Colour Duo Assembly Guide

Safety Precautions, Warranty, and Disclaimer Improper soldering and handling of electricity can cause serious injury and damage to your property. Read and understand the instructions below before beginning your project. Follow the instructions, build carefully, and use the appropriate tools. Build at your own risk. DIY Recording Equipment, LLC is not responsible for any damage or injury resulting from the assembly or use of your kit. You are the manufacturer of your kit. It is your responsibility to turn this group of parts into a working piece of recording equipment. DIY Recording Equipment, LLC does not guarantee the success of your project and disclaims any Implied Warranty of Merchantability. Please visit the support forum for assembly support.
Damaged or Missing Parts All kits and parts are checked before being shipped to you. If something arrives damaged or if your kit is missing a part, please open a support ticket to inquire about a replacement. Missing parts will be replaced at our expense. Damaged parts should be returned for verification. If the part shows signs of use beyond what was necessary to determine that it was damaged, DIY Recording Equipment, LLC reserves the right not to replace the part.

Table of contents

Welcome to the Colour Duo assembly guide.

Thank you for purchasing a Colour Duo!

The Duo is intended for intermediate builders. If you have built a 500-series module or several guitar pedals before you should have no problem with the Duo. However, keep in mind it's a big kit! There are hundreds of parts to place, so plan to split the building over several sessions.

Required Tools top

Soldering Iron
We recommend an adjustable-temperature station, such as the Weller WLC100.

Solder
You can use 60/40 "leaded" solder or lead-free. We recommend 60/40 because it flows better and is easier for beginners to use.

Wire Cutters
You'll need a pair of good "snips" for cutting of the excess leads after soldering.

Optional Tools top

Multi-meter
If you run into problems, a multimeter can come in handy. You can also use it to sort resistors.

Tape
A bit of clear tape will help hold some tricky components in place for soldering.

Desoldering Pump
If you accidentally solder something in the wrong place, a desoldering pump can save the day.

Component Sorting Sheet top

To identify and keep track the resistors, download and print the Component Sorting Sheet (PDF).

I/O Board Assembly top

The Colour Duo is split into two sections, the I/O Board and Drawer. In this guide we'll build the I/O Board first and then the Drawer.

I/O Board Resistors (Bag 1) top

Bend Resistors top

Bend the resistor leads 90 degrees at the body so they can be inserted into the PCB.

Parts in this step: Refer to the component sorting sheet.

Sort Resistors top

Resistor sorting made easy! Enter a value to find the color bands, or enter your color bands to find the resistor’s value. Type in the value of the resistor you need and this tool will show you the corresponding color code.

Place Resistors top

Place the resistors into their respective positions on the PCB. As you place each resistor, bend its leads against the bottom of the PCB so that it stays in place during soldering.

Solder Resistors top

Solder the resistors to the PCB. Observe good soldering technique: heat the pad and lead for 2-3 seconds, apply a small bit of solder, and continue to heat the pad for another 2-3 seconds. The finished joints should be shiny and should have just enough solder to cover the pad entirely.

Trim Resistors top

Use clippers to trim away the excess leads. Clip as closely as possible to the joint without clipping the joint itself.

I/O Board IC, Transistors, Caps, Diodes (Bag 2) top

Populate Transistors top

There are two important things to note about the transistors. First, one side of the body is flat while the other is round. And second, one is a BC327 (black top) while the other is a BC337 (silver top).

Place the BC327 in Q1 and the BC337 in Q2. Place both of them so that the shape of the body matches the shape on the circuit board. Double check the positions and orientation, then solder and trim.

Parts in this step:

Q1
BC327 transistor

Q2
BC337 transistor

Tape and Solder IC Sockets top

Insert the IC sockets so that the notches on the sockets align with the markings on the PCB. Secure in place with tape. Then flip the PCB over and solder in place. Remove the tape.

IC1, IC2
IC socket (x2)

Place ICs in Sockets top

The leads of the ICs must be slightly bent to fit perfectly into the sockets. For each IC, press one row of leads against a flat surface until they form a 90-degree angle with the body of the IC. Then do this for the other row.

IC polarity is indicated by a dot or notch on one side of the body. Align this side with the notch in the sockets. Place all of the ICs in this direction, and press them completely into the sockets.

IC1, IC2
1256 line receiver (x2)

Populate Bypass Capacitors top

Populate the yellow .1uF capacitors in the positions marked CB, as well as C10 and C11. These capacitors are not polarized and can therefore be installed in either direction. After soldering, trim the leads.

