Category: Hybrid synth

ST4 silkscreens, and the year 2016

Traditionally, there is good news, and there is bad news. This is no exception. So..

Good news, people: the first silkscreen painted casing arrived. See below (click to enlarge). And yes, the power switch is in the Tasty Chips logo 🙂

The first ST4 with silkscreens.

The first ST4 with silkscreens.

Bad news, people: the silkscreen quality isn’t high enough. And this means the delivery will be postponed to next year.

To explain. The silkscreen is spotty and varies in thickness over the plate. We’ll need another iteration to perfect things. Sorry, we just can’t choose to rush this. Especially not on a synth of this class. Which is to say, we will clear this up. No matter the cost!

Now that that’s out of the way. Other news!

Superbooth 2017: April 20..22, Berlin. The most interesting synth fair in Europe. We’re there to demonstrate all our stuff, including formerly classified projects!

In the meantime we’ll keep working on our projects. The ST4 still needs to support more USB keyboard languages 😉

ST4 September update, DIY kits

Just to keep you informed, another ST4 progress update. In the last weeks we’ve tested the sample casing and we’ve requested another one. Two PCB’s didn’t fit correctly, the other 7 did just fine. This will take until early October.

In the meantime all the presets have been added, the DIY manual has been updated with better tables, and we’re ironing out all the firmware bugs. ..And.. we’re finally compiling all the DIY kits. Still, that’s not too much work. The casing is the only real work that’s left. We strive for November, but the planning is now in the hands of the casing factory.. At least you’ll be getting your gear when you spend most of your time indoors. It makes sense 😉

The current collection of kit bags (half of it, actually).

The current collection of kit bags (half of it, actually).

In the meantime we did a minor Sawbench hardware revision (to protect against wrong AC/DC converters) and we’re looking forward to test the 1.2 firmware with its improved VCA/VCF envelopes and improved MIDI support.

Kit bag, with spiffy new label. ;)

Kit bag, with spiffy new label. 😉

When the final casings arrive we’ll start shipping out the kits ASAP! This is done in first-come-first-served order:

1. Kickstarter DIY backers first to last
2. Kickstarter assembled version backers first to last
3. Pre-order list DIY first to last
4. Pre-order list assembled version backers first to last

Today we’ll send out a questionnaire to ask you guys which version you want: rackmount or desktop.. and to ask you for your postal address.

Casing, boxes, and plugged holes

Dear ST4 backers,

This is not the post you’ve been waiting for.. not yet. But we’re close. Very very close.

Today the sample casing was completed.. and it’s on its way here. The casing is without silkscreen paint, but all the metal and powder coating is there. It comes furnished with metal impact standoffs to easily and reliably fit all the electronics. And as you can see the rear electronics can be fitted in two ways, for either:
– rack mount
– desktop

Powdercoated ST4 sample casing.

Powdercoated ST4 sample casing.

Just like we promised. In desktop form the holes on the bottom plate can be plugged. Cover caps are supplied for this. Note that we will ask whether you want the rack or desktop version when the time arrives. And yes, you can still easily switch from rack to desktop or vice versa.

Furthermore, the cardboard boxes were also delivered to our office!

Behold, the box. Behold the official ST4 logo!

Behold, the box. Behold, the official ST4 logo!

Firmware 1.0 is as good as finished. As planned, we succeeded in making LFO and modulation settings per instrument. We’ve included the option to sort 100+ long sample file names. We’ve hit a point where new features just eat a bit too much CPU and/or memory and that means we _have_ to finish up. We’re just doing testing right now, and adding presets!

No telling when the big moment will be there. November seems pessimistic, while mid september seems optimistic. It all depends on if the electronics fit in right away, or we need to move some bits around. The silkscreen paint jobs _seem_ trivial right now, but with the Sawbench, for instance, the color was a big issue for the previous factory. Digital printing turned into silkscreen and in the end that delayed things by 4 weeks.. But we choose quality!

We’re sorry for the delay. We especially underestimated the casings. This is not a small or simple device like the Sawbench, so logically there are more questions, more things to discuss, and more price and feature negotiations. We just didn’t know how much more, exactly. Thank you for your understanding.

ST4 – Electronics production done

All electronics for the ST4 kickstarter have been completed!

All electronics for the ST4 Kickstarter have been completed!

Take a good look. Yes, all those PCB’s have been assembled. And over half of them in-house. That means we just have to hook it all up and test it.

On other fronts: the firmware has progressed nicely. Apple USB keyboards are now supported, German keyboard layout is supported, and it looks like UK is up next. If you have a kayboard layout you want to see supported, you can send it to us and we’ll code it!

USB hubs are (somewhat) supported, which opens doors to new avenues like USB MIDI controllers. The tracker now features half and double speed options. The display has the feature to show multiple controls (up to 4) at the same time, and controls have set points. Huge amounts of features to control the signal path have been added: LFO sync, LFO cross modulation, frequency controllable LFO random noise, channels may be bundled in one big group (for instance, set cutoff for all channels with a single pot). Poly and mono (non-)legato modes are available. There’s now a PWM mode and LFO modulation can control it. That’s not all, LFO can also control bit crusher parameters!

