The FAQ – 500 Preamps and Colour Modules


How do I use / connect / power the 500 Units / Preamps / Eqaulizers?

The 500 units (preamps, processors, equalizers, etc.) require the 500 Rack. The 500 Rack provides the necessary power supply and input/output connections. It is impossible to use the 500 modules without the 500 rack.

ALL 500 HRK products are fully compatible with the API 500 standard and with 500 racks which follows the API 500 standard. In another word, the HRK 500 Products will work with most standard 500 Racks.

Will the 500 Module / Rack work in my country with 110VAC / 240VAC?

Most of the 500 racks are equipped with the switched mode power supply which can work with different voltages ranging from 110 to 240VAC. Some older design may have the mains voltage selector switch. The user should read the manual to make sure that the 500 rack can be used in a particular region of the world.

Where do I get the 500 rack?

There are many different manufacturers of 500 Racks. Any major retailer of professional audio equipment should have 500 racks in the offer. It is quite important to make sure that the 500 rack is compatible with the API 500 standard.

What are the Colour Modules?

The Colour Modules are miniature hardware plugins that provide a variety of different tone flavours by altering or saturating the signal.

Each Colour Module is different and uniquely impacts the sound. Some Colour Modules are made with NOS Discrete Components and Valves adding harmonics to the signal, while other Colours are fully functional Equalizer or Compressor.

What benefit will I get from Colour Modules?

The idea of the Colour Modules might be new for some users. However, this is a very easy and effective way to get the sound of the Large Format vintage studio equipment. Because the HRK Colour Modules use NOS discrete components and valves the sonic results are very close to the big studio equipment for just a fraction of the price.

How to use the Colour Modules?

Colour Preamps are required to use the Colour Modules. Colour Modules can plug into the 500 Colour Preamp and processor. The Colour Preamp provides the supply voltages and the input/output signal to the Colour Module. The Colour modules can’t be used without the Colour Preamp or Colour Processor.

How to Control the Colour Modules?

Some Colour Modules have onboard trimmers or jumpers which allow changing some of the parameters of the colour modules. Those parameters can’t be changed from the front panel of the Colour Preamp or Processor. The Colour Preamp front panel controls allow setting the saturation and the output level from the colour module.

Why do I see some level difference between the same type of Colour Modules?

HRK Colour Modules are made with New-Old-Stock components. Some of them were made a long time ago, in the ’60s or ’70s. Every electronic component has a tolerance, resistors, capacitors, transistors, valves, etc…

If you see a small level difference, 1dB or 2dB than it might be caused by the tolerance of NOS components used in the Colour Modules. Some colour modules, such as passive EQ, will have even greater difference due to the tolerance of the trimmers.

It is important to understand that this is normal, as long as you don’t see a major level difference or a high level of audible distortions.

Can I use the HRK Colour Modules with Colour Preamps made with other manufacturers?

YES. As long as the preamp or processor is compatible with DIYRE Colour Format.

Can use the colour modules from other manufacturers in the HRK Colour Preamps or Colour Processors?

YES. As long as the colour modules are compatible with DIYRE Colour Format.

Where can I find the User Manuals?

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