Alesis ModFX User manual

Reference Manual

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Copyright 2002, Alesis. All rights reserved
Reproduction in whole or in part is prohibited.
Specifications subject to change without notice.
All trademarks are the property of their respective holders.
7-51-0119-A
8/2002

Table of Contents
1
Introduction....................................................................3
Welcome! .........................................................................................................3
About the Philtre ...........................................................................4
Important features of your Philtre..............................................................4
Philtre Key Features ......................................................................................5
How to Use This Manual.............................................................6
Safety Instructions/Notices .....................................7
Important Safety Instructions (English)............................7
CE Declaration Of Conformity................................................9
FCC Compliance Statement......................................................9
Instructions de Sécurité Importantes (French).........................................10
Lesen Sie bitte die folgende Sicherheitshinweise
(German) ..................................................................................................12
Quick Start Guide ........................................................15
If you can’t wait to get started......................................................................15
Hook it up to a synthesizer...........................................................................15
A quick overview of the controls ...........................................16
Rear Panel........................................................................................................16
Connections ....................................................................17
Unpacking and Inspection............................................................................17
Installing in a Rack .........................................................................................17
Power................................................................................................................17
Connecting to the Channel Inserts of a mixing console: ........................19
Connecting to the Main Outputs of a mixing console: ...........................20
Connecting to the Aux Send/Return of a mixing console: ....................21
Connecting to the inserts on an instrument amplifier:............................22
Connecting to equipment with XLR inputs and outputs:.......................23
About audio cables.........................................................................................23
Using the ModLink........................................................................24
Using the Philtre ..........................................................25
What is filtering?............................................................................25
Filter curves, orders, and slopes ..................................................................26
Modulating the filter frequency...................................................................26
What is Tempo Sync? ....................................................................................27
To turn Tempo Sync off:..............................................................................27
Description of Controls...............................................................28
Rate ...................................................................................................................28
Depth................................................................................................................29
Phreeq...............................................................................................................29
Regen................................................................................................................30
TYPE Rocker Switch.....................................................................................36
Steep..................................................................................................................38
Reset Mod........................................................................................................38
Tap Tempo......................................................................................................39
Bypass...............................................................................................................40
Using the Foot Switch...................................................................................40
Sample Settings.............................................................41
Blank Settings Templates..............................................................................44
Troubleshooting............................................................45

Table Of Contents
2
Troubleshooting Index................................................................45
Avoiding ground loop noise.........................................................................47
Line conditioners and spike protectors ......................................................48
Care and Maintenance ................................................................49
Cleaning............................................................................................................49
Refer all servicing to Alesis...........................................................................49
Obtaining repair service ................................................................................50
Specifications.................................................................51
Audio Input.....................................................................................................51
Audio Output..................................................................................................51
Audio Performance........................................................................................51
Mechanical.......................................................................................................51
Index...................................................................................53
Warranty/Contact Alesis ...........................................54
Alesis Limited Warranty................................................................................54
Alesis Contact Information ..........................................................................55

Introduction
3
Welcome!
Thank you for making the Alesis Philtre a part of your studio.
Since 1984, we've been designing and building creative tools for
the audio community. We believe in our products, because we've
heard the results that creative people like you have achieved with
them. One of Alesis' goals is to make high-quality studio
equipment available to everyone, and this Reference Manual is an
important part of that. After all, there's no point in making
equipment with all kinds of capabilities if no one explains how to
use them. So, we try to write our manuals as carefully as we build
our products.
The goal of this manual is to get you the information you need as
quickly as possible, with a minimum of hassle. We hope we've
achieved that. If not, please drop us an email and give us your
suggestions on how we could improve future editions of this
manual.
We hope your investment will bring you many years of creative
enjoyment and help you achieve your goals.
Sincerely,
The people of Alesis
F
or more effective
service and product
update notices, please
register your Philtre
online at:
www.alesis.com/
support/
warranty.htm