We’re currently negotiating the casing with a number of factories. This is a lot time consuming as previously thought. The ST4 casing is multi-functional (desktop and 19″ rackmount), has a display and this involves a lot of details and choices to be made. When we’ve invested months and months in electronics and software, we’d like to do the same for the casing. We’ll see which ones comes out best. The cardboard box design now also has been done. The DIY manual is 95% finished and the user’s manual is about 70% complete.

In the meantime we’ll continue making the firmware better and better. Most features will be made available through the two onboard rotary encoders, not only through the USB keyboard. The goal is to have everything except sequencing and typing in names possible with on-board controls.

In short, it’s primarily casing stuff and firmware polishing from here on. Late august does seem somewhat feasible.

ST4 Production

In recent weeks the ST4 electronics production has kicked off. Many of the simpler boards have now been produced and are ready to be built into the ST4 units. These were handmade right here at Tasty Chips labs in The Netherlands, just like the Sawbench synth was.

A stash of assembled ST4 VV boards.

A stash of assembled ST4 VV boards.

The more complex boards (exp, vcf, vca) are being assembled by machine in a fab nearby and should be done by the end of the month. Concerning the manual labor, we still have to do the voice and the mod boards. The DIY manual has also seen some major progress and many of the board pages are supplied with photos of all the soldering steps: ST4 DIY resource. More and more detailed information will appear on this DIY resource in the coming weeks.

In parallel, the firmware is still being worked on. Some news:
– Poly mode now works fine and is intelligent enough to allow 3 finger chords + solo.
– The ST4 tracker can now send MIDI out clock signals.
– The ST4 tracker accepts MIDI clock input (preliminary).
– Samples can now be tuned.
– Sample looping can be turned on or off individually per instrument.

The casing (graphic) design is ongoing. We’ve got an excellent graphics artist on board to help us with the silkscreens. The details of the fabrication are being negotiated at the moment.

Last but not least. We’ve had multiple requests whether the ST4 will become available to the public after Kickstarter. The answer is YES! Also, we are taking pre-orders. These are completely free of charge and the interested party is not obliged to buy in any way. Just send your name, postal address, and the version you want (kit, or built unit) to Price for built unit will be 850 eur, 550 for the kit. Units are shipped out on a first-come-first-served basis.

Kickoff t-minus 4 days

The last days we’ve been working feverishly on the ST4 Kickstarter campaign preparations. We’ve already completed a feature-by-feature demonstration last week. This week we’re focussed on making a trailer video, much like the Sawbench one from last year:

But the ST4 more than 4 times as complex as the Sawbench. The feature list is enormous and it’s impossible to even list all features in a minute-long video. So we just have to make the best possible music with the thing..

That ain’t easy, though. We discovered:

* Renoise on Mac exports signed 8 bit WAV, should be unsigned.

* We need way better lighting in the studio to make decent film.

* The ST4 prototype firmware refused to reload the samples from its song.

* Hooking up a full-blown MIDI setup takes time.

Studio demonstration of the ST4.

Studio demonstration of the ST4.

Anyway, we’re good at what we do, and we’re big boys. We’ll manage 😉

Edit: we did, thanks to 20k of filmstudio equipment and professional help!

Developing for the old woodboard, a new screen to display the full LFO MOD matrix.

Developing for the old woodboard, a new screen to display the full LFO MOD matrix.

The coming days we’ll also output some extra video’s: jam sessions and feature-by-feature explanations. There might also be a documentary about STU’s synth/chip history.

STay tuned!

The last of the piggies.

With the year coming to its conclusion, it seems an amusing coincidence that the last Piggy now finally got sold. 🙂 The Piggy was our first synth, a simple and affordable shield that turns your Arduino into an MIDI-driven analog bass synth.

The Arduino Piggyback Synthesizer

The Arduino Piggyback Synthesizer and its host system, the Arduino Uno.

We might do another batch.. The filter would need to be revised (dual gang potentiometers are getting rare!), maybe even changed into the Sawbench VCF.. But we need to know if there is enough demand. The usual address applies Either this or post on Tasty Chips on Facebook or Tasty Chips Forum.

Looking at what’s in store for 2016:

– The ST4. This beast of a synth/tracker has got its own page here: ST4 info page. As said, the Kickstarter will take place in january!

ST4 in its prototype steel casing

ST4 in its prototype steel casing

– The Sawbench mod board: modify the Sawbench to accept external CV for VCF and use and external input signal (If there is enough interest).

– Sawbench firmware update 1.2: including synced LFO, tighter envelopes and possibly exponential envelopes too (If there is enough interest).

– A big analog Eurorack sequencer with 2×16 steps and loaded with features.

– Sawbench VCF/VCA Eurorack module.

– The next polyphonic beast. This will be less channel-driven than the ST4, but will have more channels (yes, that does make sense 😉 ). The focus will be on polyphonic harmonic sculpting..

– The MIDI sequencer (“tracker”) taken from the ST4 released stand-alone, with more controls geared towards pure sequencing.

