Doepfer A-151 Quad Sequential Switch (4HP)

Full Description

New Revision With Step Switch

The Doepfer A-151 Quad Sequential Switch received a revision in 2005, with brought a new Step switch to the module to provide even more flexibility. This three-way switch that can be found towards the bottom of the module's face plate can be used to switch between 2, 3, and 4-step modes. This switch determines at which step the module will revert back to the first I/O. For example, if you have the switch set to 4, the module will operate as it did prior to the introduction of the switch, cycling through steps 1 to 4 (1, 2, 3, 4, 1, 2, 3, 4 etc.). However, if you to it to 2 or 3, it will revert back to the first step after reaching the step determined by the switch. Set to 2, the module would cycle through 1 and 2 (1, 2, 1, 2, 1, 2, 1, 2 etc.), and 3 would cycle through 1 to 3 (1, 2, 3, 1, 2, 3, 1, 2, 3 etc.).

Controls & Indicators

• Step Indication LEDs: Each I/O features a respective LED next to the socket. These LEDs provide you with visual feedback, enabling you to see which I/O is currently connected to the common out/input at any one time
• Steps Switch: Three-way switch that is used to limit the number of addressed I/Os to 2, 3, or 4

Inputs & Outputs

• Trig. In: This is the module's trigger input. Each new pulse (at the rising edge) switches the common O/I to the next I/O. After stepping to the fourth I/O, the next trigger pulse will send the common O/I back to the first I/O again. With an incredibly fast repeating trigger, such as a fast LFO, the A-151 can produce exceptional audio-frequency modulation
• Res. In: Allows you to override the stepping sequence, and send the common O/I back to the first I/O whenever a pulse is sent to the reset input. The rising edge of the pulse immediately resets the common O/I to the first I/O. Using this input, you can create repeated sequences which switch between three I/Os
• O/I: This is the common output/input for the A-151. It will output whichever I/O is currently active/connected to the common O/I (visible via the indication LEDs next to each I/O socket)
• I/O 1 to 4: These are the inputs/ouputs that are switched between when the module receives a trigger/reset input in the Trig./Res. In sockets

Specifications

• Width: 4HP / 20mm
• Depth: 35mm (Measured from the rear side of the front panel)
• Current:
  • +12V: +20mA
  • -12V: -10mA