Schertler DAVID X User manual

MANUAL
WWW . S C H E R T L E R . C O M
DAVID X
COMBO AMP FOR ACOUSTIC INSTRUMENTS
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•USER•
V1 EN

ACOUSTIC XAMPS

INTRODUCTION
3
Thank you for choosing the DAVID X amplier. DAVID X represents the state of the art in Swiss
amplier design, reecting all the needs of the user. Offering a signicantly improved power amp
and speaker section, together with a crossover lter network, limiter and gain, this amp provides
120 W (112 dB SPL) of bi-amplied analog power. DAVID X is equipped with a 1” dome tweeter
and 6” woofer. It has been engineered with an optimized 2-way bass reex system.
DAVID X is ideal for those seeking no-compromise acoustic instrument amplication. An effective
system for practice and home studio use, DAVID X’s size also makes it the most portable and exible
SCHERTLER amplier model. The three inputs can accept two instruments, or an instrument and a
vocal microphone, plus a stereo playback device.
SCHERTLER amps feature a sophisticated Class-A preamp with no integrated circuits and No
Negative Feedback (NNFB), resulting in unparalleled dynamics and fast transient behavior.
To make the most of your DAVID X amplier and to ensure trouble-free operation, please read this
manual carefully before using the amp for the rst time. We also advise keeping the manual for
future reference.

ACOUSTIC XAMPS
IMPORTANT SAFETY
INFORMATION
SAFETY FIRST!
Safety is of major importance when operating any electrical equipment,
so please note the following:
On a product, a lightning ash within a triangle indicates the presence of
uninsulated “dangerous voltage” within the product enclosure. This may
be of sufcient magnitude to cause risk of electric shock.
ELECTRICAL SAFETY
Before connecting your amplier to the mains, make sure that the mains voltage does not
exceed the voltage specied on the device.
Do not use your amplier if its mains cable or plug are not in perfect condition. Replace these
as necessary. The replacement cable must be the same as the original.
Your amplier should only be connected to a mains socket with a ground protection system.
When using or installing your amplier, make sure that the mains socket and the amplier’s
mains cable and plug are easily accessible.
Do not, under any circumstances, defeat the safety purpose of the polarized or grounding-type
plug. A polarized plug has two blades with one wider than the other. A grounding-type plug
has two blades and a third grounding prong. The wide blade and third prong are provided
for your safety. If the supplied plug does not t your mains socket, consult an electrician for
replacement of the obsolete socket.
Do not expose your amplier to rain or any other water (even in small amounts). Do not use
the amplier near water.
Avoid spilling drinks or any other liquids on the amplier.
Do not operate your amplier in excessively humid conditions. Avoid excessive heat from
sunshine, re or similar. If the amp is being used in a dusty environment, make sure it is
adequately protected.
Avoid using or installing your amplier near any heat sources such as radiators, heat registers,
stoves, or other heat-producing apparatus. Do not put any sources of open ame (e.g. candles
or pyrotechnics) on or near the amplier.
Do not cover your amplier during use, or obstruct the ventilation ow in any way.
Always leave sufcient clearance between the heat sink and any other surface.
Unplug your amplier during lightning storms, or if it is not going to be used for a while.
(Remove the plug from the mains socket to completely disconnect the amplier.)
Your amplier does not contain any “user serviceable” parts. Servicing and/or repairs should
only be carried out by qualied personnel. See MAINTENANCE AND REPAIR.

5
OPERATIONAL SAFETY
During live performances or installation, make sure that your amplier’s mains cable cannot be
walked on, tripped over or “pinched” – particularly at sockets, around waste bins etc.
To avoid interference, do not use or install your amplier near power transformers, TV sets, RF
transmitters, electric motors, or any other sources of electrical energy.
To avoid potential accidents, only use attachments, accessories and other equipment such as
carts, stands, tripods, brackets or cases that are specied or recommended by the manufacturer,
or sold with your amplier.
Loud volume levels can cause irreparable damage to both the device and your hearing, so
avoid the following while using your amplier:
- acoustic feedback (never point microphones directly at a loudspeaker)
- high levels of distortion
- impulse noises (loud “pops”) that can occur when a device is switched on/off, connected to
or disconnected from a system.
MAINTENANCE AND REPAIR
Your amplier can be carefully cleaned, as necessary, using a dry cloth. Do not use water.
When cleaning, do not use any solvents (such as acetone or alcohol). These could damage the
amplier’s nish and its labeling.
Visually check your amplier on a regular basis for any signs of wear and tear or damage, but
do not attempt any kind of servicing or repair.
If your amplier malfunctions, or is damaged, e.g. if liquid has been spilled or objects have
fallen inside, the amp has been exposed to rain or moisture, does not operate normally, or
has been dropped, please call your nearest SCHERTLER technical assistance center. (For more
information, you can contact us at the address on the last page of this manual.)