CB1-CB4, C10, C11
.1u ceramic cap (x6)

Populate Diodes top

Place each diode so that the line on the component matches the line on the PCB. Double check the orientation, then solder and trim.

D1
1N4004 diode

D2
5.6v zener diode

Populate Small Capacitors top

Place the smaller capacitors in their respective places. These capacitors are not polarized and therefore can be placed in either direction. Solder then trim the leads.

C2, C3, C6, C7
470p caps

Markings: 471

C4, C8
47p caps

Markings: 47j

I/O Board Connectors (Bag 3) top

Populate Board-to-Board Connectors top

Place the 32-pin connectors and fasten them with the included nuts, washers, and screws. The washers should between the bottom of the PCB and the nuts. Then solder and trim.

CON1A, CON2A
Board-to-board connector (x2)

CON1A, CON2A
3-48 Screw (x4)

CON1A, CON2A
Nylon washer (x4)

CON1A, CON2A
3-48 Nut (x4)

I/O Board Large Capacitors, Inductors, and Relay (Bag 4) top

Populate Relay top

Place the relay and bend some of the leads against the bottom of the PCB to hold it in place. Then solder and trim.

U1
24V relay

Populate Inductors top

Place the inductors in their positions, solder, and trim. Inductors are not polarized.

L1-L3
470u inductor (x3)

Populate Large Capacitors top

These capacitors are polarized, so they must be placed in a certain direction. The positive lead is slightly longer, while the negative lead is marked with a stripe on the body of the capacitor. Place the capacitors with the positive lead in the pad next to the "+" marking on the PCB. Double check their orientation, then solder and trim.

C1, C5
100u cap (x2)

C9, C16
100u/63v cap (x2)

C12-C15
2200u cap (x4)

Jacks (Bag 5) top

Populate TRS Jacks top

Place the TRS jacks. Hold them in place with tape or by bending the leads, then solder and trim.

J1, J5
TRS jack (x2)

Populate XLR Jacks top

Place the XLR jacks. Most will snap in place, but you may need to use some tape if they fall out before soldering. Solder the jacks but do not trim the leads.

J2, J6
3-pin XLR male jack (x2)

J3, J7
Combo jack (x2)

J4, J8
3-pin XLR female jack (x2)

J9
5-pin XLR female jack

J10
5-pin XLR male jack

Drawer Assembly top

Active Switch Parts (Bag 6) top

Populate Resistors top

Populate the resistors as in step 1.

R40
2.2k resistor

R41
47k resistor

Populate Diode top

Place the diode so that the line on the component matches the line on the PCB. Double check the orientation, then solder and trim.

D3
1N4004 diode

Populate Relay top

Populate the relay as before.

U1
24V relay

Install Lightpipe Switch Cap top

Position the lightpipe switch cap so that the flat surface faces the bottom of the switch. Then press the cap onto the switch until it snaps into place.


Lightpipe switch cap

SW4
DPDT switch

Populate Switch top

Place the switch and use a small screwdriver to bend a couple of the leads against the bottom of the PCB. Solder and trim.

Populating the Channels top

Since channels 1 and 2 of the Duo are identical, the steps below are written for just one channel. The kit bags are also split up by channel, so there are two of each bag for the following steps. It’s up to you whether you want to build one channel at a time or both at the same time. If you choose to build them one at a time, repeat steps 7-12 for each channel.

Drawer Resistors (Bag 7) top

Sort Resistors top

Here's a link to that same resistor tool from above: Resistor Calculator

Parts in this step: Refer to the component sorting sheet.

Populate Resistors top

Populate the resistors as you did before.

Drawer ICs and Colour Sockets (Bag 8) top

Populate Colour Sockets top

Flip the PCB over and place the 8-pin Colour sockets in their positions. Solder one leg of each socket from the bottom to hold them in place, then flip the PCB over and solder all of the joints. Make sure that you have placed the sockets on the underside of the PCB before soldering!

CON6-CON8
Colour socket (x3)

Populate IC sockets top

Tape and solder the IC sockets as you did before.

IC1-IC5
IC socket (x5)

Populate Diode Bridge top

Place the diode bridge, matching the labeling to that on the circuit board. Bend the leads against the bottom of the pcb, then solder.

