G-Major / G-Major 2 / G-System: How to make channel switching work

Question

How do I connect the G-Major / G-Major 2 / G-System to my Amp for channel switching?

Answer

Printer friendly PDF version of this answer available for download on this link.


Please note the following:

Because of the sheer amount of different amps and implementations of channel switching on the market, the TC Support Team is not able to advise you regarding custom cabling for channel switching with your particular amp.

Therefore, if we don't have any schematic available for your amp, please get in touch with the manufacturer of your amp, and refer them to this information. They should be able to tell you the extent of compatibility between the TC channel switching implementation and your amp.

Please note that the G-System has 2 Switching outputs; the G-Major / G-Major 2 has only 1. 


Guitar amplifiers using a TRS stereo jack input for channel switching and i.e. reverb or channel boost.

If the footswitch delivered with your amp has two buttons and a TRS stereo jack, just obtain a stereo patch cable and connect the G-Major/G-System Switch Out to the Footswitch or Remote in of your amp.

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Guitar amplifiers with separate (mono) jacks for channel switching and for i.e. reverb or channel boost.

A "Y-split cable" will, in most situations, make it possible for you to switch channels and/or reverb on these amps.
-If the footswitch delivered with your amp has two buttons and two mono jacks, just obtain Y-split cable and connect the G-Major/ G-System Switch Out to the Footswitch inputs of your amp.

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Guitar amplifiers with a multipin connector for the footswitch input.

Many amplifiers use multipin custom connectors for the footswitch. These connectors are often DIN connectors that make them appear to be MIDI connectors, but they're not. These connectors are often used to gain space on the panel and also because they offer multipin connections where a TRS jack can only handle 2 pins (+ ground). In this case you must contact the amp manufacturer to get a description of the connections and make (or have made) a custom cable. Below is the description of G-Major Switching system (standard)

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Guitar amplifiers (eg. Bugera) employing momentary switching relays as opposed to latching (tip-to-ground) switching.

The G-Major / G-Major 2 / G-System relays are latching (not momentary)  relays (tip-to-ground) which will ONLY work with similar relays at the other end.

Likewise, TC Electronic is unable to advise you with regards to building a "workaround", either by way of of a DIY project or by way of modifications to the product (which would void the product's compliance with applicable safety and emissions standards.) for these type of amplifiers, you'll need to use a dedicated switching device. Many of these units offer both momentary and latching relays and can be controlled via MIDI.

Possible artifacts at channel change  

Please note that G-System relays can take 30 ms to switch, and with some amps that could generate possible artifacts (apart from the latency). Some amps use 1 relay per channel (i.e. some Mesa Boogie)  and can be in a status where 2 channels can be on for a very short period (a few ms) that can result in a sudden jump of volume. Damping the strings will minimize it as a workaround, but it's unlikely that you will be able to to switch seamlessly while playing. 


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