ACOUSTIC XAMPS
Class–A High Voltage Preamp / No Integrated Circuits / No NFB
SWISS
MADE
1 3
INSTRUMENT IN STEREO IN
2
10V GAIN WARM LOW MID HIGH REV VOLUME
MASTERDI OUT
GAIN RESON LOW MID HIGH REV VOLUME
flat
INSERT REVERB
master
LINE OUT
DAVID X
GND LIFT
INSTRUMENT INMIC IN P24 10V
DAVID X 1 2 0 W A T T
A C O U S TIC
A M PLI F I E R
SER IAL NUM BER
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8 0 W A T T P O W E R C O N S U M P TIO NX S E R I E S
CAUTION
RISK OF ELECTRIC
SHOCK
DO NOT OPEN
TO REDUCE RISK OF FIRE,
DO NOT EXPOSE THIS
EQUIPMENT TO RAIN
OR MOISTURE. FOR
CONTINUED PROTECTION
AGAINST RISK OF FIRE,
REPLACE ONLY WITH THE
SAME TYPE AND RATING
OF FUSE.
240 Hz
150 Hz
1.1. INSTRUMENT IN: An unbalanced input for the connection of 1/4” jacks, with optimal sensitivity
for high level signals. The electronics will adapt to any situation - no special action is required.
1.2. 10V: This supplies the jack connector with 10 VDC for powering electret microphones.
1.3. GAIN: This variable gain preamplier adjusts the sensitivity level to ensure the best possible
processing of the signal through the channel. It is important that this input level is set and optimized
in the best way to achieve the cleanest sound possible.
1.4. OVERLOAD: This LED (when lit) indicates that the level of the input signal is too high and it
might therefore introduce distortion.
Practical tip: When using an amplied speaker, distorted input signals should be avoided at all cost
in order to prevent potential damage to the speaker. While playing your instrument, carefully set the
preamp/gain level by turning up the GAIN control until the OVERLOAD LED begins to blink. At this
point, turn the gain back down slightly. Now set the MASTER Volume between 30% and 60%. With
the gain and master levels appropriately set, you can now set the channel volume as you please.
1.5. WARM: When active, this low-pass lter dampens higher frequencies to produce a warmer
sound when using bridge-mounted pickups such as the SCHERTLER STAT Series for violin, cello and
double bass.
1.6. HIGH, MID, LOW (EQ): These controls are for high, mid and low frequency regulation. Offering
cut and boost of ±15 dB, they allow a wide range of tonal variations to be explored. When the
controls are positioned centrally there is no cut or boost of the selected frequency band.
1.7. REVERB: This rotary control sets the level of the digital reverb on the channel.
1.8. VOLUME: This rotary control regulates the channel volume.
1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8

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Class–A High Voltage Preamp / No Integrated Circuits / No NFB
SWISS
MADE
1 3
INSTRUMENT IN STEREO IN
2
10V GAIN WARM LOW MID HIGH REV VOLUME
MASTERDI OUT
GAIN RESON LOW MID HIGH REV VOLUME
flat
INSERT REVERB
master
LINE OUT
DAVID X
GND LIFT
INSTRUMENT INMIC IN P24 10V
DAVID X 1 2 0 W A T T
A C O U S TIC
A M PLI F I E R
SER IAL NUM BER
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8 0 W A T T P O W E R C O N S U M P TIO NX S E R I E S
CAUTION
RISK OF ELECTRIC
SHOCK
DO NOT OPEN
TO REDUCE RISK OF FIRE,
DO NOT EXPOSE THIS
EQUIPMENT TO RAIN
OR MOISTURE. FOR
CONTINUED PROTECTION
AGAINST RISK OF FIRE,
REPLACE ONLY WITH THE
SAME TYPE AND RATING
OF FUSE.
240 Hz
150 Hz
CONTROLS
2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11
2.1. MIC INPUT (XLR): This input is electronically balanced for XLR-type connections. The channel is
designed for any kind of microphone source e.g. dynamic and condenser mics.
2.2. INSTRUMENT IN: An unbalanced input for the connection of 1/4” jacks, with optimal sensitivity
for high level signals. The electronics will adapt to any situation - no special action is required.
2.3. P24: Phantom power supplies the XLR connector with 24 VDC for powering condenser
microphones. Most condenser (and dynamic) mics, and some preamps, can be safely phantom
powered. In certain cases however, phantom power can cause damage. This tends to happen with
unbalanced microphones, preamps, or stompboxes that have been modied for balanced XLR use.
If in doubt, please contact the manufacturer to check the compatibility of your audio device before
using the amplier.
2.4. 10V: This supplies the jack connector with 10 VDC for powering electret microphones.
2.5. GAIN: This variable gain preamplier adjusts the sensitivity level to ensure the best possible
processing of the mic/instrument signal through the channel. It is important that this input level is
set and optimized in the best way to achieve the cleanest sound possible. (See “Practical tip”, 1.4.)
2.6. OVERLOAD: This LED (when lit) indicates that the level of the input signal is too high and it
might therefore introduce distortion. (See “Practical tip”, 1.4.)
2.7. RESON: The RESONANCE (notch) lter cuts the frequency of 150 Hz/240 Hz, to reduce low-
frequency feedback. Left: no attenuation (at), Right: maximum attenuation.
2.8. RESON button: Use the RESON button to select the resonant frequency of the instrument
(240 Hz/150 Hz).
2.9. HIGH, MID, LOW (EQ): These controls are for high, mid and low frequency regulation. Offering
cut and boost of ±15 dB, they allow a wide range of tonal variations to be explored.
When the controls are positioned centrally there is no cut or boost of the selected frequency band.
2.10. REVERB: This rotary control sets the level of the digital reverb on the channel.
2.11. VOLUME: This rotary control regulates the channel volume.

