Stimmen - 4, Durchschnittliche Bewertung: 4 ( )

Hersteller: Ashly Dateigröße: 144.37 kb Dateiname: Unterrichtssprache:

The inputs are configured for pin 2 hot, meaning that a positive voltage applied to pin 2 will result in a positive output voltage across the speaker terminals. Pin 2 of the XLR jack is equivalent to the tip of the 1/4" TRS jack. An optional input transformer is available on all MFA amplifiers. Balanced Inputs It is recommended that balanced input connections be used whenever possible to reduce ground-loop and environment-induced hum and noise. The (+) signal is on pin 2 of the XLR, and the tip of the phone jack. The (-) signal is on pin 3 of the XLR, and the ring of the phone jack. Unbalanced Inputs If an unbalanced input connection is used, then the (-) connection (XLR pin 3) should be connected to input ground ( XLR pin 1). If the 1/4" input jack is used unbalanced, the use of a mono (tip-sleeve) plug will automatically tie the (-) connection to input ground. Never float pin 2 or pin 3 when using an unbalanced signal. Figure 7.1: Balanced Input Connections Figure 7.1a: Unbalanced Input Connections Operating Manual - MFA-8000 and MFA-6000 Power Amplifier Input Ground The CHASSIS GROUND terminal is internally connected to the chassis, the AC earth ground, and the power amplifier’s signal ground. The INPUT GROUND terminal is tied to the XLR pin 1 and the 1/4" jack sleeve. It is recommended that the input and chassis ground terminals remain connected with the factory-supplied jumper strap. In situations where the power amp and its signal source are separated by great distances, a ground voltage difference may exist between the amp’s chassis ground and the input cable’s ground. Connection of these two grounds through the jumper strap may cause large ground currents to flow (which is known as a ground loop), causing a hum noise in the amp’s output. Unless you have such a situation with a hum problem that cannot be solved by using balanced input connections, the ground jumper strap should remain in place. 7.2 Normal/Bridging Switch This switch selects between NORMAL mode in the “out” position where both channels are in-phase, and BRIDGING mode in the “in” position where channel 1 input is used to drive both channels, inverting the phase of channel 2. In BRIDGING mode, the channel 1 red binding post is the (+) in- phase speaker output terminal and the channel 2 red binding post becomes the (-) out-of-phase speaker terminal. It is not necessary to depress the MONO switch in order to operate in BRIDGED mode. The BRIDGING switch overrides either setting of the Stereo/ Mono Switch. 7.3 Stereo/Parallel Mono Switch This switch selects between STEREO mode in the “out” position and PARALLEL MONO mode in the “in” position. In PARALLEL MONO mode, channel 1 and channel 2 inputs are internally tied together before the input attenuator, allowing discrete channel control of a mono signal. CAUTION: Be sure not to have two signal sources connected to ch.1 and ch.2 inputs when in parallel mono mode, as it would short-circuit these two signals and result in no output. 7.4 Level Controls The level controls allow attenuation (calibrated in dB) of the input signal. In PARALLEL MONO mode, channel 1 and channel 2 inputs are tied together, while still preserving independent level control per channel. In BRIDGED mode, use only channel 1 level control. It is recommended that the level controls be operated at full level (0 dB attenuation) in most situations to maximize the headroom in the signal source. 7.5 Speaker Outputs - Binding Posts Caution: This product can deliver enough energy to the output terminals to produce a lethal shock. Do not attempt to wire the amplifier when the power is turned on. ono Mode dged n 2+ is ne n 1+ is po 1+ is POS 1-is GND 1+ is POS 1-is GND al Channel nnector an.1 n 1+, Pin1 an.2 n 2+, Pin2 1 Channel 2 Figure 7.5: Output Section A pair of dual banana binding posts provide the stereo speaker outputs. In BRIDGING mode, the channel 1 red binding post is the (+) in-phase speaker output terminal and the channel 2 red binding post becomes the (-) out-of-phase speaker terminal. CAUTION! NEVER CONNECT THE TWO RED BINDING POSTS TOGETHER OR CONNECT EITHER RED BINDING POST TO A BLACK BINDING POST! Operating Manual - MFA-8000 and MFA-6000 Power Amplifier 7.6 Speaker Outputs - Speakon Connectors Neutrik Speakon connectors are provided to connect with the Neutrik NL4FC 4-conductor plug. For the channel 1 and 2 Speakon connectors, the following pin assignment is used: Pin 1+ = speaker hot Pin 1- = speaker ground The third Speakon connector in the center provides a stereo connection if operating in stereo mode or a bridged connection if operating in bridged mode. The pin assignment for this connector is: Stereo Mode Bridged Mode Pin 1+ = Ch.1 hot Speaker hot Pin 1- = Ch.1 ground Pin 2+ = Ch.2 hot Speaker return Pin 2- = Ch.2 ground 8. INPUT OPTIONS Input option panels are available to provide built- in features such as a stereo compressor-limiter, a mic and line mixer, a crossover for bi-amplified systems, and input trans...

Herunterladen

Geben Sie zwei Ziffern: