Telex DN3600C service manual Introduction

INTRODUCTION

Designed to meet and exceed the needs of the recording, broadcast, installation and live sound industries, the Klark Teknik DN3600 Programmable Graphic Equaliser is an extremely high quality, digitally controlled, two-channel, third-octave equaliser that combines state-of-the-art audio performance with unprecedented ease of use. The two channels may either be used independently or linked for stereo use. To further extend the flexibility of the equaliser, the unit also incorporates variable frequency low and high-pass filters, two notch filters with variable frequency and depth and overall gain adjustment.

Featuring a very large backlit LCD display window, the DN3600 may store up to 66 equaliser programs and the inclusion of a Pro MIDI interface enables several other DN3600s or DN3601 slave units (64 maximum) to be controlled from a single DN3600. The slave units are electrically identical to the DN3600 but have limited control and display facilities. A 16-pin connector is provided for use in conjunction with the DN60/DN6000 Real Time Spectrum Analyser enabling room analysis and equalisation to be accomplished automatically.

The proprietary analogue filters are based around the Klark Teknik “MELT” hybrid filter circuits which offer far greater headroom and dynamic range than is possible using standard 20-bit linear, digital systems. Benefiting from revised circuitry, these filters are exceptionally reliable and offer greater stability than discrete designs. They are also relatively immune to electromagnetic interference, unlike coil-based filters. Separate supply rails are used for the digital and analogue circuitry which, in combination with rigorous internal screening, ensures the cleanest possible audio signal path.

In order to provide maximum operational flexibility, the system includes a switchable Q mode. The Low Q setting (Q:360) provides an accurate emulation of the industry-standard DN360 equaliser. In High Q mode (Q:27), the performance emulates the DN27.

To maintain the optimum signal to noise ratio and headroom at all equaliser settings, the gain control acts on the equaliser sections themselves rather than being a simple pre or post- equalisation gain stage. Additionally, an Auto gain mode is included in the system which automatically scales the gain of the individual equaliser bands as cut or boost is applied to reduce the risk of accidental clipping and to maintain a safe working headroom.

Both the input and output circuitry is electronically balanced with a nominal operating level of +4dBu. The output circuitry is based on the Midas XL3 output stage, giving exceptionally high drive capability. A transformer option is available for both inputs and outputs.

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