Tuesday, June 17, 2014

INFINITY BU-1 - SCHEMATIC - POWERED SUB-WOOFR

EXPLODED VIEW
SPECIFICATIONS
Driver è8"Woofer
Nominal Impedanceè4
Enclosure Design è Tuned Port
Amplifier Power è 50watts RMS
Frequency Response è 45Hz - 150Hz (± 3dB)
Crossover Frequency è 50to150HzContinuously Variable
Inputs
Line Level  è RCAjacks
High Level è (Speaker) Input terminals
Outputs è Full range Speaker
Sensitivity
Low Level è 50mV
High level è 1V
Input Impedance
Low Level è 10k
High level è 4.7k
Dimensions
Inches è 11½x11½x11½"
Metric  è 29.2 x 29.2 x 29.2cm plus 1¼" (32mm) for feet)
Auto Power
This Auto On/Off switch controls whether the BU1’s Automatic turn-on circuit is active. When the switch is ON, the BU1 will turn itself on, indicated by a green LED, when it is plugged in and receiving a signal. When the BU1 has not received a signal for approximately ten minutes, the unit will revert to the STANDBY mode, indicated by a red LED. When this switch is OFF, the unit will revert to the STANDBY mode and will stay OFF, regardless of input signal. THIS IS NOT
A TRUE AC POWER SWITCH AS IT DOES NOT DISCONNECT THE AMPLIFIER FROM THE 120VAC LINE.
High Level Inputs
These High Level Inputs are for receivers that do not have line-level “pre-amp out” or “subwoofer out” jacks. When a pair of main or satellite speakers are attached to the OUTPUT terminals, they are driven the full range of frequencies as generated by the music source (receiver, amplifier, etc.)
Low Level Input
These left and right Line Level Inputs are normally used when the receiver/processor has line-level “pre-amp out” or “sub-woofer out” jacks. If a single cable mono
or sub-woofer source is connected to the BU1, a Y-cable must be connected to the sub-woofer for full output.
Volume Control
This controls the volume level of the sub-woofer.
 Frequency
 The Frequency adjustment determines the upper corner roll-off point for the BU1.
{If a problem you are experiencing is a common (although not serious) one. It seems the "standby", or muting circuit for the BU-1 subwoofer is very sensitive. It senses any small voltage at either the low level or high level inputs as an input signal and will turn the unit on. This includes above-average DC offset on the customer's receiver/power amplifier, small amounts of 60 Hz hum or noise picked up by the customer's input cables, etc. Since the initial testing and development of the unit involved high quality audio equipment and connections, this tendency did not surface at that time.  The muting, or stand-by circuit electronically shuts down the bias voltages to the amplifier section. It does not turn off the unit's power supply. When the unit is idle it's drawing about as much power as a 17 watt light bulb, whether or not the muting circuit is activated. So the unit is electrically safe to leave turned on constantly no matter what color the LED is at the time, and of course sonically it's completely harmless.  This is not a serious problem.}
PRE-AMP SCHEMATIC
POWER AMP SCHEMATIC
230V_FEATURE
CLICK ON THE PICTURES TO MAGNIFY