From the development period


Droid Newsletter #01 - Medio August 2000

This is a summary of newsletter 01 which was originally in danish.


Welcome to all 20 members of the first newsletter which I, David, will be writing up to the release of Droid 3 keeping you informed of the recent developments as well as afterwards with ideas and inspiration to some hopefully happy Droid owners should you choose to order a Droid 3.


* Droid has 8-bit output, a homemade D/A converter and its sample frequency

is somewhat below 44khz (yet to be calculated by the programmers).

* Preset sounds will be available from as Standard Midi Files -

and we have a very talented guy for this job so don't miss it :)

* The homepage will be updated soon.

* We expect the Droid to be ready for release in a couple of months.

* Pricing has not yet been determined since the prototype is not finished

* Ordering will be possible as soon as we have an exact price.

Droid 3 - why 3?

The Droid project started in 1997 and was originally meant as a birthday present. It quickly evolved since we were all quite surprised of what was achieved with such simple hardware. Also we were excited about what could be achieved by a hardware update and a redesign of the software. This would allow for a much more complex synthesizer at the level of today's synths but with some new special one-of-a-kind features. In this development process both Droid 1 and 2 was dumped and since a lot of people wanted to buy a Droid already when Droid 1 was made we decided to finish Droid 3 with proper casing etc.


Former project coordinator Thor Asmund has left for Japan and it's now up to Rolf Asmund (assistant RISC programmer) and me to sort things out and get everything done for releasing the Droid. We've been working hard on the project the last weeks and we've finally gotten Droid 3 up and running on a real print [*] (thanks to S?ren Greiner). Previously it has been running on a test board [**] that included a Droid 2 for handling midi and audio output.


[**] sort of work print -

Hardcore synth nerd column

Droid 3 has 7 waveforms, two DCOs, two envelopes, a high/lowpass filter and a lot of interesting modes. The programming works almost like with an ordinary synth, but instead of a complex matrix setup table for interconnecting controller parameters you simply just keep increasing the value of e.g. PulseWidth even though it exceeds 255. After 255 the LCD will read things like Pb, Mod, Vel, Aft, En1, DC1 etc. and instead of a static value the current parameter will now obtain its value from one of the matrix sources such as Pitch bend, Modulation, DCO2's output, Aftertouch, Envelope1 or of any of the other matrix sources. This way you can even let DCO1's output control its own Pitch in a sort of feedback loop.

Droid 3's D/A converter is currently locked to the output of DCO1. Therefore you wouldn't immediately assume that the two DCOs could be heard at the same time. However since both DCOs have an offset value which is matrix controllable you can just select DCO1's offset and keep turning the dial untill you reach DCO2's output and voila - you have a mix of the two DCOs coming through DCO1. Also we've made an option for locking the (key follow) pitch of DCO2 to that of DCO1 and at the same time make DCO2's pitch value work as linear detuning. Normally if you detune two identical sounds you'll notice their interference frequency increases the higher notes you play - making it sound like a sample. Linear detuning on the other hand ensures that this interference frequency is the same all over the keyboard making it sound more like a chorus or pulse width modulation. Linear detuning is in fact a totally unique feature as far as we are aware. Furthermore Droid has 3 different ways of overloading. The default is clipping like ordinary distortion, but the two others are quite new. The first one simply mirrors the overloading data turning what would originally have been an overloading upwards peak into a downwards "peak" or better: valley. The second one is for really trashing the sound - this one wraps the overloading data around to the opposite side of the output creating a completely new set of overtones.

And of course I should mention that Droid has the well-known Sync feature retrigging DCO1 at the frequency of DCO2.

When you first check out the Droid it might seem like an ordinary synth but after spending some time with it, you should begin to see (let alone hear) its countless possibilities and complexity. When the first prototype Droid is finished there'll soon be a bunch of new Droid demo-tunes so you can judge for yourself.

See you in the next letter! - keep up the spirit...

Droidful regards

David Filskov

DROID coordinator

If you have any questions or comments or want to unsubscribe from this newsletter, don't hesitate to reply to this mail.

"The best synths are made when competent engineers listen to the consumers."

