Instruction/ maintenance manual of the product MPC JBL
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21 MPC Series Power Amplifiers Owner ’ s Manual TD-000074-00 TD-000074-00 R e v . C.
1 T able of Contents T able of Contents .............................................................................................................. ..................................................................... 1 W ar ning notices ..........
2 Rack Mounting Precautions T o a void dama ge to the amplifier mounting ears and/or rack rails , the amplifier must be supported at all four corners when used in portable racks . Consult JBL Ser vice Dept for av ailability of R ear Support Brac ke ts .
3 Description T he MPC Series from JBL is a line of professional pow er amplifiers specifically designed for contracting applica tions . There are six models , eac h with two independent channels .
4 1 22 5 12 12 33 4 4 5 12 2 4 12 12 CH1 CH2 CH1 CH2 BRIDGE MONO BRIDGE MONO LOW IMPEDANCE LOW IMPEDANCE DIR. OUTPUT DIR. OUTPUT ISOL.OUTPUT ISOL.OUTPUT AUDIO TRANSFORMER AUDIO TRANSFORMER 70V 70V 25V.
5 b) Dept hThe amplifiers require a r ac k depth of 45.7 cm (18 in) to clear the rear support ears . T he r ear panel is 42.9 cm (16.9 in) behind the plane of the fr ont mounting rails , allo wing some room for r outing of wires .
6 Outputs Cover ed barrier strips located on the r ear panel allow safe , shockproof speaker ca b le connec- tions to the amplifier outputs . See the dia grams for details on connecting speaker s and/or distributed (25V , 70V , 100, 140V , and 200V) lines .
7 Driving Distributed Lines Make sure the sum of the pow er settings of all the speaker s does not exceed the po wer rating of the amplifier . Be aware tha t the actual power dra w on some loudspeakers can v ary considerably from their tap labels .
8 Loading an amp channel Be careful not to o v er load the c hannel when combining low- impedance and distributed loads on the same amplifier c hannel, because either load af fects the amount of p ow er a vaila ble for the other . T he next two par ag raphs explain how the y load the amplifier output.
9 The tables below ar e general guidelines on which combinations ar e acce ptable. MPC200T Sum of Speaker T aps Connected to AUDIO TRANSFORMER Outputs 0 W 22 W* 44 W** 88 W*** 175 W**** Load connected.
10 Using Multiple Distributed Line V oltages The MPC amplifiers allo w you to connect distributed lines to an y of the 100V , 70V , and 25V outputs at the same time. F or example, a single c hannel could driv e both a 70V and a 25V line; such flexibility could sa ve y ou the e xpense of an additional amplifier .
11 Bridged Mono Input Connection The follo wing dia grams show input and output connections for bridged mono mode . Note that the MPC200 and 200T models use a different method for bridged mono than do the MPC300, 300T , 600 & 600T .
12 Low Impedance Bridged Mono Applications T he bridged mono mode produces higher output v oltages with the trade-off of requiring a higher impedance load and providing a slightly lo wer damping factor . Never - theless , it is an eff ectiv e way of pr oviding v er y high power le vels to loudspeak er s such as 4 Ω or 8 Ω subw oofers.
13 Controls T he c hannel atten uator controls , labeled in dB of atten uation, are located on the r ear panel. T hey ha ve 11 detents and are adjustable from 0 dB (full gain) to ∞ (full attenuation). Displays T he LED displa ys on models MPC200 and 200T are dif f erent from those on models MPC300, 300T , 600, and 600T .
14 AC Power The MPC amplifiers are av ailable for 120 or 220240 V A C, 50 or 60 Hz operation. Eac h amplifier is factory configured for the line volta g e of the market into whic h it is sold. Operation Before fir st turning on the amplifier, tur n the gain controls of fi.
15 Shor t-Circuit Pr otection MPC amplifier s use the prov en Output A veraging short circuit protection system. The circuit per mits full output cur rent even into r esistiv e or r eactiv e 2 Ω load, but reduces the current saf ely by about 75% if the output is shor ted.
16 Specifications Direct Output Models Audio Transfo rmer AND Direct Outputs Electronics MPC200 MPC300 MPC600 MPC200T MPC300T MPC600T Direct P ow er Out 4 Ω bridge 1 kHz, 1% THD 1 700 W 900 W 1800 W.
17 Power Consumption Some background on A C ratings is necessar y to fully understand po wer consumption specifications . Essentiall y , ther e are thr ee ratings of interest: (1) the legal operating .
18 Heat Emission Any pow er that enters the amplifier thr ough the power cor d and does not exit through the speaker outputs turns into heat, which the amplifier m ust rid itself of by exhausting it to the outside . In indoor use this may pr esent a challenge to the building s air conditioning system.
19 T roubleshooting PROBLEM: Channel will not come out of muting . Reduce the gain to ∞ a tten uation. If this releases the muting , raise the gain bac k up slowly while you watc h the SIGN AL and CLIP indicators .
20 For Further Assistance WITHIN THE UNITED ST ATES: General Infor mation or T echnical Assistance F or more inf or mation on JBL products , inc luding these power amplifier s , contact your nearest JBL Professional products dealer or the JBL factory at the address below .
22 JBL Professional 8500 Balboa Boulevard, P .O. Box 2200 Northridge, California 91329 U.S.A. A Harman International Company MPC MANUAL 6/98.
An important point after buying a device JBL MPC (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought JBL MPC yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data JBL MPC - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, JBL MPC you will learn all the available features of the product, as well as information on its operation. The information that you get JBL MPC will certainly help you make a decision on the purchase.
If you already are a holder of JBL MPC, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime JBL MPC.
However, one of the most important roles played by the user manual is to help in solving problems with JBL MPC. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device JBL MPC along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center