ST4 woodboard

It’s been a while since anything was mentioned about the upcoming ST4 synth. So, here’s a little post to show the progress of the last months.

The ST4 wood board being operated.

The ST4 wood board being operated.

For those of you not in the know, the ST4 is a multi-channel synth that specializes in rhythm. It’s a hybrid digital/analog system that offers direct control over each track and has a powerful built-in step sequencer. It can do sampling with its on-board mic or from an external source. Samples can be manipulated into arbitrary waveforms, but also standard saw, square and sine waveforms may be used. Noise generators, a wealth of envelopes and per-channel multi-mode filters allow for powerful percussive sculpting.

Our goal is to make this as much a stand-alone system as possible. There’s the usual MIDI connectivity, but there’s also the built-in step sequencer on a large display with full USB keyboard and mass storage support. This makes the ST4 a unique device and as much a studio work horse as something you can take along to your friends or use on stage. The analog VCFs and VCAs give it a warm finish. It’s a Tasty Chips synth: high character and fun to use. 🙂

The current prototype is nailed to a wood board for stability and now has its own AC/DC converter PCB. Almost everything is now on PCB’s (8 in total) and the display is fully integrated into the system. TODO: photo

The GUI is getting more mature by the day. There are little animations for when knobs are turned, the editor allows block functions for copy/paste, transpose, panning, etc. There’s still a lot to be done, but progress is rapid. TODO: anim gif

In terms of performance we can say that the audio quality is as it should be. Also the graphics performance was radically boosted (basically an optimized and specialized version of the UTFT library), and the USB Host driver was completely turned into statemachines, to allow decent multitasking without blocking waits. If anybody is interested in such code for the Arduino Due, just mail us!

There is one performance issue left, however. The potentiometers are spiky, which causes all kinds of glitches in the system. There are ways to reduce this, but we probably need some more weeks to clean this all up. Electro-Magnetic Compatibility (EMC) is a huge can of worms!

To summarize, the ST4 looks like it’s going to be a great product. We aim to release it before Christmas and we might do a Kickstarter before that time.

Feature-complete spaghetti

Loads of things have come our way. Loads of things non-synth. And this took time, loads of time. But here it is, in all its glory: a more-or-less feature-complete model of the ST4:

Feature-complete model of the ST4 in spaghetti form.

Feature-complete model of the ST4 in spaghetti form.



There’s no display connected since it couldn’t possibly fit amidst all this wiring terror, but for the rest, everything just works:

  • All four voices multi-mode VCF action
  • All filters are fully hands-on controllable per voice
  • All four stereo voices VCA action including panning per voice
  • The three ADSR envelopes and two LFO’s are fully controllable
  • Sampling and bitcrushing, voice detuning, voice modes
  • Everything can be controlled by MIDI as well
Action shot of the expansion board.

Action shot of the expansion board.

Next steps are improving performance (loose wires give a bunch of crosstalk, it’s unholy), adding the display and just replacing all that breadboard with a decent PCB… and putting it all in some preliminary casing.

Autumn update: Superpiggie follow-up and “ST4”

Time for a little update after many months of silence on the blog.

Tasty Chips Electronics are still going strong. All the original Piggies have been sold and so we’re going to do a follow-up 😉

The Superpiggy prototype will be a blueprint for this device, although it’s likely it will feature a real VCF instead of a manual filter, along with some other features. The goal is to keep as high a fun-factor as possible, yet also usable as a serious analog monosynth. The product name is not known yet, but there is some idea about the release date: early next year. Also, we will opensource the original Piggy hardware (software was already open), as a sort-of thankyou to the whole Arduino community. 🙂

Meanwhile, the big polyphonic synth project is still ongoing and the prototype is now being integrated with everything on it:
– 3.2″ display
– about 50 knobs
– 4x multi-mode VCF’s
– 4x stereo VCA and mixer
– countless leds and buttons
– MIDI, SRAM, headphone and all other stuff

The ST4 breadboard. Well, part of it..

The ST4 breadboard. Well, part of it..

The SAM3X8E, the micro controller in the Arduino Due, is not powerful enough to control all the analog hardware on its own. A whopping 16 Control Voltages (CV’s) are necessary to control all analog units such as VCF and VCA. So additional PWM IC’s along with output filters were added to the design: these can be controlled by SPI, so the amount of Due pins used there is not high.

Also the display took a huge number of GPIO pins: 21 in total. And all the other devices such as button, potentiometer and led control required many other GPIO pins and analog inputs. All-in-all, the Arduino Due hasn’t got any more pins.. And that’s how we like it: really using the hardware to the fullest, yet keeping it completely transparent for the musician.

Overall, the SAM3X8E and analog electronics now feel like home, just as much as the Atari ST and Falcon once did. This synth, codenamed the “ST4”, will be an ode to those machines of yore. Straightforwardness, directness, fun factor and reliability are the first things we considered. We merge these things we appreciated so much from the early days of computing and computer music with the characteristic beauty of analog audio circuitry; The multi-mode VCF is our own unique design and is very smooth and warm. You’ll love it! 😀

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