Comparing Kurzweil K2700 to the K2500

My plan is to replace my old K2500 with the new K2700. They promise that K2700 can load K2500 sound programs. This was one of the key criteria when I purchased the K2700 instead of some other workstation as I really would like to still continue using the sounds I like from the K2500. So in this video I will try out some K2500 sounds on the K2700.
Note that the K2700 comes with a huge sound library, with more advanced and complex programs and having much higher quality samples and algorithms. I'm not reviewing any of those here, only the old K2500 sounds and some short generic sound quality tests.
#kurzweil #k2700 #k2500 #synthesizer #workstation #sampler

[@ChristianMartirano]

When Kurzweil began engineering products again, after Young Chang had sold the company, there was a new group of engineers. They created a new set of algorithms that are not identical to the algorithms used in the original K2000, K2500, and K2600. it is impossible for the K2700 to perfectly read files from the older models as the algorithms themselves are different. Kurzweil has not made a set of compatible algorithms that would allow the programs to translate perfectly. Before the sale of Kurzweil from Young Chang to the current owners, The K2000, K2500, and K2600 could all read the same programs and therefore someone with the K2000 could move forward to a K2500 and a K2600 with certainty that their programs would load and play correctly . That is no longer the case. The K2700 is a very powerful instrument with much greater capabilities than the previous models, however, the user must understand that in many cases, they will have to re-create programs rather than just import them.

[@machinelanguage5108]

I much prefer the sound of the older K-series units to anything Kurzweil has put out post-2600/2661. They have that full, thick sound that you found on many 90s samplers (AKAI S1000/S1100, ROLAND S-770, EMU E4 series, etc.). The newer Kurzweils sound cleaner, more hifi, but much too sterile to my ears. They all have a glossy sheen on everything with a ton of emphasis on the hi-mids & treble. The K-series have much more mid-range presence, and just sound punchier. I like a little bit of grit. Having said that, if Kurzweil releases a smaller version of the K2700 with regular key action, I would love to have one. I just see the new Kurzweils as totally different instruments from a totally different company, based on the old K-series but with a redesigned audio engine and VAST environment. I have had the pleasure and privilege of using all of the K-series units, from the K2000S (V3), a K2500RS which I had the KDFX installed into (boy do I regret selling that- Mint condition - gorgeous-sounding machine), and 2 K2600S units over the years. I love the K2600S, but I was recently given a K2000 fully expanded, and I have to say the K2000 is my favorite sounding unit of them all. The K2600 is much cleaner and simply amazing in every way. The K2000 has always had a dark, melancholy sound to my ears which I love.

[@GrimVoxTech]

Thank you for your insight! This is so true. Sadly they removed some algorithms. I would imagine they could have kept them unless they lost the code and needed to re-create everything from scratch. But the new stuff sound awesome, I'll try to "repair" some patches in my next video and see if it is possible.

[@user-cr2gj8kw4e]

@@GrimVoxTech very much so

[@EmilSaks]

@@machinelanguage5108 couldn't agree more. K2000 is still best sounding machine of them all, at least for me.

[@arrakian]

@@GrimVoxTech I’d think it would be possible to get some of Young & Chang’s ex-employees/engineers to come in and help with getting the 2700 to play the older “K” algorithms.

[@ahojahojish]

I swear these older boards always sound more PHAT and delicious. Its almost as if the newer instruments are too perfect, too clean to their own detriment.

[@pekkamontinmontin4200]

When you open the old kurzweil models, you see lots of things happening inside the machine. Try to open these newer models...dead plastic inside. I quess that tells something too.

[@Shrebina-kq4cs]

correct !

[@GrimVoxTech]

These are digital synthesizers. The frequency response and distortion levels are beyond human hearing to distinguish if the samples and algorithms are the same. There were wrong K2700 samples in many of the patches in this video! After I made this video I made software to help me with the patch conversion. Then I was able to find the correct samples for almost all patches - yes, almost all K2500 samples exist in the K2700! Also, I was able to correct many of the algorithm parameters. Now almost all patches sound identical in K2700 and K2500. This with the exception that the K2500 is noisier due to the effect unit.

