C544 Analog Saturation Colour Processor

$268.00 $189.79 ex. VAT

  • Mix and Match HRK 500 Products!
Promo Qty Discount
500 Mix & Match 2 - 3 10%
500 Mix & Match 4 - 5 15%
500 Mix & Match 6 + 20%


C544 | Analog Saturation Processor with 4 Colour Slots

  • Upscale Your Mix with Analogue Vintage Tone
  • 4 Colour Slots per Channel
  • 1:1 Ratio Gain/Trim Colour Drive Circuit
  • +20dB Colour Drive Gain Range
  • Bypass Switch for Each Colour Module
  • +/-6dB Output Trim Gain Range
  • Master Bypass Switch and LED Indicator
  • High-Quality ALPS Potentiometers
  • Studio-Grade Texas Instruments Opamps
  • Balanced Input
  • Balanced Output
  • Compatible with DIYRE Colour Format

The C544 is a Mono Colour Processor with four Colour Module Slots, designed to process the sound with the use of Colour Modules by saturating and adding subtle harmonics to the signal, similar to the harmonics added by the vintage studio equipment.

Each Colour Module stage has Drive/Trim circuit with 1:1 Ratio. The dual potentiometer controls the Drive Gain before the Colour Module and the Attenuation of the output signal from the Colour Module.

As a result, the Colour module Drive Insensitivity increases while the output level remains the same.

Each Colour Module stage has the Bypass Switch which allows the easy A/B operation.

The C544 has the +/-6dB Master Output Trim and the Master Bypass with the LED indicator.

The Master Bypass is located after the Master Output Trim.

The C544 is a must-have addition to your studio setup if you looking for an upgrade from digital plugins.

Active Low Noise Colour Drive Circuit

The C544 has an active Gain Control Circuit. The first half of the Gain/Trim Dual Potentiometer is actively changing the Drive Gain.

Less Drive = less Gain, which means less noise in the background.

Other designs may use a fixed gain drive circuitry, which produces much higher noise floor levels. If more than one fixed gain stages are combined in series, the noise may become audible.

C544 will always deliver the lowest possible noise floor level. The C544 was designed from the beginning to be used by professionals in demanding studio applications.

HRK Colour Modules – True Analogue Plugins!

Colour Modules are Hardware Analogue Plugins made with NOS Discrete Components and Valves which add pleasing harmonics and subtle saturation to the signal, delivering the sonic results of the Vintage Studio Equipment for a fraction of the Price!

Each Colour Module is different and uniquely impacts the sound. You can use the Colour Modules for Recording, Tracking and Mastering.

What benefit I will get from Colour Modules?

The modern DAW systems can produce great results, but most of the sound engineers and music producers will admit that the mix produced with DAW is missing something… some special ingredient, which is the analogue magic.

This is why the big recording studios have racks filled with vintage preamps, compressors and equalizers. The HRK Colour Modules are real Analogue Plugins which will help you to make better recording and mixes standing out from the crowd.

User Manual:

C544 User Manual


The Main FAQ Section

Read more about the Colour Modules Idea – Colour FAQ Section


Item Condition

Brand New, Assembled and Tested.

Every single HRK product is carefully tested with Audio Precision test equipment before the shipping to ensure hassle-free operation.

Payment & Shipping


All Items are dispatched from the European Union within 1-3 working days.

We offer fast worldwide UPS shipping with tracking.

FREE delivery is available for orders over the 249USD to EU, USA and Canada.

FREE delivery is available for orders over the 299USD to Australia, New Zeland, Japan and other destinations.

Please check the shipping cost during the checkout.

Delivery to other WorldWide destinations – 24.99USD

EU Business Customers

All prices exclude the VAT Tax.

If you have the EU VAT number you can purchase the products available in the Bart HRK Shop with no VAT Tax.

Please enter your EU VAT Number at the checkout and the VAT will be deducted from the Total Payment.

Non-EU Customers

Customers from outside the EU can purchase the items with no VAT.

Please select the destination country and the VAT will be removed automatically.

If the VAT is not removed, please email customer service via the contact form and custom invoice will be issued.

Orders from the USA below 800USD are customs tax-free.

Payment Options:

You can pay for your order with any Credit Card



Input impedance: 10kOhm

Output impedance: 100R

Phase inverse: none

Gain: 0dB

All HRK Colour Modules are fully compatible with DIYRE Colour Format

All HRK Colour Processor and Preamps fully compatible with DIYRE Colour Format

All HRK 500 products are fully compatible with API 500 Format