Drawmer DS501 User Manual

DRAWMER

DS501

POWER GATE

OPERATOR’S MANUAL

CONTENTS

SAFETY CONSIDERATION page 1
INSTALLATION page 1
INTRODUCTION page 2
CONTROL DESCRIPTIONS page 4
OPERATION page 6
IF A FAULT DEVELOPS page 11
CONTACTING DRAWMER page 11
TECHNICAL SPECIFICATION page 12
BLOCK DIAGRAM page 13

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COPYRIGHT

This manual is copyrighted © 2001 by Drawmer Electronics, Ltd. With all
rights reserved. Under copyright laws, this manual may not be duplicated in
whole or in part without the written consent of Drawmer.

ONE YEAR LIMITED WARRANTY

Drawmer Electronics Ltd., warrants this product to conform substantially to
the specifications of this manual for a period of one year from the original
date of purchase when used in accordance with the specifications detailed in
this manual. In the case of a valid warranty claim, your sole and exclusive
remedy and Drawmer’s entire liability under any theory of liability will be to,
at Drawmer’s discretion, repair or replace the product without charge, or, if
not possible, to refund the purchase price to you. This warranty is not
transferable. It applies only to the original purchaser of the product.

For warranty service please call your local Drawmer dealer. Alternatively call
Drawmer Electronics Ltd. at [phone]. Then ship the defective
product, with transportation and insurance charges pre-paid, to Drawmer
Electronics Ltd., Coleman Street, Parkgate, Rotherham, S62 6EL UK. Write the
RA number in large letters in a prominent position on the shipping box.
Enclose your name, address, telephone number, copy of the original sales
invoice and a detailed description of the problem. Drawmer will not accept
responsibility for loss or damage during transit.

This warranty is void if the product has been damaged by misuse,
modification or unauthorised repair.

THIS WARRANTY IS IN LIEU OF ALL WARRANTIES, WHETHER ORAL OR
WRITTEN, EXPRESSED, IMPLIED OR STATUTORY. DRAWMER MAKES NO
OTHER WARRANTY EITHER EXPRESS OR IMPLIED, INCLUDING, WITHOUT
LIMITATION, ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. PURCHASER’S
SOLE AND EXCLUSIVE REMEDY UNDER THIS WARRANTY SHALL BE REPAIR
OR REPLACEMENT AS SPECIFIED HEREIN.

IN NO EVENT WILL DRAWMER ELECTRONICS LTD. BE LIABLE FOR ANY
DIRECT, INDIRECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES
RESULTING FROM ANY DEFECT IN THE PRODUCT, INCLUDING LOST
PROFITS, DAMAGE TO PROPERTY, AND, TO THE EXTENT PERMITTED BY
LAW, DAMAGE FOR PERSONAL INJURY, EVEN IF DRAWMER HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

Some states and specific countries do not allow the exclusion of implied
warranties or limitations on how long an implied warranty may last, so the
above limitations may not apply to you. This warranty gives you specific legal
rights. You may have additional rights that vary from state to state, and
country to country.

In the interests of product development, Drawmer reserve the right to modify
or improve specifications of this product at any time, without prior notice.

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DS501 OPERATORS’ MANUAL 1

SAFETY CONSIDERATIONS

CAUTION - MAINS FUSE

TO REDUCE THE RISK OF FIRE REPLACE THE MAINS FUSE ONLY WITH THE SAME

TYPE, WHICH MUST BE A CLASS 3, 230 VOLT, TIME DELAY TYPE, RATED AT 80mA

WHERE THE MAINS INPUT VOLTAGE SWITCH IS SET TO 230 VOLTS AC. AND

160mA WHERE THE MAINS INPUT VOLTAGE IS 115 VOLTS AC. ALL FUSES MUST

COMPLY WITH IEC 60127-2. THE FUSE BODY SIZE IS 20mm x 5mm.

CAUTION - MAINS CABLE

DO NOT ATTEMPT TO CHANGE OR TAMPER WITH THE SUPPLIED MAINS CABLE.

CAUTION - SERVICING

DO NOT PERFORM ANY SERVICING. REFER ALL SERVICING TO

QUALIFIED SERVICE PERSONNEL.

WARNING

TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK DO NOT EXPOSE THIS

EQUIPMENT TO RAIN OR MOISTURE.

INSTALLATION

This product is designed for standard 19" rack mounting and occupies 1U of rack
space. Use four M6 pan head screws to secure the unit into the rack. Fibre or plastic
washers may be used to prevent the front panel becoming marked by the mounting
bolts.
! Care should be taken in the choice of positioning. The unit should not be

mounted where other equipment obstructs the normal air flow.
Avoid mounting the unit directly above power amplifiers or power supplies
that radiate significant amounts of heat.

