Yamaha makes everything from acoustic pianos, upright and grand, to lightweight, portable digital keyboards. The Yamaha NP-31 is in the latter category, finding a nice balance between quality and convenience.
The feel of a piano keyboard, digital or acoustic, is always an important factor to consider. The NP-31 is equipped with a “graded soft touch” keyboard, which is designed to simulate the feel of a real-life piano, with all of its hammers and strings. This means that the keys should have a similar weight and resistance to those attached to actual hammers on acoustic pianos and that the digital keyboard responds to velocity of the user’s fingers (ie. how heavy or soft one hits the keys). While this Yamaha model has both, less expensive digital keyboards more often than not have less realistic weight and velocity-response.
While the NP-31 does not have a prolific number of features and settings, the ones that it does have are useful and well-designed. For instance, the keyboard has 10 preset voices of commonly used instruments. So, other than the typical grand piano sound, the user can toggle through and replicate other keyboard-based instruments such as pipe organ, harpsichord, and electric piano. In addition, the settings also allow the user to layer two different instruments on top each other, creating dozens of unique sound possibilities. The NP-31 also provides 10 preset songs, a MIDI in/out, four types of reverb, as well as a built-in metronome. It also includes a feature called AWM Stereo Sampling, which is probably the instrument’s most advanced feature. AWM allows the user to sample and import outside sounds into the keyboard and use keys to trigger these samples.
Portability is one of the biggest selling points for the Yamaha NP-31. Described by the company as “slim, light & compact in design,” the piano weighs just under 13 lbs (6kgs) and is less than 50 inches (105 cm) in length, which is a fraction of the weight and length of even the most basic acoustic pianos. In addition to the AC power adapter, this digital piano also has a battery power option, taking only 6 AA batteries, which allows for approximately 6 hours of playing time. And, with a stereo pair of built-in speakers, it is possible to set up and play just about anywhere.
If there are any drawbacks to the NP-31, it would be that the keyboard only contains 76 keys, as opposed to the standard 88 keys of a full-range piano. This means that the six highest and six lowest notes are cut out. Technically, however, because there is a built-in transpose option, the missing notes can be recovered, but still the user will never have access to all 88 notes at the same time. And although the stereo pair of speakers is a nice feature, the speakers themselves are only 6 watts, which is really only suitable for playing alone. If one wished to perform to an audience or practice with a band, an external, more powerful speaker is necessary.
Overall, the NP-31 by Yamaha is ideal for those looking for a high-quality digital piano with which to start practicing seriously, but don’t want to spend their entire paycheck. It’s also perfect for already serious players, who are seeking something more portable, but don’t want to lose the feel of a real-life acoustic piano.