TRN CS4

The CS4 is presented as an ultra-budget IEM with very modest hardware and pricing. The reviewer notes that it can sound harsh out of the box, but with a simple modification it becomes more listenable and competes reasonably well for its price.

This review describes the CS4 as a low-cost earphone that can be enjoyable once adjusted, but not especially polished in stock form. It is praised for strong treble energy, acceptable detail, and surprisingly decent imaging and soundstage at its price.