ACOUSTIC XAMPS CONTROLS
Class–A High Voltage Preamp / No Integrated Circuits / No NFB
SWISS
MADE
1 3
INSTRUMENT IN STEREO IN
2
10V GAIN WARM LOW MID HIGH REV VOLUME
MASTERDI OUT
GAIN RESON LOW MID HIGH REV VOLUME
flat
INSERT REVERB
master
LINE OUT
DAVID X
GND LIFT
INSTRUMENT INMIC IN P24 10V
DAVID X 1 2 0 W A T T
A C O U S TIC
A M PLI F I E R
SER IAL NUMBER
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8 0 W A T T P O W E R C O N S U M P TIO NX S E R I E S
CAUTION
RISK OF ELECTRIC
SHOCK
DO NOT OPEN
TO REDUCE RISK OF FIRE,
DO NOT EXPOSE THIS
EQUIPMENT TO RAIN
OR MOISTURE. FOR
CONTINUED PROTECTION
AGAINST RISK OF FIRE,
REPLACE ONLY WITH THE
SAME TYPE AND RATING
OF FUSE.
240 Hz
150 Hz
3.1. STEREO IN: 1/8” mini jack stereo input for PC, MP3 and other electronic devices. Volume
depends on the MASTER volume regulation.
4.1. DI OUT: A general XLR balanced output for connecting to external systems. The output volume
does not depend on the regulation of the MASTER control, but is affected by changes in individual
channel volume.
4.2. DI OUT VOL: This rotary control sets the output level on the DI OUT.
4.3. LOW CUT: When active, this lter cuts all frequencies below 120 Hz - ideal if you play an
instrument that generates aggressive low frequencies. It enables you to connect a subwoofer, and
prevent unwanted vibration and possible damage to your DAVID X.
4.4. MASTER: Controls the overall system volume.
4.5. POWER LED: Indicates when the amplier is switched ON.
4.6. LINE OUT: This unbalanced jack socket enables connection to external systems. The output
volume depends on the regulation of the MASTER control.
4.7. MUTE: This cuts the audio on the Master.
4.8. INSERT: This stereo jack socket enables the connection of an external device (compressor,
equalizer, etc.) in series to all the outputs.
4.9. REVERB Master: This control regulates the general level of the digital reverb, common to
all channels. The amount of effect can be individually regulated for each single channel via the
dedicated controls.
4.1 4.2 4.3 4.4
4.5
4.6
4.7
4.8
4.9
3.1

9
Class–A High Voltage Preamp / No Integrated Circuits / No NFB
SWISS
MADE
1 3
INSTRUMENT IN STEREO IN
2
10V GAIN WARM LOW MID HIGH REV VOLUME
MASTERDI OUT
GAIN RESON LOW MID HIGH REV VOLUME
flat
INSERT REVERB
master
LINE OUT
DAVID X
GND LIFT
INSTRUMENT INMIC IN P24 10V
DAVID X 1 2 0 W A T T
A C O U S TIC
A M PLI F I E R
SER IAL NUMBER
WWW . S C H E R T L E R . C O M
M
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+
S
W
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8 0 W A T T P O W E R C O N S U M P TIO NX S E R I E S
CAUTION
RISK OF ELECTRIC
SHOCK
DO NOT OPEN
TO REDUCE RISK OF FIRE,
DO NOT EXPOSE THIS
EQUIPMENT TO RAIN
OR MOISTURE. FOR
CONTINUED PROTECTION
AGAINST RISK OF FIRE,
REPLACE ONLY WITH THE
SAME TYPE AND RATING
OF FUSE.
240 Hz
150 Hz
5.1
5.2
5.3
REAR PANEL
5.1. POWER ON/OFF: System ON/OFF switch.
5.2. GROUND LIFT: This switch connects and disconnects the ground.
5.3. MAINS POWER CONNECTION:
Connection to mains Fuse carrier
220 - 230 V~ 50 Hz / 60 Hz T 1.6 A L 250 V
240 V~ 50 Hz T 1.6 A L 250 V
120 V~ 60 Hz T 3.15 A L 250 V
100 V~ 50 Hz / 60 Hz T 3.15 A L 250 V
PLEASE ENSURE THAT THE CORRECT VOLTAGE IS OBSERVED
AND THE ORIGINAL CONNECTION CABLE IS USED

ACOUSTIC XAMPS
SIGNAL FLOW
WARM
3B EQ.
REVERB
MASTER
GAIN
TO DI OUT
TO LINE OUT
TO AMP
PHANTOM
P24
XLR
JACK
10V
INSERT
RESON
3B EQ.
GAIN
JACK
+
STEREO IN
LOW CUT
OL OL
10V