1: 0dB INPUT: Connect your bass here if it has �normal� pickups and no active electronics. This sends a full strength signal into the amplifier. If your bass has active electronics or high output pickups, or if the amp sounds like it�s distorting try the -15dB Input (#2). 2: -15dB INPUT: Connect your bass here if it has active electronics or high output pickups. The output signal will be attenuated by 15dB to keep it from overloading the amplifier�s input stages. 3: GAIN: This serves as the input signal level control, allowing you to set the amplifier for the best signal to noise ratio. 4: CONTOUR SHAPE: This control is only active when the Contour Active switch (#5) is pressed in. The setting of this control shifts the frequency where the contour effect is centered, giving you a wide variety of tonal variations, from a studio �V�-shaped tone to a more �live�, more present sound. 5: CONTOUR ACTIVE: When this pushbutton switch is pressed in the Contour Shape control (#4) is activated and the sound of your bass is affected by the setting of the control. Pressing the switch in a second time releases it, deactivating the Shape control. 6: LOW: Adjust the output level of your low-bass tones with this control. The center position is �flat� (no boost or cut). Turning the control to the left reduces the output level of the low frequency tones; turning it to the right increases their level. This control allows a 28dB range of boost or cut at 60Hz. 7: LOW MID: Adjust the output level of your lower midbass tones with this control. The center position is �flat� (no boost or cut). Turning the control to the left reduces the output level of the lower midbass tones; turning it to the right increases their level. This control allows a 15dB range of boost or cut at 400Hz for the BX-25; 150Hz for the BX-50. 8: HIGH MID: Adjust the output level of your upper midbass tones with this control. The center position is �flat� (no boost or cut). Turning the control to the left reduces the output level of the upper midbass tones; turning it to the right increases their level. This control allows a 18dB range of boost or cut at 1kHz. 9: HIGH: Adjust the output level of your high frequency overtones with this control. The center position is �flat� (no boost or cut). Turning the control to the left reduces the output level of the high frequency overtones; turning it to the right increases their level. This control allows a 33dB range of boost or cut at 10kHz.
10: MASTER LEVEL: The output level of the internal speaker, headphone jack and extension speaker are governed by the setting of this control. At the full left position there will be no output; rotating the control to the right increases the output volume level. 11: LIMIT: When a power amplifier reaches maximum output levels it may begin to �clip� its output signal which generates potentially speaker-damaging distortion. The BX-25/50 has a special APM (Automatic Power Maximizer) limiting circuit which helps minimize this problem by monitoring the power amplifier�s output signal, keeping it below clipping. This feature insures you that the sound from your amplifier remains clean and pure even at full power. The APM indicator will only light when the amplifier is near clipping; flashing at peak playing levels is acceptable, however if the light remains on constantly reduce the Master Volume until the light flashes. 12: HEADPHONES: For private practice sessions, plug a pair of stereo headphones into this jack. The internal speaker is disconnected whenever headphones are being used. 13: EXTENSION SPEAKER: You may connect the BX-25/50 to an external speaker with a rated impedance of 4 ohms or more using this jack. The internal speaker is disconnected from the amplifier when the Extension Speaker jack is used. WARNING: DO NOT attempt to use headphones in the Speaker jack! Permanent hearing damage could result! 14: ON LED: The word �ON� will glow when you turn the amplifier on showing you that the amplifier is activated and ready to play. 15: POWER: This heavy duty rocker type switch is used to turn the amplifier ON in the up position, OFF in the down position. The ON LED (#14) works with this switch as a visual indicator. 16: POWER CORD: (Rear panel, not shown) This heavy duty, grounded, three wire power cord is to plugged into ONLY a safely wired, grounded 120 volt, 60 cycle AC power outlet. DO NOT attempt to defeat the ground connection of this cable! If your BX-25/50 was purchased outside of the United Stated, see the unit�s rear panel for its power rating and follow the above guidelines.
