Korg NTS-1 Nu:Tekt synth kit – full review

Korg NTS-1 Nu:Tekt – £99 – find offers on Amazon UK

Verdict: simple, inexpensive synth kit is more versatile than you expect – especially if you like programming

Recently, Korg seem to have rediscovered their ‘cool-synth’ mojo, From the Minilogue, to the Volca series, and even the high-end polysynth prologue, Korg has shown innovation without losing the consumer-friendly touch. Yes, they have repackaged some old ideas like everyone else, but even then, the thinking behind the tech has been a bit… different.

Korg has progressed from vintage-style USB controllers with plugins, to self-assembly classics, to pocketable, almost pocket-money noisemakers. The range is astonishingly diverse, and nearly all of it is useful for making music – rather than just existing to satisfy the seemingly relentless lust for audio gadgets that exists in some musicians.

And now, Korg has introduced the Nu:Tekt brand. So far it’s appeared on DIY kits of an overdrive pedal and a mic preamp, both featuring an innovative 21st-century valve (also present in the Volca Nubass and Vox amps), and a synthesizer in the style of – but very removed from – the fun Monotron line, the NTS-1.

In 2022 the NTS-2 digital oscilloscope joined the range.

Leveraging the programmable oscillator model of the prologue, the NTS-1 is an affordable DSP-based synth kit that stands out for its open-source approach to the code, which extends to openly shared hardware modifications and 3D design assets.

In short, the NTS-1 is a kit that feels like an enthusiast Kickstarter project, but it comes from a big, established firm that blends strong backing with the hobbyist flexibility that you expect from DIY synths.

If you’ve only seen video reviews, or an NTS-1 in a shop behind a glass case, you won’t grasp just how different it is to gadgets like the CRAFTsynth or Pocket Operators.

Batteries not included. Tools are, though…

There’s not a lot of surprise and delight in the way the NTS-1 is packaged. It falls somewhere between unbranded office furniture and an IKEA kitchen utensil in its white-box flatness, no gatefold compartments and glossy finishes or hand-wringingly ethical recycled cardboard wrappers to be seen…

• Skip the assembly and go to the NTS-1 synth review
• What’s the logue SDK/NTS digital kit about, then?
• Should you buy the Korg Nu:Tekt NTS-1?

This no-nonsense approach is really appropriate for the NTS-1. Inside the box you get the instructions as a big fold-out sheet, like an old-school model kit (there is, inevitably, a video assembly tutorial available too), some neat slots to hold the metal components (yes, actual metal) and the boards in their pink ESD bags. Finally there’s a little bag containing an assortment of screws, stick-on rubber feet and a tiny screwdriver.

Yes, a screwdriver. This kit really does need assembling, not just clipping together. It’s lovely, and reminds me of the high-end Testors/Franklin Mint type diecast model cars you could buy a few years ago.

Assembly is very straightforward, and takes just a few steps. The screw holes are machined, so easy to assemble with no force needed need to cut the threads, which also means you can dismantle a part if you got it wrong.

You won’t though. Perhaps the most nerve-wracking moment is splitting the single PCB into four components; the top plate, base plate and sides.

It’s also necessary to remove the corners from the main system PCB, which you should save as spacers in case you want to customise the NTS-1’s case. The screws are usefully long enough to secure the corners through an extra layer, if needed.

One fiddly moment is needed to release the ribbon cable’s zero-insertion force socket – move the black part backwards then guide the cable in, and lock it in place before sticking the ribbon to the front panel. Everything else is simple, with just two connectors to line up.

Step by step assembly of the NTS-1 looks like this:

1. Remove the parts, sort the long silver screws (for the side panels) and the shorter black screws (for the top and bottom of the case)
2. Carefully break the base and side pieces away from the top PCB/display board (it’s got the controllers and LED on)
3. Attach the four rubber feet to the base plate, and assemble the metal ends and corner pieces with four of the silver, long screws per end. Watch out for the protective film!
4. Attach the end pieces to the baseplate with four of the black screws
5. Take the top plate, and release the black plastic part of the brown ZIF connector by sliding it away from the soldered end carefully. Make sure both sides are released fully
6. Feed the ribbon cable in through the top plate, and plug it in. It should not need force – lie it on the black part of the connector and slide
7. Lock the connector by pushing the lock back to the original position closing the gap at the sides
8. Remove the backing from the ribbon cable’s sticky part, line it up and stick it to the front panel
9. Attach the two halves of the PCB, lining up the pins at each side
10. Lower the PCB onto the base, and secure with four black screws
11. Take the back and front panels, which also prevent the main board from sliding off the pins in step 9 by lining up with the connectors, and fit them with two silver screws at each end
12. And you’re done! Download the librarian and updater if you have time, but you can now connect a USB power source and start playing…

