Suhr Alexa User manual

User Guide

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Table of Contents
Overview � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �3
Powering Alexa � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �4
Getting Connected (Mono) � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �4
Getting Connected (Stereo)� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �5
Selecting Buffer Bypass / True Bypass � � � � � � � � � � � � � � � � � � � � � � � � � � � � �6
Channel Selection / Bypass� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �7
Controls � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �8
Waveforms � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �9
Selecting Expression Control / Tap Tempo � � � � � � � � � � � � � � � � � � � � � � � � � 10
Using an Expression Pedal with Alexa � � � � � � � � � � � � � � � � � � � � � � � � � � � � 11
Using Tap Tempo with Alexa � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �12
3-Position Slide Switch � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �12
FX Link (External Control) � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �13
Sample Settings � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �14
Technical Specications � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �15
Warranty � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �15

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Overview
The Suhr Alexa is a two channel, analog stereo chorus with digital control.
Utiilizing bucket brigade technology, classic chorus tones are achieved with
the extra flexibility of new waveforms, tap tempo and expression speed con-
trol.
Each channel contains six unique waveforms that allow you to tailor your
modulation to suite your needs. The triangle and sine waveforms are clas-
sic waveforms used in a majority of choruses, however there are two new
custom waveforms, the rotary and photo cell waveforms that allow the Al-
exa to achieve swirling rotary sounds or pulsing vibe-like sounds. With the
final ramp up and ramp down waveforms, rhythmic chorus tones can be
achieved that give a delay-like effect on sustained notes.
Each channel contains an individual Speed, Depth, Delay and Waveform
option. Channel A contains a switch that allows for Vibrato as well. Wether
you want to have a chorus that can switch from slow lush chorus to a fast
rotary chorus with a hit of a botton, or use it like no chorus has been used
before with the ramp waveforms, Alexa can cover a large range of analog
chorus tones and more.
Thank you for purchasing the Suhr Alexa Analog Chorus Pedal.
Please take the time to read this manual to get the most out of the pedal.
The more you familiarize yourself with the features of this pedal, the more
you will enjoy its benets and maximize its potential.

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Powering Alexa
DC Input: Alexa powers with a 9Vdc regulated, center-negative power
supply that can supply 100mA or more, such as a BOSS PSA power
supply.
Exp / Tap
1
Getting Connected (Mono)
OUTPUTS
L(MONO)
R
FX LINK
INPUT
ON
FL
OFF
1 2
Input: Plug the cable from your guitar into here, or from the previous
effect’s output.
Output: Plug a cable from here to an amp or another effect’s input.

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Getting Connected (Stereo)
Input: Plug the cable from your guitar into here, or from the previous
effect’s output.
Output Right: Plug a cable from here to the right amplifier (or another
effect’s input) for the right channel of the chorus.
Output Left: Plug a cable from here to the left amplifier (or another
effect’s input) for the left channel of the chorus.
BUF / TRU-BYP switch: Located on the inside of the pedal are two
slide switches. The right switch determines if the pedal is in buffered or
true bypass mode. Switch to buffer bypass (BUF) for stereo operation.
Restart the pedal by powering it off and back on to finish setting it in
buffer bypass mode.
WARNING: The true bypass feature is dedicated for the left output only. When
using Alexa in stereo, please set the pedal to buffer bypass, which is located
on a switch on the inside of the pedal. When turning the effect off in true by-
pass, the Right channel is disconnected from the input. Buffer Bypass mode
sends a buffered signal through both outputs, and is the mode that should be
used for stereo scenarios. Alexa is shipped in buffer bypass mode.
OUTPUTS
L(MONO)
R
FX LINK
INPUT
ON
FL
OFF
1 32

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Selecting Buffer Bypass / True Bypass
When turning off the pedal, the outputs can receive a buffered signal (buffer
bypass) of the input, or the left mono output can receive a non-buffered signal
(true bypass) of the input. An internal slide switch determines whether Alexa
uses buffer bypass (labeled BUF) or true bypass (labeled TRU-BYP).
Important: Switching from one mode to another requires the pedal to be
powered off and re-powered to take effect.

