49 MINI Keys (C1-C5) -[Orchestra Sounds]- Organ, Piccolo, Trumpet, Violin, Saxophone, Oboe, Piano, Music Box, Harpsichord, Guitar, Synthe1, Synthe2

-[Sustain]- Sustain 1, Sustain 2

-[Multi-Menu Pages]- On, Melody Voice Variation (1), Melody Voice Variation (2), Melody Mixer, Chord Voice Variation, Bass Voice Variation, Custom Drummer, Custom Bassist, Music Programmer, Tape

-[Rhythmn Section]- Disco,16 Beat,Rock 'n Roll,Shuffle,8 Beat, Bossanova,Rhumba,Samba,Swing,Slow Rock, March,Waltz

-[Rhythmn Effects]- Start,Synchro Start,Stop,Fill-In,Beat Lamps, Tempo,Volume

-[Auto Bass Chord]- Single Fingered,Fingered,Chord Variation (1,2,3),Volume

-[Stereo Symphonic]- Chorus, Tremelo

-[Melody Plus]- Duet (2 Voices), Trio (3 Voices)

-[Transposer]- 1/2 Octave Up or Down

-[Other Controls]- Power Switch,Power ON Light,Master Volume

-[Auxialliary Jacks]- Headphones, Aux D.C. 9-12Volt In, Aux Out (L+R), Tape (In & Out)

-[Amplification Onboard]- 2W x 2

-[Speakers]- 2 x 9cm (3 1/2")

-[Rated Voltage]- DC 9 Volt (6 x 1.5V 'C' Sized Batteries) YAMAHA PA-1 Adapter (Center Positive) Required. -[Dimensions]- 24" x 8" x 2"

-[Weight]- 3.0Kg (6.6 Lbs.)

Ok we are talking 1983 here; an ancient, yet interesting oddity. Probably the most interesting features on this model are: -Synthesizer. Very limited, but you are able to change Attack & Decay. -Multi-Menu This Scroll-wheel idea was pretty ingenious for its time. It allowed Yamaha to offer more features, without cluttering up the Control Panel with too many buttons. There are 12 buttons that are re-used for each of the 10 Menus. Thats like having 120 buttons on the panel! Amazing for its time. I believe this 'Multi-Menu' idea was first employed on MK-100, and would later appear on the Yamaha MC, MR, ME, HE, HC, HS, HX, EL & ELX Electone instruments.

The MK-100 is Digital, and features another unique feature. To back up your custom-created voices, it offers a 'To/From Tape' interface. This feature would also appear on many Yamaha keyboards, synthesizers & Electones from the 1980's. Using a cassette tape recorder (or even now, any digital recorder) you can transfer Customized Voices (or patches) out & back into the MK-100. It takes a LONG TIME to load data, even minutes. Still, the fact that it even had such a feature, is impressive.

Though it only had 12 sounds to begin with, The Synthesizer feature allows you to alter, and mix sounds, creating hundreds, if not thousands of variations.

There is no Touch-Sensitivety or After-Touch in MK-100. There are no MIDI ports either.

I would not reccommend this keyboard for live performance, but it can be fun to play with it in a studio, where it can still offer a Retro-80's flavour.

Very Limited by todays home or Pro Standards, but always worth something to the curious, who like to explore older instruments.

sounds-wise i prefer the 80s casiotone / sk style, it's a little too thin for my liking, but with a bit of tweaking you can get some lovely cheesy 80s lead sounds [think les rhythmes digitales]. the multi function 'toilet roll' selection system is superb, it has to be seen to be understood, it's a really innovative and easy way of entering and changing data. also, it features programmable bassline and drums. the bassline is great - when using auto-chord accompaniment it'll transpose the baseline and even shift notes about [eg flatten any 3rds if you're playing a minor chord]. you can save your edits onto tape, like a spectrum or c64 or something. if you don't then when you next access the noises they'll be random with nutso, junglist style drums - mmm.

good for new order / axel f / lrd style sounds

bad for realistic bassoons / handclaps / bongos

good for £0.

only complain is the drum section, if they'd asked me, I could have given them a better interface (plan, that is) ;) oh, and it 'clicks' a bit when ever you press a key, or something like that.. but it doesn't matter.

I won't get rid of it, ever..

+ The user interface, with its tremendous "function roll", and the "function keys" below, so smart. + The superb design of the keyboard, especially at this time + The very flexible architecture.

I can't really remember the specs... but you had poor drums you could, nethertheless easily access on the main "roll" to edit your patterns, and you could also edit the VCA env for the 'synth' sounds according to preset shapes and waveforms too. A real beast for the beginner I was. Chorus & also tremolo, I think, etc... To put it in a word, this lovely machine was FAR more creative than its market's concurrents, and I wish I could try it again today, just to see if it blows my 2080 on the analog pads, who knows ? Of course all of this has to be reported to what can be expected from this kind of very old keyboards, from the analog era. But I remember having be so fascinated by the sounds; this machine started it all : I became a synth addict then.