Extras you might want:

• A USB power bank. The NTS-1 doesn’t drain much power from a phone or laptop, but a power bank will let you play on the move
• A simple USB data+power switch. Some settings, like routing the audio in, require the NTS-1 to be switched off and powered up while holding a button. This makes it a lot easier
• Some stickers or tape. The metal contacts on the top do have a coating to prevent short circuits, but that may wear off. Stickers add a layer of protection (and personalise your kit)
• Some thick card, scissors and the 2D template files to make your own front panel cover…
• Headphones. It’s quite loud and obnoxious without!

NTS-1: What does it sound like?

• Five waveform types are provided, but no preset storage
• Mod, Delay and Reverb effects – available to external audio too
• Loud, clear internal speaker

Once completed, the Korg NTS-1 is suprisingly solid and well-finished – you could possibly delicately sand the PCB edges where they’re snapped off if you want a really high-quality feel, but it’s reasonably weighty and lines up well without additional finessing.

Appropriately, the sound is also impressive. In as much as the terms fit, the basic sound of the NTS-1 has character and flexibility; not all square-wave synths are alike for example, and this can do nice, complex phased organs or TB-303 style squelchy bass tones surprisingly well.

It fits into a studio nicely, too – for the most part. There are four 3.5mm jack sockets on the back, plus a micro-USB port, all neatly labeled. There’s a volume wheel here, too. On the opposite edge (front?) there’s a single headphone port, which means plugging into a mixer needs a bit of faffing with levels. This is the only downside, really.

The output is stereo, with good reason; there are three effect slots that support stereo delay, flanger/phaser type mod effects and reverb – but with the advantage that like the oscillator, they’re user-programmable.

Korg’s approach to making a monophonic DSP DIY synth doesn’t appear to be particularly different to other similarly-priced products on the market in terms of processor. The open-source design means there’s a lot of third-party development behind the software, and as you can see, there’s a lot more packed onto the NTS-1’s board than just an ARM processor and a DAC.

It helps a lot, in terms of quality and the time you’re prepared to invest learning how to get the best out of it, that it doesn’t feel like a disposable or unfinished product once assembled.

Because the NTS-1 is a subset of the ‘logue family of synthesizers, it can use the oscillators and effects from higher-end instruments such as the prologue, albeit with only one voice. These are shaped by a state-variable filter with 2-pole, 4-pole, LP/HP/BP settings and fierce resonance, 3 LFOs and modulation, stereo delay and reverb effects. There’s an audio input, too, which can be routed to the effects – but not the filter.

What you get when you’ve first assembled it is a set of four waveforms, which cover all the synth basics you need. Saw, Square, Triangle and variable phase modulation or VPM, plus a preloaded ‘Waves’ user oscillator.

Basic oscillators, Saw, Tri, Sqr, VPM

The basic waveforms sound great for a simple, single-oscillator monosynth. Combined with 3 LFOs and a great-sounding filter, you can get some classic synth sounds without much effort. Control appears limited at first; it takes a few minutes to acclimatise to the way the NTS-1 packs a lot of options into a minimalist interface. A lot of that is down to the one-function per button approach for filter, envelopes and effect slots – the button functions don’t change, which is good, but that means menu diving on a four-character, 8-segment LED display. Talk about going back to the ’80s…

Type, A and B are your main controls. A and B are potentiometers, with start and end points, and Type is an encoder with clicks, making it easy to select items. In the oscillator mode, you’ve got ‘Shape’ and ‘Alt’ controls on A and B. Shape is self-explanatory, and Alt depends on the oscillator – which gets more interesting with user-created oscillators.

For the basic models, it introduces a sub-oscillator, except on VPM where it introduces harmonics and modulation to a basic sine wave. On a prologue, the behaviour of VPM is clearly defined; it’s a little harder to pin down on the NTS-1 but there appear to be 18 distinct modulations alongside the sweep of shapes that alter the sine wave.

