Connecting the GFA-555se, Up to 24 feet, Up to 36 feet

CONNECTING THE GFA-555se

When connecting the ampliﬁer to the loudspeaker, it is vital to maintain proper polarity (positive to positive, negative to negative). On the GFA-555se , the positive terminal is color coded RED and labeled “+”, and the negative is color coded BLACK and labeled “-”. The positive terminal on the speaker will be color coded RED, or will be labeled “+”, “pos”, “positive”, “8 ohms” or “4 ohms”. The negative terminal on the speaker will be color coded BLACK, or will be labeled “-”, “neg”, “negative”, “C”, “Common”, “G”, or “ground”.

It is recommended that your speaker cables be terminated with “U” type spade connectors. These will give the most contact area insuring long-term reliability. The spade connector should have a maximum width of 0.57 inches and an opening width of no less than 0.25”.

To properly connect the speaker cable to the binding posts, turn the insulated head of the binding post clockwise until the wire or connector is ﬁrmly secured. Finger pressure is sufﬁcient and you should not use pliers or other tools which could damage or over-tighten the binding-post assembly. The binding posts have been designed in such a way that ﬁnger pressure is all that is required to cause a “pinching” action among the different metal surfaces to ensure proper connection.

It is very important to use the correct size of wire in order to avoid unnecessary loss of ampliﬁer power in the cable, reduction of ampliﬁer damping factor and other undesirable conditions. Sound audio engineering practice suggests the use of at least AWG16, stranded, copper cable. Recommended capacitance of the speaker wire should not exceed 5OpF per foot. This insures high frequencies will not be rolled-off.

All loudspeakers having a nominal impedance down to 4 ohms can be connected to and driven by the GFA-555se. The ampliﬁer can drive these low-impedance speakers at more than adequate power levels with no difﬁculty. It should be noted that many loudspeaker systems which are nominally rated at 4 ohms drop in impedance, in some parts of their frequency range, to as low as 2 ohms (and sometimes less). You will not experience difﬁculties even with these very low impedance loads unless you demand excessively high volumes levels from your system.

It is suggested to follow this chart for speaker lengths and wire gauges. If longer runs are needed, it is best to consult with your ADCOM Dealer to maximize the performance of your system with your exact conditions.

up to 24 feet

AWGI6

up to 36 feet

AWGI4

up to 58 feet

AWGI2

STEREO/BRIDGED MONO INPUT/OUTPUT

The GFA-555se can be used as a very powerful mono ampliﬁer to drive 8-ohm impedance loudspeakers when in its “bridged” mode. No modiﬁcation to the ampliﬁer is necessary for operation in the bridged mode, nor are any additional accessories required. However, you will need two GFA-555ses for stereophonic reproduction, if you are using them in the bridged mono mode.

GFA-555se specifications

The Adcom GFA-555se is a high-performance audio power amplifier that stands out for its robust design and exceptional sound quality. Renowned among audiophiles, it offers a blend of remarkable power output and fidelity, making it suitable for a wide range of audio systems.

One of the main features of the GFA-555se is its impressive power output, rated at 200 watts per channel into 8 ohms and 330 watts per channel into 4 ohms. This ample power allows it to drive a variety of speakers efficiently, delivering dynamic and impactful sound reproduction. The amplifier is designed to handle both high and low frequencies with precision, ensuring a balanced audio experience.

In terms of technology, the GFA-555se employs a classic Class AB design, which is known for its ability to combine the efficiency of Class B operation with the linearity of Class A. This results in lower distortion and better thermal management, contributing to a cleaner sound, particularly at high volumes. The amplifier also incorporates a high-speed output stage, which enhances transient response and enables the reproduction of fast-paced musical passages without degradation.

Another notable characteristic of the GFA-555se is its build quality. The chassis is constructed from heavy-duty aluminum, which not only results in durability but also helps to dissipate heat effectively. This is crucial in maintaining performance and longevity, as overheating can lead to shortened component life. Additionally, the amplifier features a massive power supply with a large transformer, providing stable voltage and current to the output stage, which further enhances audio performance.

The GFA-555se is equipped with unbalanced RCA inputs and can be easily integrated into existing audio setups, making it a versatile choice for both home theater and stereo systems. With its impressive parasitic rejection and low noise floor, it ensures that the audio signal remains clean and unaffected by external interference.

In conclusion, the Adcom GFA-555se is a powerful and reliable amplifier that combines advanced technologies with robust construction. Its ability to deliver high-quality sound across a broad range of frequencies, along with its impressive power output and efficient design, makes it a popular choice among music enthusiasts and professionals alike. Whether used as part of a high-end audio system or in a home theater setup, the GFA-555se continues to be a respected component for achieving an immersive listening experience.