Archive for July, 2009

The frontpanel

July 31, 2009


Looking at rotary encoders for the frontpanel and THEY ARE EXPENSIVE.
5€ each, because i’m using a PC keyboard controller to detect panel input, I need the kind that gives pulses on one set of pins when turning CCW and pulses on another set of pins when turning CW.

The alternative is to use potentiometers, a couple of analog multiplexers and an A/D converter. That will definitly be cheaper but a pain to debug.


The rest is relatively cheap, 2 pots for pitchbend and modulation wheels and an XY-joystick for 2 assignable midi-cc inputs.
The pushbuttons cost allmost nothing.


I most definitly need to decide what parameters I wan’t to control from the panel of the keyboard because adding like 50 rotary encoders to the front will set me back for about 250€ and that is a whole lot more than the hardware in this synth costs.

As i’m using a 20 x 4 LCD panel for feedback I can choose to put some of the less frequently used parameters in the display for selection and use just one rotary encoder to change that parameter.



Still doing endurance tests

July 30, 2009

But I think it is holding up, stable as ever.
I like this one. And I must say it is the best I ever built.
It is so much fun just playing it that I almost don’t wanna continue. The sound and feel of it is just awsome. But hey, a VA synth needs those knobs so I’ll hang on.
My grandchild had a go with it and this is the result.

Yes I know I need some better video quality but we are having so much fun with this new keyboard so please forgive the videos at the moment.


Assembly continued (and first test)

July 28, 2009

At the moment, with everything mounted it look’s like this.


With power to the keyboard, MIDI cable attached from keyboard to the soundcard it was time for testing.

And the darn thing won’t boot without a keyboard (the alphanumeric kind of course). I attached a keyboard and all parts where functional.

Time for the fun part, I attached a floppydrive and did the following:

Boot to DOS

FDISK, Format to system disk and reboot.

Removed the CF and attached it to my computer and copied the WIN98 installation folder to it.

Reinsert CF, reboot and installed WIN98 (To further improve this installation I might use LitePC).

Deactivated virtual memory (You MUST do this if your running from CF).

Edit the MSDOS.SYS with AUTOSCAN=0 to get away with no scandisk at boot.

Installed ASIO4ALL V2

F*** and S*** at the same time, NO ASIO OUTPUT! There was ASIO input but the dreaded “Beyond logic” on the outputs. I spent until 8:30 am in the morning trying to get it to work but no success.

After sleeping for 3 1/2 hours I had a cup of coffe and then I disabled the ASIO inputs and the outputs was there 😦 why didn’t I think of that and why can’t they work at the same time?

Installed VSThost and Synth1 v1.07

No trouble at all, both installed without problems.

Attached an audiocable to the soundcard and had a few shots at playing and adjusting the latency and this hardware won’t do more than 4 voices of polyphony depending on the preset.

But I must say that it sounds good, REALLY GOOD!

To show it of  I made a WMV clip (it was late and dark so it’s crappy but the sound is ok).

Now I’m going to tidy up the build and installation and also make some endurance tests to make sure it’s stable.

As Arnold says, I’ll be back.


Assembly begins

July 27, 2009

First the motherboard goes in.


The motherboard has plastic pins (raisers) that was used to mount it into a PC-box. I glue these spacers on the the bottom of the keyboard using SuperSet glue. This glue is strong but still somewhat flexible so that vibration won’t shake it lose.


Next we mount the stuff on the back.


To Host MIDI, Audio connectors and the power switch.


The PSU is a critical component and we DON’T want it to shake lose (High Voltage) so it is both SuperSet glued and screwed into place in the other end of the box, well away from low voltage components.

The fan has too short leads so the will have to be extended before we can mount the fan at the back.


You may also notice the cutoff wire for the mini-keyboard power. We will connect this to the 12 volt power from the PSU. Normaly the keyboard uses a 9 volt power adaptor but raising this to 12 volts does not really matter as there is some 7805  regulator inside and these can take up to 37 volts and 3 volts excess won’t make that much more heat.

Hang on as we continue.


The paint is drying

July 24, 2009

Since  no one of you visitors feel like commenting I guess your not into carpenting 🙂

Let me remind you of what I said in the begining, “Real live playable instruments”,  That is a computer that has been boxed and painted as a musical instrument.

If there are some of you waiting for tips on how to turn your Office PC into something cool, well please hang on, but the thread in this blog is about how to make an instrument and it would make me feel good if you would give a comment.

Anyway here is a peek at the paintjob halfway.



Drilling some new holes

July 23, 2009

The keyboard back needs some holes so I had to make those before painting it.


The holes are from left to right:

Power cable

This was not fun to measure out because the connector is actually mounted on the PSU inside.

Power switch

We need to be able to turn it on and off.

Fan outlet

As this is a computer we need a fan in the casing.


