VS1103b MIDI Synthesizer

I published a guide on this a while back, but it was disorganized and scruffy, so here is a tip-top new version with proper photos, diagrams, and a full write-up.

The VS1103b, manufactured by VSLI Technology, is a single-chip MIDI/ADPCM/WAV audio decoder and ADPCM encoder that can handle upto three simultaneous audio streams. It can also act as a MIDI synthesizer.

It is this MIDI synthesizer capability that we are interested in. Make no mistake - the quality of the MIDI voices isn't stunning, but it has a charm to it that reminds me of the FM synthesis found on old Soundblaster cards of yesteryear. The VS1103b MIDI synthesizer mode conforms to the General MIDI standard - 15 melodic channels and 1 percussion channel.

The only problem with this chip however is that it is a very small 48 pin surface-mount package. Fortunately, SparkFun make a break-out board for this chip that has a 20 pin DIP package - much more suitable for DIY electronics.

Here is a video of the VS1103b synthesizer in operation, playing a full multichannel track with drums :

Step 1: Parts list

Passive components
(1x) Dual-gang 10K potentiometer (preferably logarithmic but linear is OK)
(2x) 120R resistors
(3x) 220R resistors
(1x) 1.2K resistor (1K would probably be OK)
(4x) 10K resistors
(1x) 22K resistor
(1x) 100nF ceramic capacitor
(1x) 1uF electrolytic capacitor

Optoelectronics
(1x) 6N139 optoisolator (6N138 is pin-compatible substitute)
(2x) LEDs of your choice

Semiconductors
(1x) 7805 voltage regulator
(1x) BC549 transistor (or pretty much any NPN transistor)
(1x) 74LS00 quad 2-input NAND gate
(1x) SparkFun VS1103B break-out board

Hardware
(2x) 5-pin 180º chassis mount DIN sockets
(1/2x) Audio connector(s) of your choice - I used a stereo 1/4 inch jack socket
(1x) DC power socket and matching power supply (anything between 9V and 12V is fine)
(1x) SPST toggle switch
(1x) Control knob for potentiometer
(1x) Project enclosure
(2x) LED bezels
(4x) Self-adhesive PCB pillars
(2x) 10 pin header strips with matching sockets* (2.5mm pin pitch)
(1x) 8 pin DIP socket
(1x) 14 pin DIP socket
Stripboard (60 holes x 24 tracks)
Stranded-core wire

Comments

[bram69]

Very nice work! Clearly written and innovative design. Thanks for posting this.
I bought one of the last of these from Sparkfun, and I'm trying to build it as a MIDI synthesizer and control it from an Arduino. I don't want to burn out the chip, and I notice the comments on Sparkfun say the VLSI chip must be driven by 3.3 volt commands. You have most things at 5 volts, though, correct? No problems, I guess with using this higher voltage? Also, I am unsure about the purpose of the 74LS00. Is that simply to allow the LED to work properly? Thanks again

[mrjohnson92688]

Excellent tutorial. I am using your design as a stepping off point for adding MIDI to a 1978 Gulbransen Pacemaker Custom Organ.

It is a fully functional organ but it lacks a few sounds that are available in MIDI such as the Tubular Bells and the Square Wave, Sawtooth Wave, etc....

FYI the board you are using is no longer available or in stock from Sparkfun
https://www.sparkfun.com/products/8953

They do have another board available called the Music Instrument Shield. This is normally used to add the VS1053 chip to an Arduino. The chip gives you ACC MP3 and other music functions. It is set up for MIDI in this package.
https://www.sparkfun.com/products/10587

Some Reference Docs:
http://www.vlsi.fi/en/products/vs1053.html
Good info on the VS1053

http://www.vlsi.fi/en/products/vs1103.html
Good info on the VS1103

[Harrymatic]

That's annoying - it makes this guide somewhat obsolete, but thanks for letting me know the board's been discontinued. The Music Instrument Shield will probably be a lot easier to work with and there will be a lot more documentation. If you do want the VS1103b board there are still a few suppliers with stock of it such as ProtoPIC - http://proto-pic.co.uk/breakout-board-for-vs1103-midi-decoder/

[samanpriya]

can buld other vs1103 chip with this synthesizer or spark fun module pre programed one. pls help.
Thank You!

[cupo77]

do you know how much it cost alltogether?

[Harrymatic]

I wasn't really keeping track with this one, but I'd say about £30 (~$40) depending on how nice of an enclosure you get.

[acarrick1]

hello !
first off i'm in love with the idea and sound of this synth!
but i was wondering what would happen if you connected a midi controller to it ?
as i am thinking of building it just for that :)

[Harrymatic]

I've tested this with a keyboard controller and it works just fine, although in your case I would only build this if your keyboard can send MIDI patch changes, as the default piano patch loaded at power-on gets old quick, and there is no way to change the patch directly on the unit.

[reincore]

Great job! Congratulations.
I just wonder, with the final product, how do you actually record something?

[Harrymatic]

The audio output on the back can be connected up to any recording device - such as the line in socket on a PC.

[reincore]

I see. So, practically you can connect the device to a sound card, and then to a computer, and use a DAW to process the recording I guess. But I still don't understand how the device generates sounds - do you do that by sound-mapping it via a DAW?

[Harrymatic]

It uses an interface called MIDI, which is digitally the equivalent of sheet music - it has no sound of it's own but instead the information needed to reproduce music. The VS1103 listens to the MIDI data and outputs audio corresponding to the MIDI notes it receives. MIDI can be sent from a computer, hardware sequencer or just a standard keyboard controller to name a few ways of control.

[Abbaheart]

I have seen the metric unit K for kilo but not R. Like I would see it written as 1K resister. What do you mean by the 120R? Does that mean that is just 120 Ohms? Also I would like to know if A 6n139 OPTOCOUPLER DARL OUT 8-DIP would work. I could not find an optoisolator

Thanks For posting this. I spent $80 on something that did not work on windows 7 64 bit. A midi interface. The fact that it does not need a computer is outstanding. I am really good at electronics so this should be a peace of cake.

Oh and it does not matter if it is perfect. I just need something to play on and practice. Not only that but it is just for fun. Thanks again for posting this.

[Harrymatic]

Yes, the R is just an alternative symbol for Ohms. Optocoupler and optoisolator are interchangeable terms, so the part you have quoted is absolutely fine.

[justinbailey]

Toe Jam & Earl theme! Sweet!

[Harrymatic]

Hats off to you for recognizing it! The TJ&E games had such good music - so funky.

[killerbunny4life]

Can you explain to me how exactly this is a synthesizer?

[Harrymatic]

While VSLI are not specific in the way the instruments are produced, it is most likely a 'rompler' in the sense it just plays back prerecorded samples from ROM.

Wikipedia describes sample-based synthesis as, "One of the easiest synthesis systems is to record a real instrument as a digitized waveform, and then play back its recordings at different speeds to produce different tones. This is the technique used in "sampling". Most samplers designate a part of the sample for each component of the ADSR envelope, and then repeat that section while changing the volume for that segment of the envelope."

As sample-based synthesis is a subset of synthesis in general, I would therefore consider this to be a synthesizer.

[killerbunny4life]

Thanks!

[blinkyblinky]

Wonderful. As well as beautiful.