1. 0dB (INPUT): The signal output from an instrument (active or passive) or a line level signal may be connected here by means of a shielded instrument cable. 2. 15dB PAD: This switch, when depressed, attenuates the input signal by 15dB. Attenuation allows the Gain control (#4) to be used over a larger portion of its range. If clipping is indicated with the Gain control near minimum, attenuation is needed. 3. PEAK LED: This LED flashes when the signal level into the preamp approaches clipping. Adjust the Gain control (#4) until a strong signal from your instrument causes this LED to flicker. NOTE: If the LED flashes frequently with the gain at a low setting, use the 15dB Pad (#2) to attenuate the input signal and readjust the Gain. 4. GAIN: This serves as the input level control for the amplifier. For the best signalto-noise ratio set this control so the Peak LED (#3) flashes when you strike a string fairly hard. 5. BASS: This is the primary low frequency control which allows for 8dB of cut or boost at 50Hz.
6. ULTRA-MID: This is the primary midrange control. Rotate the control to the left of center for a �contoured� sound (more distant, less midrange output) or to the right of center for a pronounced (more upfront) tone. 7. TREBLE: This is the primary high frequency control which allows for 12dB of boost or 19dB of cut at 5kHz. 8. MASTER: Set the overall output level of the amplifier with this control. The Effects Loop and Balanced Out (#19-21,24) are not affected by the Master control. 9. LIMITER: The B2/B2R uses an internal Optocoupler Limiter to assist in keeping the power amplifier�s output �clean� at extreme volume levels. (All amplifiers begin to clip their output signals as they approach maximum output levels, resulting in distortion which may damage your speakers.) To engage the Limiter, depress the Limit switch. Whenever the amplifier is at full power, the adjacent LED will flash. This is an indication that the limiter is keeping peak signals from clipping the output. NOTE: Playing at full power with the Limiter off will give you increased output power, but the sound may be distorted. Use discretion when playing without the Limiter.
10. EQ ON SWITCH: Depress this switch to activate the Graphic EQ. The adjacent LED illuminates when the EQ is on. 11. GRAPHIC EQ: These sliders control the output of the frequencies indicated above each control. The center position of each control is flat (no boost or cut). 12. POWER ON LED: This LED indicator illuminates when the POWER switch (#13) is ON. 13. POWER SWITCH: This heavy-duty rocker switch applies the power to the amplifier. The amp is ON when the top of the switch is depressed, OFF when the bottom of the switch is depressed.