Not even if it’s a fanless Mini-ITX, things WILL get hot and something will eventually break (in a cloud of smoke).

The fan draws hot air out of the box and let new cold air in from beneath the keybord in the front.

Mono/Left Audio out 1/4″-Jack

Connects the Left audio channel from the soundcard to your amplifier.

If nothing is plugged into the Right Audio out, this will be a monomix of both the left and right channel.

Right Audio out 1/4″-Jack

This is obviously the Right Audio out channel.

MIDI To Host

We will use the DB-9 serial port of the motherboard as a Yamaha style “To Host” MIDI port.

You can control the synth from a PC, running sequencer software, through this port with a Yamaha “To Host” MIDI driver.

Now I’m off painting.


Patching up the box

July 22, 2009

To patch up the vectorized hole I use very heavy duty cardboard.

It’s really strong and easy to cut angels in.


We fix the pieces into place using tape.


Building up the corner pieces first.


The tape is just temporary until the glue has dried.


Turning the casing around we armor the inside with a glassfibre mesh to keep the construction together.


Finally we paste glue in all the joints and speckel the glasfibre mesh with glue, making a strong bond for the pieces.


A now we just wait for the glue to dry (That is just so boring 😦 )


As you notice I have added a bar at the top. This will be for supporting the top cover.

It needs sanding, varnishing, sanding, more varnishing and then paint but I won’t show you that, I’m sure you know how to paint.

Do I dare painting it red? Na, that would be pushing it to far. I think I’ll paint it grey with a black bottom (a bit like the emulator 🙂 )

What I really want to do next is starting to mount the hardware into the box and fire up the engine.


Building the box

July 20, 2009

To build the box we need some reference. In this case it will be the keyboard. We lay out the parts against the keyboard and make some marks.


Using a hacksaw we cut out the bottom board and using screws and glue we attach it to the sides.


I have “vector offset” the back of the keyboard. Not really necessary but I like it the Yamaha way. Much more difficult than building it square but nicer looking.


In the same way I attached the back of the keyboard boxing, with glue and screws. We still need to fix the vectorized hole in the box but hang on, we will do that as well.


This casing will take a lot of sanding before going to paint but will look just awsome for a VA synth. Hang on as we patch up the holes and make it look like a keyboard.


Just measuring for fitness but it does appeal, doesn’t it?

You might notice that I don’t tell you any exact measures in this build. That is because I don’t have any.

If you ever watch “Chop Shop” or “American Choppers” on Discovery you know that this is a build that designs the parts as we go along. (Yes I did test the hardware before I begun building the box 🙂 )


Construction begins

July 18, 2009

We need some structural parts. 2 pieces of wood makes the frame together with the keyboard. The wood pieces was cut for a drum-synthesizer a couple of years ago but never used. In this application, turned upside down they will look great, lifting the back of the keyboard into the air.
I have laid out all the parts to make sure they fit in the box.
Here you can see the Compact-flash that holds the OS. It might be to high to fit so perhaps I need to make a flat-cable extension so that I can lay it down.

Some more wooden parts and we can put this together.

I could have built this as a rack box, not needing a keyboard but as I’m a sucker for keyboards since the days of Howard Jones (Have alot of them in my studio) this was not an option.

You can build this one in a 19-inch rack version because the keyboard is just an addon but since a VA-synth needs knobs I like it better in the keyboard version.

Why am I using a mini keyboard? Again, it was what I had. It will make this puppy look really awsome but if you are going to build a synth yourself, use a full size keyboard. There is no (other than nerds) excuse for using a mini keyboard.


So what will we build?

July 4, 2009

When it comes to VA synth’s Nord Lead is a nice one. Novation K-station is another one. Even a third one is the Roland JP-8000 (Should have been the first one). There are lots of others but I would like to model this one after the Nord.

How are we going to get the Nord into this piece of scrap?

I could model it my self as a custom piece of software but then again that won’t give you guys any choice of selecting your favorite synthesizer for your own projects.

So how do we solve this?


By choosing VST as our platform there will be endless options to choose what ever synthesizer sound you want, only CPU power will restrict what instrument you want it to sound like.

But I wanted Nord to be the sound of my VA, what options do I have for a VSTi?

Only one, the Japanese Synth1, a greate reproduction of the Nord Lead in VSTi form and it is free. (Actually I know lots of VSTi’s that will run on this hardware but they cost money) If you build a VA your self, please feel free to choose your favorite VSTi. The thing is that Synth1 runs great on this hardware. (The least demanding VSTi I know of is SampleTank1 but that is not a VA, just a rompler)

How are we going to get VSTi’s running on this hardware?

Well I can answer your question in 3 words… Windows 98, ASIO4ALL and Savihost!

Now I’m going for a week of holiday but when I’m back we will put this baby together, YEAH!