Lehle SUNDAY DRIVER SW II User manual

OPERATING INSTRUCTIONS
LEHLE SUNDAY DRIVER SW II

LEHLE GmbH · Germany · www.lehle.com · [e-mail]
Dear Musician!
Thank you for purchasing the LEHLE
SUNDAY DRIVER SW II!
I have been building units that switch,
split and route signals with no technical
compromises and with maximum musical
fidelity since 1999.
Your new LEHLE SUNDAY DRIVER SW II
comprises only the very best components.
Every assembly of your LEHLE SUNDAY
DRIVER SW II has been made and tested
in Germany.
Your LEHLE SUNDAY DRIVER SW II is of
extremely robust design and construc-
tion, to make sure that you get absolutely
years and years of enjoyment from it. If
you should nonetheless have a problem,
or simply a question, just mail me or a
member of the Lehle team at:
[e-mail]
I wish you the very greatest pleasure and
success using your LEHLE SUNDAY DRIV-
ER SW II!

LEHLE GmbH · Germany · www.lehle.com · [e-mail]
CONTENT
Introduction
Technical data
General description
Typical uses of the LEHLE SUNDAY DRIVER SW II live as a
line driver
cable driver (unbalanced and balanced)
booster
DI box with preamp
Typical uses of the LEHLE SUNDAY DRIVER SW II in the studio as
recording preamp
recording preamp with LEHLE P-SPLIT III
signal flow diagram
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LEHLE GmbH · Germany · www.lehle.com · [e-mail]
The LEHLE SUNDAY DRIVER SW II is a
compact high-end preamp for all types
of electric and acoustic instruments - a
preamp for electric and acoustic guitars
and basses, not to mention other stringed
instruments (such as violins, cellos and
double basses) to realize their full musical
potential.
The switchable version expands on the
classic LEHLE SUNDAY DRIVER II with a
soft-touch foot switch, to activate and de-
activate the pedal.
The LEHLE-Switch works with a micro-
controller and an intelligent True-Bypass-
Relay-Circuit with active pop suppression
circuit, thereby allowing the LEHLE SUN-
DAY DRIVER SW II to switch even faster
than mechanical switches, noise-free and
without wear.
The easy-action mushroom-shaped but-
ton characteristic of LEHLE products is
mounted in the cover, so that your foot
pressure is transmitted indirectly, via a
spring. Thus the electronics board is not
exposed to mechanical loads, making the
LEHLE SUNDAY DRIVER SW II virtually in-
destructible and guaranteeing years of
trouble-free switching.
When ON, its circuit is based on a dis-
crete Class A circuit with JFET technology
and provides two modes of operation,
selected by a mode selector switch with
gold-plated contacts:
„D“ stands for Driver: in this mode, your
guitar signal is amplified, with absolutely
no modification, at the input impedance
of a guitar amp, eciently eliminating
losses on the route through leads and ef-
fects; the signal remains strong and clear,
retaining its full dynamics.
The second setting „S“ - as in Sunday -
multiplies the input impedance by five,
bringing out previously inaudible details
and, as gain increases, giving your guitar
a characteristic and unmistakable warmth
that has given this preamp its name - the
result is a sound as mellow as a sunny
Sunday afternoon.
Even at the maximum +18 dB gain set-
ting, the LEHLE SUNDAY DRIVER II al-
ways stays clean and absolutely free of
background noise, thanks to its studio-
standard overall dynamic range of 130
dB. To exploit the dynamics of tube am-
plifiers to the full, the input voltage is also
INTRODUCTION

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LEHLE GmbH · Germany · www.lehle.com · [e-mail]
rectified from the power supply socket,
then filtered, stabilized and transformed
to 30 V.
When OFF, the LEHLE SUNDAY DRIVER
SW II provides two dierent modes of
operation: in TB (= True Bypass) mode,
the input and output are linked via relay,
with zero tonal loss. True-Bypass mode is
the best option if you have a small setup
with short cable routings and for when a
treble booster or old-school fuzz pedal is
placed after the LEHLE SUNDAY DRIVER
SW II.
If you have long cables or a complex ef-
fects board configuration, switch to TS (=
True Sound) mode, and the LEHLE SUN-
DAY DRIVER SW II is active as a buer,
without amplifying or modifying the sig-
nal in any way. In this mode, the LEHLE
SUNDAY DRIVER SW II operates as a
totally neutral line-driver equivalent to
mode D with the gain pot turned all the
way to the left.
The Bypass mode option enables you to
eortlessly and tone-fully integrate the
LEHLE SUNDAY DRIVER SW II into any
setup, no matter how complex.
And not just on Sundays!
We take care of your signal so that you
can take care of the music.

