My keyboard setup is quite basic: I have a few MIDI controllers/keyboards, a few sound modules, and a modest audio setup.
Let's begin with the controllers:
The MIDI outputs of the controllers run through an M-Audio MIDISport 2x2 USB interface which allows me to sequence or route the MIDI directly to the sound modules. These days I am running Apple's Logic Studio on a early 2014 MacBook Pro.
For sound modules, I've stuck with Kurzweil and Roland. Kurzweil gives you some really sweet piano samples and Roland gives you everything else. My Kurzweil modules include the newer PC2R which is an improvement over my mid-90's era Kurzweil MicroPiano. But, since I upgraded to the Kawai MP11SE in 2019, I hardly ever route the MIDI through the any of my sound modules unless I'm looking for a unique sample.
For my Roland module, I have a JV-1080 (64
note polyphony, multitimbral; upgraded from my original JV-880) with the
JV80-06 SuperSound Set, the JV80-09 Session, and the JV80-07 Keyboard of
the 60's and 70's expansion boards.
Since the venerable JV-1080, Roland has come out with the JV-2080,
XV-3080, and XV-5080 modules; the latter two offer more voice polyphony
and richer samples. But I'm still tickled silly over my 1080 and they
can be had quite cheap used. Nowadays everything can be done on the
computer with software based samples. I like my older system, though,
and it's great for live stuff without the computer.
The other essential component of a synth studio is the audio. Traditionally, one has a bunch of analog audio outputs from your sound modules that need to be "mixed" and sent to a amplification system so you can actually hear what you are playing. Of course these days one can stay all digital, but I haven't gone there yet.
The StudioMaster 8 channel mixer has large-throw gain sliders and 3 band EQ per channel with 2 effects sends (pre and post). I like it alot since it's pretty basic and large, simple, and clean. All the audio components (sound modules to mixer, mixer to amplifier, etc.) are connected with 1/4" XLR cables which are all of the heavy-duty Excelline variety and some recently added Monster StudioLinks.
The two audio outputs of the mixer run to a Samson Servo 150 Amp and Tannoy PBM-6.5II speakers connected with 12-guage insulated speaker cables. Unbalanced left-right outputs go to a Focusrite Scarlett 4x4 (3rd gen) USB audio interface with A/D resolution 24-bit/192kHz.
The effects send on the mixer goes into an ART Tube MP, which I use as a microphone pre-amp for vocals or my Matador Bongos or other percussion sound makers. For mics, I have a Shure SM57 and SM58 and an AKG Perception 220. I use an Alesis Nanoverb effects processor and an Alesis 3630 Compressor/Limiter to compress vocals, percussion, and when my wife plays her electric bass (which is almost never). All my gear sits on a circa early 2000s custom-made Omnirax SynthRax 88; a 3-tier furniture cabinet with 3 sliding shelves and 30 rack spaces below and sports a Mahogany finish. I have a smattering of other music makers, including a Yamaha FG-411 acoustic guitar, which I always say I will learn how to play but never do!