Droid Newsletter #02 - Primo September 2000


A big welcome to our new members - glad to have you on the list.


* Since newsletter #01 some new Droid 3 demoes have been recorded:

effects: (1796K)

instrumental: (970K)

filter: Should be there when you read this.

* A midi editor for Windows is under development - check it out here:

* Signal/noise ratio approx. 80 dB.

* Pricing and ordering will have to wait a bit longer since we are

still looking into the hardware.


The software no longer has any fatal bugs and we're mostly doing improvements now, putting the features in order of priority to get the most out of the CPU. Until the hardware design is completed we will continue to work on the firmware.

The latest improvements are the filter and the waveform paramter. Filter: It's now not only a lowpass filter but has a highpass mode too (we're working on bandpass and notch but there doesn'to be enough CPU power - I'll let you know if we succeed). Waveform: You can now have the waveform number matrix controlled. This means it's now possible to make a sort of wave-sequencing (a bit like Korg Wavestation) continuously increasing and/or decreasing the waveform number depending on the matrix source. When controlled by a low pitched Saw or an Envelope the waveform chances rythmically. Sounds refreshingly wierd :) - and of course you can also map the waveform to controllers such as modulation wheel, velocity etc.

Hardcore synth nerd column

I wrote in the danish version of newsletter 01 that Droid has two LFOs - this is not quite true. Being matrix controller sources the two DCOs are to be regarded as LFOs due to their wide range of frequency.

Since the Droid internally can handle only positive values, distortion (clipping/mirroring/wrapping) until now, could only occur upwards. However, we have changed the default offset from 0 to 128 and redesigned the algorithms to handle overload in both directions.

We are experimenting with exchanging the RISC-chip with it's "big brother" that has twice as much memory. This enables us to make some cool improvments such as (we cannot guarantee that we will succeed but we will do our best):

a) having the new lowpass and higpass algorithms operating at the same time creating

a bandpass and a notch filter (with controllable bandwidth). It may take too much

CPU load, though, but the high- and lowpass modes are certain.

b) improving the ENVs so that the levels and times can be matrix controlled. This

requires a new table in the EEPROM for which we didn't have enough room earlier.

(We will also try to make a mode for looping the envelopes).

The current envelopes are time based and due to their CPU demand they are only being calculated each time the user changes an envelope value. The new envelopes will not be time based but rate based, thus giving us more CPU for realtime matrix control.

I was planning to describe much more of how the Droid firmware works but since the midi editor's GUI is now available online ( you should take a look at it and hopefully you will get the idea. As you will notice the values to the left of the sliders can be set to any matrix controller source disabling the slider. Currently only envelope values, some of the on/off switches and midi channel (we are infact crazy enough to have considered this, though :) cannot be matrix controlled. All the rest of the features are free for you to modulate as wildly as you like.

In the next newsletter there is going to be some pictures of the LCD-output, and a rough sketch of what the actual Droid 3 will look like (in/out-, dial/buttons/LCD- and LEDs placement. Casing etc. - maybe even a logo).

See you guys soon!

Droidful regards

David Filskov

DROID coordinator

If you have any questions or comments or want to unsubscribe from this newsletter, don't hesitate to reply to this mail.

"The basic principle in good synth making is: Never decide for the user - leave everything up to him."

Droid Newsletter #03 - Medio November 2000


This letter has been delayed a little since I wanted to give you some more goodies of the current development - which has been quite impressive. It was worth the wait.


* A new small demo online here (sync with filter modulation):

* There are some new pictures of the Droid LCD output online here: (scroll down)

* The firmware has been updated significantly.

* Droid output sample rate is approx. 12 kHz - sounds a lot better

than it reads doesn't it? :)

* Estimated release date is now February 2001 (should stick)


At last we have received all the missing parts for the print so that we can now finish the print layout in a couple of weeks. The casing will follow shortly afterwards.

Droid will look somewhat like the SID-station ( only Droid will be black with:


4 buttons

2 buttons mirrored - considering the left handed - there's alot

of left handed sound guys out there, I'm sure.


