The Yamaha S90 is a professional-grade synthesizer designed to meet the needs of serious musicians and sound designers. First released in 2002, the S90 was a significant upgrade from Yamaha’s previous synthesizers, offering a wide range of sounds and advanced features that made it a favorite among professional musicians and studio producers.

One of the key selling points of the S90 is its keyboard feel. The keyboard is designed to simulate the feel of an acoustic piano, with weighted keys and graded hammer action that responds like a real piano. This makes the S90 an ideal instrument for pianists who want a synthesizer that feels familiar and comfortable to play.

In terms of sound, the S90 offers a wide variety of voices, including acoustic and electric pianos, organs, strings, brass, and more. Yamaha’s Advanced Wave Memory (AWM) technology provides high-quality samples that are designed to be both realistic and expressive. The S90 also features a built-in synthesizer engine that allows for deep sound customization, giving musicians the ability to sculpt their own unique sound.

The S90’s programmable controllers are another standout feature. The synthesizer includes knobs and sliders that can be assigned to control various parameters, such as filter cutoff, resonance, and envelope settings. This allows for on-the-fly adjustments and real-time sound manipulation, making the S90 a powerful performance instrument.

In addition to its sound and performance capabilities, the S90 is also designed for easy operation. The synthesizer features a simple interface with intuitive controls, making it easy to access and edit sounds without getting lost in a maze of menus and submenus.

The S90 also includes a SmartMedia playback sequencer, which allows musicians to record and playback their performances. This feature makes the S90 an ideal instrument for live performance, allowing musicians to create and playback their own backing tracks and accompaniments.

Overall, the Yamaha S90 is a versatile and powerful synthesizer that is ideal for professional musicians, sound designers, and producers. With its realistic keyboard feel, advanced sound engine, and intuitive interface, the S90 is a reliable and inspiring instrument that has stood the test of time.

Yamaha S90
Yamaha S90


The Yamaha S90 is a synthesizer that provides a perfect balance between a digital piano and a synthesizer. Its weighted keyboard action is one of the finest and best-feeling ones that you can experience on a synth. The mod wheels, real-time sliders, and pitch bend feature on the S90 showcase its synthesizer side.

The S90 offers 128 notes of polyphony (excluding the extra polyphony that one can add with any plug-in expansion boards) and well over 500 programs using the 228 MB high-quality waveforms driven from the AWM2 24 bit DSP chip. If you’re already familiar with the Yamaha Motif, you will feel at home with the S90ES. The S90ES keeps familiar menus, like voice, master, and performance modes, for modifying your sound settings. The sound banks for S90ES are remarkably similar in their structure.

Keyboard Feel

The Yamaha S90 is known for its excellent keyboard feel. It features the company’s famous Balanced Hammer Effect keyboard, which is designed to emulate the weight and feel of an acoustic piano. The keys are graded, which means they have different weights depending on their location on the keyboard, just like a real piano.

This feature makes playing on the S90 feel very natural and responsive, allowing for expressive playing and easy transitions between different playing styles. The keyboard is also velocity-sensitive, which means that the volume and tone of the notes played vary depending on how hard or soft the keys are struck. All in all, the keyboard feel of the Yamaha S90 is one of its biggest selling points, and a major reason why it is so popular among professional keyboardists.


The Yamaha S90 has an extensive library of high-quality sounds, with over 700 voices and 128-note polyphony. It includes a wide range of acoustic and electric piano sounds, as well as strings, brass, guitars, basses, drums, and many more. The S90 uses Yamaha’s proprietary Advanced Wave Memory (AWM) sampling technology, which provides a realistic sound quality and a wide dynamic range.

In addition, the S90 also features a number of advanced sound-shaping tools, such as a comprehensive set of filters, EQ, and effects. It also includes the ability to create and store custom user voices, making it a versatile and flexible instrument for a wide range of musical styles and applications.

Programmable Controllers

The Yamaha S90 comes with a set of programmable controllers, including pitch bend and modulation wheels, four assignable knobs, and two assignable buttons. These controllers can be used to modify and shape the sound in real-time, allowing for greater expressiveness and creativity in performances and recordings.

Additionally, the S90 has a comprehensive effects section that includes reverb, chorus, delay, and distortion, among others. These effects can be applied to individual voices or to the overall sound of the instrument, further expanding the range of sonic possibilities.

The S90 also has a built-in arpeggiator that can be synced to an external MIDI clock or internal tempo, providing rhythmic and melodic inspiration for improvisation and composition.

Overall, the programmable controllers and effects section of the Yamaha S90 make it a versatile and powerful instrument for a variety of musical contexts.

Simple Operation

The YAMAHA S90 is designed for easy operation, with its simple and intuitive interface. It features a large, easy-to-read LCD display that allows you to quickly access and adjust various settings and parameters. The instrument also includes a range of performance controls that make it easy to create and manipulate sounds on the fly, including pitch bend and modulation wheels, assignable knobs and buttons, and more. Additionally, the S90 features a comprehensive onboard arpeggiator and sequencer, making it easy to create complex, layered performances with ease. Overall, the YAMAHA S90 is an instrument that is both powerful and easy to use, making it an ideal choice for a wide range of musical applications.

Smartmedia™ playback sequencer

The Yamaha S90 features a SmartMedia™ playback sequencer which allows users to store and play back MIDI sequences and audio data using SmartMedia™ memory cards. This feature allows for easy storage and playback of music created on the S90, making it a convenient tool for recording and live performance. SmartMedia™ cards can be easily inserted into the S90 and accessed through the instrument’s interface

Other Features

For those who have an external sequencer, the S90ES can be used as a multitimbral tone generator. The REMOTE button is a handy feature that allows you to control sequencer software on your PC from the S90ES’s panel.

The S90ES also includes an arpeggiator with over 1700 styles, 3 slots for enhancing the S90ES sounds using the optionally available modular synthesis plug-in boards, and the mLAN16E board that effectively channels your MIDI and audio data to one IEEE 1394 connection, eliminating the need for lots of cables.


  • High-quality keyboard feel
  • Wide range of sounds
  • Versatile controller options
  • Smartmedia playback sequencer
  • Solid build quality


  • One drawback of the Yamaha S90 is that it lacks an onboard sequencer for recording.
  • The Yamaha S90 does not come with a switch pedal.


In conclusion, the Yamaha S90 is a high-quality professional keyboard that offers an excellent sound quality and realistic keyboard feel. Its extensive sound library, customizable controllers, and intuitive user interface make it a versatile instrument suitable for a variety of musical genres and applications.

However, the lack of built-in speakers and limited polyphony may be drawbacks for some users. Additionally, the size and weight of the keyboard may make it less portable than other options.

Overall, the Yamaha S90 is a reliable and powerful instrument that is well-suited for professional musicians and recording studios.