The Electrumpet is an enhancement of a normal trumpet with a variety of electronic sensors and buttons. It is a new hybrid instrument that facilitates simultaneous acoustic and electronic playing. The normal playing skills of a trumpet player apply to the new instrument. The placing of the buttons and sensors is not a hindrance to acoustic use of the instrument and they are conveniently located. The device can be easily attached to and detached from a normal Bb-trumpet. The device has a wireless connection with the computer through Bluetooth-serial (Arduino). Audio and data processing in the computer is effected by three separate instances of MAX/MSP connected through OSC (controller data) and Soundflower (sound data). The current prototype consists of 7 analogue sensors (4 valve-like potentiometers, 2 pressure sensors, 1 "Ribbon" controller) and 9 digital switches. An LCD screen that is controlled by a separate Arduino (mini) is attached to the trumpet and displays the current controller settings that are sent through a serial connection.