[@danthreepwood2760]

I agree 100%, and mostly they actually do. But that's also partially because a fully loaded K2500XS went for more than 15.000 USD in 1996 (about a gazillion current USD with inflation correction) and it weighs about 80 pounds. Also, legend says the sheet metal is so thick that nobody ever managed to get a dent in it, ever.

[@jamessisson3703]

Nice setup. Thanks for posting this. I wondered how they differ

[@tragus44]

Awesome video, I have a Pc3x, K2000. and k2600xs, as these keyboards are aging I have been thinking about getting the K2700. This video was awesome to show the improvements in the noise floor and the improvement in the algorithms. However, It is a shame that there is not an easy way to export older sounds and have them sound the same. I hope you keeping making these videos as your information is invaluable!!!

[@GrimVoxTech]

Thank you for you comment! Yes I'm a bit disappointed that the algorithms have changed and are not compatible. However, most of my own patches are sample based and use only simple low-pass filter algorithm and all my own K2500 patches import without any problems to the K2700 and sound great. My next video will look into the algorithm changes a bit.

[@jackb6602]

I bought the 2500 as Rack in 98, now after I saw your review an comparisions, not sure to do the step..! So much important work you did. Great thanks an greetings from Belgium

[@AlekVila]

Wow, I felt your pain. I had a similar experience when I bought a PC3. It just didn't compare well to my old K2000. It's hard to believe that my 30 year old synth still can't be beat. It's confounding that Kurzweil mever created a proper sequencer for a such a powerful multi timbral instrument. I love that they finally added the drum pads. I would love to design a K3000 for them. Ha... I ended up selling off the PC3 and keeping my K2000.

[@GrimVoxTech]

Yes it was a unpleasant surprise that I could not import the old patches and immediately continue working on the K2700. But quality-wise and feature wise the K2700 is superior. And if you take a look at my latest video I have now finished converting the patches and they are now identical except just a couple. The drum pads are useless. The sequencer works OK for small jobs, for serious stuff I use a computer anyway. But yes, there could be many improvements still and I would also like to work on a project like a K3000.

[@AlekVila]

@@GrimVoxTech That's great that you were able to get the patches to align better! I'm curious. Why are drum pads useless?

[@GrimVoxTech]

@@AlekVila The feel of those silicone buttons are horrible and will not give accurate velocity. They are great for controlling the sequencers though.

[@Abruzzo333]

@@GrimVoxTech Feature wise yes but quality no. Just listen to the sound of an original K2000/2500 or 2600 next to new gen and the sound is not even close. New Kurzweil is cold and thin by comparison. There are videos to demonstrate this. All the features mean little when the actual sound engine/convertors are inferior.

[@GrimVoxTech]

@@Abruzzo333 I have spend tens of hours with headphones listening to K2500 and K2700 side by side when fixing the initially bad patch conversions. Now the patches sound identical except the K2500 has noisy Crystal Semiconductor converters and in case the so called sine generators are used, the sine in K2500 is quite crappy.

[@jamescn3539]

Wow !! What a great and honest video ! Well done. Very good !! I do hope that Kurzweil will do a better work in porting the old sounds correctly to the 2700.

[@FugaziSB]

Interesting video, thanks for sharing this important info. Regarding the sound quality comparison, as you said yourself, electric parts do get old, mainly capacitors, so it makes sense that the output quality gets worse over time.

[@hanswurst2490]

Although I have a Yamaha... which is crappy from a to z... this is the first review in 3 years, that really is worth to be called a "review". My deepest respect! 👍

[@angelovdweerden6585]

Great video! (I loooove the K2000, K2500 and K2600 ❤🎹)

[@samplidium]

Thank you very much for this demo, it answers to my questions. Now i know that the K series has ended, sorry.

[@tenderlyone]

My studio is a collection of Kurzweil keyboards (since I am, I am Kurzweil fan). The problem is that, because I’d like so many sounds from the minis keywords I’ve gotten, I haven’t been able to get rid of them, because, invariably, I get to use them in many of my productions. I still haven’t decided whether to get the K 2700 because, in my opinion, they have an improved match, save for the sample play back in a little bit of the sampling capabilities.

[@jo_9805]

Thanks for your suggestions. I have the same problem. I hope for a system update very soon. I have a question for you: the general gain is very very low, especially compared to the old series. Is there an option to increase the overall volume?