Negative, backlid - yellowish green (like the fotos) or red

Three LEDs

Red: Output RMS

Yellow: DCO2 rate

Green: Midi input


Jack output

8 bit, 12 kHz, Mono, ~74 dB noise/signal ratio

Midi input

On/off switch

Power input

7.5 -> 9 volts


Good news! - while waiting for the hardware we've done some significant updates on the firmware (we may need to remove one or two options to avoid CPU-overload but it's almost there now):

Independent Keyfollow on each DCO

- No longer forced inter-locking keyfollow between the two DCOs.

Step mode for DCO2 and ENV2

- Set the bit depth on the matrix controller read value. This

will make e.g. a pitch slide sound very un-smooth and very

digital :)

New envelopes

- Matrix controllable - using rates (not times) updated much

faster. Pitch sweeps will sound analogue and snappy and one or

two rates/levels in ENV2 can be modulated in realtime.

Four digital filters

- LP, HP, Bandpass and Notch - aprox. 5 dB roll-off - we hope to

increase that.


- Now both DCOs can be output - with pre-filter boost-option for

overdrive. These structures decide which DCOs are to be run thru

the filter(s). You can even have a HP on one DCO and a LP on

the other - and run the DCOs both thru and past the filter.

Volume resolution increased

- From 16 to (bearly perceptible) 64 stages.

The Matrix controller list currently looks like this:

DC1 = Digital Controlled Oscillator 1

DC2 = Digital Controlled Oscillator 2

EN1 = Envelope 1

EN2 = Envelope 2

Kf = Key Follow

Pb = Pitch Bend

Mod = Modulation Wheel

Vel = Velocity

Bth = Breath controller

Exp = Expression Pedal

C16 = Midi Controller value 16

Pb2 = Pitch Bend double depth

(still room for additional sources)

Droidful regards

David Filskov

DROID coordinator

If you have any questions or comments or want to unsubscribe from this newsletter, don't hesitate to reply to this mail.

Droid Newsletter #04 - Medio January 2000

Welcome once again to the newsletter. I skipped mailing an issue last month. Partly because I was ill and it was Christmas and my... oh well enough of that... I knew some exciting news would arrive this month! - a special thanks goes out to Tim Cocks for his help on the Windows Editor pre-alpha build.


* New pictures of the proto-type Droid print online @

* .exe file and pictures of pre-alpha version of the Windows

editor online @



Good news! We have just recieved the final print from the manufacturer (great work, Lars M?ller) and except for some minor details, everything works like a dream. We are now putting five Droids (without casing) together for development purposes: One for the beta tester, one for the midi editor developer, one for the preset sound programmer, one for the case manufacturer and one for the firmware programmer (whom until now was the only one who had a working Droid and - as you can seen on the Droid lab section of our homepage - this one was in a rather unhandy condition).


As soon as the case design is finished in a couple of weeks, we hope to start selling Droid 3. However, there is one hurdle (mainly for foreign Droid freaks)... the CE approval. We cannot get Droid 3 CE tested before it's completly finished (casing and all). Also, I'm not sure what it is going to cost (the approval), let alone how much time it will take or exactly what is required to pass the CE test - I'm looking into this, though. If all else fails, maybe we can somehow ship the Droid as an (already assembled) do-it-yourself assmebly kit and maybe make it subject to other less strict regulations.

-Web site-

We plan on completely redesigning the homepage, and the new one is going to have a preset (and user?) sounds section with MP3 previews of each sound along with a .mid (standard midi file) and a Windows Droid Editor patchfile.

-Droid programming software-

As it is, recording/sequencing changes to parameters in Droid 3 is quite simple as every feature can be changed using pre-assigned midi controllers. Possibly, though, we hope to get the Droid Editor converted into a VST plugin allowing even easier sequencing and realtime control from within VST supporting sequencers.

We do not at this time have any programmer assigned to this job and we would like to have the VST plugin available for Mac users too - so if you know anybody who would be interested in helping us, please let us know.

We have recieved some requests for Droid support in Buzz Tracker and have found a guy who is willing to give it a try. Thanks and good luck (we heard implementing midi in that tracker should be a real pain in the Buzz).


