Ashdown Acoustic 100 - BK - Manual (Page 7)

7
Description
The AA-100 is a twin channel unit. Channel 1 is for
Active or Piezo inputs, while Channel 2 works for Low
Z or Microphone inputs on either jack or XLR.The two
channels allow both mic and pick-up inputs to be
mixed together to give the best possible sound for the
acoustic guitar. Alternatively one channel can be used
for the guitar and the other for a vocal mic to form a
mini PA system.
The ACOUSTIC CUBE has a single jack input for
connection to your instrument. This is a very high
impedance input in order to perfectly match the
output from Piezo pick ups that have no built in
preamplifier. These are the most common passive pick
up systems used in acoustic instruments. This input
should be sensitive enough for all current acoustic pick
up systems. It also has sufficient headroom to cope
with the output from those active (battery powered)
pick up/preamp systems built into many modern
instruments.
ACTIVE / PIEZO SWITCH
The Active / Piezo switch allows channel 1 input to be
set for active guitars (those with a built-in preamp) or
passive / piezo instruments where a higher input level
and impedance would be required.
PHANTOM POWER SWITCH (AA-100)
This can be switched in to apply a Phantom Power
voltage to channel 2 inputs. This is only for use with
suitable capacitor microphones. Do not switch this in
for any other type of input to channel 2.
INPUT LEVEL CONTROL / LED LEVEL INDICATOR
Once you have set your instrument to the required Eq
settings on both the amplifier and the instrument you
should then set the INPUT LEVEL to the most efficient
level to optimise signal to noise ratio. The optimum
level is when the input level LED is indicating GREEN
most of the time for normal playing, with occasional
peaks flashing RED. The LED indicates the level for
both units.
PHASE SWITCH IN / OUT
This switch reverses the Phase of the signal through
the amplifier and is used to help eliminate standing
wave feedback. As such it is very dependent upon
the position of the player relative to the amplifier. If
feedback is occurring.
SHAPE IN / OUT
This switch introduces a natural pre-shape to the
sound by adding a bass boost, a mid cut and a treble
boost that suits both strumming and finger picking
styles of playing.
BASS & TREBLE TONE CONTROLS
The BASS and TREBLE tone controls are ‘boost and
cut’ type controls with their FLAT setting being at the
centre position of the control. Turning the control in a
clockwise direction from its centre position increases
the bass or treble whilst turning it in an anticlockwise
direction will decrease the bass or treble.
NOTCH FILTER
The ACOUSTIC CUBE includes a NOTCH filter that
can be switched IN or OUT. This is an anti-feedback
device to allow amplification of an acoustic instrument
without trouble from feedback that is usually caused
by resonances from the body of the instrument.
A NOTCH filter removes a narrow band of frequencies
from the response of the amplifier. If this band of
frequencies is narrow enough it will not be missed
from the wide band of frequency response of the unit.
This narrow band or NOTCH is then made adjustable
so that it can be tuned to the resonant frequency
of the body of the instrument, thus reducing the
amplification at that particular frequency and
eliminating the feedback.
If feedback at a particular frequency becomes a
problem while playing then switch the NOTCH ‘IN’
and adjust the rotary control for the best position to
eliminate the feedback. If feedback is still a problem
then the only solutions is either move further away
from the amplifier or reduce the overall level of
volume you are using.
DIGITAL REVERB
The DIGITAL REVERB built into the ACOUSTIC CUBE
has a LEVEL control and two switches for selecting the
type and length of reverb.
Turning the LEVEL control clockwise adds reverb to
the signal and providing the GAIN control has been set
correctly there will be plenty of reverb available.
The switch on the left of the level control selects
the type of reverb. In its ‘up’ position PLATE reverb is
selected, this is a nice bright type of reverb with plenty
of presence in its sound quality. With the switch in its
‘down’ position ROOM reverb is selected which is a
mellower but rich, full type of reverb. Both of these
have been chosen as they are an ideal compliment to
acoustic instruments.
The switch on the right of the level control sets the
length of the selected type of reverb. In its ‘up’ position
it selects a long decay time and in its ‘down’ position a
short decay time.
VOLUME CONTROL
The VOLUME control is for setting the required output
stage volume from the amplifier.
POWER ON
A POWER ON LED. This will be illuminated when the
amplifier is receiving power from the Mains or external
power supply, is switched on and is ready to use.
Ashdown Amplifiers reserve the right to change specifications without notice. E & O E. All contents © Ashdown 2012.