Kurzweil K2500XS

It's a little hard to pick up at first. The manuals are overly technical. Editing patches is easy but try to understand KDFX

I wrote Jordan Rudess an e-mail about the keyboard when I first got it. (No, Jordan Rudess is not a friend of mine although I do think he is one of the greatest players out there. I got his e-mail from his website) He wrote me back saying just max it out. He was right. Get all of the memory, all of the rom cards, don't forget the kdfx, a good scsi cd rom and zip drive so you can load samples and save your own setups. THe options on this keyboard are truly endless. I used this keyboard mostly for my cover band and I run sequences with integrated samples. Never a problem.

I recently retired the Kurzweil and I've tried to recreate my live performance on a Korg Triton Studio and a Yamaha S90 (same sounds as the Yamaha Motif) Together, these two keyboards can't recreate the sounds of the Kurzweil. There really is no other way!!!

I have a Triton Studio, I have a Yamaha Motif (and an S90). I wanna start by saying that Triton is a great workstation, but the sounds don't even come close to the Kurzweil. Yamaha sounds are pretty good, but not as good as the K2500. I have a saying. Yamaha/Triton sounds real good, but Kurzweil sounds real.

That being said, if real sounds are what you're worried about, there really is no other option. The stock sounds are great. The pianos are awesome. The strings are completely unmatched by any other keyboard out there. I'll put the KB3 organ simulator up against any dedicated organ unit out there. This keyboard basically sounds like what ever it sets out to sound like at any given moment. Every Sound is crystal clear.

Warning:The keyboard action is deep and takes some getting used to

This is my problem. First off, do not buy one without purchasing a road case with wheels on it. I think that's why you see so many PC88s on the road. No one wants to lug this big heavy thing anywhere. I've had all kinds of problems with my pitchbender too. It would send my keyboard out of tune. In the end, I ended up disabling it. It just seems like it doesn't travel very well.

I wrote e-mails to their tech department and got responses within a few hours.

Kurzweil sounds are the best out there. In terms of performance, no other keyboard will offer a greater library of sounds. The only problem in performance is the fact that this thing is BIG and HEAVY. I've just recently decided to buy a K2661 which, if it has all the sounds,effects and options of the k2500 without the size, should be completely unstoppable.

v.3.02 Brilliant I do not have the new KDFX option but even without it, kurzweil has a winner. The best sounds I have ever heard in an instrument. So many options and choices when editing programs. recomended for synthy players that require that "Styx" feel with edgy synths and other creative sound. Manual is one inch thick and very detialed excellent. Impressive board, best I have played.

Action varies from board to board however mine happens to be fabulous. Effects are terrific but KDFX are better. Too many MIDI capibilities (not). Endless features with eight easy to use sliders for fast tweaking. sequencer is easy to use but "it is no Cakewalk" (no pun intended). HOWEVER NEW BOARDS etc. are a hassle to take to a dealer and let them install.

Instruments are by far, THE BEST IN THE WORLD. Well for any music. Effects on mine are mediocre but than again I don't have KDFX. It reacts to your playing any way you assign it to. Ridiculously flexible.

I'm only 15 and I just got one hopefully it will do well when I go gigging. Onely downside is no pro musicians use one on the road. (Maybe that's just because at 72-some pounds it takes a crew to carry it.) :)

Company is friendly and fast over the internet but the company is hard to get upgrades and cards shipped to your local dealer. (Tip: Order the part, wait the three or so weeks then take your board in to have it installed.) It's not all Kurzweil's faught though.

Yes, Yes, Yes Terrific. I would say that I would, now, in 2004 buy the newer K2600XS instead of this, but duh, right. This is a great professional board. Awesome flexibility and great overall. The room for growth is tremendous and makes music fun. this is a workhorse no doubt. Even if your not pro, if you have $7,000 to throw down on a board you will have the SECOND greatest board ever, (second only to it's brother the K2600XS) KURZWEIL makes an incredible board with limitless features and pristine sounds.