! The DS501 should not be operated near any water or in a location where

moisture might be present.

DS501 OPERATORS’ MANUAL2

INTRODUCTION

The Drawmer DS501 is a sophisticated dual channel noise gate, which may be used
as two independent channels or linked for true stereo operation. It incorporates a
number of impressive features, many pioneered by Drawmer, which are invaluable
to the sound engineer and not found on conventional noise gates:

! Variable high-pass and low-pass filters for 'frequency conscious' gating.
! Comprehensive envelope control, attack, hold, decay and range.
! Extremely low-noise and low-distortion circuitry.
! Ultra-fast response time.
! Comprehensive side-chain filtering.
! 'Key listen' facility.
! 'Traffic light' display giving clear indication of gate status.
! Signal below threshold indicator.
! Balanced inputs and outputs.
! Peak punch.

AUDIO CONNECTIONS

All input and output connectors are balanced XLRs, with the wiring convention
being: pin 2 hot, pin 3 cold and pin 1 ground. For unbalanced operation, it is
important to short pin 3 of the XLR connector to ground (pin 1) at both input and
output.

Key inputs are made via ¼" mono jack connectors. If the Key jack sockets are
permanently wired to a patch bay, it is important that the patch bay sockets are fully
normalised to prevent random unwanted triggering.

If earth loop problems are encountered, never disconnect the mains earth but
instead, try disconnecting the output signal screen at one end of the cables
connecting the DS501 to the patchbay, we suggest inside the XLR connector itself. If
such measures are necessary, balanced operation is recommended.

DS501 OPERATORS’ MANUAL 3

POWER CONNECTION

If the unit is to be operated at a mains input voltage which is different to that as
supplied, the following must be carried out by a qualified technical engineer.

1: Disconnect the unit from the mains.
2: Using a number 1 size pozidrive screwdriver, remove the seven

self-tapping screws that retain the top cover.

Accessing the internal power switch and fuse

3. Set the voltage rating and
replace the fuse.

4. Replace the cover.

DS501 OPERATORS’ MANUAL4

CONTROL DESCRIPTION

L.F. 25Hz - 3KHZ

The Low Frequency filter works by severely attenuating
frequencies below the cut-off frequency selected.

H.F. 250Hz - 30KHz

The High Frequency filter attenuates frequencies above the
selected cut-off value.
In other words, when both filters are set, it is the range between
the two settings that is allowed to pass.

Note: Filters only effect the signal triggering the gate. See 'KEY
LISTEN'.

Ext/Int In the Int position, this switch causes the gate to respond to the

dynamics of the signal being processed.
In the Ext position, an external audio signal fed to the key input
is used to control the gate, making it possible to gate one sound
using another, independent signal.

Threshold !72dBFs - Infinity

Sets the level at which the gate opens.
The four led meter, to the left of the control, shows the signal
below threshold.

Attack 10uS - 1 Second

This control determines how quickly the gate opens. The fastest
Attack time ensures that the gate does not clip the leading edge
of extremely fast transients.

Note: See section on using Attack under 'OPERATION'.

Hold 10mS - 2.5 Second

Determines the amount of time the gate is held open after the
signal falls below the Threshold.

Decay 5mS - 4 Second

Determines the rate at which the gate closes, once the signal has
fallen below the Threshold and the Hold time has expired.

Range 0dB - !80dB

Sets the amount of attenuation applied to the signal when the
gate is closed. This enables the gate to remove unwanted signals
entirely, or simply to attenuate signals which are too loud.

Note: Active on both channels, even in stereo linked operation

DS501 OPERATORS’ MANUAL 5

Gate/Duck Switches from normal Gating to Ducking, for applications such

as voice-over or the removal of 'clicks' and 'pops'.

Note: See later sections on Ducking under 'OPERATION'.

Key Listen/
Gate/Bypass Key Listen allows the effect of the key filters on the programme

material to be heard at the output.
Gate position is selected for normal use; the filters only affect
the way the unit responds to the incoming programme material ­they do not have any direct effect on the output signal.
Bypass position routes the input signal to the output with no
processing.

Note: To use the DS501 as a filter instead of a gate leave the

switch in the Key Listen position.

Display The famous Drawmer “traffic light” display shows gate status.