There’s an LFO for the oscillator; hold OSC and turn A to set the frequency (F), and B to vary pitch (P) or shape (S). Subtle and silly effects ensue, and the LFO settings persist as you select different oscillators, making it easy to explore sounds.

User oscillators: waves and more

Here’s where ‘what does the NTS-1 sound like’ completely falls apart, as ‘it sounds like the thing it was programmed to sound like’. For an extreme example of this, check out Sinevibes’ ‘Groove’ oscillator – six patches chosen from a pool of 72 presets as a monophonic bassline & drum synth.

That’s a paid oscillator more suited to the bigger ‘logue synths – but there are plenty of affordable and free ones that expand the NTS-1’s budget appeal, and let you get a taste for what it can do before spending more.

Korg include one of their own, Waves, which not only illustrates the flexibility of the small synth straight away, it also illustrates how to edit more complex oscillators. Where the main oscillators sound like the typical set of powerful, bright, soft or harsh synth sounds, Waves is more of a piano/plucked shape with the potential to stretch and shape the sustain and filtering for a variety of tones.

Waves uses two wavetables (plus a sub-oscillator which can be used for ring modulation) – but you only have three knobs and one button! Hold OSC and it displays the LFO setting, but turn Type, and all is revealed – OSC’s LED flashes, and you’re editing the oscillator! Select the parameters and B allows the value to be changed – A remains set to change shape, so you can shape your sound without too much back-and-forth between modes. Once in edit mode you keep selecting parameters with Type – press Osc to exit.

Exploring the sound gives you Wave A, Wave B, Sub Wave, Sub Mix, Ring Mix and Bit-Crush. Because these are adjusted with pots, the values are immediate – there are no presets on the NTS-1. As you might have guessed, using Waves generates some very sophisticated sounds for such a small synth, and the only limitation to ultimate flexibility is the inability to choose the parameter to be modulated.

Delve into the library of sounds developed using logue-SDK and even that limitation is gone. Not all of them are going to become permanent residents, but you’ll find SuperSaw, formant and VA models that work brilliantly. I recommend Oleg Burdaev’s SuperSaw as the first expansion to go for, to get a classic EDM sound, which works well paired with Oleg’s Gator effect.

Duet and Buckets from Hammondeggs are also great, providing musical and familiar starter points before delving into the realms of paid oscillators or ports of Mutable’s Plaits oscillators. The Sinevibes suite shows how these oscillators and effects can be polished for consumer-friendly perfection, and if you want to get a prologue or minilogue in the future they offer a lot of potential.

Filters and effects: NTS-1’s (not so) hidden talents

if you’re new to synthesizers, or have only used modern workstation-style synths with lots of pre-effected patches and built-in reverb, delay and so forth, you’ll be forgiven for thinking that the low-cost analogue monosynths you’ve heard sound terrible. Take something like a Jen SX-1000 or Roland SH-101 and it’s basically beeping angrily at you until you shape the sound.

Filters are part of every complete synth sound, trimming out unwanted frequencies and boosting desired ones, creating effects with modulation and generally being the bit that turns an electronic tone into something creative and musical.

Typically classic synths had ‘a single type of filter’ which contributed a lot to their unique sound and reputation. The NTS-1 has several types – a state-variable filter – that can do Low Pass (trimming high frequencies), High Pass (trimming low frequencies) and Band Pass (allowing you to go backstage… No, wait. Allowing a narrow range of frequencies through). These have 12db or 24db/octave curves (defining how sharp the cutoff is), and the filter is resonant and quite lively with it too, so you can get bell-like to screaming tones as you sweep, as well as flattening and controlling low frequencies.

The filter’s a constant, and available to all oscillators – though some oscillators can introduce a second filter. What you can do with it, though, is driven by the envelope generators – and the mod FX, of which there are many third-party options to bolster the built-in chorus, flanger, phaser and ensemble. Like the oscillator, there are 16 slots for user modules here.

Delay and Reverb are not found in all analogue synths. In fact, even into the ’80s you’d rarely find a synth with effects like this – sometimes, you’d get a chase-play delay, but a proper delay would be the realm of outboard racks or guitar stompboxes. Korg’s included eight slots each for user delay and reverb programs; the library keeps growing with bitcrushers, distortion, gate and loopers. Although you can apply both effects from the built-in pool, you should only use one user delay or reverb at once due to the limits of the NTS-1’s processor.

