Musical Keyboard Features  and Definitions

Arpeggiator = Many home keyboards come with a function that allows them to create arpeggio patterns and chording patterns in the rhythm style you select. Often, all you need to play is one note and the keyboard will build the entire chord. 

Effects = The sounds the keyboard makes can be embellished with studio effects such as reverberation, echo, delay, chorus and more. 

GM or General MIDI= An industry standard map of sounds. For example, the first set of sounds are pianos, followed by synthetic pianos and so forth. The quality of the sounds varies from keyboard  to keyboard, but the sounds are numbered in the same order. This allows for MIDI files to keep their instrumentation.  Keyboards have more " sound banks, so they are not limited to the 128 sounds in the GM map.

I/O = The connectivity of the keyboard. Almost every keyboard has MIDI in and out, but if you're buying a really cheap one, check to be safe. Many keyboards can connect to computers in many ways, including through a USB cable.       

Memory = There are two types that are relevant. The first is the amount of sound,  or  wave memory. A keyboard with a larger memory usually will have higher quality sounds and more of them. The second type of memory relates to keyboards that record MIDI or audio. That feature tells us how much recording memory there is.   

Multi-Timbral voices = Sounds that are built from more than one instrument. For example, a piano and strings combination is an often used multi-timbral sound.   

Number of keys = A piano has 88 keys. Higher end keyboards also have 88, but 61 is the standard amount. Some keyboards only have 49 or less, which makes playing piano sounds difficult as you run out of notes. Those keyboards are better for instruments with a more limited range, such as guitars. 

Polyphony = The amount of sounds a keyboard can play simultaneously. Older keyboards had limited polyphony, which created an unpleasant chopping sound on suspended notes. Nowadays, keyboards commonly allow 32 to 64 voices to be playing at the same time.     

Rhythm pattern = An onboard drum machine. A feature usually found on consumer keyboards, although professional keyboards are incorporating more advanced sequencing and rhythm functions. 

Sequencer = Some keyboards have their own MIDI sequencer. This allows you to record your playing and play it back at will.   

Synthesizer = Technically a machine that artificially creates sounds. All  the atmospheric pad sounds and synthetic instrument sounds are synthesized. The realistic sounds are sampled, which means they are created out of recorded instrumental playing. 

Touch response sensitivity = The ability to play the note louder or softer depending on how hard you press on the key.