[@machinelanguage5108]

Keep that K2500. They sound better, especially sample playback. I love the input stage + preamps on the old Kurzweil K-Series sampling units. The gain on the input is lovely. I also recommend keeping that AKAI S950. Those machines sound lovely and nothing new can emulate them. I love the preamps and gain control on the S950 as well. There is a reason they sell for so much these days. As cool as the K2700 is with 32 layers of VAST + FM + the virtual analog waveforms + massive sample memory, I think they are totally different machines compared to the original K-series. You will greatly miss the K2500 eventually if you sell it, and good luck having a replacement shipped without getting damaged. As far as the noise on the K2500 goes, youv simply need to recap the PSU (power supply) on the K2500, guaranteed. You will hear a night and day difference.

[@GrimVoxTech]

When I bought the K2500 I chose the K2500S with sampling option because transferring samples from my computer would be extra work and slow things down. I was a bit disappointed when I got it and found that the AD-conversion was quite noisy. I was suspecting there was an issue with my unit and went to the shop to test another unit (rackmount version) but it also had the noise. When playing, the system noise from K2500 is coming from the many DA-AD-DA conversion due to the fact that the effects unit has analog connections and their design does not give full dynamic range. Turning down the effects will reduce the noise. It has had noise since new, so no cap replacement will fix that. Humm could possibly be reduced by capacitor replacement, but it can not be heard, only seen on spectrum analyzer, so no big deal. I did check the caps a few years ago and the ripple was not that bad yet. The K2700 can not sample, which is a shame and silly as it has analog inputs with AD converters. Maybe a future firmware update will get us this feature, maybe not. I does play samples very transparently and has a lot more memory - and flash so they are immediately available. This I'm very happy about. But so far I have not found an easy and fast way to transfer samples from my computer to the K2700. Only way I know about is using an USB thumb-drive. That is a hassle as it needs to be inserted in the back of the unit. I would have wished the USB port could have been used to transfer samples. Even MIDI sample dump standard would be more convenient for short samples even if it is slow. The PC application for sound editing and management by sond tower is also quite wierd and buggy. It does not seem to allow transferring of samples either, only patches, but not Kurzweil patch files but their own proprietary format.

[@redeemer665]

@@GrimVoxTech Have you tried the Awave Studio yet from FMJ software? I've been working with them to get a proper support for Kurzweil formats up to PC3 series and it would be definitely nice to get K2700 support in as well, if you've got any spare time to help with beta testing. Awave doesn't support manually renumbering objects but I hope that can be changed in the future.

[@GrimVoxTech]

@@redeemer665 No, I have not heard about that software. Too bad there is no Linux or WIn XP version. I have actually made already a PC program that reads the .K27 files and lists their contents. The soundtower K2700 editor is not very useful because it has bugs and can not read/write .K27 files. Most of all I would need a way to handle samples to/from a PC. Using an USB stick to try to transfer samples and trying to plug and unplug it blindly in the back of the Kurz is a pain.

[@WARDISWARD]

03:16 It's not a sine wave on the K2500 , it's a parabolic wave that's why it has the overtones an it also uses less computations

[@dirkkeersmaekers4343]

I was hoping for a 76 semi key version,but I don't think it will come.

[@yashnu]

Very nice idea to compare Sines and viewing THD figures and spikes. You can also investigate how a pure Sine sample on the Kurzweil displays on your analyser. A second test would be to use the highest pitched Sine sample from a Keymap, play the lower keys and check THD. The interpolation in Kurzweil is stellar. These should show better figures and lower spikes or less spikes or both. Of course, empty the DSP blocks.

[@trixon45]

Great video! Interesting to find out that the samples dont sound the same, or is replaced? The samples may be numbered differently so K2700 replace them but they have the same number? Have you tried to search by sampla name on both?

[@GrimVoxTech]

Yes, I found out that there are no samples stored in the factory sounds .k25 files you can download from Kurzweil. The factory patches use samples that are in the K2500 ROM. Makes sense, I should have known. And the K2700 have a complete different set of samples onboard, so they K2500 patches using samples will sound different. Only way is to play back each sample from K2500 ROM and record them and create new samples of them and store into K2700. Kurzweil has recently provided a freely downloadable set of K2600 pathes for the K2700. I hope they will re-create the K2500 factory patches too and put them available as a download.