BR1
Diode bridge

Populate ICs top

Place the ICs in their sockets as you did before, playing close attention to their orientation. Note that some NE5532 ICs have a dot on the body to indicate pin 1 instead of a notch. In this case, orient the ICs so that the dot on the IC aligns with the notch on the IC socket.

IC1
1512 mic preamp

Markings: THAT 1512

IC2-IC5
NE5532 opamp (x4)

Markings: NE5532P

Drawer Capacitors and Diodes (Bag 9) top

Populate Bypass Capacitors top

Populate the bypass capacitors as you did before.

CB1-CB10
.1u ceramic cap (x10)

Populate Diodes top

Populate the diodes as before, paying close attention to the black lines for orientation.

D1, D2
1N914 diode (x2)

Populate Remaining Small Capacitors top

Place the remaining capacitors in their respective places. As before, these capacitors are not polarized.

C4
82n cap

C6-C8
22p cap (x3)

Drawer Large Capacitors (Bag 10) top

Populate Large Capacitors top

Populate the large capacitors as you did on the IO board. Remember that these are all polarized and must be placed in a particular direction.

C1, C2
100u/63v cap (x2)

C5, C9
100u cap (x2)

C3
3300u cap

Populate Bug Fix Capacitors top

These two capacitors have been added to the kit to fix a bug where, in rare cases, IC1 will fail when the drawer is plugged and unplugged.

Before placing the capacitors, bend their leads so that they have approximately the same spacing as the distance between the +16v, Gnd, and -16v test points near U1. Then place the capacitors in the test points with the positive lead of in +16v, the negative lead of the other in -16v, and the remaining leads of both in Gnd. Solder and trim the capacitors.

N/A
220u cap (x2)

Drawer Connectors, Switches, and Sockets (Bag 11) top

Populate Board-to-Board Connector top

Place the 32-pin connector and fasten it with the included nuts, washers and screws. The washers should between the bottom of the PCB and the nuts. Then solder and trim.

CON1B/CON2B
Board-to-board connector

CON1A, CON2A
3-48 Screw (x2)

CON1A, CON2A
Nylon washer (x2)

CON1A, CON2A
3-48 Nut (x2)

Install Switch Caps and Populate Switches top

Press the caps onto the switches. This may require a bit more force than you’d expect.

Place the switches and use a small screwdriver to bend a couple of the leads against the bottom of the PCB. Solder and trim.


Switch cap (x3)

SW1-SW3
DPDT switch (x3)

Quick Question top

Which additional features of the guide are you using?


Yes No

Yes No

Populate Header Sockets top

Since these sockets will mate with pins on the daughterboard, it’s important to mount them exactly perpendicular to the circuit board. Our preferred technique for this is as follows:

  • Solder a single pad in the middle of the header’s footprint
  • Place the header and press gently against the solder joint, while heating the edge of the soldered pad
  • After the solder liquifies and the header snaps into place, remove the soldering iron and hold the header in place until the solder cools (about 5 seconds)
  • Now solder the rest of the pins of the header from underneath

CON3, CON4
12-pin socket (x2)

CON5
6-pin socket

Populate Potentiometers top

Pay close attention to the values marked on the back when placing the potentiometers (pots). Place them, then double check the values on the pots against those on the PCB. Bend two leads of each pot against the PCB, then solder and trim.

VR1
C1k pot

Markings: C1k

VR5
B10k pot

Markings: B10k

VR2, VR3, VR4, VR6
B20k pot (x4)

Markings: B20k

Drawer Daughter Board Parts (Bag 12) top

Populate Resistors top

Populate the resistors as before.

R1_DB
47k resistor

R2_DB
100k resistor

Populate Header Pins top

As with the header sockets, these pins must be perpendicular to the board to mate correctly. Follow the same technique:

  • Solder a single pad in the middle of the header’s footprint
  • Place the header and press gently against the solder joint, while heating the edge of the soldered pad
  • After the solder liquifies and the header snaps into place, remove the soldering iron and hold the header in place until the solder cools (about 5 seconds)
  • Now solder the rest of the pins of the header from underneath

CON3_DB, CON4_DB
12-pin header (x2)

CON5_DB
6-pin header

Install Switch Caps and Populate Switches top

As you did before, position the lightpipe switch cap so that the flat surface faces the bottom of the switch. Then press the cap onto the switch until it snaps into place. Also install the black switch caps on the remaining switches.

Then place and solder all the switches.


