Official Store
This is the official listing for the Fosi Audio IM4, the $100 single dynamic “open-back” style IEM I reviewed in the video. It’s a warm, bassy, non-fatiguing set with tip and nozzle options that actually let you experiment with the tuning.
Pros
- +Warm, smooth V-shaped tuning that’s easy to listen to
- +Deep, satisfying bass with strong mid-bass slam
- +Includes multiple tip sets and swappable nozzles for tuning
Cons
- -Removable nozzles can undo themselves
- -Not a highly technical or super resolving IEM
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Official Store
Available on Fosiaudioshop
External purchase
Highlights
- +Warm, smooth V-shaped tuning that’s easy to listen to
- +Deep, satisfying bass with strong mid-bass slam
- +Includes multiple tip sets and swappable nozzles for tuning
Recommended by
Late Night Unboxing