Introduction
4
About the Philtre
Your new Philtre is a member of the Alesis ModFX family of
performance effects boxes. This particular ModFX unit is a filter
effect with modulation.
Each ModFX unit provides a different set of sound effects and
signal processing, and they are easy to arrange and connect to each
other. With a uniform, friendly, uncomplicated user interface and
high-resolution digital processing, the ModFX product line is
perfect for keyboardists, guitarists, and any other studio or live
performance artists.
Important features of your Philtre
High Resolution Processing
The Philtre internally uses 28-bit stereo digital signal processing.
The digital-to-analog and analog-to-digital conversion is sampled
at 48kHz with 24 bits of resolution. That means you can get the
effect you want, without adding unwanted noise and distortion.
ModLink
If you’re using multiple ModFX boxes to make your own unique
effects chain, ModLink makes it easy to hook up without needing
patch cords between units in the chain. The nine-pin connectors
built into each side of the case enable a ModFX box to transfer
digital audio and word clock directly to another. Any number of
units can be connected together.
Configurable Modulation
The Philtre features configurable modulation. The user can
control the shape, rate, and depth of the modulation, and it can be
triggered by the audio input itself. The rate of modulation can be
synchronized to the tempo, both by tap tempo and by audio input.

Introduction
5
Philtre Key Features
•Four different filter types, with steep slope switch and
adjustable regeneration
•Five different modulation sources, including Trigger and
Envelope for note-by-note filter sweeping
•Tempo synchronization keeps filter effect in time with the
music
•Tap Tempo makes it easy to set the speed of modulation by
tapping a beat on the top panel
•Uniform, friendly, uncomplicated user interface—no fiddling
with complicated menus or “hidden” knobs
•Reset Mod lets you reset the phase of any modulation shape
from its beginning
•Stereo processing via four 1/4” unbalanced connectors
•ModLink port, a cable-free connection that transfers digital
audio and word clock to other boxes in the ModFX family
•Footswitch connection to control the bypass function
•Ability to mount 3 ModFX boxes in the optional ModFX
rack adapter
•Input trim control to adjust input level
•Internal 28-bit digital processing
•24-bit D/A and A/D conversion at 48kHz sampling rate for
quiet, distortion-free effects
•External 9VAC power supply included

Introduction
6
How to Use This Manual
A little technical knowledge will help you get the most out of your
gear...it’s really pretty simple. This manual is divided into the
following sections describing the various functions and
applications for the Philtre. While it's a good idea to read through
the entire manual once carefully, those having general knowledge
about effect devices should use the table of contents to look up
specific functions.
Chapter 1: Quick Start. If you're already experienced with effect
boxes, this will get you started using the Philtre right away. It's a
short guide to the essential elements of hooking it up and using it
for the first time. A brief tour of the front and rear panels also
directs you to the chapters focused on individual features.
Chapter 2: Connections gives detailed instructions for connecting the
Philtre to a variety of typical audio systems. It also discusses the
process of linking the Philtre with other ModFX devices.
Chapter 3: Using the Philtre explains the controls of the Philtre and
their functions.
Chapter 4: Sample Settings provides a selection of sound charts
created by the sound designers at Alesis for you to try.
Near the end of the manual are troubleshooting tips,
specifications, and an index to help you find what you're looking
for.
H
elpful tips and advice are
highlighted in a shaded box
like this
When something important
appears in the manual, an
exclamation mark (like the
one shown at left) will appear
with some explanatory text.
This symbol indicates that
this information is vital when
operating the Philtre.

Safety Instructions/Notices
7
Important Safety Instructions (English)
Safety symbols used in this product
This symbol alerts the user that there are important
operating and maintenance instructions in the literature
accompanying this unit.
This symbol warns the user of uninsulated voltage within
the unit that can cause dangerous electric shocks.
This symbol warns the user that output connectors contain
voltages that can cause dangerous electrical shock.
Please follow these precautions when using
this product:
1. Read these instructions.
2. Keep these instructions.
3. Heed all warnings.
4. Follow all instructions.
5. Do not use this apparatus near water.
6. Clean only with a damp cloth. Do not spray any liquid cleaner
onto the faceplate, as this may damage the front panel
controls or cause a dangerous condition.
7. Install in accordance with the manufacturer's instructions.
8. Do not install near any heat sources such as radiators, heat
registers, stoves, or other apparatus (including amplifiers) that
produce heat.
9. Do not 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 or the
third prong are provided for your safety. When the provided
plug does not fit into your outlet, consult an electrician for
replacement of the obsolete outlet.
10. Protect the power cord from being walked on or pinched,
particularly at plugs, convenience receptacles, and the point
where they exit from the apparatus.
Continued next page