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LEHLE GmbH · Germany · www.lehle.com · [e-mail]
TECHNICAL DATA
Weight 350 g
-110 dBu (20 Hz - 20 kHz)
+22 dBu
3.55“
0.008 % (0 dBu, 1 kHz)
3.8“
20 Hz – 100 kHz
1.85“
1 MΩ
9-15 V DC
5 MΩ
165 m A
220 Ω
+20 dBu
18 dB
Length
Max. Ausgangspegel
Width
Level noise floor
Overall height
Total harmonic distortion
Supply voltage
Frequency range
Current consumption
Input impedance D-mode
Output impedance
Max input level
Input impedance S-mode
Max gain

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LEHLE GmbH · Germany · www.lehle.com · [e-mail]
GENERAL DESCRIPTION
MADE IN GERMANY
SUNDAY DRIVER
SD
/
TB
TS /
1. INPUT SOCKET
Connect your instrument to this socket.
The LEHLE SUNDAY DRIVER SW II pro-
cesses signals from electric and acoustic
stringed instruments, such as electric gui-
tars and basses, western guitars, classi-
cal guitars and all kinds of stringed in-
struments. This compact preamp has no
trouble balancing out low signal levels,
and eliminating sound losses caused by
long cables and treble pickups.
2. S/D-SELECTOR SWITCH
Use this switch to select the mode you
want.
This gold-plated contact switch enables
you to change between the two sound
modes.
Mode D for ”Driver” (switcher pressed)
selects neutral amplification, and the in-
coming signal is amplified at the input im-
pedance of a guitar amp, 1 MOhm, ef-
ficiently eliminating sound losses caused
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LEHLE GmbH · Germany · www.lehle.com · [e-mail]
by long cables and/or multiple eects.
The signal remains strong and clear, and
retains its dynamics.
In mode S for ”Sunday” (switcher not
pressed), the input impedance is multi-
plied by five, to 5 MOhm, making pre-
viously unheard details suddenly audible
whilst imparting an unmistakable and
characteristic warmth to the sound when
the gain knob is turned up.
3. TS/TB-SELECTOR SWITCH
Use this switch to select the bypass mode
you want.
In OFF status, the LEHLE SUNDAY DRIV-
ER SW II provides two dierent modes of
operation.
In TB for “True-Bypass” mode, the input
and output are linked with zero losses
to one another via an intelligent True-
Bypass-Relay-Circuit with active pop sup-
pression circuit.
True-Bypass mode (switch pressed) is the
best option for a small setup with short
cable routings and for when a treble
booster or a classic fuzz pedal is looped
in after the LEHLE SUNDAY DRIVER SW
II.
The line driver function, located at the
start of the signal or in an eects chain,
is the better solution for long cables and
for complex eects board configurations.
Switch the LEHLE SUNDAY DRIVER SW II
to TS for “True Sound” mode, and it is
active as a buer, without amplifying or
modifying the signal in any way.
In this mode, the LEHLE SUNDAY DRIVER
SW II operates as a totally neutral line
driver – equivalent to Mode D with the
gain pot turned all the way to the left.
4. OUTPUT SOCKET
Connect your target device here.
For instance, an amplifier, a mixer panel,
a stage box or a sound card.
The output can be tapped unbalanced
(TS jack) or balanced (TRS jack).
To tap the output balanced, the LEHLE
SUNDAY DRIVER SW II has to be either
activated (LED blue) or the TS/TB-selec-
tor switch (3) set to “True Sound”.
5. EXTERNAL POWER SUPPLY
Connect a power supply with a voltage
of 9 – 15 V.
In order for the LEHLE SUNDAY DRIVER
SW II to work flawlessly, it needs a current
supply.
This should supply a minimum of 9 V and
a maximum of 15 V. Polarity is of no im-
portance. The input voltage is rectified
from the power supply socket, then fil-
tered, stabilized and transformed to 30 V
which guarantees maximum headroom.
In order to avoid noise it‘s recommend-
able to use a single power supply or an
TS TB

