Difference between S4R and other models

S4R 1.3 version is acoustically identical to the 1.2 version but with the USC calibration plugin included. This improves their flat frequency response from ~2dB down to ~1dB tolerance using DSP.

S4R tuning was developed with clarity in mind. That is to deliver accurate monitoring for recording and podcasting sessions. Mids-forward tuning is welcomed in monitoring for details and dynamics. Both of these are crucial when you’re recording instruments or vocals at the highest level.

The S5X are specifically tuned for spatial audio mixing with a brighter character that helps with 360 positioning and movements of 3D binauralised audio (e.g., Dolby Atmos). They are also open back, so not comparable with the S4R.

Regarding S4R vs S4X tuning, the S4X are slightly darker sounding and warm. They represent how a common room will sound. That, together with acoustics properties, makes them a staple in over 10,000 studios worldwide for mixing and producing in stereo.

Keep in mind, the S4R are a closed back design to provide isolation and tuned to provide required level of clarity for monitoring when recording instruments and vocals or podcasts.