Kurzweil K250

Edit links
From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Cmcgilton (talk | contribs) at 10:33, 22 September 2007. The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

The Kurzweil K250 a.k.a. "Kurzweil 250", "K250" or "K-250", manufactured by Kurzweil Music Systems was the first combined live performance and studio electronic musical instrument using sampled sounds from string, woodwind, brass and percussion instruments as well as sounds created by waveforms. Primarily designed for the professional musician, it was conceived by Raymond Kurzweil, founder of Kurzweil Music Systems and Stevie Wonder, twenty-two time Grammy Award winner, singer, songwriter and producer.

In 1982 Stevie Wonder asked Ray Kurzweil to solve two problems: How to bridge the world of musical composing to the world of electronic keyboards and if a musical instrument for both live performance and studio use could be created using acoustical sounds, saved in digital form and reproduced in analog form, very much like how an reading machine functions, converting analog speech to digital form and visa-versa, especially since Stevie Wonder uses these machines in his daily life living with blindness. So Raymond Kurzweil, a well-known developer of optical character recognition/reading machines for the blind made use of many technologies originally designed for reading machines and adapted them for musical purposes. A prototype of the Kurzweil K250 was first manufactured in 1983 for Stevie Wonder, complete with Braille buttons, controls and a vast array of functions with sampled musical instrument sounds as well as synthesized sounds to choose from so Stevie Wonder could interact and use the keyboard (during the production of the Kurzweil K250 at least five machines were manufactured for Stevie Wonder).

Many of the acoustic instrument sound sources found in the Kurzweil K250 (as well as the Kurzweil K1000 and K1200 series keyboards) were played by members of the Boston Symphony. The Kurzweil K250 was presented during the 1984 Summer NAMM trade show to unparalleled accolades. Shortly thereafter the Kurzweil K250 was commercially manufactured until 1990 and was available as an 88-key fully-weighted keyboard and as an expander unit without keys called the Kurzweil K250 XP. A few years later into production a rackmount version called the Kurzweil K250 RMX also became available.

The Kurzweil K250 astounded the musical world with its ability to create realistic sounds of acoustical instruments. More astounding at the time was that it could play up to 12 notes simultaneously (this is also known as 12-note polyphony) both individually and using layered sounds (playing multiple sounds on the same note simultaneously, also known as being multitimbral). Up to that point in time the majority of electronic keyboards utilized synthesized sounds and emulated acoustical instrument sounds created in other electronic instruments using various waveforms produced by oscillators. It is worthy to note at that time five other manufactured digital sampled sound musical instruments were available: E-mu Corporation's E-mu Emulator and E-mu Emulator II; Fairlight Corporation's Fairlight CMI; and New England Digital's Synclavier I and Synclavier II. However there were major differences between the Kurzweil K250 and these other instruments:

  • The acoustic sounds contained in and produced by the Kurzweil K250 were so realistic tests were conducted with listeners blindfolded to differentiate sonic differences between a 9-foot grand piano playing and the Kurzweil K250 playing. Both were played through the same high quality $40,000 US Dollar sound system. No differences were conveyed. This despite the fact that the sounds in the Kurzweil K250 are 10-bit sampled sounds and utilized a proprietary sound contouring model to reduce memory requirements. Nevertheless this was a quantum leap forward in electronic keyboard musical sound that has never looked back since.

  • Multiple units could be connected together (in a daisy chain fashion) and played simultaneously with new technology at the time called MIDI - Musical Instrument Digital Interface. Not only was it possible to have a musician play the Kurzweil K250 as a solo, band or musical ensemble instrument; it could also be played as an entire band or even as an entire symphony orchestra! Since the Kurzweil K250 could produce twelve notes simultaneously and if twelve Kurzweil K250's were connected together for example, one could play 144 notes simultaneously, more than any symphony orchestra could produce simultaneously with all members playing at any moment in time. MIDI could also be used to transmit and receive other messaging in controlling the sound as desired.

  • SCSI technology is utilized in its system architecture, which was the fastest data transfer technology available at the time.

  • It utilized a Motorola 68000 32-bit 10MHz processor, which was also one of the fastest processors available at the time.