Kurzweil is avery arrogant company. If it weren't for Dave Mash's endorsement of their early models at Berklee, who purchased truckloads of their product, we may have all been spared their existence.
What few redeeming qualities Kurzweil products may possess they are overshadowed by the exhorbitant price tag which quite often get cut drasticaly, by retailers, to move product.I purchased a full blown 2500 XS 88 key version as my master controller in my MIDI suite for the fact that it had extensive realtime control sliders for MIDI and that it would read Roland samples. Out of all the patches, only the Rhodes noteworthy- one of the best I have heard to date. The drums and imitative sounds of all types were a joke, very synthy, dark, and undefined.
The expansion boards are all terrible and overpriced. The programming inane and completely different from any other manufacturer.

For a unit of this expense and hype the polyphony was very limited, the sequencer is a TOTAL joke!The effects are plastic sounding. Expanding should be done by a pro- cause the unit requires a brain surgeon ( with lots of time and $ to burn ) to upgrade. Kurzweil had the nerve to advertise a fully blown "Pro" version for $20,000- gee I bet they sold a lot of these!
The Keyboard assembly is made by Fatar- not a bad feeling action but hardly reliable. I have yet to speak to one Fatar owner who has not had problems.The only saving grace to the 2500 is the MIDI implemtaion and controllers which are excellent.It's interesting to note that when computers had been used for sequencers for over a decade and there were several stand alone sequencing units and other powerful workstations, that Kurzweil was bragging about their "13,000 note polyphony" on thier $6,400 unit!

The sounds are all dark and unusable aside from the Rhodes. The effects plastic and lame. The keyboard, when it worked, was very good.

To navigate on this unit live or in the studio would be rediculous if time was of concern to you. It's very heavy to move and when I took the keyboard assembly out for repair I noticed just how aweful the internal design was.

Soon after I bought the 2500 I purchased a copy of the Take 6 CDROM I heard at Namm. Problems: the entire CD was not license-free, It took me over an hour to figure out how to load the sounds, and the outdated and obscure DOS oriented OS is slower than Bush capturing Osama.

If it were stolen I send a note of condolence to the thieves.
I really hated it was so painfuly slow reading 3rd party samples and was rediculous to upgrade but mostly the sounds are simply aweful! Programming, with all of their inane and pretentious language, kept me from enjoying the unit I had spent as much as my car on.

Very sophisticated but completely strightforward to understand.
Menus and sliders etc. the best i've come across in a workstation

Serious amount of features:
Sample&Synthesis at the extreme. Sound design algorithms to the nth degree
Master Keyboard options are fantastic.

keybard action is excellent, even in 2004. The shouds are astounding. A Rolls Royce is a Rolls Royce, and this instrument is equally timeless in its quality.

Only own a month (Feb 2004). But it was sold 2nd hand to me in pristine condition and even the keyboard action is perfect. What you'd expect from Kurzweil.

Shockinglg good. Kurzweil UK and Denmark have emailed me several times and i know i can still upgrade to all options (internal HD, ROM boards, KDFX etc) and they will help in every way possible. I own about 40 synthesizers and this is my first Kurzweil. They are my future - I'm a complete convert because of the shocking quality of this instrument and Kurzweil support (and I own and receive good support for a propher T8, two CS80s, a VL1, two SY99s, 2 SY77s and five JD800s, so Kurzweils support in Europe are THAT good (and iI live in ireland)).

I will be buying a second one for my new project studio to be built in 2006.

Way too heavy to carry around to gigs, the thing is a beast. Well written manuals, but very complicated piece of equipment in general. Endless key punching at times to get where you want to be.

Really excellent set of features and sampling. On board sequencer was top notch. MIDI remapping was really powerful, the whole VAST architecture can do many many things.

Suffers from the same basic limitation that all samplers do, the fact that you're working with a sample and they can only be stretched/processed so far. The fact that all the controllers are remappable creates a unique bit of expressibility.

Utterly undependable. Power supply is incredibly sensitive. The pitch bender went crazy at a couple live performances. It would lock up when left on overnight. At times it would just do crazy things altogether and have to be reset from scratch. Eventually the power transformer shorted to ground and the thing gave me a jolt. It came with a bad scsi board and without paying through the nose to get a new scsi board I couldn't get a hard drive installed.