Gate Closed Hold Time Gate Open

Peak Punch Adds gain to the leading edge of the envelope for a short

duration. This adds considerable power to the gated signal. A
filter option allows the user to tune the punch to a selected
frequency for more subtle effects.

Note: See later section 'PEAK PUNCH.'

Filter/Full Band/
Out OUT - Peak punch is not used.

FULL BAND - Only the “Level” knob is used. Tune is not used.
FILTER - Both “Tune” and “Level” knobs are used.

Tune 75 Hz - 16 kHz

Controls the frequency band to be “punched”.

Level 1 - 10

Sets the Peak Punch level.

Stereo Link This switch links both channels for two tracking channel

operation, with channel one being master. The trigger source
selected for channel one will actuate both channels' envelopes
when this mode is selected.

DS501 OPERATORS’ MANUAL6

OPERATION

Use the following diagrams as a guide when operating the DS501.

Gating a Kick Drum.

DS501 OPERATORS’ MANUAL 7

Gating a Snare Drum.

Triggering a Bass Guitar from a Kick Drum.

DS501 OPERATORS’ MANUAL8

DS501 OPERATORS’ MANUAL 9

Ducking Music from Vox.

DS501 OPERATORS’ MANUAL10

PEAK PUNCH

Peak Punch is a dynamic feature which
accelerates the leading edge as the gated signal
opens, adding up to 12dB of gain for
approximately 10mS with proprietary release
characteristics.

For percussive material such as drums, fast
synthesised sounds or percussive guitar, the
Peak Punch mode of operation will give the
most dramatic results.
Care must be taken with material which has a
slow attack (especially low frequency bass sounds), as the Peak Punch may produce
transient clicks at the beginning of sounds, unless the attack knob is also slowed.

Filter section (TUNE) is not used in FULL BAND mode.
Set the peak punch LEVEL for added attack. Up to 12dB

is available.

Using the filter to TUNE the punch.
Low pitch frequencies add depth.

High punch frequencies could give a “rim shot” effect on
a snare drum.

DS501 OPERATORS’ MANUAL 11

IF A FAULT DEVELOPS

For warranty service please call Drawmer Electronics Ltd. Or their nearest
authorised service facility, giving full details of the difficulty. On receipt of this
information, service or shipping instructions will be forwarded to you. No
equipment should be returned under the warranty without prior consent from
Drawmer or their authorised representative.

For service claims under the warranty agreement a service Returns Authorisation
(RA) number will be given. Write this RA number in large letters in a prominent
position on the shipping box. Enclose your name, address, telephone number, copy
of the original sales invoice and a detailed description of the problem.

Authorised returns should be prepaid and must be insured. All Drawmer products
are packaged in specially designed containers for protection. If the unit is to be
returned, the original container must be used. If this container is not available, then
the equipment should be packaged in substantial shock-proof material, capable of
withstanding the handling for the transit.

CONTACTING DRAWMER

Drawmer Electronics Ltd., will be pleased to answer all application questions to
enhance your usage of this equipment. Please address correspondence to:

Drawmer (Technical Help line) : Coleman St.: Parkgate : Rotherham : S62 6EL : UK

or, E-mail us on : [e-mail]

Drawmer dealers, Authorised service departments and other contact information
can be obtained from our web pages on http://www.drawmer.com

DS501 OPERATORS’ MANUAL12

TECHNICAL SPECIFICATIONS

(All measurements referenced to +4dBu operating level)

INPUT IMPEDANCE 20KS
MAXIMUM INPUT LEVEL +17dB
OUTPUT IMPEDANCE 50S (bal)
MAXIMUM OUTPUT LEVEL +17dB
BANDWIDTH 23Hz to 31KHz -1dB
NOISE AT UNITY GAIN ref 0dB, GATE open

Wideband 22Hz - 22KHz CCIR ARM IEC A Q-Pk CCIR
AV !90dB !95dB !95dB !97dB !84dB
RMS !88dB !93dB !93dB !95dB

DISTORTION

100Hz 1KHz 10KHz

0dB input < 0.025% < 0.025% <0.025%

POWER REQUIREMENTS 93-125Volt or 185-250Volt at 50-60Hz, 9 Watts
FUSE RATING 80mA for 230Volt, 160mA for 115Volt
FUSE TYPE 20mm x 5mm, Class 3 Time delay, 250 Volt working.

CONFORMING TO IEC 60127-2

CASE SIZE 482mm (w) x 44mm (h) x 200mm (d)
WEIGHT (incl packaging) 3.4 Kgs

DS501 OPERATORS’ MANUAL 13

BLOCK DIAGRAM