Important Safety Instructions
8
11. Use only attachments or accessories specified by the
manufacturer.
12. Use only with a cart, stand, bracket, or table designed for use
with professional audio or music equipment. In any
installation, make sure that injury or damage will not result
from cables pulling on the apparatus and its mounting. If a
cart is used, use caution when moving the cart/apparatus
combination to avoid injury from tip-over.
13. Unplug this apparatus during lightning storms or when unused
for long periods of time.
14. Refer all servicing to qualified service personnel. Servicing is
required when the apparatus has been damaged in any way,
such as when the power-supply cord or plug is damaged, liquid
has been spilled or objects have fallen into the apparatus, the
apparatus has been exposed to rain or moisture, does not
operate normally, or has been dropped.
15. This unit produces heat when operated normally. Operate in a
well-ventilated area with at least six inches of clearance from
peripheral equipment.
16. This product, in combination with an amplifier and
headphones or speakers, may be capable of producing sound
levels that could cause permanent hearing loss. Do not
operate for a long period of time at a high volume level or at a
level that is uncomfortable. If you experience any hearing loss
or ringing in the ears, you should consult an audiologist.
17. Do not expose the apparatus to dripping or splashing. Do not
place objects filled with liquids (flower vases, soft drink cans,
coffee cups) on the apparatus.
18. WARNING: To reduce the risk of fire or electric shock, do
not expose this apparatus to rain or moisture.

Important Safety Instructions
9
CE Declaration Of Conformity
See our website at:
http://www.alesis.com
FCC Compliance Statement
This device complies with Part 15 of the FCC rules. Operation is
subject to the following two conditions: (1) This device may not
cause harmful interference and (2) this device must accept any
interference received, including interference that may cause
undesired operation.
NOTE: This equipment has been tested and found to comply
with the limits for a Class B digital device, pursuant to Part 15 of
the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference in a residential installation.
This equipment generates, uses and can radiate radio frequency
energy and, if not installed and used in accordance with the
instructions, may cause harmful interference to radio
communications. However, there is no guarantee that interference
will not occur in a particular installation. If this equipment does
cause harmful interference to radio or television reception, which
can be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more of
the following measures:
•Reorient or relocate the receiving antenna.
•Increase the separation between the equipment and receiver.
•Connect the equipment into an outlet on a circuit different
from that to which the receiver is connected.
•Consult the dealer or an experienced radio/TV technician for
help.

Important Safety Instructions
10
Instructions de Sécurité Importantes (French)
Symboles utilisés dans ce produit
Ce symbole alèrte l’utilisateur qu’il existe des instructions
de fonctionnement et de maintenance dans la documentation
jointe avec ce produit.
Ce symbole avertit l’utilisateur de la présence d’une
tension non isolée à l’intérieur de l’appareil pouvant engendrer des
chocs électriques.
Ce symbole prévient l'utilisateur de la présence de tensions
sur les raccordements de sorties, représentant un risque
d'électrocution.
Veuillez suivre ces précautions lors de
l’utilisation de l’appareil:
1. Lisez ces instructions.
2. Gardez ces instructions.
3. Tenez compte de tous les avertissements.
4. Suivez toutes les instructions.
5. N’utilisez pas cet allareil à proximité de l’eau.
6. Ne nettoyez qu’avec un chiffon humide. Il est potentiellement
dangereux d'utiliser des pulvérisateurs ou nettoyants liquides
sur cet appareil.
7. Installez selon les recommandations du constructeur.
8. Ne pas installer à proximilé de sources de chaleur comme
radiateurs, cuisinière ou autre appareils (don’t les
amplificateurs) produisant de la chaleur.
9. Ne pas enlever la prise de terre du cordon secteur. Une prise
murale avec terre deux broches et une troisièrme reliée à la
terre. Cette dernière est présente pour votre sécurité. Si le
cordon secteur ne rentre pas dans la prise de courant,
demandez à un électricien qualifié de remplacer la prise.
10. Evitez de marcher sur le cordon secteur ou de le pincer, en
particulier au niveau de la prise, et aux endroits où il sor de
l’appareil.
Suite de la page suivante

