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.

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Rockford Fosgate 400, 360, 1000 About the Dynamic Power Measurements, Music, Listening to Loudspeakers Not Resistors
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1000, 360, 400 specifications

Rockford Fosgate is a renowned name in the audio industry, especially recognized for their high-performance car audio systems. Among their range of products, the Rockford Fosgate Punch series, including models like the R1000-1D, R360-4, and R400-4, stands out due to their outstanding features and cutting-edge technology.

The R1000-1D is a monoblock amplifier that delivers a staggering 1000 watts of RMS power at 1 ohm. This powerhouse is particularly suited for subwoofers, maximizing bass output with minimal distortion. Its Class D topology enhances efficiency, ensuring that users get more power with less heat generation, which is a common challenge in high-performance audio systems. Integrated into the design are adjustable low-pass filters and bass boost controls, allowing users to tailor the sound to their liking. Additionally, it features an LED indicator that provides real-time feedback on the amplifier's status, making monitoring easy for users.

Next up, the R360-4 is a versatile four-channel amplifier that can deliver 360 watts of RMS power. This model is ideal for powering multiple speakers or a combination of speakers and subwoofers. With its high and low-level inputs, it is compatible with a variety of audio sources, making it a flexible choice for car audio enthusiasts. Notably, the built-in crossover system provides precise sound processing, ensuring that every component of the audio spectrum is handled efficiently. This amplifier also utilizes Rockford Fosgate's proprietary technology to reduce noise and interference, creating a cleaner sound experience.

Lastly, the R400-4 brings another level of performance to the table with its 400 watts of RMS power output, designed for full-range applications. This amplifier features a compact design, allowing for easy installation in tight spaces. Like the R360-4, it also features high and low-level inputs along with built-in variable crossovers. The thermal and speaker short protection circuitry ensures safety and longevity, providing peace of mind for users.

All three models exemplify Rockford Fosgate's commitment to excellence, making them a popular choice among car audio enthusiasts who prioritize power, versatility, and sound clarity. Whether you are seeking a powerful bass experience or a balanced audio system, the R1000-1D, R360-4, and R400-4 are designed to elevate any car audio setup to new heights.
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