Drawmer DS301 Руководство по эксплуатации - Страница 3

Просмотреть онлайн или скачать pdf Руководство по эксплуатации для Усилитель Drawmer DS301. Drawmer DS301 20 страниц. Dual midi expander gate

INTRODUCTION

The DS301 is a highly specified, two-channel expander/gate with greatly

enhanced facilities to augment its performance in both creative and corrective

applications - in any pro-audio environment. It features integral side-chain

filtering, as pioneered in the DRAWMER DS201 gate, and has the benefit of

external MIDI triggering and internal dynamic MIDI note generation in response

to incoming trigger signals.

When triggered by an external MIDI signal, the DS301 responds differently

depending on whether it is set in Expander mode or Gate mode. In Gate mode,

a MIDI trigger, on the specified channel and within the specified note range, will

trigger the gate regardless of MIDI velocity. But in Expander mode, the effect of

MIDI velocity on the dynamics of the audio signal can be varied using the

expander ratio control.

The DS301 may also be used to generate a MIDI note each time the gate or

expander is triggered from an audio source. Additional information is transmitted

as MIDI after-touch following the note-on command. The initial velocity is

dependent on the setting of the Attack control in Gate mode or the amount that

the expander opens in Expander mode. All MIDI parameters are programmed

directly from an external MIDI keyboard or other MIDI controller and may be

stored in non-volatile internal memory if required, without the need to access any

rear panel switches.

Proprietary VCAs have been used to ensure that the audio signal path is clean

enough to satisfy the most discerning of modern recording requirements while the

envelope controls have been enhanced to allow the creation of special effects not

possible with conventional gates.

Despite the additional features embodied in the DS301, the controls are intuitive

and predictable in operation ensuring fast setup in both studio and live sound

situations.

GATES AND EXPANDERS

The main difference between a gate and an expander can best be appreciated if

we consider the case in which the side-chain controls have been set to their

fastest attack and release settings with no hold time. In such circumstances, in

Gate mode, a signal falling below the threshold level would be immediately

extinguished. However, set to Expander mode, the signal is treated differently.

This time, when the signal falls below the threshold level, it is not extinguished

but instead subjected to gain reduction according to the ratio setting of the

expander. This operates very much like a compressor in reverse; with an

expander ratio of 2:1, a 1dB drop in the input signal causes a drop of 2dB in the

output signal level. Signals above the threshold are again unaffected, but for

signals falling below it, the effect of attenuation is more progressive unless a high

expansion ratio is chosen. A gate may be considered to operate in the same way

as an expander with an infinite expansion ratio. The differences between gates

and expander become less apparent when longer attack and release times are

set.

-1-