Kurweil was not helpful, other than an email "take it to a licensed technician". Great, that was only a four hour drive away.

Between not being able to carry it around, having a performance screwed by random pitch bending, and then it shocking me-- I sold this piece at a big loss (after getting a new transformer put in). I feel so @#$@^%, I will not purchase Kurweil music products in the future.

Using OS 4.03, have been using the machine for a little over two years. Technically, the machine is pretty straightforward. The manual is well written, and the OS lends itself to experimentation and learning as you go.
Physically, this is a VERY difficult machine to work with because of its size. I find myself not bringing it places because it is so big and heavy, and the thing won't fit in the back of any standard cars.
If I could do it all over again, I would get the K2500RS rather than the K2500Excess

Keyboard action is excellent, but the tradeoff is in incredible weight (see previous section). Built in effects are your standard Digitech multieffects, which are great sounding for built in effects. The onboard sequencer is a bit clunky . . . I never use it other than to load sequences I've made on my computer for live use.

Some of the built in sounds are pretty cheesy, especially the drum sounds. But with this machine, there is no excuse for using cheesy built in sounds because you can load any sample and make any sound you want!
Velocity and aftertouch response is excellent . . . sometimes aftertouch is even TOO sensitive (but that can always be fixed by toning down the amount aftertouch will affect the sound)

I've never had a problem other than with a bad piece of memory (which was not Kurzweil's fault, and the music store I bought it from replaced it promptly). I've opened the unit, installed sample RAM, and closed it back up an hour before a gig withour breaking a sweat (other than when I was trying to lift it!) I've heard from friends who work in repair shops that K2500s are second only to ADAT's in frequency of repairs, but after more than two years with mine, I've never had a problem.

I've called with technical questions at times in the past. You will probably not get through to a live person, but you can leave a message and know that someone will call you back later that day or the next day. Email support, courtesy of David Fox at Kurzweil, is excellent, with prompt replies and thorough anzwers.

As I previously stated, if I coulld do it all over again, I would have gotten a K2500RS and a separate controller. However, if you aren't planning on taking the thing around, it is nice to have an all-in-one unit with excellent keyboard action and several continuous controllers.
Polyphony and maximum amount of sample RAM lacks a bit when compared with Emu or Akai samplers, but I have never run against problems because of this. They are a bit overpriced, but you will not get a better, more powerful machine for ANY amount of money.

software 2.1 version. Very hard to use at first. The key board is not user friendly at all. Quick access banks are easy to use and makes things better. This keyboard takes time to learn but it is time well used when you get the hang of things. Not for your weekend keyboard player. This keyboard is for the ones who want to sound the best and will take the time to learn how to do so.

Feels very close to a real piano (as close as you will come). The only keyboard that feels more like a piano is the Yamaha P-200 but that board is just for piano and is very limited unlike the K2500XS. The effects are the best I have found on a keyboard but that doesn't say much. The best in the world when it comes to MIDI capabilities. No more to say about MIDI because there is no limit to its capabilities. Love the KB3 organs which are as close to having a b3 or c3 in my house as I will ever come. Has all sliders just like an real b3. WOW.

The best piano and string sounds that a keyboard has to offer. I do both live and studio work and I need the best I can find for both. For live, I love the K2500XS because of the Quick access banks which let you store sounds into an area of the keyboard where you can find and get to them very quick. For studio, all, yes all of the sounds are as close to the real thing as you can get. My clients which I play for love that as much as I do. Aftertouch is very good and better than most boards(not perfect but I don't know of one that is).

I Take it everywhere I go and have never had a problem. In fact, I have never had a problem with any kurzweil product. I never install myself. If your smart you will let kurzweil do that, not yourself or some local who says he knows what he's doing. Follow that rule and it should do just fine.

It's a big keyboard I hate to ship it to anyone but kurzweil is the only one I trust. No way would I let someone else touch the inside of "my baby". No one is as nice over the phone as we would like them to be and when your talking about your keyboard your not eather. But over all they do just fine. Upgrades have always come back the way I wanted it.

