cabinet or an in-ear monitoring system the Booster must be activated
(LED lights blue). The basic sound is set up using the preamp/EQ section
of the Basswitch Clean Boost.
3. External power supply
Connect your external power supply here (9-15V; min. 60mA) with a
standard 5,5 x 2,1 mm connector.
Because of the uncompromising design, the quality of the components
and the switching technology used, the power consumption of the Bass-
witch Clean Boost is too high to run it satisfactorily on batteries. The exter-
nal power supply should provide not less than 9V and not more than 15V.
Either alternating (AC) or direct current (DC) sources can be used and the
polarity is not relevant. The voltage supplied is internally rectified, filtered,
stabilised and then brought to 18 V.
Note: To get the best out of your pedal set-up we recommend that
you use high quality power supplies with isolated output sections
in your set up!
Warning: The Lehle power supply (item no. 7014) with the connector
acc. to DIN 45323 is not suitable.
4. GAIN Control
Use this control to adjust the volume of your Clean Boost.
To permit optimal matching of signals this control enables you to boost
and to cut the signal, the neutral position is at 12 o’clock. The high-end
preamp of the Basswitch Clean Boost allows you to connect the Basswitch
Clean Boost directly to a power amp (see also point 2).
5. M (MID) Control
Use this control to adjust the amount of mids in your tone.
This control boosts and cuts the lower mids. The technical design used
enables a good sound to be maintained even when applying major adjust-
ments to the signal, but we suggest however to use this control with care,
the intention being more to subtly modify the sound than to fundamentally
change it.
6. B (Bass) Control
Use this control to adjust the amount of bass in your tone.
This control has been designed with the deepest frequencies of the bass
instruments in mind to permit a targeted cut and boost of these frequen-
cies. This control is very useful with passive basses, for instance, to give
them more depth and substance. The technical design used enables a
good sound to be maintained even when applying major adjustments to
the signal, but we suggest that you use this control with care to avoid a
bass-heavy sound.
7. T (Treble) Control
Use this control to adjust the amount of treble/presence in your tone.
This control enables you to create interesting sounds like the classic slap
sound (“Slappers delight”). Boosting the treble control brings life to dull
speaker cabinets and new life to old strings. When using new strings, es-
pecially new round-wound steel strings you can get the aggressive highs
under control by cutting the upper frequencies a little. It can also help, if
needed, to reduce the annoying rattling of the strings.
8. Footswitch
Push this switch to activate the booster.
Pressing the footswitch turns the Clean Boost on or into ‘straight through’
mode.
9. Status LED
This LED turns blue when the Clean Boost comes on and white in the
bypass-mode.
Tech Talk
True Bypass and True Sound
Today more and more effect pedals feature true bypass switching to com-
pletely bypass the pedal in the signal routing when the pedal is switched
off. The target of this design is to ensure that the pedal does not affect
the electrical signal when it is switched off. This way the sound is left
unaltered - in theory.
In practice, however, connecting several pedals featuring a true-bypass
design in series does not improve the sound or keep it unaltered at all.
Long runs of cable and multiple connections lead to a weak and lifeless
sound. On large pedalboards the overall length of the cable is enough for
the capacitance of the cable to have a negative effect on the sound. The
capacitance of the cable acts as a low-pass filter (= the low frequencies
pass through the filter while the high frequencies are filtered out). The
price and quality of the cable you are using will not change this physical
phenomenon.
A solution would be to use only devices with buffered bypass design in-
stead of true bypass. This, however, is only a good solution if the buffer is
of very high quality. If several units with buffered bypass are connected in
series it only needs one buffer to be noisy, to cut the dynamics of the sound
signal or to negatively affect the sound in any other way for the sound of
the whole effect chain to be spoilt. As the saying goes: “a chain is only as
strong as its weakest link”. In addition, the noise of the individual buffers
adds up to produce audible noise (It is a fact that every buffer produces
some noise, even if it cannot be heard when only a single buffer is used).
The ideal solution is to have a very high-quality buffer at the beginning
of the chain that brings the signal down to a very low impedance. This
makes the signal insensitive to the length of the cable. It is important,
however, that this buffer is of the highest quality with the dynamic range
and headroom necessary to ensure that all the details of the bass signal
stay are retained unaltered.
The effect pedals in the downstream should then ideally have true bypass
so that they will not have a negative effect on the now buffered signal,
as the true bypass design does not reduce dynamics and headroom or
produce any noise.
Conclusion: Having a True Sound Lehle buffer at the beginning of your
effect chain combined with good true-bypass-equipped effects in the loop
guarantees the best sound.
What is Lehle True Sound Technology?
Lehle True Sound Technology is a combination of several electrical design
measures with only one aim in view: to transmit the sound and the char-
acter of the instrument without altering it.
The voltage supplied to the Basswitch Clean Boost is internally rectified,
filtered and stabilized and then brought to almost 18 V. This gives enough
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