[@markhofland1898]

Nice video, about comparing the K2500 and the K2700. I own a K2500 XS for many years, and still love it. You're right about the noise floor and the 'not perfect' sine wave. But it's just the imperfectness in any matter of many synths who are responsible for creating that sound of that particular synth. Can I create a Jupiter 8 sound on a Roland Jupiter-80? Nope, okay, Jupiter 8 is completely analog and a Jupiter-80 is not. But sometimes, you'll need that imperfect noise floor and imperfect sample or algorithm based sound, to get the right sound.

[@GrimVoxTech]

True. The imperfect old instruments have their own unique imperfect sound that can be very good. In theory the K2700, if being too clean, can always add noise and distortion to get that gritty sound. So you have more options to chose from. Then you can argue, is the noise and distortion similar enough to the original.

[@markusgalla]

I am a professional reviewer and I really looked forward to the K2700 review. I was so disappointed about the quality and the fact that there‘s nothing new but something less. When I read the manual I had a dejavu effect and so I compared it to the Forte and other older instruments‘ manuals. It‘s basically just copy and paste. But: Very basic compatibility to the older instruments. No modern touch display and so on.

[@GrimVoxTech]

Beware that my videos are not a review. There are plenty of those and they show that the K2700 quality is really high. Many have commented to these reviews and comparisons that the K2700 is better than many competing boards. In my videos I'm just exploring some corner cases and compatibility to historical relics. The new K2700 sounds are superb and modern.

[@chezzmusic]

@@GrimVoxTech My first experience with the K2700 is, thats a great and wonderful Instrument. But I cannot compare it with the older Versions. What I like is not only the great sound, there are many modern workstations that produce great sounds, no for me it was the bright possibilities to express the sounds. Maybe other Instruments can this also very well. If you play strings with hard attack they are short and spicatto if you play soft they are legato. Some Brass sounds are similar. I think this is much more important than the sounds. Sounds I can load to RAM. Sounds say nothing about these Instruments. The possibilities to create something new are imortant. And here the K2700 gives you nice possiblities. I was just sitting in front of it for a few minutes and created with my old DX 7 Sound new stuff that really impressed me.

[@chezzmusic]

Hi Grimm Vox Maybe you can help me, course my K2700 is brand new and the editor plugInSE is making trouble. It does not really works quiet good. Produces some mistakes, but one thing is really strange. It filters out Sustain Panel Data. If I connect the Kurzweil in Cubase via MIDI Track directly. IN OUT on the Track, Sustain works fine. If I send it thrue the Editor to Controll the Kurzweil the Sustain Pedal does not react anymore. Do you have a solution for that?

[@GrimVoxTech]

I have no experience with plugins or Cubase, so I can't give advice on that. Maybe the plugin has a bug?

[@torbenanschau6641]

Very interesting video. I'm not sure if you had to do it somewhat differently. Because the .k25 files from the web won't include the ROM-Samples as they typically would be in the ROM already. So the sounds probably are pointing to the 2700 ROM and they might differ. You'd probably had to do it like if you'd want to save .k25 with custom samples. There are ways of doing that in the Kurzweil. Question is whether you are actually able to save these ROM-Samples along as if they were RAM (Don't forget the Kurzweils actually are samplers). The 2700 should be able to then load the correct samples. There will still be differences regarding the DSP sections and how the filters may sound, but that's certainly tweakable. And since there are not many comparisons out yet if any, would you be so kind and one day compare the Orchestral sounds of the two? Because the strings, flutes etc. of the 1996 K2500 for sure beat the standard sounds of that kind of my Kronos from 201x by far. I'd like to see the 27 in that area.

[@GrimVoxTech]

Yes, I talked about the missing ROM samples in my next video. I dont't have the orchestral ROMs for my K2500, but I could compare the orchestral patches that are in the standard setup.

