2.5 mm
Sub-mini Jack (TRS)
Invented in
1960s
Invented by
The phone-jack family
Availability
Uncommon
The smallest of the jack family, used for headsets, camera remotes, two-way radios and balanced earphone outputs on hi-fi players.
Technical specifications
FormatTRS / TRRS
SignalAnalog audio / control
Size2.5 mm
UseHeadsets, balanced out
Found on
headphones
Recommended brands
01Rean
02Neutrik
03Hosa
Where to buy
Europe-focused retailer searches. Some links are affiliate links and may earn a commission.
Fun fact
Audiophile portable players revived the 2.5 mm jack as a balanced headphone output, old size, new high-end purpose.
Tips & tricks
Easily mistaken for 3.5 mm, measure the diameter before buying a replacement.
Philosophy
Tiny enough to vanish into a watch or a walkie-talkie. The jack family’s smallest member, quietly useful for sixty years.
Applications
Pro audioInstruments