The Droid CPU has really been pushed to the limit lately due to the complexity of the firmware. Though the schedule is beginning to tighten up and we are still adjusting a lot of details, we are playing with the thought of making an optional simpler mode for gaining higher sample rate. If we can fit this into our schedule we will do so, but don't count on it too much.

Hang on out there - Droid 3 is on it's way.

Droidful regards

David Filskov

DROID coordinator

If you have any questions or comments or want to unsubscribe from this newsletter, don't hesitate to reply to this mail.

DROID Newsletter #05 - Primo March 2001

-Ordering poll-

First I would like everybody on this list to reply to this mail if you are interested in buying a DROID-3. Please note that you will be under NO obligation to actually purchasing the unit by sending us the e-mail. Your mails will be used only to give us a rough idea as to how many DROIDs we should manufacture at this state.

The price almost certainly will be below $300 - shipping and C.O.D. fee excluded (we are expecting a deficit on this DROID project, but you will get your DROIDs, anyhow).


- New homepage design - check it out and see what's coming for

DROID users @

- New DroidEdit for download - this reflects the latest changes

in the firmware (though matrix source depths are still uncertain):

- Final case and print is put into manufacturing and the first

DROIDs should be ready late March.

- A couple of new demos online (described below) (described below)


I will be quite busy in the upcoming weeks with the DROID project closing up - writing the manual, specifications, beta testing, programming preset sounds and maintaining the web site. The next newsletter will probably be released two months from now.

-Hardware & shipping-

The first 15 cases and prints are being manufactured as you read this. When they return around March 20th, we will start assembling the DROIDs right away. The actual shipping will hopefully commence on March 24th.

-Web site-

The web site has been completely redesigned. Here are some of the sections that will soon be available:

- Patches

- Preset sounds in DroidEdit, SMF and MP3-preview format for download.

- Online manual

- Full user's manual - also available in a downloadable version.


- Frequently asked questions about DROID-3.

- Pictures

- See how DROID-3 looks and get a glimpse behind the scenes during development.

- References

- Who are using the DROID.

- User forum

- Learn from other users, share your experiences.

- Newsletter

- All newsletters available online.

- Specifications

- DROID-3 specs...

- Hints & tips (on how to program the DROID-3)

- We share our tips and tricks (and some of yours?) on how to make the

most of the DROID-3. Also you can get answers from the experienced

preset programmer.

- Demos (tunes, fx and instruments in MP3 format)

- Download demo-tunes, show-off fx demos etc.

-Droid programming software-

DroidEdit (for Windows) is coming along nicely and is entering the beta phase in a week. We still have not found a Mac programmer to help us port it to MacOS, but we will keep looking.


The latest features are:

- Matrix sources

Gate (Gat) - Gate is a simple on/off envelope, leaving the real ENVs free.

Velocity Gate (VlG) - Same as Gate, only velocity controls the amplitude.

- Pitch tuning modes

v0.69 had 16 octaves for each DCO and a detune bit turning DCO2's frequency value into linear detuning mode. The newest version (v0.72) has four different sets of these 16 octaves for each DCO. That means you can now choose between linear detuning, logaritmic finetune (+/- half a note), normal pitch tuning (little more than +/- 2? octave) or super wide pitch tuning mode (+/- 8 octaves) individually for BOTH DCOs.

Check out the wide pitch tuning mode here:

Also you should check out the linear tuning mode. I have recorded two saw waves using linear detuning at first, then ordinary (logarithmic) detuning. Both detuning modes sound identical at the lower range, but the higher notes are quite ... unpleasant, when using ordinary detuning. Notice the difference!? :)

- Envelopes

Matrix modulating the envelope rates took up too much CPU but envelope 1 can now loop (level->decay->sustain->release->level etc.) and the offset of both envelopes can be matrix modulated. The current list of matrix destinations is:

Envelope offset,

Filter cutoff,

Filter width (or cutoff2),

DCO amplitude,

DCO pitch,

DCO waveform,

DCO offset and

Arpeggio speed

...and we assure you that this will be more than enough :)

Hold on to your knobs! - we're nearly there and I can hardly wait to hear your comments - let alone your patches (and music?) etc.

