1, 3: LEVEL: These rotary potentiometers control the
level or gain of each channel, with the fully-clock-
wise position of each providing maximum sensitivity.
2, 4: PRESENCE: These rotary potentiometers add
emphasis to the upper frequencies, giving increased
“presence” to the output.
5: POWER SWITCH: This switch turns the amplifier
on and off. When AC power is applied to the ampli-
fier the switch will light up.
SPA-200 Rack Mount Power Amplifier