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Channel Selection / Bypass
Alexa has two channels (green and red) with independent settings that are
selected by the switch labeld A/B [2]. The channels can be set for the same
sound on each channel with slight modifications, or they can be radically dif-
ferent.
The left side is Channel 1 and is indicated by a green LED above the A/B
footswitch [2].
The right side is Channel 2 and is indicated a red LED above the A/B footswitch
[2].
A / BOn/Off
VibratoChorus
Depth BDelay BDepth ADelay A
Speed B
Speed A
1 2
Stepping on the A/B footswitch will toggle between channels A and B.
When the LED is green, Channel 1’s settings are used.
When the LED is red, Channel 2’s settings are used.
Stepping on the ON/OFF footswitch to bypasses the effect.
NOTE: If the internal bypass switch on the inside of the pedal is switched
to BUF, both left and right outputs get a buffered input signal. If the in-
ternal bypass switch is switch to TRU-BYP (MONO ONLY), an unbuff-
ered input signal will pass through the left output only.
Channel Selection
Bypass

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Controls
Waveform Selector: Chooses one of the 6 waveform shapes that will modu-
late the Vibrato / Chorus. A more indepth description of each waveform is on
page 9.
Speed: Adjusts the speed at which the modulation occurs. Turning the knob
clockwise sets the speed to up to 10Hz. Turning the knob counter clockwise
sets the speed down to 1/2Hz.
Delay: Adjusts the delay point that chorus modulates around. This ranges
from 10ms to 40ms.
Tip: Increasing the Delay typically gives a “wider” sound. If the chorus’s pitch
wobbles too dramatically, counteract by decreasing the Depth control to keep
a smoother chorus sound.
Depth: The depth knob reduces (counter clockwise) or boosts (clockwise)
the amount of modulation.
Chorus / Vibrato: This switch is only active on channel A. This allows you to
turn Channel A into a vibrato effect (pitch bending).
A / BOn/Off
VibratoChorus
Depth BDelay BDepth ADelay A
Speed B
Speed A

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Waveforms
Alexa contains six musical waveforms to choose from when dialing in a cho-
rus/vibrato setting.
A / BOn/Off
VibratoChorus
Depth BDelay BDepth ADelay A
Speed B
Speed A
Triangle: A classic waveform used in a majority of analog choruses.
Results in a smooth modulation. Good for a smooth lush chorus with
less noticeable pitch bending.
Sinewave: Another common waveform used on choruses. Sinewave
modulation can give a throb sound, and is a great waveform for Vibra-
to, as the pitch bends evenly.
Rotary: This waveform is a custom shape used to emulate the swirling
sound of a rotary speaker. It is similar to the Triangle shape in smooth-
ness.
Photocell: This waveform emulates the photocell throb effect found
on some modulation effects that use a light dependent component to
control the modulation. It has a pulsing assymetrical shape and sound.
Ramp Down: This waveform ramps the modulation downward and re-
peats, which results in a rhythmic effect that is delay-like on sustained
notes.
Ramp Up: This waveform modulates in an upward direction then re-
peats, which results in a rhythmic effect.

10
Selecting Expression Control / Tap Tempo
Alexa’s chorus speed can be controlled via an Expression pedal in Ex-
pression mode, or a Momentary Switch in Tap Tempo mode through
the 1/4” TRS jack located on the right side of the pedal.
The function of the EXP / TAP jack is determined by an internal slide
switch. When set to (TAP), the jack takes a mono cable to a momen-
tary switch. When set to (EXP), the jack takes a stereo cable to an ex-
pression pedal. When changing modes, the pedal must be powered off
before taking effect.
Exp / Tap
1