[@torbenanschau6641]

@@GrimVoxTech Yeah I saw that in the next video after I wrote the comment. However I still think there is a way to automatically save your patches with the actual keymaps. Maybe if you go over setups or songs. I recall there were options for this to share songs, samples and stuff.Like if you load sounds with Ram-Sample-Keymaps, they would load into the RAM. Maybe there is a way to save the whole ROM-Keymaps and put them into the 2700. For the orchestral sounds - ok that ROM makes quite a difference and I was indeed rather thinking of those. These somehow still shine today so it's interesting to see what the 27000 brings to the table here.

[@paulwyleciol3459]

00:55 My 2500s complete package with A&B-Rom has 88 fully weighted. Thanks, I didn´t remember the version of the K2500 with the semiweighted. First, when hearing you, I thought: "ok let´s throw the K2500s away", but in the end, I will keept it ;-). Your experience rembered me on a desaster I had with my Kawai K4 - all compositions for my first double CD where "gone", after doing a Midi-dump - complete soundbank-change to and from the Atari ST - that was about 1992 🙂. I thought I can go back to the original-sounds later anyway. But my origial sounds actually WERE NOT the original sounds, wich I dodn´t know! I never got it back. All compositions sounded completely weird with the wrong sounds. That still hurts, as the Atari is still there, but I cannot adress the harddrive with the marvellous 20 MB ;-)

[@wwielenga]

It is probably asked already but is it possible to transfer programs/multi's from the PC3 to the new K2700 and wil these behave as normal?

[@GrimVoxTech]

I don't have a PC3, so I don't know. Kurzweil might promise compatibility but as can be seen here, you need to manually fix the patched after importing. This is mentioned in the user guide too. They have done a bad job implementing the conversion. But it all comes down to cost. They obviously can not afford to implement everything properly. You could buy about five K2700 for the price what one K2500 did cost back in the days.

[@user-cr2gj8kw4e]

I d prefer K2600.

[@-Deena.]

Looks like you will have to keep them both 😉

[@GrimVoxTech]

I will!

[@djgalawak]

cool good musicman, lets new sound design ;) you know roland jv ? what's your rack above patch, mixer ? best vibes

[@GrimVoxTech]

Thanks! My Roland Integra-7 can play the JV patches, but I can't say I know JV sounds very well. Yes that is a mixer based on 3-way switches. I designed and built it myself some 20 years ago. Fully balanced to get rid of ground loops and humm in my studio. Each stereo input can be routed to any of three outputs. Each input is either OFF, LOW, or HIGH.

[@djgalawak]

nice, k3, jv, jd, or modern modal, solaris .. 🙂 bie

[@Hugues1961]

You can try to load the files WITHOUT dependent objects...

[@polishviking3586]

What is the difference between the K2000, K2000VP, K2500, and K2600? Which is overally the best of the four?

[@GrimVoxTech]

I don't have personal experience of the other models but I assume newer models have more features and improvements. Thus, K2600 would be the best.

[@OlegAryutkin]

Imagine loading presets from Korg Trinity into the newest Korg whatever. Impossible. Loading some presets from 30 years ago is super impressive!

[@mrdavies7894]

True, but Korg never promised forward- or backward-compatibility, whereas Kurzweil have. I was pleasantly surprised to see how good most of the DX7 patches loaded up (in the other video) and very _unpleasantly_ surprised by how poorly the K2700 managed the K2500 files. Ironic and sad.

[@OlegAryutkin]

@@mrdavies7894 thats definitely unexpectedly bad. This is why I gave up on hardware synths - you upgrade to new generation and gotta do many hours of sound design and programming live sets again. Switched PC and now Mainstage. I still have my full legacy sound set and live sets every time I upgrade a keyboard or get more powerful computer to have latest piano sounds.

[@hschieck]

I can well understand your disappointment. Would it have been so difficult to integrate the old or compatible algorithms? New features are great, of course, but one of the strengths of Kurzweil keyboards was that you could continue to use your old sounds over the generations of instruments. Why did they need to stop supporting that?

