Our Rating Method — Le Diapason

Every grand piano we evaluate receives a rating out of 5 stars, calculated from a proprietary grid of five criteria. This rating is not an average of opinions gathered online: it is the result of a structured assessment that combines the manufacturer’s official technical specifications, the field experience of pianists, and our own instrumental expertise.

Our five criteria

Criterion Weight What we assess
Sound quality 30 % Projection, harmonic richness, evenness across registers, sustain
Action / touch 25 % Responsiveness, double escapement, regularity, repetition
Build / craftsmanship 15 % Care of manufacture, material quality, durability
Value for money 20 % Price positioning against the segment’s direct competition
Versatility 10 % Suitability for studio, stage, home and teaching

The overall rating is the weighted sum of these five criteria, rounded to one decimal place and expressed in stars. The weighting is identical for every instrument assessed: whether it is a Yamaha, a Steinway or a Blüthner, the grid stays the same, ensuring consistent comparisons.

Our sources

Our evaluations rest on three pillars: the manufacturers’ official technical specifications, a synthesis of feedback from pianists (specialist forums and musician communities — always rephrased, never reproduced verbatim), and our own expertise in keyboard instruments.

When the available data is insufficient to assess a criterion reliably, we prefer not to assign a score rather than put forward an unfounded figure.

Transparency

Some links in our reviews may be affiliate links: if you buy through one of them, we earn a commission at no extra cost to you. This will be clearly stated and compliant with regulations once the programme is active. It never influences our ratings, which are established solely according to the grid above.