This range can be divided into three constituent parts:
The K15e stands alone as a fabulous Indonesian-built, entry-level instrument, known for its impressively warm tone made possible by its solid spruce soundboard. Despite its compact size, it is able to produce a comparatively wide dynamic range.
The K200 and K300 mark the introduction of Kawai’s Millennium III keyboard action, making use of thermoplastic polymers and carbon fibre for the action’s smallest pieces, providing enhanced durability and reliability. These represent the best uprights to come out of Kawai’s Indonesian factory.
The K500, K600(AS), and K800AS are Japanese-built instruments that exhibit greater control, tonal complexity, and stability. These pianos are squarely aimed at proficient players and larger spaces, but are also recommended for those looking for a high-quality, long-lasting musical companion. Kawai doesn’t offer a top-tier upright piano that is also compact, so those with smaller music rooms may want to look at the options available from W. Hoffmann and C. Bechstein.
Common features of Kawai K-series instruments (from the K200) include the aforementioned Millennium III keyboard action, mahogany-cored underfelted hammerheads, tapered solid-spruce soundboards, soft-close fallboards, and a celeste pedal that muffles the sound of the piano - often referred to as a practice pedal. Models with the ‘AS’ suffix move the celeste pedal to a lever underneath the keybed to allow for a grand-style sostenuto middle pedal.