[@jeffevansmusic]

I have owned many K2000's keyboards and racks. I have also owned the PC3K6 as well. They are not alike in sound at all. Currently I have a K2500R and love it. They do not sound the same. By far the nicest sounding Kurzweil is the K2500/K2600. They changed everything with the PC3K series and also this new K2700 is also nothing like the K series either in tonality. (By the way I get no hum or noise from my K2500R either. They probably fixed that in the rack version) Please keep your K2500. You will regret it if you sell it. If you fired up a warm string patch say on both the K2500 and the K2700, the K2500 would eat it alive for its sound. They are built better as well. My PC3K6 started paying up too. First the display and then the power supply. Quality of construction inside is way better with the earlier series. (I am en electronics engineer and have worked on the K series and the PC series and the PC3 is poorly made. My PC3K6 was also supposed to load up K series sounds but like you here it sort of did with some sounds and was way off with others. The only way you are going to retain the K2500 sound is to keep the K2500. The K2700 is no replacement in anyway for the original K series. It's a different instrument. Another thing, people are releasing new sounds for the K series. The new sounds are incredible. (LFO Store, KPower etc) These patches are beyond belief. So deep and complex, its ridiculous. People are pushing the boundaries of K series right now. Also my K2500 reads Roland and AKAI libraries. I have got a CD ROM drive attached with close to 1000 CD ROMS now! Not many synths like this can read not only their own libraries but two others!!! Roland and AKAI sounds also sound way better than Roland and AKAI samplers as well on a Kurzweil K2500.

[@GrimVoxTech]

Thanks for you comment! Yes, I'm a bit disappointed that Kurzweil changed the VAST by removing some algorithms. They should just have added new features without removing any of the old. This would have kept compatibility. I plan to make a next video looking into these algorithm changes. The K2500 is noisy partly because the signal is being converter to analog and digital back and forth as the effects unit is a separate unit with analog connections. They use Crystal Semiconductor AD/DA converters, which can be good but require a very strict design to keep noise out. The noise is not that bad but can be heard if you crank up the volume. The K2700 is perfect in this sense - superb audio quality. The hum seen in the spectrum is really not possible to hear, and might come from my cabling. The K2500 was temporarily connected for this test and did not have optimal cabling.

[@jeffevansmusic]

@@GrimVoxTech I enjoyed your video for sure and thanks. I am convinced that everything that came after the K2600 is just a different thing. My PC3K6 sounded excellent for sure. Pristine and clean but not the same as the original K series. (Bottom end in the K series is just super fat and deep!!) They went off in a different direction with the new models. They are trying to make out its a continuation but in fact it is not. Please look into these new sounds for your K series from both LFO Store (AlchemyK2) and KPower. LFO Store has released three new K2000 banks now. They are fully compatible with K2500 of course. You wont believe what you are hearing. People have programmed these sounds so well, it has taken this synth right out into the stratosphere. My K2500R rack is still pretty quiet by the way. Even with my monitors turned fully up its only barely audible so it still has a pretty high S/N ratio. My LCD display started acting up as well. I have got a fancy new LED display which is way better and will last forever. No backlight required. if your display dies in your K2500 do not despair.

[@scottsullivan234]

I prefer appliances (hw synths) to PCs (software synths). The lag in using Windows or Mac OSX is annoying. The operating system and the hw are just too laggy. I found the noise (hiss) on older sound equipment annoying also. Going all digital cleaned a lot of that. So I do like the new synths. But I see the Kurzweil OS is still very buggy. Perhaps Kurzweil should adopt a very minimal version of FreeBSD on ARM processors.

[@yashnu]

The OS isn't buggy at all.

[@scottsullivan234]

Ignorance must be blues.@@yashnu

[@yashnu]

Ah you meant the Computer, not the synth. Yes, these are very complex software. Bugs are a fact of life there.

[@spareroomstudio]

I was considering purchasing the k2700. I own the 2600 and this video was very depressing on the importing of patches from the older units. Kurzweil should not have changed their technologies, or they should have found a way to make sure the 2700 would be compatible fully with older units sounds. I think at this point a new KZ is out of the question until they can address some of the issues brought up by many users. The 2500 and 2600 were so much better. I would have expected the next gen to be greatly improved. Oh well.

