Hey guys i was wondering if this its possible to add midi to an amp. The one in particular the Orange Dark Terror. If it is possible what would i need to make it possible, maybe a layout or schematic of what i'm doing. And if i took it to a pro what it would cost me in total roughly. Thanks.
What are you trying to accomplish with adding "midi" capabilities to your Orange amp?

Are you trying to use a midi controller to change channels?
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Its only a single channel amp I want it so I can create presets among the one channel.
That sounds difficult. And expensive.
You could do it. But it wouldn't be easy and it wouldn't be worth it.
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I'm not entirely sure how to integrate a MIDI controlled device into the amplifier itself.

I read that Neil Young uses a device he calls "The Whizzer", which physically turns the knobs on his Fender Deluxe to stored positions. It's not as neat as midi channel switching, but it works. Considering your amplifier only has 3 knobs, you could build a similar contraption. You could use an Arduino to control 3 hobby servos to turn the knobs.