  • With the sampling option a sound could be sampled up to 50,000 KHz which is greater than any human can hear.

  • The pitch of a sound could be transposed (see: transposition (music)) up or down using five different transposition modes without any change in timbre.

    • The Kurzweil K250 was possibly over-engineered as well. For example, the J12 connector on the back of the Kurzweil K250 where the power pod connects to the unit is one of the same connectors used in the NASA Space Shuttle. This was likely incorporated to withstand the ruggedness of setting up and tearing down the instrument for performance. Other details, such as an array of multiple output options, a click track, a sync source, an analog output board that produced inaudible noise levels with the widest amplitude (see envelope (disambiguation)) available even at maximum volume and multiple sliders (see potentiometer) to assign multiple functions were all state-of-the-art at the time of production. The Kurzweil K250's starting cost at $10,715 plus options (in 1983 - 1990 U.S. dollars) put if out of reach for many musicians. The primary reason for the high cost was the fact that memory was very expensive during that time along with costs in designing, engineering, research and development of such a revolutionary product. Those who could afford the Kurzweil K250 enjoyed a musical composition, MIDI composition and performance instrument unparalleled to any other at the time. Even an Apple/Macintosh computer could be connected to the instrument for sound modeling and musical compositional purposes. Almost 4,000 units were manufactured. The Kurzweil K250 (with wooden keyboard) is heavy and bulky to move, it weighs 95 pounds (plus a few pounds for optional boards and components) and measures 54 inches length x 27 inches width x 9 inches height. The Kurzweil K250 is still used today by musicians in recording studios, movie studios, orchestras, ballet and theater companies (see ballet company), colleges and universities, Bell Labs (the research arm of Alcatel-Lucent), religious organizations, churches and Kurzweil K250 enthusiasts throughout the world.

    Technical Specifications

    • 12-track music sequencer, 12,012 events (except Expander units which offer 7,900 events), fully editable including quantization (see Quantization (music), section call, sequence chaining, punch-in/out, mute/solo/fader automation, event editing, channel stealing, rhythm change, tempo change, MIDI and tape sync.
    • Tempo control, plus or minus up to 700 beats per minute (can be additionally manipulated if using the on-board sequencer), real time.
    • Chorus (five different modes - doubling, full chorus, flanging, echo and microtonal) with delay and detuning capability (all editable and adjustable), switchable in real time.
    • Transpose (five different modes - octave pitch shift, chromatic pitch shift, octave transpose, chromatic transpose and timbre shift) maximum range of 2 octaves up to 5 octaves down depending upon the mode selected, real time.
    • Fine Tuning (center position is concert pitch A=440), real time.
    • Brightness (of the sound), real time.
    • Sound volume, real time.
    • Volume swell, real time (see Expression pedal).
    • Tremolo, real time.
    • Vibrato, real time.
    • Sound velocity, both positive (increase) and negative (known as reverse velocity), real time (see keyboard expression).
    • Yodel capable (see Yodeling), real time.
    • Aliasing, real time.
    • Pitch bend, up or down, real time.
    • Touch sensitivity, real time.
    • Two sustain modes, normal sustain and sustained release (which is a quick dampening of sound after a note is struck), real time.
    • 96 non-destructive ROM sounds (basic sound block).
    • 341 presets.
    • 12 voice polyphony, 12 oscillators per voice, 256 segment amplitude envelope generator.
    • 16-bit multitimberal, 144 parts.
    • Fully assignable filters and envelopes.
    • 2 Low-frequency oscillators (LFO's) per voice, 24 multi-form LFO's total, all adjustable, 12 different adjustable options (see Low-frequency oscillation).
    • Variable sampling rate.
    • 18-bit floating point resolution.
    • Truncation, looping (see music loop), velocity crossfading.
    • Two separate signal buses (see electrical bus).
    • SCSI system architecture.
    • Separate outputs on both balanced XLR and 1/4 inch high and low power signal outputs as well as a 1/4 inch headphone jack.
    • Click track (built in metronome) for timing purposes, switchable on or off.
    • Trigger in via 1/4 inch jack.
    • Two full-size brass pedals built into the power pod (Typically used for sustain and sound dampening just like an acoustic piano).
    • Full size 88 note velocity-sensitive fully-weighted keyboard using lead weights in the keys (excluding RMX models).
    • Keyboards can be split, layered or set up with dual-amplitude. 87 split keyboards in one keyboard setup is possible. Approximately 40 user-created keyboard setups can be programmed, depending upon the keyboard types that are programmed.
    • MIDI capable IN, OUT and THRU with limitations on MIDI functionality (not MIDI GM standard - GM standard was implemented in 1991, one year after the Kurzweil K250 ceased to be manufactured).
    • Kurzweil K1000 remote mode capable with message display and remote button operation.
    • Weight (main unit without power pod) = 95 pounds plus a few pounds for optional components.
    • Size = 54" width x 27" length x 9" height.
    • Power input 110-120 volt or 220-240 volt. Some units had selectable voltage.