[@GrimVoxTech]

If you check my later videos you'll see that I was able to convert the patches to sound almost 100% the same. There is no problem with quality of the K2700. The problem is only that they did not spend too much money to develop compatibility so that the patches would be automatically converted correctly. Their attempt results in wrong samples/keymaps being used and parameters are not converter correctly either. One could make a 3rd party conversion software to do a conversion perfectly. I have actually already reverse engineered partly the K27 file format and made a patch utility program. There are thousands of new patches for the K2700 that sound awesome and much better than K2500 could do. The ability to play K2500 patches is a niche for people like me that have incomplete projects hanging around for years and no space in the studio for two Kurzs.

[@Abruzzo333]

The K2500 sounds FAR warmer and more organic than the 2700. Don't know where they went wrong with their new audio engine but it's night and day by comparison. background noise means very little....in fact it probably adds to the harmonics in a positive way.

[@GrimVoxTech]

Warmer and organic? These are not animals. What patches do you use to do this comparison? In this video of mine the patch conversion is totally screwed up; parameters are wrong and completely different(!) samples are used. In my later video I have fixed the problems. There the patches sound identical between K2500 and K2700, except the K2500 is less HiFi. If you like LoFi sound you can always add noise and distortion in the K2700 patches or put it through a fuzzbox. But in K2500 you can not get a cleaner sound that it gives you - so it is limited.

[@Abruzzo333]

​@@GrimVoxTech I'm talking about the actual converters of each synth. It's not about adding distortion. By organic I mean warm and alive sounding....as opposed to sterile and computer-y. The video below is a great example of the sound differences between old and new generation Kurzweil instuments. The difference to me is night and day. The newer Kurz sounds like a VST in a keyboard....where as the K2661 sounds alive. kzbin.info/www/bejne/pKubnKmoec-Eac0

[@GrimVoxTech]

@@Abruzzo333 The DA converters? There is virtually no distortion in those as both have sigma-delta converters. The K2500 has crystal semi converters, which are often noisy if the board is not carefully designed. The K2700 converters are transparent and have no impact on the sound. These are digital synths! They are not alive or warm. A sound is said to be warm if it has even harmonics. The sinewave generator is improved in K2700 so it is truly sinewave. The K2500 has all kinds of harmonics in the sine gen - not warm! Filters and most other VAST algorithms are identical between K2500 and K2700 if you adjust the parameters correctly! The parameters have changed but they can be tweaked so they sound identical. That video seems to compare different patches and blames the engine for the differences. Quite a religious, or actually superstitious opinion that is totally incorrect.

[@Abruzzo333]

@@GrimVoxTech Just listen to the side by side comparison in the video I sent you or search "kurzweil k2661 vs pc4". It's the first video that pops up by Sanctuary Phiosophy and Music. The sound between old and new gen Kurzweil is NIGHT and DAY!....Not superstition at all. You do know that different synths/keyboards use different digital to analog convertors to convert audio to what you hear don't you? They are vary greatly from one instrument to another. Some are good, some are cheap sterile and cold sounding. The sterile sound quality of all Kurzweil instruments after the K2600 has been discussed by many at length within online forums such as gearspace.... So yes WARM...ORGANIC. early Kurzweil K series are known for this. Doesn't matter that it's digital, they sound analog and not like other digital synths like DX7's, M1's etc..If you can't hear a difference between the two then you're not very discerning. Companies change, they cut corners. Some companies that once had a great name are not the same.

[@RoyMaya]

This is why it's just better to keep old gear around. It's too much of a hassle to try converting sounds and the sound will not be exactly the same. My K2500rs isn't going anywhere anytime soon.

[@GrimVoxTech]

Yes it is unfortunate that I have some many unfinished projects that need the K2500 patches. Otherwise the K2700 has plenty to chose from for new projects. But if you check my later video I have now fixed the patches and now they sound identical between K2500 and K2700, except K2500 is slightly noisier.

[@josejusto7519]

Definitivamente, os sons do k2500 são bem melhores.

[@Donetur]

I had a k2661 several years ago, and when I imported k2500 patches to the k2661, it sounded like crap, not even closer to the quality of the videos/demos I saw in the internet, so this doesn’t seem to be a new thing.

[@GrimVoxTech]

OK. I guess Kurzweil is one of the few allowing importing sounds of old models. However, as the user manual warns, import function is not perfect but you need to manually tweak the sounds. Due to this some people start to think the new models have less quality overall. However, only the import functionality is of low quality. Kurzweil should have made more effort to deliver the promise of compatibility with old models.

