Peavey 115P Volume Control Adjustment, Adjusting the kosmos Processing Level, High-Pass Outputs

Volume Control Adjustment

The Impulse 115P is equipped with a Master System Level volume control (6). When the Master System Level is adjusted fully clockwise‚ gain is at maximum and the input sensitivity is 0.375 VRMS for full-rated output. When this control is set half way up‚ gain is unity and 1.5 VRMS will drive the system to full power output. When driving the Impulse 115P from a mixer‚ it may be advantageous to reduce the input sensitivity by turning the volume control to the half-way point. At this setting‚ the Impulse 115P will more closely match a typical power amp input.

The amplifiers in the Impulse 115P are equipped with DDT. This unit also includes an LED (11) that illuminates when DDT is activated. This LED is located next to the Master System level. The DDT circuit will automatically reduce the channel gain to a level just slightly into clipping, guarding the speakers against the damaging high power continuous square waves that may be produced. Situations that may activate the DDT circuit include uncontrolled feedback, oscillations, or an improper equipment setting or malfunction upstream from the amplifier.

Always turn on any peripheral units before turning on the Impulse 115P. Also‚ make sure the Master System level is completely down (CCW) before turning the unit on.

Adjusting the kosmos™ Processing Level

The amount of kosmos processing is controlled by the Master System level knob. In order to achieve more sub-harmonic processing‚ turn the Master System level (6) up and the Level/Quake knob (7a) down.

When using the Impulse 115P with a passive‚ full-range speaker system‚ the relationship between the Master System level and the Quake/Sub level will determine the balance between the overall subwoofer output and the high frequencies that sent to the Left and Right speaker outputs. The amount of kosmos processing can not be controlled independently. It can‚ however‚ be bypassed using the Bypass switch (7c).

When using the Impulse 115P with a powered‚ full-range speaker system from the line level‚ high-pass outputs (8)‚ the powered‚ full-range speakers will usually have their own volume control. This will allow the high frequency level to be set independently. However‚ the kosmos Xpanse control (7b) for adjusting stereo spread‚ can only be adjusted at the Impulse 115P subwoofer.

High-Pass Outputs

These are low impedance‚ filtered outputs that are provided to send the high frequencies to a powered speaker or to a conventional power amp and speaker system. The output level is set by the Master System level control on the Impulse 115P.

The nominal polarity of these outputs is positive (pin 2) and can be run directly into most full-range‚ powered speaker systems.

If you experience hum or related ground loop problems‚ it might help to lift the shield ground on the balanced XLR cable at the Impulse 115P end. This can be accomplished via the convenient ground lift switch (10b) located underneath the High-pass output jack group. Check any input changes carefully. Always turn the volume control down before plugging and unplugging cables or switching ground lift switches.

Left & Right Outputs

These outputs will supply a full-range‚ 8 ohm minimum speaker system with a high-passed amplifier signal when using the Impulse 115P as a 3-piece system. The Xpanse control (7b) will expand the stereo sound stage and add high frequency processing to these outputs.

Impulse 115P: Subwoofer only (Add-on Use)

When using the Impulse 115P as a powered subwoofer only‚ run a full-range stereo signal to the inputs (5) or plug a mono signal into the Left input (5a) and engage the Mono switch (5d). The subwoofer will reproduce frequencies from approximately 45 Hz–120 Hz.

8