    Manufacturer Optional Components

    • Sampler: 16-bit sample rate of 5kHz to 50kHz, 100 to 10 seconds of sampling time respectively. Six different sampling modes: Quick Take, de-emphasis, slow decay, normal decay, fast decay and speech. Samples are fully editable. 1MB ROM standard. 1/4 inch microphone input jack for sampling source.
    • 4 MB SuperRAM (increases the sampling ROM available).
    • Sound Block A - a.k.a "Expanded Basic Sound Block" (adds an additional 88 non-destructive ROM sounds).
    • Sound Block B - a.k.a "Rock Sound Block" (adds an additional 59 non-destructive ROM sounds).
    • Sound Block C - a.k.a "Orchestral Sound Block" (adds an additional 43 non-destructive ROM sounds).
    • Sound Block D - a.k.a "Horn Sound Block" (adds an additional 35 non-destructive ROM sounds).
    • Separate output board (providing twelve 1/4 inch jack discrete monolithic outputs in addition to the polyphonic stereo outputs). See Monophony and Polophony.
    • Plexiglas sheet music stand.
    • Performance (tubular) keyboard stand.
    • Daughterboard for installing up to two additional ROM sound blocks beyond the capability of adding four sound blocks.
    • QLS Modem Board - Apple Macintosh computer interface for saving/loading of samples, setups, keyboards, sequences and bins using QLS (Kurzweil 250 Quick Load System) or MacAttach software (predecessor to QLS software).
    • QLS (Kurzweil 250 Quick Load System) software up to version 3.8 for use with an Apple II computer or any compact Macintosh computer (Macintosh 512 up to Macintosh IIci) computer using Mac OS 6 - 7.5 for use in uploading/downloading information to/from the Kurzweil K250 and working with that data. The data could also be viewed and/or manipulated using other third party software.
    • QLS cable for connecting the Apple/Macintosh Mini-DIN 8 port to the Kurzweil DB-37 computer jack (Mini-DIN 8 Male to DB-37 Male).
    • Battery-operated RAM cartridge and cartridge adapter kit for data storage and retrieval.
    • Hyper Kurzweil K250. Very little is known about this model other than the RAM cartridge was relocated to the left front panel, the right front panel had other functionality (unknown), five additional buttons with some sort of SCSI functionality were placed above the tuning control, 88 red LED's (Light-emmitting diodes) were placed above each key and the slider caps were different. It is suspected this may have been one of the last Kurzweil K250's developed.

    Third Party Optional Components

    • Apple II computer or nearly any compact Macintosh computer (Macintosh 512 up to Macintosh IIci) computer using Mac OS version 6 - 7.5.
    • MacAttach software for use in uploading/downloading information to/from the K250 (this was superseded by QLS, which was available optionally by Kurzweil Music Systems). The data could also be viewed and/or manipulated using other third party software.
    • Sweetwater Sound Block SW800 - a.k.a. "Sweetwater Orchestral Sound Block" (adds an additional 54 non-destructive ROM sounds).
    • Sweetwater Sound Block SW900 - a.k.a. "Sweetwater Contemporary Sound Block" (adds an additional 52 non-destructive ROM sounds).
    • Various sampled sounds were available via the "Sweetwater network" that Sweetwater Sound established in the mid to late 1980's for the purpose of creating and swapping user-created sounds. Some of those sounds were incorporated on the Sweetwater SW800 and SW900 Sound Blocks.
    • Sweetwater Sound K250 Editor Librarian software. Required QLS and a separate MIDI interface from the K250 to the Apple/Macintosh computer.

