Amp Selector FX Router

BYOC Amp Selector FX Router. With this pedal, it's possible to route your instrument to more than one amp, or effects loop. It's even possible to output your instrument to more than one amp simultaneously. Ground lift transformers are available in the pedal as well to minimize ground loop hum than can occur when an instrument is plugged into more than one amp simultaneously.

Thermionic Studios has purchased this kit to build this pedal. We are in the process of building the pedal and will have more to report upon completion.

Controls

• Switch 1 - "Transformer 1 Isolation Switch":
• Switch 2 - "Transformer 2 Isolation Switch":
• Switch 3 - "Phase Inversion for Output B":
• Footswitch 1 - "Both/One":
• Footswitch 2 - "A/B":

General Information

http://byocelectronics.com/ampselectorinstructions.pdf

Switches

Footswitches:

- The A/B footswitch selects/toggles between Output A and Output B
- The BOTH footswitch turns on both Output A and Output B simultaneously.

Transformer isolation switches:

- Switch A: This switch toggles the transformer for Output A on and off.
  Switch flipped to the left is ON; flipped to the right is OFF.
- Switch B: operates exactly the same as Switch A, but for Output B.

Operation

If you plug an instrument cable into:

• Input A without anything plugged into Input B then the pedal will send signal to both Output A and Output B.
• Input A while also having a cable plugged into Input B, then the pedal will only send signal to Output A.
• Input B then the pedal will only send signal out to Output B

If you wish to use the Phase Inversion switch please consult table below:

Switch Indicator	Instrument Access	Output	Phase State
off	Input A	Output A	IN PHASE
off	Input A	Output B	IN PHASE
off	Input B	Output A	NOT AVAILABLE
off	Input B	Output B	IN PHASE
on	Input A	Output A	IN PHASE
on	Input A	Output B	OUT OF PHASE
on	Input B	Output A	NOT AVAILABLE
on	Input B	Output B	IN PHASE

Phase Inversion

Our review of the schematic draws us to conclude that the BYOC Amp Selector and Stereo FX Router does not invert phase.

Electronic Part	Action	Phase State
IC1a	Does not Invert	Original
IC1b	Does not Invert	Original
IC2a	Does not Invert	Original
IC3a	Does not Invert	Original
IC3b	Does not Invert	Original

This will have to be born out by testing and observation.

However, many on the BYOC board forums have looked at the Amp Selector/FX Router and suggested an interesting option: If it wouldn't be helpful to use the remaining half of IC2, and some of the remaining empty pads on the PCB in order to set up a switch that will toggle the phase inversion of the audio signal through output B to make it either in-phase, or out-of-phase.

Here are a few threads on the byoc boards discussing the phase inversion switch:

http://www.byocelectronics.com/board/viewtopic.php?f=52&t=44330

http://www.byocelectronics.com/board/viewtopic.php?f=12&t=32756&hilit=amp+selector+phase

As this appears to be possible, we will be implementing the phase inversion switch for Output B for our pedal. Here's how to use it:

Phase Inverter switch
Switch Indicator	Instrument Access	Output	Phase State
OFF	Input A	Output A	IN PHASE
		Output B	IN PHASE
	Input B	Output A	NOT AVAILABLE
		Output B	IN PHASE
ON	Input A	Output A	IN PHASE
		Output B	OUT OF PHASE
	Input B	Output A	NOT AVAILABLE
		Output B	IN PHASE

Pedal Manual

As of this time, BYOC has not issued a separate manual on how to use the pedal. The best reference is either this wiki page, or the instruction manual (linked above in General Information) at Buildyourownclone.com which describes the architecture of, and how to build the pedal.

Schematic

© Copyright 2011, BYOC LLC.

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