Reference 7250/7260 series II Five/Six Channel Amplifier OWNER’S MANUAL B & K Components Ltd. P/N 13007 Rev.
B&K Components, Ltd 2100 Old Union Road Buffalo, New York 14227 P/N 13007 Rev.
Table of contents Safety Precautions page 2 Purpose and function page 3 Design and construction page 3 Features page 3 Rear panel view page 4 Rear panel description page 4 - 6 Level controls page 5 Inputs page 5 - 6 Outputs page 6 Control Muting page 8 - 9 System installation page 7 Making the connection page 7 - 8 Troubleshooting page 10 Care and cleaning page 10 Specifications page 11 Warranty page 12 Accessories included: Manual and Power cord Page 1 P/N 13007 Rev.
SAFETY PRECAUTIONS PLEASE READ BEFORE INSTALLING WARNING: TO PREVENT FIRE OR SHOCK HAZARD, DO NOT EXPOSE THIS UNIT TO RAIN OR MOISTURE. The lightning flash with arrowhead, within an equilateral triangle, is intended to alert the user of the presence of uninsulated “dangerous voltage” within the product’s enclosure that may be sufficient magnitude to constitute a risk of electric shock to you.
The Reference 7250/7260 series II purpose and function The Reference 7250/7260 series II is a high current, five/six channel power amplifier. It is designed to be used in all types of audio or audio/video systems. Design and construction The Reference 7250/7260 series II utilizes high quality electronic circuitry to achieve an environment wherein a detailed, transparent, and highly musical sound can be realized.
Rear Panel View 1. AC fuse holder 2. AC Input receptacle 3. Speaker outputs 4. Amplifier control muting input/output 5. Level controls 6. Inputs 7. Speaker fuses Rear panel description 1. AC fuse holder - Holds the AC Line fuse. This fuse is a 15 Amp / 250 Volt Slow Blow fuse. Replace with same type and value fuse only. 2. AC Input receptacle - For attaching the supplied AC power cord to the amplifier. 3. Speaker outputs - For connecting the speakers to the amplifier. Explained further on page 6. 4.
. Speaker Fuses - Protection against amplifier damage in the case of shorted speaker wires. Replace fuse with same value 6 AMP SLOW BLOW only! IMPORTANT! Level controls When using the level controls, first start with them turned all the way up (clockwise). Then adjust them according to your system requirements to match the sound level coming from each speaker. This is a rough adjustment for matching different driver impedances.
Here is a typical preamplifier to amplifier setup: Outputs Five way binding posts are provided. One pair for each channel. They are designed to accept a banana-type plug or spade lug connector (shown below) and are color coded for easy identification. The positive (+) post should always be connected to the speakers (+) jack. The negative (-) post should always be connected to the speakers (-) jack. Spade connector Banana jack Here is a typical amplifier output setup: Page 6 P/N 13007 Rev.
System Installation There will most likely be a number of cables involved in the installation of your home entertainment system. Preplanning is essential in order to maximize system efficiency. We recommend the following as a means of helping you reach that goal: § Make a diagram of your proposed system by laying out the relative location of each component in the system. Then lay out the proposed cable runs between them. Number each cable and record its length on the diagram for future reference.
§ Connect the wires from your speakers to the appropriate outputs on the amplifier. It is absolutely essential that you observe correct polarity in these connections. Example: If you connect your left front output of your preamplifier to channel 4 input on the amplifier, remember to connect your left front speaker wires to channel 4's outputs. Always observe polarity when connecting speakers, connect amplifiers (+) to the speakers (+) and amplifiers (-) to speakers (-). § Double check all connections.
If a source other than a B&K series preamplifier is used to control multiple amplifiers, only the control output voltage from the source is critical. It must be within the range, as indicated on the rear panel, 5-24 volts DC is required. The amplifier will provide each successive amplifier with a control voltage of 12 volts DC for reliable operation. The amplifiers control output may be used as a source of 12 VDC @ 125 mA for other user applications as well. DO NOT POWER MOTORS WITH THIS CIRCUIT.
Troubleshooting PROBLEM POSSIBLE CAUSE No sound 1. (‘on’ LED not illuminated) 2. 3. 4. No sound on some or all selected channels (‘on’ LED illuminated 1. 2. 3. 4. 5. 6. Sound lacks direction, bass weak 1. Power cord not plugged in Power off at AC source AC power inlet fuse blown or faulty Control switch in the wrong position Speaker leads loose or faulty. Line stage to amp cables loose or faulty. Source to line stage cables loose or faulty. Line stage or source not correctly selected.
Reference 7250/7260 series II SPECIFICATIONS Power rating: 8 ohms 4 ohms 200 watts @ 1 kHz 375 watts @ 1 kHz Frequency response 5 Hz - 45 kHz Input sensitivity 1.4 Volts THD (S+N) 0.09 % @ 1 kHz Input impedance 33.2 k ohms Damping factor 450 Current (peak to peak) 75 Amps Slew rate 14 V / usec Dynamic headroom 1.2 dB S/N (A-weighted) 95 dB Voltage gain 28 Line voltage 120/220/240 VAC switchable Dimensions (O.A.) 17"(w) X 19.25"(d) X 7.
Limited Warranty B&K Components Ltd., referred to herein as B&K, warrants your B&K equipment against all defects in material and workmanship for a period of five years from the date of purchase. This warranty applies only to the original purchaser and only to equipment in normal residential use and service.
B&K Components, Ltd 2100 Old Union Road Buffalo, New York 14227 P/N 13007 Rev.
B&K Components, Ltd. 2100 Old Union Road Buffalo, New York 14227 www.bkcomp.com P/N 13007 Rev.
