User manual B&K ST55.2

[. . . ] ST55. 2 OWNER'S MANUAL B&K P/N13436 0702 B&K Components, Ltd. , 2100 Old Union Road, Buffalo New York 14227-2725 Phone 1-800-543-5252 or (716) 656-0026, Fax (716) 656-1291 E-mail: info@bkcomp. com Web: www. bkcomp. com ii TABLE OF CONTENTS Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Purpose and Function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Design and Construction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] The black (-) post should always be connected to the speakers (-) jack. Spade connector Banana jack 5 Here is a typical amplifier setup: MINUS PLUS PLUS MINUS RIGHT LEFT (-) (+) )+( )-( Channel 1 Channel 2 INTERNAL BUS STRUCTURE In order to gain access to the internal bus structure, you must first remove the top cover. The jumper modules may be seen on the circuit board just behind the level controls. By arranging the jumpers allows you to configure the amplifier for different applications. If you wish to use the amplifier as a stereo (two channel) amplifier, you need not change any of the settings. In order to reconfigure the ST55. 2's channels, remove the source control group jumper from its present position (if necessary) and install it on the terminal you wish to select as the source for that channel. Make sure it has been inserted on both terminal pins of the jumper modules. To complete the configuration, the volume group jumper should be placed at either the `USE VOL' or `NO VOL' terminal depending on you configuration. Note: A channel that is not being used in your configuration should have its jumper plugs installed at the default position as shown above. 6 JUMPER DESCRIPTION The jumper modules are used in configuring each channel. Each jumper terminal location is conveniently labeled as to the source it can be configured to provide. R BUS - Along with being the right channel input, it is used as the input to the right bus and the right source for the `L+R BUS'. Because it is a BUS input, any signal input here would appear at the `R BUS' jumper terminal for both of the ST55. 2's jumper modules. NOT USED R BUS L+R BUS L BUS NO VOL USE VOL L+R BUS - Installing a jumper plug at this terminal on either of the two internal jumper modules selects the combined signal being carried by both the left and right inputs. If the left bus and right bus are being used to carry stereo right and left channels, a jumper plug installed at the `L+R BUS' location will provide a true L+R mono output. L BUS - Along with being the left channel input, it is used as the input to the left bus and the left source for the `L+R BUS'. Because it is a BUS input, any signal input here will appear at the `L BUS' jumper terminal for both of the ST55. 2's jumper modules. NO VOL - If volume control is desired only from the source, or if outputs are being combined to obtain higher power, the jumper plug should be installed at the `NO VOL' location. USE VOL - If volume control is desired at the amplifier, beyond that provided at the source, a shorting plug is installed at the `USE VOL' location. The `USE VOL' setting SHOULD NOT be used when channels are bridged or combined. Invert Jumper module - This is a single jumper module that is set apart, up and to the right from the channel jumper modules on the circuit board. It provides a special function, when the jumper is set on the `-L' pins, the left bus signal feeding the left channel will be inverted. Note: A jumper MUST be installed at L BUS, R BUS, or L+R BUS, AND a jumper MUST be installed at NO VOL or USE VOL for the amplifier to operate. MONO APPLICATION (MEDIUM CURRENT) The ST55. 2's two output channels may be paralleled (mono) to combine the left and right channels output current. This feature allows the amplifier to double its apparent output current. To use, place the source group jumper for both channels on the `L BUS' jumper terminal. Place the volume group jumper for both channels on the `NO VOL' jumper terminal. The speaker output terminals on the ST55. 2's rear panel must be paralleled in order to complete the setup. [. . . ] Over time you may wish to clean the exterior of the unit by wiping it with a damp cloth to remove any dirt or dust that accumulates on it. Unplug the amplifier and be sure that it has completely powered down before you apply any damp cloth. Do not let any liquid enter the amplifier through the vents in the top cover. You may clean the connectors on the back panel with isopropyl alcohol annually. 10 SPECIFICATIONS Power Rating: 8 ohms 4 ohms THD (S+N) Frequency response Input sensitivity Input impedance Damping factor Current (peak to peak) Slew rate Dynamic headroom S/N (A-weighted) Voltage gain Line voltage Dimensions (O. A. ) Weight Power consumption 55 watts @ 1 kHz Not recommended 0. 09 % @ 1 kHz 5 Hz ­ 45 kHz 0. 77 Volts 33. 2 k ohms 100 20 Amps 14 V / sec 1. 4 dB 95 dB 28 120/220/240 VAC switchable 17"(w) X 12"(d) X 3. 75"(h) 23 lbs. [. . . ]