Colour Operation Manual



As with any electronic device, operating Colour safely requires some common sense and respect for the dangers of electrical power.
  • Treat your Colour like a hair dryer. Don't turn it on when it's wet, only clean it with a dry cloth, and if you spill a liquid on it unplug it immediately and don't turn it back on until it's been repaired by a knowledgeable tech. Don't bring it near the bathtub.
  • Power down your 500-series rack before inserting or removing Colour. Some of the card-edge pads may make contact with the wrong connectors on the backplane during insertion. If the rack is carrying power, Colour and/or your rack may be damaged.
  • Don't attempt to play Operation with your colour. Power down and remove Colour from the 500-series rack before swapping colour modules or adjusting on-board trimmers. Placing your fingers or a screwdriver in a powered module is dangerous to your person and your Colour.

Description and Operation

Colour is an analog signal processor designed to impart the types of sonic artifacts associated with classic pieces of analog recording gear. These artifacts include harmonic distortion, compression, and filtering. As a modular platform, Colour allows the user to compile her own unique signal chain from the spectrum of available "colours." Colour is the first device to put three unique stages of truly analog saturation in one cost-effective and space-saving 500-series module. Colour is designed to interface with balanced, line-level devices. These include professional microphone preamp outputs, AD/DA converter I/O, digital audio interface line I/O, mixing board inserts and aux sends, and other "outboard" processors such as compressors, equalizers, and effects units. Colour can be used during tracking between a mic preamp and recording interface and during mixing as an insert or aux send.

Front Panel Controls

The Colour Palette's controls are designed to be exceedingly simple. Each control is described in greater depth in the "Features" section below. You can download a PDF recall sheet here: Colour 500 Palette Recall SheetColour Palette front panel

Saturation: Adjusts the input level to the Colours

Colour Switches: Engage and disengage (bypass) the three Colours

Trim: Adjusts the overall output level

Block Diagram

Colour's signal flow is exceedingly simple. A balanced signal enters the input and is converted to a single-ended signal by the differential receiver IC. The signal can then be boosted before going to the colours with the Saturation control. The signal then travels through each colour stage in series, just as it would through multiple pieces of gear in an analog recording chain. After the third colour stage, the signal can be attenuated with the Trim control to control the amount of volume being sent to the next piece of gear. Finally, the single-ended signal is converted back into balanced signal by the line driver IC. Colour Block Diagram


Saturation Control

The Saturation knob controls an amplifier which may be used to increase the amount of signal sent to the colours, and therefore the intensity of coloration applied. With the control turned completely counter-clockwise, the amplifier attenuates the signal by 6dB. With the control turned completely clockwise, the amplifier provides 12dB of gain. The space between the two bars on the front panel legend indicate the 0dB gain point, where the signal sent to the colours is equal to the input signal.

    Colour Bypass Switches

    Each colour may be switched in or out of the signal path with its dedicated pushbutton switch. When a colour is engaged, its switch latches in the "in" position and the corresponding LED lights up. When a colour is disengaged, it is removed from the signal path and has no effect on the signal.

      Colour Indicators

      The LEDs next to the colour bypass switches perform the dual functions of identifying the colours installed in the Palette and indicating when the colours are engaged. The hue of each LED is set automatically by the circuitry of the colours installed.

        Trim Control

        The Trim knob provides an adjustable amount of attenuation of Colour's output volume. The Trim may be used to compensate for the gain provided by the Saturation control to avoid clipping the input stage of the next device in the signal chain. With the Trim knob set completely counter-clockwise, the output signal is completely muted. With the knob set clockwise, the signal is not attenuated at all. The Trim control can also be used to turn Colour into an attenuator for too-hot ouputs such as mic preamps without their own trim controls. The space between the two bars of the Trim controls' legend indicates the -6dB point. The unit as a whole is at unity gain when both the Trim and Saturation controls are set to this space between the indicator bars. (Note that if you opted for the Stepped Controls Add-On, that the unit is a unity gain when the Saturation control is set to the space and the Trim control is one click past the space.)

        Using Colour

        While operating Colour is as simple as pushing a button, it, like all good analog gear, rewards those who take the time to learn its secrets. At the end of the day, it will be your ears that dictate the best way to use Colour. But while your ears get to know this new device in-and-out, we offer the following guideposts for using Colour effectively:
        • To use Colour is to practice the art of gain staging. Gain staging is the craft of choosing, arranging, and manipulating the elements of a signal chain to achieve a desired sound. Think of each colour as a discrete piece of analog gear. Like any piece of analog gear, it will behave differently driven hard than when driven moderately, it will be affected by the colour that precedes it, and it will affect the colour following it.
        • Avoid the tempation to "paint" rather than "varnish." Because Colour's effect is subtle by nature, there is a temptation to engage colours and increase the Saturation until the effect is more audible. However, Colour's effects can be most beneficial when they are not perceived as "effects" at all, but rather as an enhancement or heightening of the pleasant aspects already present within the signal. (It's one of the persistent ironies of audio that small amounts of distortion may make a signal sound "more clean.") Engineer Allen Farmello likens this type of distortion to varnish, where "One layer doesn’t do all that much, but many layers add up to a finished sound that anyone can hear and say, “Yeah, that sounds really cool.” The key to achieving a sound that is "finished" without losing it's depth or dynamics is to apply Colour subtly and hear the effect "stack" over many tracks.
        • Experiment. Listen. Repeat. Try engaging only one Colour on every track of a mix. Now try engaging that same colour on only the master mix. How are the effects different? Try engaging all three colours with Saturation half way up. Now engage only one colour and try to match the amount of distortion from before. How are the effects different? Try combining colours in different orders. Record your experiments and listen back blindly with the tracks level matched to see how subtle of a difference you can distinguish. The more intimately you know your colours, the more artfully can employ them.

        Swapping Colours

        Colour's versatility is truly unleashed once you begin to swap and rearrange colour modules. Removing and replacing colours is safe and easy when done properly.
        1. Power down your 500-series rack and remove Colour.
        2. Unscrew the nuts holding the colour(s) you wish to replace.
        3. Pull the colour upwards with both hands until the colour's pins are completely removed from the socket on the Palette.
        4. Align the pins of the colour you wish to insert with the Palette socket and press the colour into place with both hands.
        5. Re-fasten the nuts to hold the colour in place.


        Max. Input Level: +25dBu

        Max. Output Level: +23dBu

        Input Impedance: 24kΩ

        Output Impedance: 50Ω

        Power Requirements: +/-16vDC, 130mA provided by 500-series rack


        DIY Recording Equipment, LLC (DIYRE) warrants this product to be free from defects and will remedy any such defects free of charge according to the terms of this warranty. DIYRE will repair or replace at its option any defective component(s) of this product, excluding the coating and labeling for a period of two (2) years from the original date of purchase. In the event that a particular product is no longer available, DIYRE will replace the product with a similar product of equal or greater value. To make a request or claim under this limited warranty, return your Colour prepaid to DIYRE with a copy of the original invoice. This limited warranty will not apply if the product has been damaged due to abuse, misuse, misapplication, accident, or as a result of service or modification by the user.


        Colour is a electric device intended to be used with properly grounded amplifiers and other audio devices. Connecting Colour to mis-wired or faulty equipement may result in electric shock. The user is responsible for using Colour safely and DIYRE disclaims liability for any damage or injury resulting from the use of this product. If you are not completely sure of the safety of connecting Colour to a certain piece of equipment, consult a qualified technician before proceeding.