Switch cap (x2)


Lightpipe switch cap (x4)

SW1_DB-SW6_DB
DPDT switch (x6)

Chassis Assembly top

Chassis Fasteners (Bag 13) top

Insert Drawer Rails top

Position the drawer rails on the inside of the case with the wider opening facing the front of the case. Then snap them into the holes indicated above.

PCB rail (x2)

Fasten IO Board to Case top

Mount the assembled IO board to the case. You will need to tilt it slightly to get the PUSH tabs of the XLR jacks through the holes first. Then fasten the nuts and washers to the TRS jacks, and screw in the mounting screws for the XLR jacks.

XLR screw (x16)

Install Nut Plates top

Place each nut plate behind one of the flanges at the front of the case, so that the holes line up with those on the flange. Then fasten them to the case with the included screws.

Nut plate (x2)

Nut plate screw (x4)

Install PCB Support Brackets top

Place each L-bracket over the pots of the Colour section. Check that the standoffs on the brackets align with the holes in the PCB. Then fasten the brackets to the motherboard via the screws and standoffs. Use standoffs for the three holes closest to the front of the circuit board, and screws for the rest.

PCB bracket screw (x8)

Standoff (x6)

Mount Daughter Boards top

Plug the daughter boards for each channel into the two sets of header sockets. Then screw them to the support standoffs.

PCB bracket screw (x6)

Install Lid top

Place the lid on the case with the countersunk side facing up. Then screw it to the case.

Lid screw (x7)

Install Rack Ears (Optional) top

If you plan to use your Duo in a rack, screw the rack ears to the case.

Rack ear screw (x6)

Apply Rubber Feet (Optional) top

If you plan to use your Duo on a desktop, you may choose to apply the rubber feet to the bottom of the case. Keep in mind that you will need to remove them later if you want to use the Duo in a rack with another unit directly below it.

Rubber foot (x5)

Front Panel (Bag 14) top

Fasten Nuts to Pots top

Place the front panel over the pots and switches (yes, this might be the trickiest part of the build). Place washers over the pot shafts, then screw on the nuts. Note that depending on variations in the length of the threads on the pots and nuts, you may not be able to fit the washer under the nut. In this case, just leave the washer off and fasten the nut directly to the panel.

Pot washer (x12)

Pot nut (x12)

Set Pots to Middle Position top

To prepare for adding the knobs, set all the pots to the middle position (10 clicks in).

Fasten Knobs to Pots top

Place the wider, skirted knobs on the two preamp gain pots, and the non-skirted knobs on the rest of the pots. Orient all of them so that the indicator line points precisely to the 12 o’clock position. Then fasten the knobs to the pot shafts by tightening the set screws with the included hex wrench.

Skirted knob (x2)

Non-skirted knob (x10)

Insert Drawer into Case top

Insert the drawer PCB into the PCB rails, then slide the assembly into the case. There should be some resistance at the end when the board-to-board connectors mate. Then fasten the front panel to the case by tightening the thumb screws.

Final Checks top

    Before you wrap up, check the following things:

  • Capacitor orientation: Is the stripe on the cap on the opposite side from the "+" marking on the PCB?
  • Diode orientation: Do the stripes on the diode match those on the PCB?
  • IC orientation: Does the dot/notch on the IC align with the notches on the socket and PCB?
  • Resistors: Are all the resistors in the correct positions?
  • Transistor orientation: Does the shape of the transistor match the outline on the PCB?
  • Soldering: Is every solder joint shiny and clean? If one is cloudy or misshapen, try reheating it for 8 seconds and adding a tiny bit more solder.
  • Trimming: Are all of the excess leads trimmed down as close to the joint as possible?

Optional: Run Audio Tests top

If you're unit powers up and passes audio fine, most likely it's functioning exactly as it should. But if you want to really be sure, follow the steps in this video to test your Duo with the free software Room Eq Wizard (REW) and your interface:

Colour Duo Audio Test Process (YouTube)

If you are unfamiliar with the software, please watch our series of videos on measuring gear with REW:

Measuring Your Audio Gear with REW (YouTube Playlist)

Finished! top

All good? Congrats on finishing your build! Have a question or problem? Drop us a line.

Help Us Improve top


1 2 3 4 5 6 7 8 9 10



Creative Commons License Manual by DIY Recording Equipment, LLC licensed under a Creative Commons Attribution 4.0 International License.

Privacy Policy