I love keyboards and like many different ones but this one is my favorite. I would buy another without thinking twice. I use other alot of other gear on the road like the roland xv88 and xp30, korg trinity and yamaha p-200 but none will take the place of my KURZWEIL.
Big price but it is a big board and money well used.

2.1 Version
The optional sounds are the best of the bunch.
Editing has a steep learning curve, but once learned it is the best!
The Manual is a great effort, but still not very practical.
Overall, it is time consuming to learn, but once learned it is powerful.

64 Polyphony w/ perfect weighted key action. (Just like my old 6' foot grand piano)
Lots a good, editable effects for tracts and final mixes.
It can take on hard drives, more memory, but the manufacturer must install it. Better to purchase with all the goods as opposed to installing later.

The standard sounds a good and some are deeped than others, but the optional sounds are what make this keyboard great.
It works for all styles, especially when you can create your own sounds by over combining and editing several sounds together. There is no end to the sound potential.
It is very reactive to my playing and the sensitivity, velocity and after touch are very dependable and realistic to a real piano.

Never had a problem!

Here is a weak point. Since it is a technical, expensive keyboard, I don't dare mess with it myself. Thus, a nervous trip through shipping to Kurzweil is necessary to have it repaired. Local dealers are useless for service.

I would buy it again! It was worth every dollar to me. I love real acoustic grand pianos and this is the only keyboard that I have played that can rival one.
It affords me more creativity and musical independence than any keyboard out there. The only thing I wish it had was a more user friendly interface. Despite the lengthy time needed to use it proficiently, I am always surprized at what else it can do.
The keyboard has wonderful sounds, endless room to create new interesting sounds, sampes, songs and musical support for performance. The only catches are that you need to purchase one loaded with all the options of memory, sounds etc... and you need lots of time and patients to learn its complex abilities.

2.1 software version
Good presets, but upgrades are better
Editing is easy once learned
Extensive, not user friendly (technical)

Has it all.
Better to purchase with upgrades, rather than install latter.

Excellent, works for all types of music, it is very flexible and creative w/ new sound production.

Works perfect everytime

I would do it again, anytime.
This has been a one time purchase and I do need to purchase another.
This can do all that I need it to do. It's the best!

Software Version 3.50
The Presets ("Programs") sounds good. No real depth in any area (who would expect that anyway?). The stock piano sound is quite tinny sounding, almost irritating. It works great as a pad for other sounds, but I wouldn't use it for solo piano--ever.
The interface is done with click buttons, and getting around isn't too bad but I couldn't say it's easy to use. To enter a text string, it has a telephone like interface and you have to +/- your letters to get the right one. Annoying at best.
They have a neat thing to help ease of live performance, called QuickAccess banks. You can put several program/setups in a group and switch between them quite easily. You can have over 200 of these QA banks.
There were two manuals, and two videos. The videos are excellent and I've found the manuals to be quite comprehensive (althought they are truly only reference manuals). The main manual is about 1" thick.

48 voice polyphony. It's behind the competition in this category. But unless you layer it up thick with stereo samples it's difficult to notice. Kurzweil encourages the following challenge (try it on all keyboards you're interested in): Hit a chord with your left hand, go nuts with appegios in the right hand. You can still hear the left chord after many many appegios. They make the claim that their voice-stealing algorithm is the best.
The keyboard action is good, I would prefer a piano-- but alas that's not in my current budget-- yet.
It is rich with built in effects, all kinds of Filters/LFOs/DSP effects etc. You can funk up a sample any way you can think. People have complained that the built in effects aren't rich enough, but that the KDFX option is amazing. I've had no trouble using any of the effects. One of the neatest features is LIVE mode to process a live signal, through the onboard effects.
It's as expandible as your wallet is thick. You name it, they can add it-- memory, sampling memory, ROMs, effects, Digital Multitrack interface, hard drive, etc. It also has a SCSI 1/2 interface.
The keyboard does send aftertouch. The MIDI capabilities are the most impressive thing about this keyboard. Essentially any controller is mappable to any effect and some effects can be used as controllers (this is what they call V.A.S.T.). You even have 4 mathematical functions that can be applied to controllers. The possibilites are factorial!
It has an on-board sequencer that is easy for me to use than Cakewalk on my computer. Cakewalk is easy to use overall, but it interrupts my train of thought to go from keyboard to computer and back to record sequences. So recording into the internal sequence real-time is easier for me. Then post record touchups in Cakewalk.