[@metanoja9804]

Numbers of samples have been changed in waveform collection but I suppose all other parameters retained the same values. Why don't you try to simply exchange the samples in programs. It is quite some work but may be worth for some of your favourite sounds. Workstations will never be fully compatible because of technological progress and market demands. If I liked a program in my old Korg 01/W I needed to convert it manually to my Trinity and later to Triton and Kronos. Still, they don't sound the same because of different filters, output and so on. That is why I still keep my Trinity because it was the last Korg to have quality filters. Sad but true.

[@msld_sound]

Incredibly disappointing. More work should have been done to approximate the old algorithms. I have seen PCM dumps pulled from the K2000 factory, orchestral, and contemporary ROMs floating around on the Internet, so Kurzweil surely could have recreated the K2000/K2500 keymaps with the original samples. What a shame.

[@GrimVoxTech]

Well, most of the algorithms are there and sound identical. As the algorithms have gotten better and more versatile the parameters are different. Disappointing is that the K25 import does not do a better job of automatically tweaking parameters and matching keymaps to the new K27 ones. There still are many of the K25 original samples inside the K27, you just have to find them. The spreadsheet found on Kurzweil website helps. Some samples are now better and sound a little different. I'm currently doing the hard work of tweaking many of the K25 programs for the K27. Most will sound identical, some similar, and some I improve a little. Some are very easy to convert, some take a lot of time. I think I'll post a new comparison video when I'm done.

[@redeemer665]

Yeah, it's a shame they never bothered to include all of the old samples. Most of them are in though. But back to those missing samples, I did the dirty work myself with a hex editor and compiled all the needed data from those dumps you mentioned. The old piano and string ensemble sounds are just a necessity for me

[@GrimVoxTech]

@@redeemer665 Cool! I said wrong in one of my videos. I did find the Chirp sample & keymap in the K2700. Now I'm missing the Trombone. There are many trombone samples in K2700 but they are different from the K2500 one. The "Ensemble Strings" does sound identical to me.

[@redeemer665]

@@GrimVoxTech So you found the Chirp, that's good! About the trombone, I'm looking at the K27 update file right now and there's a keymap #316 Trombone/Trumpet that looks familiar. If the keymap doesn't work for you try the sample #609, sub-samples 9-17 are definitely the K2500 one 😎

[@GrimVoxTech]

@@redeemer665 Oh yes, the keymap 315 Trombone is identical after all to the K2500 Trombone. I had messed up the AMPENV and the shaper so it sounded different. Now I fixed yet another patch to sound identical. This is work in progress - for a long time.

[@sharingeconomies]

LOL

[@DaraM73]

I’ll never buy another Kurzweil after a dismal owner experience of a PC3k88. A Frankenstein machine atrociously built.

[@Shrebina-kq4cs]

Pointless measurements which the human ear doesn't care about. Better measurement doesn't mean more musical sound. Slight distortion can actually sound more pleasing to the human ear, and that's why many old analog synths cannot be beat. This phenomenon is called the "pleasing wave of distortion".

[@GrimVoxTech]

Measurement are the engineering method to explain things. The human ear can be fooled in so many ways. The human hearing is very limited and imagination/superstition can affect the judgement. As people listen to KZbin with various devices, the measurement helps explaining subtle differences that would otherwise drown in the sound reproduction system. A device with low noise and distortion is more capable because you can always add noise and distortion to your liking, but never remove it.

[@stefanbasslorraine8061]

Sorry but I do not understand your video at all ! Distorsion, harmonics and noise are PART of the great warm sound of the S950 and K2500.. contrary to the cold and dead sound of modern things !!

[@quantumeseboy]

Kurzweil is a ruined brand.

[@chrissneider7550]

Kurzweil it sucks...that's why sounds are not compatible...

[@GrimVoxTech]

Why is that? It is quite rare that other manufacturers even try to have any kind of compatibility between their product models. Now I have finished conversion of all K2500 patches and almost all sound identical. Only one of the almost 200 patches sound a little bit different. But yes, it was a totally unexpected workload doing the conversion. Fortunately I did not have to do them from scratch but the import function did help. But it could be better or even do a perfect conversion.