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LEHLE GmbH · Germany · www.lehle.com · [e-mail]
output of a multi power supply oering
galvanically isolated outputs for the LEH-
LE SUNDAY DRIVER SW II.
6. LED
If the LED is showing blue, the gain con-
troller and S/D-selector switch are active.
The high-intensity LEDs under the lenses
clearly indicate the switching-state, even
under stage lighting.
If the LED is showing white, the LEHLE
SUNDAY DRIVER SW II is in bypass and
depending on the position of the TS/TB-
selector switch (3) in “True-Bypass” or
“ Tr u e S oun d ”.
7. GAIN CONTROLLER
Use the gain controller to adjust the in-
tensity of the preamp from a slight level
up to a powerful boost.
The gain control knob consists of black
anodized aluminium and is recessed into
the housing. It can be easily turned by
placing your fingertip in the top depres-
sion, and thanks to the recessed design,
your setting cannot be inadvertently dis-
turbed on stage or during transportation.
The LEHLE SUNDAY DRIVER SW II with its
discrete Class A JFET circuitry performs
two functions simultaneously - reducing
signal impedance on the one hand, and
boosting the signal on the other.
THE LEHLE SUNDAY DRIVER SW II AS
AN IMPEDANCE CONVERTER:
When the gain controller is at the left-
hand stop (in the ”0” or ”seven o’clock”
position), it operates purely as an imped-
ance converter.
With the knob in this position, you can
compensate for sound losses that can oc-
cur when long cables or multiple eects
are used.
THE LEHLE SUNDAY DRIVER SW II AS A
BOOSTER:
A buer starts to amplify the signal when
the gain controller is turned further in the
clockwise direction.
Tube amplifiers, preamps and distortion
pedals can thus be driven slightly beyond
the limit. Since the frequency response of
tubes especially are not linear, the LEHLE
SUNDAY DRIVER SW II ensures that the
resultant overdrive distortion sounds har-
monious and amplifies less treble in ”S”
mode as the “Boost” rises.
The result can range from a pleasant
sound with no shrillness, up to a silky
warm, harmonious overdrive distortion
on tube amplifiers.
8. TRUE-BYPASS SWITCH
Use this switch to select between the orig-
inal and the boosted signal.
The LEHLE SUNDAY DRIVER SW II
switches all audio signals controlled by
a microcontroller and an intelligent True-

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LEHLE GmbH · Germany · www.lehle.com · [e-mail]
Bypass-Relay-Circuit with an active pop
suppression function.
Triggered by the easy-action mushroom-
shaped button characteristic of LEHLE
products mounted in the cover so that
your foot pressure is transmitted indirectly
via a spring. Thus the circuit board is not
exposed to mechanical loads, making the
LEHLE SUNDAY DRIVER SW II virtually in-
destructible and guaranteeing years of
trouble-free switching. In OFF status, the
LEHLE SUNDAY DRIVER SW II provides
two dierent modes of operation, TB for
“True-Bypass” and TS for “True Sound”
mode. In ON state, the LED (6) shows
blue, the gain controller is active and you
can choose between the sound modes D
for “Driver” and S for “Sunday”.
9. BASE AND FIXING
If required, mount the LEHLE SUNDAY
DRIVER SW II to a pedalboard using the
mounting kit.
The LEHLE SUNDAY DRIVER SW II can be
mounted to a plate such as a pedalboard
using the two holes in the bottom of the
pedal.
You can find the optional LEHLE Mount-
ing Kit V3 (order number 100981) online
at www.lehle-components.com.
To mount, undo the four housing screws
by using a 2.5 mm Allen key and detach
the cover.
Then fix the device base to a base plate
using the two screws, the washers and the
spacers of the Mounting Kit.
Attach the cover and tighten the four
housing screws - done!
For flexible solutions we recommend us-
ing 3M Dual Lock™ instead of Velcro for
stability, which you can also find in handy
sizes at www.lehle-components.com
If you are using the Velcro / Dual Lock™
method, please make a note of the serial
number on the bottom of the pedal be-
fore you cover it, in case you have a sup-
port question for us later and don‘t fancy
dismantling your board!