2.5mm DIY Stereo Plug Connector : ID 1798 : $1.95 : Adafruit Industries, Unique & fun DIY electronics and kits
10pcs Mini 3.5mm 3pole Screw Locking Stereo Jack 3.5 Audio Plug For Diy Soldering Wire Connector Silver - Connectors - AliExpress
Amazon.com: Audio 1/4" 90 Degree Right Angle Plug, 6.35mm Heavy Duty TS Mono Male Solder Jack Connector for Speaker/Guitar/Microphone Cables - 5PACK : Musical Instruments
How to Hack a Headphone Jack
Amazon.com: 12 feet 3.5mm 1/8-Inch Male Mini Plug Stereo Audio Cable : Industrial & Scientific
Amazon.com: Audio 1/4" 90 Degree Right Angle Plug, 6.35mm Heavy Duty TS Mono Male Solder Jack Connector for Speaker/Guitar/Microphone Cables - 5PACK : Musical Instruments
SpeaKa Professional Toslink Digital Audio Cable [1x Optical plug 3.5 mm - 1x Toslink plug (ODT)] 1.00 m Black | Conrad.com
3.5mm (1/8) Stereo Audio Plug Terminal Block : ID 2790 : $2.50 : Adafruit Industries, Unique & fun DIY electronics and kits