Build instructions for MeeBlip Micro

In this tutorial, we’ll walk step by step through the process of building the Micro board version of the MeeBlip. Keep in mind that, especially if you’re sourcing some of your own components, colors on capacitors and the like will sometimes vary.

If you like to check against a schematic as you work, you can download one:
Get the Hardware Schematics | Direct PDF download

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	1. Unpack all components. Soldering iron, lead clippers and pliers are recommended (click photo for a larger view).
	2. Start with polarized parts – Diodes D1 and D2 (stripe on right).
	3. Clip the leads after soldering.
	4. Install the polarized electrolytic capacitors (negative lead/stripe on the left in all cases). - C1 0.33 uF electrolytic - C2 0.1 uF electrolytic - C3 470 uF electrolytic - C12 4.7uF electrolytic - C14 10 uF electrolytic
	5. Install LED (negative, short lead on the left).
	6. Install Inductor L1 (non-polarized) and the IC5 5V Voltage Regulator.
	7.  Install non-polarized capacitors. It doesn’t matter which lead goes in which hole. - C4 (0.1uF yellow) - C5 (0.1 uF yellow) - C6 (22 pF) - C7 (22 pF) - C8 (0.01 uF blue) - C9 and C11 (470 pF) - C10 (0.001 uF) - C13 (0.1uF yellow)
	8. Next, install the resistors (all are non-polarized). Start on the right side of the board with the power supply and MIDI input: - R1 10K - R2 220 Ohm - R3 1 K - R4 10 K - R5 220 Ohm - R13 100 Ohm (extreme right – by voltage regulator)
	9. Now install the remaining resistors (non-polarized) for the audio section on left side of board. - R6 1 K - R7 274 K - R8 10.7 K - R9 4.64 K - R10 23.7 K - R11 100 Ohm - R12 1 M
	10. Install Q1 (16 Mhz clock crystal) and J1 (3×2 pin ISP programming header).
	11. Install chip sockets, matching the notches to outlines on the silkscreen.
	12. If you’re installing the I/O connectors on the board, solder the audio, MIDI and 9V power jacks in place.
	13. Insert chips. Make sure the notch/dot on the chip goes on the same side as the notch on the socket. Note that the text on the horizontal chips will be upside down. If the pins are spread a bit wide, just press the side of the chip against a flat surface (your workbench is ideal) until they’re at a 90 degree angle from the chip. This will make installation much easier.

That’s it – a fully assembled Meeblip Micro!

Testing your Newly Built Synthesizer

1. Attach a 9VDC center-positive power supply to the 2.1mm barrel jack connector. The LED should light (if it doesn’t, disconnect the power immediately and check that the chips are installed correctly and that all the parts are soldered).

2. If the LED lights, connect the MIDI Out of a controller keyboard to the MIDI In on the Meeblip. Set the keyboard to Channel 1 and play a few notes. The power LED should flash off as notes are received.

3. The Meeblip has a default patch that is loaded at power up. You should hear it when you connect the Audio Output and play a few notes.

Connecting Analog and Digital Controls

Switches (on/off) and potentiometers (10K Linear) can be connected to the Digital and Analog ports of the Meeblip Micro. If the switches or potentiometers are left unconnected, you can still control those parameters using MIDI CC messages (in fact, incoming MIDI CC messages will override the onboard controls).

Digital Switch Mapping:

Digital 1:  Oscillator A Wave (Saw/PWM or Pulse)
Digital 2:  Oscillator B Wave (Triangle/Pulse)
Digital 3:  PWM Enable (Variable Pulse/PWM Sweep)
Digital 4:  OSC B Octave (Normal/Transpose Up)
Digital 5:  Envelope Sustain
Digital 6:  LFO Enable
Digital 7:  LFO Waveform (Triangle/Square)
Digital 8:  Knob Shift (Selects shifted knob parameters)

Analog Knob Mapping:

(unshifted – with Knob Shift off)

P0:  Filter Resonance
P1:  Filter Cutoff
P2:  LFO Rate
P3:  LFO Depth
P4:  Filter Envelope Amount
P5:  Note Glide
P6:  Pulse width / PWM rate
P7:  Oscillator Fine Detune

(shifted – with Knob Shift on)

P2:  Filter Envelope Decay
P3:  Filter Envelope Attack
P4:  Amplitude Envelope Decay
P5:  Amplitude Envelope Attack

MIDI Control Change Mapping

All of the Meeblip Micro’s parameters can be controlled (or overridden) using MIDI CC commands.

The knobs start at CC 48:

CC 48: Filter Resonance
CC 49: Filter Cutoff
CC 50: LFO Frequency
CC 51: LFO Level
CC 52: Filter Envelope Amount
CC 53: Portamento
CC 54: Pulse Width/PWM Rate
CC 55: Oscillator Detune
CC 58: Filter Decay
CC 59: Filter Attack
CC 60: Amplitude Decay
CC 61: Amplitude Attack

The switches start at CC 64:

CC 64: Knob Shift
CC 65: FM off/on
CC 66: LFO Random (off/on)
CC 67: LFO Wave (Triangle/Square)
CC 68: Filter Mode (Low/High)
CC 69: Distortion (off/on)
CC 70: LFO Enable (off/on)
CC 71: LFO Destination (Filter/Oscillator)
CC 72: Anti Alias (off/on)
CC 73: Oscillator B Octave (Normal/Up)
CC 74: Oscillator B Enable
CC 75: Oscillator B Wave (Triangle/Square)
CC 76: Envelope Sustain (off/on)
CC 77: Oscillator A Noise (off/on)
CC 78: PWM Sweep (Pulse/PWM)
CC 79: Oscillator A Wave (Sawtooth/PWM)

A switch is off if its value is between 0-63, on if it’s 64 or higher.