- Yamaha's Motif XS has some sounds that were adopted as signature sounds for some subgenres of funk, soul and gospel, but these are just samples that the upgraded versions XF, MX, MOXF have as well for this reason, and I don't see anyone with the XS anymore.
- Nord clearly limits the features, storage and processing power of each keyboard they release so that they can upgrade it slightly the following year (the latest 2018 flagship model has 480MB of sample memory vs. the preceding 2015 model's 380MB).
- Korg rereleased the Kronos with an SSD instead of a HDD and marketed it as a new machine. You could open it up and DIY for 80 bucks and save yourself ~$1.5k+ upgrade costs.
- Roland still slaps the Juno brand name on random iterations of digital instruments that just have an extra button for this or that function that could have been added with a software update if they wanted to.
New digital keyboards these days are just software updates that model familiar sounds slightly better, packaged in "new" hardware. The $3.5k pricetag for flagship keyboards that have barely changed in size/shape/material for years is a clear sign. I wonder why no manufacturer has just come out and said "this is our flagship keyboard until 2030, buy it for $2k and subscribe to software updates for $10/month" or "new software verson at $100 every year". That way what buyer's pay for would be much more closely connected to what they are actually getting.
Some historic digital innovation. It seems to me that almost everything PPG and Waldorf ever made or makes would be considered innovative, including the upcoming Kyra. Other innovative digital synths would include the VS and Wavestation family; the Fizmo, Morpheus, UltraProteus, and Proteus 2000; the FS1R; and perhaps the Prophet X. And I must grudgingly admit that the MicroKorg was innovative given what they crammed in there for the price.
I'll grant you that most of those devices are two decades old. The current incentive for innovation (and hence risk) for digital devices has been destroyed by software synthesizers and laptops. Most digital stuff nowadays has gone for cheap rather than new, in the hopes of going after the poor musician. Monologue, Monotribe, Volca, Reface, Boutique. I don't know if that's bad, but it does make me sad.
Why is this? I've always wondered if these golden-age hardware FM synths provide any benefits over software (people talk about the super HQ DACs, etc., but I'm not sure if I buy that these components are better than modern commodity equipment?). The thing is, to my ear, the SY99/SY77 etc. do sound a lot better than e.g. Dexed or FM8, but is that just because Yamaha patented a bunch of the FM algos and architectures, and, with a retail price of £3,000 in 1991, they put more care into a complete end product than a VST FM developer realistically would? Or, can really low memory, low CPU, super purpose-built hardware somehow win against a modern OS?
As for the sound, I don't think Yamaha's implementation of "FM" [1] has been comprehensively reverse-engineered in the way that, say, the Commodore SID has. There are a lot of little quirks and edge cases to take into account when considering the full operational ranges of the various chips. Even MAME's implementation is allegedly distinguishable even after 20 years of tweaking and testing against hundreds of games, and I imagine most VSTs are using significantly less mature code.
[1] I recall reading that the actual implementation is phase modulation because directly doing FM in the digital domain would put quantization error in the frequency domain, i.e. notes would be off-pitch instead of having noise.
OTOH the things that tend to differentiate implementations of Yamaha's FM are the sample rates, bit depths, and envelopes used, plus any output distortion(YM2612 for example has a well known distortion in its implementation that adds a harsher edge). The core algorithms they use are something a high school student could pick up and do something with, and emulation quality issues are more a matter of it being easy to write an emulation that gets it 98% correct without covering the last steps, since those are details that really need error-for-error reproduction of the original ASICs and boards, including any timing issues - things which frustrate emulator writers everywhere.
Dedicated circuits.
This isn't all in CPU - the CPU on these synths mainly sets parameters for the sound generating chips.
not the same chips, but something like this probably:
The SY99/77 really are great, though. I sold my TG77 and FS1R recently, but will probably get myself a used SY99 keyboard at some point. Or save up for a Montage.
There's a reason why so many keyboard players adore their Nord keyboard, despite it having relatively old-fashioned technology. Nord instruments are incredibly ergonomic and sound absolutely killer, largely because of their obsessive attention to detail and their deep relationships with working musicians. A trivial example is the music stand - it's rock solid, it fits in the gig bag, it slots in place in two seconds and it's wide enough to hold four pages. It's a really important feature for a lot of Nord users, but it just wouldn't occur to most engineers.
Pressed steel, Neutrik jacks and keybeds aren't subject to Moore's Law. High-end stage keyboards will always be expensive, because they're built to high standards in relatively small quantities. The lack of innovation just isn't particularly relevant, because old technology does the job perfectly well.
We're talking about very mature technology. The difference between Nord's 100MB piano sample sets and a 20GB mega-multisample is extremely subtle. The synth and effects engine on the Nord Stage sounds fantastic. You could add a ton of sample memory and processing power, but the sonic benefits would be absolutely marginal.
You can't say that about our computers or mobile phones, except among the hoarding/collectors scene.
It'd be great if the other realms of electronic gadgetry could accomplish the same degree of uptake as electronic musical instruments - however, the anti-patterns that make modern consumer gadgets so appealing to the people who market and sell them, are a smell to musicians who have very little patience for designed obsolescence. Musicians don't tolerate that much .. anyone attempting to induce it in a product intended for music-making will find that they won't get far in this industry.