StringTheory Synth

_MG_7478_thumbStringTheory is a lo-fi, 4-note, paraphonic string synthesizer, based on the Solina String Synth emulation designed and coded by Jan Ostman.

This extremely easy-to-build stand-alone synth delivers a complete, classic poly string synth voice in a tidy desktop package. Based around an Amtel ATMega328 chip this module includes a built-in MIDI input and interface, MIDI Thru, gate out, audio out and controls for envelope, ensemble and modulation.

The synth is designed to fit in a Hammond 1590B die-cast aluminium enclosure (which are widely available in a range of colours) or in our NiceBottom enclosure.

Features

Power 9 to 12V DC adaptor, positive centre pin
Inputs 5-pin DIN MIDI input
Outputs 5-pin DIN MIDI Thru output
Mono 3.5mm Gate Out (approx 5V)
Mono 3.5mm Audio Out
Controls Envelope (combined AR)
Ensemble
Modulation
Other MIDI Learn switch under front panel (accessible via “paperclip port”) sets MIDI Channel and MIDI Note Offset
Gate indicator LED

Audio Demos

First, some raw sounds straight out of the module. Starts with all controls low, then Ensemble and Modulation are gradually introduced.

Using the Gate output to fire an ADSR envelope which in turn shapes a filter on the audio output.

Some notes from lower down the keyboard, again with filter.

Full disclosure… why this synth might not be for you…

This synth won’t be for everyone. If you want an instantly-gratifying, simple string pad that takes up very little space then you’ll probably like it, but even so – it might not be quite what you need.

In the interests of having happy customers (we like happy customers), here’s a list of the pros and cons of this synth so that you can make an informed decision about whether or not it’ll work for you in your system.

Note range

You’ll find that the processor starts to max out at higher frequencies, introducing some audio glitching; dialing back the Ensemble and Mod usually tames this.

It’s not going to be as loud as your raw analog sources

StringTheory outputs at a  couple of dB above line level. This will be too quiet for some, but it’s not as if this is impossible to fix downstream. Again, we considered adding output amplification but we felt that this is a job that is already done (probably much better) by a whole bunch of other gadgets.

If you’re still excited at this point, that’s great, welcome aboard. If not – check back in with us every once-in-a-while, as we’re aiming to address some of the above issues in future versions of this module. Either way – take a listen. We think it’s pretty lush!

Build instructions

The StringTheory Synth build instructions provide a clear guide to making this project.

Parts

The full parts list can be found in the build instructions. All of the parts used in this project are easily and widely obtained from any electronics supplier.

Our parts kits contain all of the electronic parts that you’ll need to do the job; the only things that we don’t supply are:

  • Tools
  • Solder

Prices

Item Price

PCBs and panel

A 2-part PCB set and matching top panel. Includes 4 x 6-32 UNC x 5/8″ machine screws for attaching the panel to an enclosure.

£16.00

PCB, panel & chipset

A 2-part PCB set, matching top panel and an ATMega328P-PU microprocessor, pre-programmed with bootloader and StringTheory software. Includes 4 x 6-32 UNC x 5/8″ machine screws for attaching the panel to an enclosure.

£18.80

Full kit

A 2-part PCB set, panel, pre-programmed microprocessor and all of the additional parts you need to build this project. Includes 4 x 6-32 UNC x 5/8″ machine screws for attaching the panel to an enclosure.

£45.60

Full kit + NiceBottom enclosure

A 2-part PCB set, panel, pre-programmed microprocessor and all of the additional parts you need to build this project. Includes a NiceBottom enclosure kit.

£49.80

Fully assembled

A fully-assembled StringTheory Synth, mounted in your choice of a black die-cast enclosure or one of our NiceBottom enclosures. Just add a DC adaptor and you’re good to go. Please note that lead times will vary – contact us or see the shop for more details.

£85.00 – £95.80

Software update

We intend to continue developing this product and will be releasing software upgrades from time-to-time. For those of you without the kit or skills to update the software yourselves, we’ll release each new version on a new microprocessor – simply swap out the new chip for the old. If you mail us your old chip for re-use, we’ll refund you £2.00

£3.00 – £5.00

Prices include packing & standard (untracked) shipping. All prices are given in GBP, your local price after currency conversion may vary.

All of our products are available from our Etsy shop. Although we make efforts to keep our stock levels as constant as possible, demand might occasionally mean that an item is out of stock. Stock replenishment typically takes less than one week.