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!

If this is your first DIY project ever, we recommend reading our Getting Started Guide.

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 a problem needs solving, a multimeter can come in handy. You can also use it to sort resistors.

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 of every part in the kit, download and print the Component Sorting Sheet (PDF).

I/O Board Assembly top

Resistors (Bag 1) top

Bend Resistors top

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

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.

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.

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.

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. with tape. Then flip the PCB over and solder in place. Remove the tape.

Populate Bypass Capacitors top

Populate the yellow .1uF capacitors in the positions marked CB, as well as C10 and C11.

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.

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.

Connectors (Bag 3) top

Populate Board-to-Board Connectors top

Place the 32-pin connectors in their positions and fasten them with the included nuts and screws. Then solder and trim.

Large Caps, Inductors, & 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.

Populate Inductors top

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

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.

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.

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.

Colour Duo Drawer Assembly top

Drawer Parts (Bag 0) top

Populate Resistors top

Place the resistors in their respective places, bend the leads, solder, and trim.

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.

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.

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.

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.

Note about 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.

Resistors (Bag 1) top

Sort Resistors top

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

Populate Resistors top

Place the resistors in their respective places, bend the leads, solder, and trim.

ICs (Bag 2) top

Populate Resistors top

Place the resistors in their respective places, bend the leads, solder, and trim.

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.

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. with tape. Then flip the PCB over and solder in place. Remove the tape.

Caps & Diodes (Bag 3) top

Populate Bypass Capacitors top

Populate the yellow .1uF capacitors in the positions marked CB etc. These capacitors are known as “bypass capacitors,” hence the designator CB.

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.

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.

Large Capacitors (Bag 4) top

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.

Cons, SWs, Sockets (Bag 5) top

Populate Board-to-Board Connectors top

Place the 32-pin connectors in their positions and fasten them with the included nuts and screws. Then solder and trim.

Install Switch Caps top

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

Populate Switches top

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

Populate Resistors top

Place the resistors in their respective places, bend the leads, solder, and trim.

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 dries (about 5 seconds)
  • Now solder the rest of the pins of the header from underneath

Daughter Board Parts (Bag 6) top

Populate Resistors top

Place the resistors in their respective places, bend the leads, solder, and trim.

Install Switch Caps top

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

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.

Populate Switches top

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

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 dries (about 5 seconds)
  • Now solder the rest of the pins of the header from underneath

Repeat for channel 2 top

Case Parts (Bag 7) 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.

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.

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.

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.

Mount Daughterboards top

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

Install Lid top

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

Install Rack Ears (Optional) top

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

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.

Install Front Panel (Bag 8) top

Fasten Nuts and Washers to Pots top

Place washers over the pot shafts, then screw on the nuts.

Set Pots to Middle Position top

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

Fasten Pots to Nuts 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.