Kurzweil K150

Kurzweil K150 Image 2

The Kurzweil K150 is a truly unique and professional digital additive synthesizer rack-module. It is big, not just in size but power and creative potential. It features real time additive synthesis with 240 oscillators, 16 voice polyphony, upwards of 240 oscillators and extensive programmability. The K150 implements a unique editing method in which you mix, combine and alter the 150's 22 resident voices and 69 preset programs. You basically manipulate sounds on a harmonic level for creating various new timbres. The keyboard is can be split into 3 regions and capable of up to 7 layers. With extensive layering effects and abilities you can get some thick and unique sounds. There's 186 patches for memory storage and you can get up to 255 when you remove the installed sound blocks or overwrite presets.

The Fourier Synthesis (FS) is an upgrade to the standard K150 which allows you to define new instrument models by editing their velocities and envelopes, tuning intervals and more further expanding creative and unique sound synthesis potential. The FS model needs to interface with an Apple IIe to use Kurzweil's Sound Laboratory software for editing and management in order to unlock the true power and potential of the K150-FS. The oldest versions of this software is called SOUNDLAB, while the newer ones are called .S.M.P. (Sound Modeling Program). The results of this program are stored in the K150 as voices, which can be utilized in up to seven layers of any of the three regions in any given program.

Everything is modifiable and controllable about this synth. Pitch bending, vibrato, EQ, chorusing, polyphonic after-pressure and full 16 channel MIDI implementation with almost everything being MIDI controllable. However, for as big and powerful as the 150 is, its sound generally seems to be a little thin, due to its digital nature. There is no user-controllable filter. Merely a low-pass anti-aliasing filter, which cuts off at around 9 to 10KHz, with the slope becoming noticeable at about 7-8 KHz. Overall it's a wonderful synth but requires considerable knowledge to operate well compared to most synthesizers.

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4 Visitor comments
November 1, 2011 @ 2:39 am
I just found and bought one of these after a long, long wait. I'm trying to collect every unusual or unique sound making machine there is. Name one other synthesizer with 240 oscilators. I have a Kawai K5m and a K5000W, and Native Instruments' Razor. Steve Burke, thanks for the tip on the IIgs; much better than a IIe. Even with simple software, melding 240 waves into new sounds is going to be a trip. This is a synthesis god-box. Maybe I'll write my own software for controlling the K150 using modern computing power.
Steve Burke
December 3, 2009 @ 11:34 pm
I have two of these units so that I could produce stereo effects. The latest SMP (sound Modeling Program) is 2.41 . It is better to use an apple gs because you can use the mouse to move envelopes around. Having two units makes the chorus work great, being it was designed with the midiboard in mind it will respond to polyphonic aftertouch, which you can use to change the pitch or delay. it sounds magical in stereo with 3 voices per note. It still have noise in the soft velocities on the piano do to the way the envelopes work on the synth. It uses a compounded 10 bit word for producing sound as compared to 16bit linear. You still get the dynamics of 96db but the noise floor is not linear which is why one hears it on theis synth. I won't trade for the world though. I wish someone would make a softsynth using the algorithms it has. I'm not to the job.
June 26, 2009 @ 12:12 pm
Just bought one. The piano sound is pretty incredible for a 1986 non-pcm machine but not so useful today. The percussive sounds however are quite useful. I've been layering this with other keys and the effect is stunning. No real filter here but all those OSC. Programming with the LCD is a bear and I am only scratching the surface with regard to my understanding of this beast. I’m looking for an Apple IIe. I don't think there is any other software available for the K150 (if anyone knows differently, please post). The owners manual is on the Kurzweil site. Regarding service, the most knowledgeable person is Hal Chamberlin. As a first impression, I’m happy with this synth and am looking forward to exploiting its potential. Its also cool having a piece of equipment in the studio that looks like it was pulled off a Soviet era nuclear sub. The downside is I may need to participate in a cap and trade emissions program for all the energy it consumes. Wendy Carlos has used this synth.
May 2, 2009 @ 1:23 am
I once saw one of these (and played on it) on the Frankfurt Music fair some time in the 80's. I remember the piano sound especially as it sounded so real. I seem to remember that they has stuffed it full, mainly with acoustic sounds.The great thing about the K150 was that is used live harmonic (fourier) synthesis, with which I mean that it used no samples but everything was generated as you played, which makes it much more alive than a sample based synth. You could call it the big brother of the Kawai K5. The K150 synth was incredible for the periode and was kind of the predecessor of acoustic modeling synths of today.
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  • Check Price
  • The link above will take you to an eBay search for this synth to see active listings. If you don't find it there, try looking in our forum marketplace or post a wanted classified.
  • Specifications
  • Polyphony - 16 voices
  • Oscillators - 240 osc! (sine and noise)
  • LFO - Yes
  • Filter - DCF (Digitally Controlled Filter)
  • Envelopes - 256 stage DCA envelopes
  • Keyboard - None (rackmount)
  • Memory - 186 patches (up to 255)
  • Control - MIDI (16 parts)
  • Date Produced - 1986
  • Resources & Credits
  • Found image on Ebay.

    Thanks to Arthur W. Green for supplying some information.

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