SPS-1 Operating Instructions - Rear Panel

(Click on rear panel for larger photo)

Input: An XLR-type balanced input used to connect the Preamp Module or an External Mic.

Input Mode Switch: This switch is used to split the 'Ring' signals from a two pickup preamp module to Channel 2. With the switch 'out', the two signals (e.g. pickup/internal mic or pickup 1/pickup 2) are blended together into Channel 1. By pressing this switch, the two signals are separated, and the 'ring' signal (e.g. the internal mic or pickup 2) is now processed by Channel 2. Use this mode when processing a two pickup instrument in stereo.

Phase Rev: Press this switch to reverse the phase of one channel relative to the other. This allows you to invert the phase of Channel 1 relative to Channel 2. In this way, you can listen to a pickup/mic or pickup1/2 combination in or out of phase with one another. The two combinations will sound very different, and one usually sounds a lot better.

Mic Switch/Mic Gain Trim: Press this switch only when using an External Mic. Leave this switch 'out' when using a Preamp Module, or when the XLR input is not in use. The trimpot directly above the Mic switch adjusts the gain for the mic preamp. Turn counter-clockwise for less gain (a vocal mic), and clockwise for more gain (acoustic guitar mic). Set this level so the 'peak' LED flashes occasionally.

Press this switch to supply phantom power to an external condenser mic, when using the channel as a mic preamp.

Line In: An unbalanced 1/4" pre -EQ input for using a channel with line level signals, such as a wireless receiver, a cassette or CD player, etc. The Line input remains active even when using the XLR input with an external mic or Preamp Module.

Insert: A mono effects loop for patching an effects device or volume pedal directly into a channel. Tip = Send, Ring = Return.

Channel Output: A TRS balanced direct channel output for sending the output of a channel directly to the board, a tape machine, a monitor amp, etc. This output is also switched on and off by the foot switch.

Stereo Effects Interface

Replace Switch: With the switch 'out' (the MIX mode) the stereo effects returns are blended with the dry signal in the preamp. Use this mode when using reverb or other effects you wish to run 'wet only' and combine with the unprocessed signal in the preamp. When the switch is pressed (REPLACE mode), the dry signal is turned off and only the signal passing through the effects loop is heard. Use this mode with a multi-effects chain, compressor, or other effects meant to replace the 'dry' sound.

Effect Send: A post-pan, line-level stereo send used to drive a reverb, chorus, or other true stereo effects device.

Effect Return: A post-pan, line-level stereo input for returning the effect output to the preamp. These inputs can also be used as post-EQ stereo inputs for combining a CD or tape player, drum machine, or synth with Channel 1 and 2.

Tuner Output: A channel 1 only signal for driving a tuner. This output remains active even when the preamp is muted by the footswitch, for tuning quietly.

Foot Switch: This jack accepts the stereo plug from the footswitch. Closing either the tip or ring to ground causes the 'On' or 'Loop' LEDs to be activated.

Monitor Output: 1/4" unbalanced Left and Right outputs for driving a stereo monitor amp or stage amp. Can be assigned to the stereo mix or Channel 1 only.

Master Output: XLR-type balanced stereo outputs for connecting to a snake, mixing board, tape machine, or other balanced input. Pin 2 is hot.

Gnd Lift: By pressing this switch, pin 1 of the XLR output connectors is lifted from preamp ground. Use this to avoid ground loop hum when connecting to a balanced input.

On/off rocker switch and ac input. Wired for 120V/60 Hz unless otherwise specified.