xfilter Mastering Edition

4-Band Analog Stereo Equalizer

Stereo Link and Precise Control Range

It all started with Bob Katz’s idea of tweaking his own xfilter. So Ruben surely took this pretty serious and spend some time for tweaking components on the circuit board until he and of course Bob were 100% convinced with the overall sound by checking serval recordings in our elysia Class-A Lounge – Studio in Nettetal, Germany.

Now the result: The xfilter Mastering Edition is a very sophisticated, handcrafted analog stereo 4-band equalizer, with both channels linked for stereo operation. All four bands provide a precise control range of +/-5dB.

This fine Stereo Mastering EQ produces the high-end sound of a Class A equalizer at an amazing value for the money. He produces an absolutely precise stereo image based on the use of computer-selected components with extremely low tolerances.

5 reasons why you should use the xfilter Mastering Edition
even there are many more!

Build Quality

The xfilter Mastering Edition, just like all our products, is designed, engineered and handcrafted in Germany.

Class-A Topology

Consequently represents the art of discrete signal processing.

True Stereo Link

As one of the few exceptions in the market, the xfilter processes both of its channels with just one set of controllers – a true stereo linked EQ.

Control Range

The xfilter Mastering Edition offers a precise control range of all four bands of +/-5dB.

Output

Equipped with a balanced output stage with up to +27dBu
 for Mastering purposes.

Build Quality
The xfilter Mastering Edition is all about details.

Every single of its many aspects – sound, features, circuitry, components, design, materials, manufacturing – has been thought over and over until there was just nothing left to improve. Basically, every single part of our fine products is custom, and most of these are made according to our own designs and specs.

Only the best components the market has to offer are good enough for the xfilter Mastering Edition, and it shows. Each of our product is manually built to order and tested by ourselves, here at our headquarters in Germany.

Our product benefits sum up in an audio quality that is beyond all doubt. Even when extreme settings are used, the sound always stays clean and powerful.

The Hard Facts

A special feature of this analog equalizer shines through its double flexibility! It offers high and low shelf bands which can be switched to high and low pass filters with resonance control.

Two bell filters with narrow and wide Q for the mid frequencies as well as additional passive LC stages with shielded coils to refine the treble frequencies.

True Stereo Operation

Using an analog EQ on a stereo buss can be quite tricky, as only very few units offer the possibility to link their two mono channels for true stereo processing.

As a result, the user needs to fiddle around with many knobs in order to cope with the tedious task of matching the settings for both channels as good as possible. The problem gets only worse when the controllers do not have any steps for reference.

But while there are so many compressors in the market that can be linked for stereo operation, why are there almost no EQs which can do this, too? One of the main answers is component tolerances. Obviously, you want the two linked channels to behave exactly the same, but the natural tolerances that especially potentiometers and capacitors have counteract this ideal characteristic.

To make a long story short: The xfilter Mastering Edition solves this problem by using computer-selected dual and quad layer pots as well as special low tolerance caps.

Computer-Selected Potentiometers

In a linked stereo EQ, the potentiometers need a lot of layers. The pots for setting the mixers (gain) have two layers each, while the pots for setting the frequencies even have a total of four layers each!

The problem occurs that every single layer has its own component tolerance, and while layer A could be at the absolute minimum of the allowed tolerance, layer B could be at the absolute maximum. As a result, the filter stages of the left and right channels would not behave the same.

To solve this, every single potentiometer in the xfilter Mastering Edition is measured and selected with an Audio Precision rig and computer routines written exactly for this task. As a result, only 65% of the dual layer pots and only 50% of the quad pots we buy go into production – the rest is put aside.

It’s a true custom shop option we are proud to offer with every xfilter Mastering Edition free of any up-charges.