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OWNER’S MANUAL
DPA 4245 / DPA 4260 POWER AMPLIFIER
Features
• 2 x 450 watts output power capacity DPA 4245
• 2 x 600 watts output power capacity DPA 4260
• floating 100 V / 70 V / 25 V power outputs (isolated outputs)
• low impedance outputs (direct outputs)
• bridged mode operation, switchable
• all outputs are protected against idling and short-circuit
• mains supply 230 V AC 50/60 Hz
• POWER REMOTE function
• service mains switch
• active ventilation via 2 temperature-controlled DC-fans
• el
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CONTENTS Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Installation Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Rear View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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DESCRIPTION Especially designed for permanent installations, the DPA-Series power amplifiers offer performance-con- sistent and reliable operation of PA-systems with 2 individual loudspeaker lines, each. Therefore, DPA-Series power amplifiers are most suitable for company intercom, alarm and background music transmission installations in offices and commercial areas, congregation and sport centers, schools, houses of worship, hotels, hospitals, shopping malls and super markets, cruise ships, and
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Installation Notes Generally, it is important to install the power amplifier in a way, that ensures unhindered front-to-rear air circulation. When installing the power amplifier in a closed rack-shelf system, please make sure that adequate air-flow is guaranteed. The space between the rear panel of the amplifier and the inner wall of the rack-case has to be at least 60 mm x 330 mm. A free space of at least 100 mm above the rack-shelf system is needed to provide sufficient air circulation. Since,
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Inputs INPUT CHANNEL A&B With an input sensitivity of 775 mV = 0 dBu and an input impedance of 20 k ohms, the electronically balanced inputs – INPUT CHANNEL A&B – are meant for the connection of control amplifiers, audio controllers, mixing consoles, etc. Peripheral pieces of audio equipment are either connected via the XLR- type input connectors or using the parallel-linked binding posts. For the latter option you can utilize the supplied screw-plugs. Thus, carrying the audio signals through to
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figure: block diagram input channel A figure: printed board assembly area channel A – transformer retrofitting Level Control dB-scaled rotary controls for adjusting the power amplifier’s overall ampli- fication. This control should be positioned between the 0 dB and the -6 dB marks to prevent distortion in source devices. The labeling indicates the actual attenuation applied to the internal specified factor of amplification. Input Routing If the switch is set to parallel/mono, the input connecto
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Power Outputs – AUDIO TRANSFORMER OUTPUTS The two integrated output transformers convert the power amplifier’s nominal output voltage to the commonly used loudspeaker line voltage standards – 25 V, 70 V, and 100 V. These voltages are simultaneously present at the correspondent floating outputs of the binding post strip. The two power amplifier channels can be operated using any possible output voltage combination. Simultaneous operation of low impedance loudspeaker systems and floating loudspeak
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Power Outputs - Isolated Outputs 25 V The floating 25 V output is mainly used for driving low impedance loudspeaker systems (4 - 16 ohms). Because of the effect of line attenuation, the distance between power amplifier and loudspeaker systems should not exceed 50 meters. It is further important that the total impedance of the entire loudspeaker network does not decline the nominal load impedance of the 25 V output. For details on the nominal load impedance of the 25 V output, please also refer t
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Bridged Mode Doubling the power amplifier’s output power is accomplished by engaging bridged mode operation, where the two power amplifier output stages are linked for push-pull operation. In other words, a monaural power amplifier is “created” offering double the output voltage and double the output power capacity of a single channel. As a result you are provided with floating 50 V, 140 V, and 200 V as well as with a direct output with doubled nominal output voltage. If the BRIDGED-MODE switch
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GROUND Lift Switch The ground lift switch helps is a perfect means for eliminating possible ground noise loops. In case the power amplifier is operated together with other equipment inside of a rack shelf system, the switch should be set to its GROUNDED position. When using the power amplifier together with other equipment that operates on different ground potentials, the switch should be set to UNGROUNDED. Power On And Remote Control When the power amplifier is operated via power remote start (
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Protection Circuitry The DPA-Series power amplifiers are equipped with extensive protection circuitry: • initial current inrush limiter • power-on delay • RF and DC protection • Back-EMF protection • limiters for the audio signals • output peak-current-limiters • thermal overload of the heat sink • thermal overload of the mains transformer • output voltage overload limiters High-level signals in the low frequency range can drive the output transformers of power amplifiers that do not provide aud
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Mains Operation And Leakage Power The mains power consumption as well as the leakage power is stated for driving the power amplifier at different levels. All the values were measured at nominal load via the 100 V output with two channels driven. The shown values differ only slightly when the appliance is operated at different nominal output voltages or in the Direct Out mode. mains operation at the U [V] mains I [A] P P [W] P [W] P [W] BTU/hr mains mains [VA] mains out v 100 V output DPA 4245 i
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Technical Specifications: DPA 4245, DPA 4260 Amplifier at rated conditions, both channels driven, direct outputs with 8Ω loads, isolated outputs with rated load and voltage, unless otherwise specified. DPA4245 DPA4260 DUAL MODE Direct Output Isolated Outputs Direct Output Isolated Outputs Output Definition 8Ω 4Ω 100V 70V 25V 8Ω 4Ω 100V 70V 25V Load impedance or rated output voltage Rated Load Impedance 28.5Ω 14Ω 1.8Ω 20Ω 9.8Ω 1.25Ω isolated outputs only Maximum Midband Output Power 240W 450
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BRIDGED MODE Direct Output Isolated Outputs Direct Output Isolated Outputs Output Definition 8Ω 200V 140V 50V 8Ω 200V 140V 50V Load impedance or rated output voltage Rated Load Impedance —— 57Ω 28Ω 3.6 Ω ——- 40Ω 19.6Ω 2.5 Ω isolated outputs only Rated Output Power 560 W 700 W 700 W 700W 600W 1000W 1000W 1000W THD<0.2%, 45Hz ... 20kHz Maximum Bridged Output Power 900W 820W 800W 780W 1200W 1180W 1160W 1140W THD=1%, 1kHz GENERELLPower Requirements 230V / 50Hz...60Hz Power Consumption at 1/8 maximu
