Kurzweil K2500XS
The 88-weighted-key flagship of Kurzweil's K2500 line - the one that did double duty as a controller and a sampler in the same chassis.
Overview
Kurzweil's K2500 line was announced as a 1996 TEC Award nominee, and the K2500XS sat at the top of it. It had 88 weighted keys and full sampling capability. The standard K2500 and the K2500X were performance keyboards. The "S" suffix on the XS meant the sampling hardware was built in rather than optional. The K2500 series documentation lists the K2500S, K2500RS, and K2500XS as the models with onboard sampling. That is why the XS turns up in the rigs of players who needed to both play and capture their own material without adding a separate sampler to the rack.
The engine underneath is Kurzweil's V.A.S.T. - Variable Architecture Synthesis Technology. It is the same design approach that made the K2000 series a professional standard, and the company's own literature frames the 2500 series as building directly on that lineage. The front panel carries a fluorescent 64 x 240 backlit display. The operating system lives in flash ROM, so software updates load via floppy disk or over SCSI instead of by swapping chips. Sample memory tops out at 128 MB, and the machine ships with dual SCSI ports and a 32-track sequencer built in. An optional DMTi Digital Multitrack interface handles data format and sample-rate conversion for ADAT and DA-88 machines.
The control surface is where players tend to get attached to the XS. It has eight sliders and two ribbons, all mappable to any parameter for real-time control. Jordan Rudess, writing in EQ Magazine, described using the K2500XS as his master controller on the Rudess Morgenstein Project sessions. He singled out those eight sliders and two ribbons as the reason the real-time manipulation on that record was possible. The smaller ribbon can generate separate MIDI control signals from position and pressure, and the larger ribbon behind the keyboard splits into three control source sections. Sound on Sound UK (April 1996, p.92) covered the K2500 line as Kurzweil's new top-of-range keyboard. It noted the two-flavour approach - the semi-weighted 76-note standard model and the weighted 88-note X variant. The K2500XS takes that weighted action and adds the sampling hardware on top.
It was never a light or cheap thing to own. Mix (November 1996, p.267) ran Kurzweil's own advertising copy claiming the K2500 and K2500X were the ultimate performance keyboards with more standard features, control, expandability, and power than any other instrument at even twice the price. That is marketing, not a measured verdict. The same period coverage does confirm the feature set: 200 programs and 100 setups with 8 MB of Kurzweil's sounds, plus a disk carrying over 1,000 more, per Mix (October 1995, p.183). The K2500XS is a deep programming instrument that rewards time spent in V.A.S.T. It does not hand you its best sounds on the first pass.
The XS shows up in real working rigs in the period literature: Clint Black's project studio listed a K2500XS among its keyboards and controllers, and Jon Butcher's Brothers West studio ran a K2500XS rack alongside a Roland JV-2080 and Alesis QS8. That is not a museum piece in the making — it is a tool that was bought to do sessions and kept because it kept doing them.
The case against it is the same as the case for it. The 88 weighted keys and the sampling hardware make it heavy and expensive to move. The display and menu architecture assume a programmer's patience. The flash-ROM operating system means a unit with a corrupted OS needs floppy or SCSI access to recover, which is not a dealbreaker but is worth confirming before buying a used example. Samples and programs live on floppy and SCSI media, so a buyer should expect to source or rebuild a library rather than inherit a plug-and-play sound set. The K2500XS is not the easiest vintage Kurzweil to own. It is the one that lets a single keyboard be the master controller, the sampler, and the sequencer in a working setup.
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