how do most stompboxes behave when there is DC power connected, e.g. via a wall plug, but no instrument cable is plugged in? Are they active or not?
I know that most stompboxes are not active if they are run using the battery and if there's no instrument cable plugged in. This can be implemented by using a stereo jack for the instrument input so that the battery can be disconnected from ground when no cable is plugged in.
I'd also like to completely disconnect the battery when the DC plug is connected. For that I use a DC power jack with an additional contact switch that can be used to disconnect the battery if the DC plug is plugged in.
I now wonder how most stompboxes behave if the DC plug is plugged in but if there is no instrument cable in the input. Put into a table my situation is as follows:
Code: Select all
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| DC Jack Connected | Instrument Connected | Result |
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| - | - | No power is drawn from the Battery / FX off |
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| - | X | Power drawn from Battery / FX on |
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| X | - | ? ? ? |
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| X | X | Power drawn from DC Jack / FX on |
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Thanks for any help!