Kurzweil K2500 (1996)
Kurzweil's follow-up to the K2000 doubled the polyphony, doubled the sample RAM, and answered nearly every complaint owners had about the original.
Overview
The K2000 was a computer that happened to have keys. The K2500 pushes that idea harder: 48 voices of polyphony, up to 128 MB of sample RAM, and a base model with an exceptional 76-note semi-weighted keyboard. Sound On Sound (1996) covered the K2500's VAST synthesis architecture and Object hierarchy, along with the doubled polyphony and sample-RAM ceiling. That review also noted the K2500X variant, which swaps in the fully weighted 88-note keyboard found on the PC88, and the sampling option that turns the instrument into what the magazine called "one of the best sound-design machines on the market."
The K2500 came in three versions: the 76-note K2500, the 88-note weighted K2500X, and the rack-mount K2500R. All three can take the sampling option and three sound-expansion ROM Blocks. Electronic Musician (May 1996) priced the base K2500 at $4,960, the K2500X at $5,520, and the sampling option at $842. That is flagship-workstation money.
The base instrument includes 8 MB of sample ROM, and the same 8 MB ROM Blocks from the K2000 carry over. The daughterboard that holds those blocks now also carries a 4 MB stereo piano sample. A good piano is often the first thing players audition on a workstation, and this one gives the K2500 a serious one out of the box. Electronic Musician (May 1996) described that 4 MB piano as "stunning."
Effects on the base K2500 still run through the original DigiTech processor inherited from the K2000, but the effects themselves are completely revoiced. Owners who wanted more could add the KDFX custom digital effects chip for $895, which Electronic Musician (May 1996) reported as "available soon" at review time. The same review flagged the DMTi digital multitrack interface at $1,495. It moves digital audio to and from the K2500 over AES/EBU, S/PDIF, Alesis ADAT Lightpipe, and TASCAM TDIF. The last two were the formats that mattered if you were tracking to a DA-88 or an ADAT.
The K2500 really pulls away from its predecessor as a controller. Electronic Musician (May 1996) singled out two well-implemented ribbon controllers, eight programmable control sliders with mute/solo buttons for each Zone, and two fully programmable buttons near the pitch and mod wheels. The magazine called the result "one of the best master controllers you can get."
Software updates moved to Flash ROM on the K2500. System software and ROM Objects can be updated from floppy disk, where the K2000 required swapping chips. Electronic Musician (May 1996) called this approach "far superior" to the chip-swapping it replaced.
The architecture underneath is VAST - Variable Architecture Synthesis Technology - the same system that made the K2000's reputation. Setups can include up to eight Zones instead of three, and the Setup editor was completely overhauled.
Kurzweil's own advertising billed the K2500 as "Award Winning/State-of-the-Art Synthesis/Sampling/Performance Keyboard Technology," and the company leaned on its "non-obsolescence by design" pitch. At one point it gave K2500 owners the KB-3 organ mode free as part of that commitment. Electronic Musician (May 1996) closed its review with the plain verdict that the K2500 is "a smokin' synth that provides just about everything you need to make beautiful music," and named it an Editors' Choice winner for the year.
Buyers should confirm which version they're looking at (76-note, 88-note weighted, or rack), whether the sampling option and ROM Blocks are installed, and whether the Flash ROM has been updated. Those determine both capability and price far more than cosmetics.
eBay Listings
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.