    Undocumented Functions

    • Mono Pressure - If the K250 is connected to a MIDI device that is not using the Rock/Pop General MIDI standard, this function can control the volume of that MIDI device independently of any other MIDI device connected using the Rock/Pop General MIDI standard.
    • Channel Stealing - If the parameters for Stealing Ahead and Stealing Before Notes are set to 11 apice it is possible for the Kurzweil to produce more than 12 notes simultaneously despite the fact there are only twelve analog channels available.

    Notable Kurzweil K250 Users With Articles on Wikipedia

    References

    • Sound on Sound - Size Does Matter Kurzweil K250 Workstation Keyboard (Retro) [1]
    • Sound on Sound - Synth Secrets [2]
    • Kurzweil 250(Precursor to the 2500) - Innovative Digital Synthesizer [3]
    • Biography of Ray Kurzweil [4]
    • Additional Article of Ray Kurzweil with picture of Stevie Wonder [5]
    • The Age of Spiritual Machines [6] or [7]
    • The Man and the Machine:An Interview With Ray Kurzweil [8]
    • Virtual Organ - Virtual Instruments:Joe Barron, Present at the 1984 NAMM Show when the Kurzweil 250 was introduced: [9]
    • What's New In Electronic Music; The Art Advances At Warp Drive: A. Arnold Anderson, New York Times [10]
    • JSTOR: Computer Music Journal: Vol. 10, No. 1 (Spring, 1986), Pages 64-86 [11]
    • Synthony's Synth & MIDI Museum [12]
    • Indiana University (USA) Don Byrd - Synthesis of Sound Microsoft Powerpoint Presentation[13]
    • Wikipedia article sampling (music)
    • Wikipedia article Sampler (musical instrument)
    • Mastering the Kurzweil 250, Volume One: User's Guide and Volume Two: Reference Manual, Copyright 1988 Kurzweil Music Systems, Inc. [14]
    • Synrise - Brief information on the Kurzweil 250 (In German) [15]

    Audio

    • The Virtual Kurzweil 250 Sound Sheet - Play the 45 RPM Kurzweil 250 Demo Record virtually![16]
    • The Kurzweil 250 Rock Block - Play the 45 RPM Kurzweil 250 Demo Record virtually! [17]
    • The Kurzweil Rocks! - Play the 45 RPM Kurzweil 250 Demo Record virtually![18]
    • Christopher Yavelow - Countdown (For the Nuclear Age) - The Worlds First Computer Opera, completely synchronized from the baton of the conductor to the Kurzweil K250[19]
    • Christopher McGilton - Religious/Sacred Music in .mp3 format performed on the Kurzweil 250 and Yamaha MU-50/80 Sound Module [20] or [21]
    • Jane Brockman - Kurzweil Etudes excerpts in the tradition of Chopin performed on the Kurzweil 250, in three series:[22][23][24]
    • Jeff Roach - 58 Hours For Jessica Song (written about Jessica McClure who fell in a Midland, Texas USA well on October 14, 1987) [25]
    • Steven Johannessen - Music Showcase at the Middle Of Nowhere [26]
    • Pamela J. Marshall - Spindrift Recordings - Noises, Sounds & Strange Airs, "Child's Play"[27]
    • Pauline Oliveros - Dear.John: A Canon on the Name of Cage[28]
    • Craig D. Tollis - The Happy Frog: Kurzweil K250 - Two demo recordings of the Kurzweil 250 [29]

    Audio and Video

    • Keith Emerson - Emerson, Lake and Powell with Paul Schaffer and the CBS Orchestra on the Dave Letterman Show (Note that two Kurzweil K250's are being played live - one by Keith Emerson and the other by Paul Schaffer)[30]

    External links

    Retrieved from "https://en.wikipedia.org/w/index.php?title=Kurzweil_K250&oldid=159574175"