The S90’s huge wave ROM hosts one of the most extensive voice libraries ever available in one keyboard. Here you’ll find some of the best piano sounds in the world, including a brand-new grand piano voice featuring three layers of stereo samples that switch dynamically according to how hard you strike the keys, for the ultimate in piano expression. Plus there’s an exhaustive selection of bread- and-butter sounds from the amazing MOTIF music workstation, including many of its popular electric pianos, strings, brasses, synthesizers and drum kits. And for those who want even more synthesis power, the S90 provides three expansion slots to add Modular Synthesis Plug-in System boards.
 

With three expansion slots for Modular Synthesis Plug-in System boards, the S90 is potentially four synthesizers in one! Offering new synthesis capabilities from FM to physical modeling as well as more polyphony, effects and multitimbral parts, these plug-in boards let you customize the S90 with the exact synthesis power you need, whenever you need it. The voice data for every plug-in board currently available is already stored in the S90’s ROM, so you’ll have a great selection of new sounds the moment you install a plug-in board.
 

Equipped with a USB-to-MIDI interface, the S90 is ready to connect to your USB-equipped Macintosh® or Windows® computer without the need for any additional hardware.
 

The S90 uses the same Balanced Hammer Effect (BH) keyboard as the MOTIF 8. Based on the Graded Hammer Effect keyboard found in Yamaha’s best digital pianos, this weighted-action keyboard provides an exceptionally smooth and realistic piano touch—yet, because it features an even balance from top to bottom, voices such as drums and synth basses will feel more responsive to your playing. And for even more performance expression, it also features aftertouch.
 

Not just a great synthesizer, the S90 also makes a wonderful MIDI controller. Equipped with four assignable data sliders, it provides extensive realtime control over external synthesizers. Plus four programmable keyboard zones let you create complex split and layered voice combinations using a mix of internal and external voices. Entire MIDI setups can be stored in User Performance memory and recalled at the touch of a button.
 

The S90’s realtime performance arpeggiator packs a wide range of patterns and styles, giving you musical inspiration at the flick of a switch. In addition to conventional arpeggio patterns, it’s loaded with an impressive array of musical phrases, including guitar strumming, drum grooves, keyboard riffs and more. Instead of trying to clone these performances with computer-generated algorithms, the S90 uses a more musical approach: It uses MIDI data recorded by real musicians. You can even program your own patterns and layer several arpeggiated voices together in a Performance.
 

The S90´s playback sequencer lets you play back standard MIDI files (format 0) directly from a SmartMedia™ card. Use this function to build up a library of up to 100 songs, any of which can be instantly called up at the touch of a button - great for live performance! Chain playback is also possible. The included File Utility software makes it quick and easy to transfer MIDI files from your computer to a SmartMedia™ card, so you can leave your PC at home the next time you do a gig.
 

Although loaded with powerful features, the S90 is surprisingly easy to use. Its intuitive user interface, centered on a 240 x 40 dot LCD screen and rotary encoder, lets you quickly navigate through menus and edit various settings. A Function Control matrix and four physical sliders give you instant access to and realtime control over part volumes, filter cutoff, effects, EQ and other frequently used parameters. And with the S90’s convenient Category Search function, pressing a button is all it takes to find the sound you’re looking for.
 

Yamaha’s new mLAN interface technology makes it possible to route all your digital audio and MIDI signals — both input and output — through a single, high- speed IEEE 1394 cable, greatly simplifying the process of connecting and configuring your digital musical equipment. Equipped with an expansion slot for optional mLAN interface boards, the S90 gives you access to this amazing music network technology.
 

For the power user, the S90 comes with voice editing software for Mac and PC, allowing detailed editing of voice parameters with point and click convenience. And if you want to try your hand at music composition, the bundled SQ01 Open Plug-in Technology*-compatible sequencing software for Windows® gives you everything you need to make full-fledged songs, including an Auto Arranger function for quick and easy song creation.
* Open Plug-in Technology is a newly developed software format that allows control over MIDI devices from software sequencers and other music software.
Note: The Windows® voice editor includes a stand-alone editor and a plugin editor for Open Plug-in Technology-compatible host applications such as SQ01 or Cakewalk´s SONAR™ 2.