TECHNICAL DESIGN FEATURES

Many of the solutions to common design problems encountered by Rockford Fosgate engineers created entire new circuit designs as well as new ways to construct the Punch 250.2 and 250.1 Power Amplifiers. In our flagship amplifiers, no expense 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. A low voltage drive stage is the same principle used in high quality preamplifiers to produce high linearity and wide bandwidth.

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trans•nova circuitry

The resulting design utilizes an output stage with a simpler gain structure and a shorter total signal path than conventional high voltage (bi-polar) designs. The number of stages is reduced from five or more to three. The output stage is further refined into a trans-impedance stage (current to voltage converter) to achieve a short loop (fast) negative feedback. The output stage 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 (Dynamically Invariant AMplification Optimized Nodal Drive - patent pending) is an important advance in circuit 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 high frequency distortion by allowing the driver to operate with 20dB or more of current headroom, whereas traditional drivers 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 power supply ground of the amplifier. This is accomplished by allowing the source unit to control the potential “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.

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Rockford Fosgate 250.2 manual Technical Design Features, Transnova TRANSconductance NOdal Voltage Amplifier
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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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