Companies starting with J

Jammy Instruments US (RnD64)

RnD64 is a product development company focused on IoT and connected hardware.

Jeff Whitehead Lutherie LLC

Innovative guitars and electronics for those who wish to reach new musical frontiers.
"Made by hand, by myself, for the love of the art and great music.".

Juce

JUCE is an open-source cross-platform C++ application framework, used for the development of desktop and mobile applications. 

The aim of JUCE is to allow software to be written such that the same source code will compile and run identically on Windows, macOS and Linux platforms. It supports various development environments and compilers.
JUCE also runs the Audio Developers Conference.