The expressiveness of it is amazing. Especially when you get some quality samples loaded into (like the Bolder Piano). The number of controllers make it real convient to change the sound in any number of ways.
I would say this keyboard is quite general purpose and can do just about any music you set it up for.
Onboard effects (pan/reverb/etc) are okay.
It reacts to the playing immediately. The only weirdness is that the sliders value tend to jump (quantization) when you move them rather than a smooth transition. Welcome to digital.
The reaction to velocity is great and totally programmable. Aftertouch I've not used much, but you really have to touch hard to get it kick in at a decent amount.
I'm giving it a 9, because a real instrument instead of a sample is always better.

It seems to need to be rebooted a little too often for comfort. They also seem to be quite sensitive to line noise, so a line conditioner for live shows is almost a must.
I will be gigging without a backup-- because I can't afford one. Now when some sweet record deal lands in my lap, sure I would definately buy a backup.

So far no problems

I would definately buy it again at the price I paid. Of course I bought what they call "Z" stock or refurbished. Somewhere between new & used. It's worth what I paid, no doubt in my mind.
I've been playing on and off for many years. I own a Voce V5, and a Mackie Mixer.
What do I love about it, this is the beauty of the Kurzweil. It can be beat in any single category by another machine (except that mappable VAST architecture), but you can't get this many features in one package. Simply for a road keyboard, it's all you need in one package. No nightmare of wall warts, MIDI cables and rack mount boxes with wiring and re-wiring at each gig. It really simplifies things by having it all in one package. What do I hate about it, the fact that I must reboot it frequently.
Expandable polyphony would be nice.

software: OS4.04 (this is the kdfx OS). the OS is upgraded regularly and can be downloaded off the net onto a floppy and installed into your machine.
presets: presets on this machine are called "programs" and are easy to dial up and play with. the sequencer is super but is a little difficult to use because of the small screen. to be frank, this is not an easy machine to use - but mainly because it can freaking do *everything* :). i bought this thing 7 months ago and i'm still learning it. the manuals are adequate but not awesome. (i couldn't find the ouput impedances anywhere). it comes with 2 videos and there is LOTS of online help from other K users. my only real gripe in the "easy of use" category is the programming interface. you have to type in letters for names etc. on a numerical keypad. it's like trying to type a letter to someone using a touchtone phone :). the obvious solution is to make it interfaceable with a PC so you can type names and program (the sequencer especially) the thing with a real keyboard/mouse (ala Alesis). i suppose almost all synths suffer from this. someone wrote a free computer controller for it but it uses the midi port so it's useless when you want to record/transmit midi. there is an SCSI port that could be used for this, tho. maybe there's software out there i haven't found yet. (MOTU? librarians?)

