Sound
U-shaped
Also called U-shape, gentle V
A U-shaped tuning lifts the bass and treble a little and leaves the midrange only slightly recessed, so it keeps the energy of a V-shape without pushing voices as far back. Many well-regarded consumer tunings are U-shaped.
The difference from V-shaped is one of degree: the midrange dip is shallower and broader. Vocals stay present, and the result works across more genres.
Reviewers use the term loosely, and one person’s U is another’s mild V. The Frequency response graph settles it faster than the adjective.