The Differences Between Grand and Baby Grand Pianos

Compare the Size, Tone and Quality of Different Grand Pianos

Close-Up Of Piano Strings
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The most obvious difference between a traditional grand piano and a baby grand piano is their size. Actually, there are many standard grand piano sizes, the exact measurements of which can vary by manufacturer or location. The following are averages of the most widely accepted across the globe:

Sizes of Baby Grand and Grand Pianos

   Concert Grand:9' to 10'(2,75 to 3,05 m)
   Semiconcert:7' to 7'8"(2,15 to 2,35 m)
   Parlor:6'3" to 6'10"(2 to 2,08 m)
   Professional Grand:6'(1,83 m)
   Medium Grand:5'6" to 5'8"(1,68 to 1,73 m)
   Baby Grand:4'11" to 5'6"(1,5 to 1,68 m)
   Petit Grand:4'5" to 4'10"(1,35 to 1,47 m)

Tonal Differences Between Grand Piano Sizes

The voices of the best baby grand pianos are nearly indistinguishable from those of larger grand pianos. However, this becomes less of the case as the size of the piano decreases. Many listeners notice the subtle difference between smaller pianos and larger pianos. 

The grand piano’s signature timbre is partially reliant on the length of its strings and soundboard (along with the quality and workmanship of these parts). Longer strings allow frequencies to resonate from a larger surface area, resulting in a more balanced, full-bodied tone.

Think of how a guitar string produces a bright, “clangy” tone when struck near the bridge, but sounds mellow and bluesy when struck in its center. This tonal spectrum widens as the string length increases; and as these extremes become further apart, more vocal elements are revealed between them. Because of this enrichment, the voice of a 9-foot concert grand piano is considered tonally superior to that of a baby grand piano.

At the same time, tonal superiority refers to acoustics, not personal preference. If you’re looking for a tone similar to that of a full grand, invest in a model of at least 5 feet 7 inches. Smaller horizontal pianos tend to have exaggerated timbres that can vary with dynamics, or even across octaves.

However, these characteristics, which may be off-putting to some musicians, remain celebrated by others for their colorful, eclectic displays of vocal originality.

Cost of a Grand Piano

Baby grands range in price and are typically much less expensive than grand pianos. The most expensive baby grand pianos hit the low price range of a regular grand piano. Full grand pianos span a wide price range, depending on the model, maker and year of manufacture. Since horizontal piano depreciation is slow, new and used grand pianos tend to stay around the same price range. See tips for buying a used piano if you are considering purchasing a used instrument. 

Tips for Buying a Grand Piano

  • If you opt for a baby grand because of its lower price, aim for the longest model possible. Cheap, mass-produced baby grands are surpassed in quality by some electric pianos, which cost thousands less.
  • Make sure your piano room will have the ideal temperature and humidity levels; the elements are especially dangerous to grand pianos because of their revealing lids.
  • The largest horizontal pianos take up about 63 square feet! If you plan to make such a purchase, take accurate measurements of doorways and stairwells, and throw in 2 to 4 feet of floor measurements for the bench.