my machine has: piano, orchestral, and contemporary ROM block expansions; KDFX digital effects; sampling option; PRAM upgrade; and espresso machine attachment (just kidding).
the synthesis engine is digital sample-based. 48 voice polyphony, velocity and aftertouch - 88 keys. it also has controllers up the wazoo: 2 ribbon controllers, a breath controller, sliders, buttons, wheels, 5 pedal jacks - comes with sustain pedal. the action is lighter than a piano and heavier than a cheezy casio. that's all i'm saying :) you have to try it for yourself. it's nice. the controllers and keyboard are *extremely* flexible. you can route the controllers and arbitrary sections of the keyboard to almost everything, including the KDFX effects. this is good if you play live and need to do a lot of stuff at once. (unfortunately, this thing weighs 70lbs...) out of the box, this thing is not GM friendly but it can be, through programming/stealing other ppl's programming off the net :) it can read and save sequences to midi format.
the i/o's are analog, spdif, and aes. digital i/o's are 16 or 20 bit, 44.1 or 48 KHz. there is also an optical digital input. i haven't yet tried to sample anything.
this thing can supposedly read akai, roland, and other sounds but i haven't tried to use any yet. because of the unique synthesis engine, soundware not specifically written for the Kurzweil platform won't be nearly as flexible as that programmed for the K. i'm no (V.A.S.T.) guru, but the basic idea is that a preset or "program" can use many keymaps/samples overlaid and/or interacting with each other according to a huge list of algorithms the programmer can choose from. this thing can even do virtual analog sounds well. there are many K-specific CDs out there.
the KDFX unit is a must. the default effects are incredibly noisy and are converted to analog before they go in. the KDFX option makes effects completely digital. you can even use the KDFX as a stand alone digital signal effects processor for other instruments. it has special leslie and rotary effects to support the KB3 mode which simulates a Hammond B3 with midi sliders acting as drawbars.
i wish it supported word clock or midi time code. it supports midi clock. if you're recording audio instead of midi you can use the spdif, which has timing info embedded.

in the end, the thing you will notice the most are the price tag and the sounds.
since i hate trying to describe how things sound by typing, you're just going to have to take my word for it and check it out :). the KDFX sounds great. Sweetwater Sound has several demos on their website.

it came with an intermittent bad contact on one of the unused CC foot pedal jacks which cause the volume level to drop out sometimes. i opened it up and cleaned/jiggled it, and it was gone. no other problems. i use this in my home studio. i don't gig but i'm sure it would be reliable. only problem: it's heavy.

i've never dealt with Kurzweil except thru their website. the retailer, Sweetwater Sound, was extremely knowledgeable/helpful in explaining the options. they also have a lot of K resources on their site, including many great sounding sample CD's they make specifically for the K.

i'm not giving it a 10 only because this thing costs a *buttload*. it's extremely overpriced. especially seeing as they're made in Korea? with the current exchange rate, they must be making a killing. it's a hell of a machine, but you have to decide whether it's worth the extra money, or whether you should buy an Alesis and a new motorcycle :). i was also considering the E-mu E-synth, the Korg Trinity, and the Alesis QS-8. i'd buy this again but prolly the 76 key version (no X in the model name). i never come close to needing 88 keys. but wait, that keyboard has different action. doh. maybe a K2500RS and midi controller. :)
another thing you should know: in terms of polyphony and the digital I/O there are other machines out there with more. (i.e. more voices and faster sample rates/longer word length). the SCSI port is SCSI-I and can only read CD-roms at 4x. the tradeoff however, is that this machine is STABLE. it's been debugged. it has yet to crash on me. i haven't come anywhere near using all the polyphony anyway, because i record tracks separately into cubase.

Software version 3.5x. I have found the synth architecture difficult to program and completely unituitive. I can only say, 'Thank goodness for some free tutorials on the net.' The manual is practically useless, which is incredible considering the fact that it weighs as much as phone book. The videos are about as boring as boring gets. In terms of editing the sounds, it would have been helpful if frequently used parameters, such as EG and Filter settings, could be mapped to knobs or sliders.
The presets are nice and the overall sound of this unit is what made me purchase it. Somehow it cuts through all of the "synthy" sounding keyboards.