Droidful regards

David Filskov

DROID coordinator

If you have any questions or comments or want to unsubscribe from this newsletter, don't hesitate to reply to this mail.

DROID Newsletter #06 - Primo May 2001


Welcome to all our new subscribers from the Elektron mailing list. It is a very exciting time for us now that the interest has almost exploded and we try hard to live up to everyone's expectations (and our schedule).

Newsflash (since newsletter 5)

Homepage updates

- New demos @

- DROID-3 review by the preset programmer @

- Specifications and F.A.Q. is now completed

- DroidEdit - beta v1.1 beta 6 now has MIDI file export

- Preset sounds are now available @


Right now, our preset programmer Sune M. Pedersen is working hard. He will have ready for you more than 300 preset sounds ranging from opera singers, crazy effects, digital flutes and crispy dance organs through dirty sync leads, groovy wave sequences, techno basedrums, snappy zaps and vintage percussions to fat basses and... well, you get the idea.

You can read a bit about Sune and his DROID-3 review here:

I'm personally working on the last bits of info on the web site, testing the MIDI editor, writing the manual and looking into delivery and payment methods.


For those of you who have pre-ordered several months ago, the parts for the first shipment of 15 units have arrived. Except for half of the amount of LCDs which are out of stock. The first six completed DROIDs have already been sold, and we are working closely with the new DROID-owners to catch any last-minute bugs before we start shipping abroad (second batch).

-Next batch-

We hope to be ready to start shipping the next batch at some point in June 2001 - I will keep you informed. I have had my eyes on but I hope we can offer other ways of payment as well. The price for shipment to USA should not exceed $25.

Third batch is scheduled to be ready in August 2001 - all new orders will be added to this batch.


"Everything is proceeding as I have forseen..." and tests on the new print show a significant improvement of the signal-to-noise ratio - probably due to an added ground layer. I guess nobody really cares if a rough and dirty DROID-sound effect is a little noisy or not, but anyway, we are talking approx. 80 dB (using the new mode for disabling the LEDs - see below).

The cases turned out pretty well and we have had positive feeback from the new owners. An assembled unit is pleasantly heavy and rests firmly in your hand or on your desk.


Since newsletter 5, the firmware has been closed for anything other than bugfixes. The last features that have been added are:

- Zero-snap (Zsn)

- a new distortion mode that mutes an overloading DCO

(thus e.g. a 6 dB overloading Saw will be muted half

of its wave cycle).

- Envelope 2 free run

- loop mode for Env2 that ignores keytrigs and keeps

looping just like an LFO.

- Slave Sync changed a little

- now the sync slave retrigs the waveforms each time

the master waveform crosses zero. This means that

not only will the sync master's frequency control

the retrig rate - which is how it usually works -

but the sync master's waveform will in fact have

an effect on the sync "frequency". Quite unique.

- Disable LEDs or LCD off mode

- If you hold down the Enter button while turning on

the power, the LEDs are turned off to minimize

output noise.

- If you hold down the Escape button while turning

on the power, the LCD backlight is turned off to

ehm... well... for fun really.

- DROID-2/MIDI only mode

- If you hold down both the Escape and the Enter

button while switching on the unit, the LCD output,

LCD backlight and LEDs will be disabled on the

hardware side. On the software side, the envelopes,

the filters and DCO2 output will be disabled. This

mode is called DROID-2 mode since the features

resemble those of the simpler (never released)

DROID-2 and allows for a higher samplerate.


The MIDI editor for Windows(tm) has been in the beta phase for some time now and it seems there are no more bugs left. It will be renamed to just v1.1 very soon. Actually we did not plan MIDI export at this point but thanks to Erik S. Andersen we were able to skip v1.0 and go right ahead and release v1.1 including the MIDI export feature.

Droidful regards

David Filskov

DROID coordinator

If you have any questions or comments or want to unsubscribe from this newsletter, don't hesitate to reply to this mail.

"Lesson about life and synth programming: Limitations challenge us - thus creativity grows. Limitations are our reasons to evolve."