier is a GREAT AMPLIFIER!

– 27 –

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Contents Punch Practice Safe Sound Table of Contents T T I N G S TA R T E DAccessory Pack IntroductionTechnical Design Features Transnova TRANSconductance NOdal Voltage AmplifierStereo Pass-Thru Bass EQ Design Features Amplifie Installation Considerations Tools NeededBattery and Charging Mounting Location SWI R I N G TH E SY S T E M Using Passive Crossovers Table of Crossover Component Values 6dB/Octave High-Pass 6dB/Octave Low-Pass3386 Using the XcardCustomizing the Xcard 7234Xcard Resistor Chart Xcard Configurations Configuring a 12dB/octave FilterBypassing the Crossover Configuring a 24dB/octave Filter Configuring a 12dB/octave Bandpass FilterInstallation Power ConnectionsStereo Operation EZ-Bridged Operation Using the Balanced Line Input Connecting the BLTDisconnect Speakers from the amplifier AC Voltmeter set to AC VoltsRockford Fosgate Accessories Balanced Line Transmitter FG-BLTEnergy Storage Capacitors XCard CrossoversAmplifier does not turn on TroubleshootingSymptom Diagnosis Remedy Amplifier has no soundSpeaker Output Low Or DistortedAmplifier Noise Quick Check for Troubleshooting CAR Audio Systems Autosound 2000sTime for Processors Dynamic Power Measurements Specifications WattsLimited Warranty Information O R M Introducción Ubicación DE LOS AmplificadoresOperación mono/estéreo Montage Montage dans le coffreOpération stéréo/mono Tri-mode Einleitung EinbauortLinken Phasen Schalter auf 0 stellen Stereo/Mono BetriebTerminale B+ cavo positivo IntroduzioneDove Posizionarlo Terminale GND cavo negativoStereo/Mono Operation Fase sinistra dellinterruttore posizionata suMade in the USA

500.2 specifications

The Rockford Fosgate 500.2 is a powerful, high-performance amplifier that embodies the brand's signature commitment to quality and innovation in the world of car audio. Designed for audiophiles and casual listeners alike, this amplifier can dramatically enhance the sound experience in your vehicle, making it a popular choice for many car enthusiasts.

At the heart of the Rockford Fosgate 500.2 is its robust power output. The amplifier delivers a remarkable 250 watts per channel at 2 ohms, which ensures that even the most demanding speakers receive ample power. This efficiency allows users to enjoy loud and clear sound without distortion, even at higher volumes. The amplifier's dynamic power management ensures that the audio performance remains consistent across various listening scenarios.

One of the standout features of the 500.2 is its Smart Technology, which includes built-in thermal protection and short circuit protection. This design not only prolongs the life of the amplifier but also enhances performance by preventing overheating and damage during extended use. This is especially beneficial for users who love listening to music at high volume for prolonged periods.

The 500.2 also features a variable high-pass and low-pass crossover, allowing for precise sound tuning. Whether you are aiming for deep bass or crisp highs, the adjustable crossover settings enable users to customize their audio experience to their liking. With a frequency response range of 20 Hz to 20 kHz, this amplifier is versatile enough to handle a wide array of musical genres and audio formats.

Additionally, the amplifier's compact design allows for easy installation in various vehicle types without sacrificing valuable space. Its sleek and stylish chassis not only provides durability but also adds an aesthetic touch to your audio setup.

Lastly, the Rockford Fosgate 500.2 is built with quality materials that make it reliable and long-lasting. The unit's professional-grade construction ensures that it can withstand the rigors of daily use in a car environment. Overall, the Rockford Fosgate 500.2 is an excellent investment for anyone looking to upgrade their car audio system, offering powerful sound, innovative technology, and customization features that cater to both casual listeners and serious audiophiles.