Polyphony is advertised as 48 voices/192 oscillators, but this is actually quite misleading. You will never get 48 voices of polyphony out of this unit under normal circumstances. While the K2500 can emulate many analog sounds quite well, it often takes 2-3 voices of polyphony where a real analog would use only one voice. The reason is that a real analog has two or more oscillators per voice, whereas the K2500 can use only one osc per voice when it has a resonant filter going. Therefore, the K2500 has to use a whole new layer to get a second oscillator. Hold down a a three-note chord with each note using up two voices and there goes 6 notes of polyphony. Also, a stereo sample will use up two voices per note.
The standard built in FX is a Digitech unit basically equivalent to the ancient DSP 256 (but not quite as powerful in terms of MIDI control). It's not bad, but you'll definitely want to get the KDFX as soon as you can. The Digitech unit gets its input as an analog signal from the K2500 synth engine whereas the KDFX gets it digitally. This will have a big impact on the noise factor. Also, the KDFX interfaces back into the synth engine itself. The KDFX offers four channels of insert FX plus 3 Aux send FX. For details check out the Kurzweil web site. As far as I know, this is most powerful built-in FX unit of any synth/sampler.
The expansion capabilities are pretty impressive; check the Kurzweil web site for details. I hope that Kurzweil makes a new chip for this unit that supports more polyphony.
It's got more MIDI capability than you'll ever need.
It has an onboard sequencer, but I don't see this as being much use. Not that the sequencer itself is bad, but it gets its memory from the PRAM section instead of the sample RAM section. PRAM can be a maximum of 1.2 Mb (and I only have the stock 256K) which is shared with loaded programs. You simply run out of memory too easily, especially if you're turning knobs and pitch wheels. When the sequencer runs out of memory, it just stops playing.
One of my complaints about the sequencer is that each track can only send data to one MIDI channel. The old Yamaha QX5 was only an 8-track sequencer, but once you were done with a given musical part, you could merge it to one track regardless of channel. This allows the other tracks to operate as working areas and the 8th track is the main track, which of course could be unmerged by channel. The K2500 sequencer, with only 16 tracks should employ this technique.
The keyboard action is great. Of course, with fully weighted keys, you're looking at 72 lbs plus and Anvil case to lug around. DON'T EVEN THINK ABOUT AN SKB CASE!

As I said, the sonic quaility of this synth is unsurpassed. It has real bottom end without futzing with EQ. Somehow the clarity is so good that you don't have frequencies stepping on each other. It's great at producing a wide number of sounds, from analog to sample playback. However, even though it has a variable architecture synth engine, it's still NOT the same as Virtual Analog. For analog sounds, the Access VIRUS blows this synth/sampler away. Also when programming an analog sound, most of the time you'll be working with a single cycle sample of a square, sine or saw-tooth wave. This creates problems with portamento, pitch-bend and pulse width modulation. To get PWM you'll probably have to sample it from an analog synth.
The unit will work for any style of music, but if you're going to do techno, then you WILL need something analog or VA for flavor. One of the failings of the synth engine is that, even though you can modulate the Attack, Decay and Release time of the envelopes, you must modulate ALL or NONE of them. It's things like this that lead to frustration with programming the K2500. You expect that there will be AT LEAST AS MUCH power as what you've had with other synths, not less. So the interface frustrates you because you're hunting around for these missing pieces.
Another complaint I have is the whole arpregiator issue. The arp can only be used in multi-mode (Setup Mode). Secondly, while it has many latches, it doesn't have one like every other keyboard arpeggiator made in history. Again, you expect this unit to have AT LEAST the power of predecessor keyboards. Lastly, there's no concept of storing arpeggiator patterns and navigating between them.
With respect to expressiveness, the K2500X is unsurpassed with all of the physical controllers which are mappable to and MIDI CC.

This is worst part of the the K2500. I had to return two units. The first one had a huge dent in the chassis, the second one just died after about 12 hours of use, and the third is currently in the shop with an intermittent problem which causes the sound to drop to zero. I then have to power off the machine and power it back up. YOUNG CHANG DEFINITELY NEEDS TO ADDRESS THIS ONE.

Tech support is all right I suppose, but I wouldn't rave about it.

I still think the K2500 is a great piece of gear, but as I've come to know it better and work with it, I see that it has some flaws that I wish weren't there. My other gear includes a Matrix 6, Matrix 6R, Access Virus, Korg Z1 and Roland Super Jupiter (MKS-80). None of my other gear is really like the K2500 so I can't really make an even comparison. I bought it as a workstation synth, and as great as it is, it's not the end-all, be-all. I never thought it would be. Nothing ever is. At some point I believe I'll get a rack mount version for portablility and more polyphony.