” Teenage Engineering OP-1 Keyboard Synthesizer – Rev. 2, bought in 2019-2020. $899 OBO
Custom Firmware is installed that can be read about here : https://github.com/op1hacks/op1repacker
This enables you to add or change the software running on the OP-1. With this, you have the an added synth engine, iter, a new filter effect, and the cow effect is now a moose. Basically it makes an already fun instrument even more fun! All this can be reversed as well, if you wish.”
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