Crucially, these effect slots are available to external audio as well. The chain runs from mod, to delay, to reverb and you can choose to insert external audio at any stage, or bypass them all just to route through to the NTS-1’s internal speaker.

Presets? Sequencer?

There’s a reasonably sophisticated arpeggiator with several modes, restricted to the input capabilities of the ribbon keyboard of course. As there’s no storage there are no presets, and no means of storing a pattern either; like so many gadgets these days the answer lies in the form of your smartphone and software sequencers.

There are also several ‘editors’ available, though they’re generally ‘dumb’ front ends for MIDI controls and therefore only usable with the built-in oscillators and from a cold start. They can, however, recall presets – such as this CTRLR panel from Momo, which costs less than £6 and includes some presets and a ‘random’ function.

If you’re the sort of person who enjoys making things like this synth, you’ll be fine coping with limitations. But just as an example, look at the selected waveform and the name in the display in the screenshot above…

I want more sounds!

Korg include a bundle of software with the NTS-1, so if this is your first synthesizer you benefit from a few extras you may not already own. These include the LE version of Korg Gadget – a sequencer and package of softsynths – for both desktop and iOS, M1 LE (a software version of the classic Korg synth), some instruments from AAS and Uvi, and Reason Lite – another sequencer/production system.

Although these are all ‘lite’ versions of packages that cost up to £300 each, they’re perfectly useful, worth downloading and have a lot to explore; you could consider the £99 cost of the NTS-1 almost entirely offset by the sounds available across this bundle.

What’s the logue-SDK all about?

Unlike most mainstream synth manufacturers, Korg has opened up some of the NTS-1’s firmware for third-party development as it supports the minilogue xd and prologue as well. So far, it has has proven very successful, with a handful of developers finding a market for paid upgrades (that could be you!) and the bigger synths getting a much larger sonic palette than they would normally have.

It’s a proper software development system though – no ‘drag and drop’ virtual modules, so you’ll either need to know, or want to learn, “C/C++” and how to use a compiler and so forth.

The NTS-1 is an ideal development platform for building oscillators for the larger synths. It’s affordable, polished and usable as an instrument (unlike many ‘dev boards’) and ensures a large market for your work if you create something innovative or unusual.

Is the Korg NTS-1 worth buying as a gift, or for myself?

Buying for yourself? You won’t regret it. It’s a fun distraction to build and justifies the outlay sonically, with only a couple of small niggles that hold it back from greatness.

For synth players, bedroom producers and anyone into electronic genres, it’s brilliant – guitarists might prefer the OD-S tube overdrive pedal kit, and traditional musicians may struggle with the narrow space of the ribbon keyboard (unlike, say, a clearly defined one like that of a Stylophone or CRAFTsynth).

If you’re considering the Korg NTS-1 as a gift for a musician – at £99, it’s not a trivial, secret-santa type of present, however if this is in their style or genre of music it would be a fantastic gift.

Ownership envelope: Korg NTS-1

• Attack – wonderful to build, with diverse materials and an engineering feel, volume is impressive, initial waveforms quite lush and usable
• Decay – fiddly to program with no patch storage, headphone output needs gain and adds noise
• Sustain – oscillator models add interest and unusual sounds, and there’s a steady stream of active development – assuming you don’t start developing some yourself
• Release – build quality means resale is better than some kits, and you’ll probably upgrade to a minilogue xd if you’ve bonded with it. Still useful for effects even if you’ve moved on…

As an addition to an existing studio, it’s really rather lovely to mess with on occasion and – lack of line-level output aside – more than capable of providing a huge variety of useful sounds and inspiration as long as it’s hooked up to some sort of controller. Building it is satisfying as well – not for the challenge, but for the precision of all the parts fitting together and the finish of the completed synth. The satin finish is appealing, and it has a weight and solidity that’s lacking in most similar concepts.

The sound from the internal speaker is equally satisfying. It’s surprisingly clear and loud. Thanks to the headphone output, you’ll need to mess with gain for mixing and recording; not a hardship, but an unusual choice given the work that’s gone into the rest of the kit. Even an internal jumper to select headphone or line output during build would have enhanced longevity for many NTS-1 users.

Ultimately this is a minor point – thanks to the scope of logue SDK, the quality of the components and the effortless ‘cool’ of the packaging and design – no ‘trying too hard to bait hipsters’ here – the Korg NTS-1 is much greater than the sum of its easily-assembled parts.

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