Important Safety Instructions
11
11. N’utilisez que des accessoires spécifiés par le constructeur.
12. N’utilisez qu’avec un stand, ou table conçus pour l’utilisation
d’audio professionnel ou instruments de musique. Dans toute
installation, veillez de ne rien endommager à cause de câbles
qui tirent sur des appareils et leur support.
13. Débranchez l’appareil lors d’un orage ou lorsqu’il n’est pas
utilisé pendant longtemps.
14. Faites réparer par un personnel qualifié. Une réparation est
nécessaire lorsque l’appareil a été endommagé de quelque sorte
que ce soit, par exemple losrque le cordon secteur ou la prise
sont endommagés, si du liquide a coulé ou des objets se sont
introduits dans l’appareil, si celui-ci a été exposé à la pluie ou à
l’humidité, ne fonctionne pas normalement ou est tombé.
15. Puisque son fonctionement normale génère de la chaleur,
placez cet appareil au moins 15cm. des équipments
péripheriques et assurez que l’emplacement permet la
circulation de l’air.
16. Ce produit, utilisé avec un amplificateur et un casque ou des
enceintes, est capable de produite des niveaux sonores
pouvant engendrer une perte permanente de l’ouïe. Ne
l’utilisez pas pendant longtemps à un niveau sonore élevé ou à
un niveau non confortable. Si vous remarquez une perte de
l’ouïe ou un bourdonnement dans les oreilles, consultez un
spécialiste.
17. N'exposez pas l'appareil à l'égoutture ou à l'éclaboussement.
Ne placez pas les objets remplis de liquides (vases à fleur,
boîtes de boisson non alcoolique, tasses de café) sur l'appareil.
18. AVERTISSEMENT: Pour réduire le risque du feu ou de
décharge électrique, n'exposez pas cet appareil à la pluie ou à
l'humidité.

Important Safety Instructions
12
Lesen Sie bitte die folgende Sicherheitshinweise (German)
Sicherheit Symbole verwendet in diesem
Produkt
Dieses Symbol alarmiert den Benutzer, daß es wichtige
Funktionieren und Wartung Anweisungen in der Literatur gibt, die
diese Maßeinheit begleitet.
Dieses Symbol warnt den Benutzer der nicht isolierten
Spannung innerhalb der Maßeinheit, die gefährliche elektrische
Schläge verursachen kann.
Dieses Symbol warnt den Benutzer, dem Ausgabestecker
Spannungen enthalten, die gefährlichen elektrischen Schlag
verursachen können.
Folgen Sie bitte diesen Vorkehrungen, wenn
dieses Produkt verwendet wird:
1. Lesen Sie die Hinweise.
2. Halten Sie sich an die Anleitung.
3. Beachten Sie alle Warnungen.
4. Beachten Sie alle Hinweise.
5. Bringen Sie das Gerät nie mit Wasser in Berührung.
6. Verwenden Sie zur Reinigung nur ein weiches Tuch.
Verwenden Sie keine flüssigen Reinigungsmittel. Dies kann
gefährliche Folgen haben.
7. Halten Sie sich beim Aufbau des Gerätes an die Angaben des
Herstellers.
8. Stellen Sie das Gerät nich in der Nähe von Heizkörpern,
Heizungsklappen oder anderen Wärmequellen (einschließlich
Verstärkern) auf.
9. Verfehlen Sie nicht den Zweck des grounging Terminals auf
dem Netzstecker. Dieses Terminal wird für Ihre Sicherheit zur
Verfügung gestellt.
10. Verlegen Sie das Netzkabel des Gerätes niemals so, daß man
darüber stolpern kann oder daß es gequetscht wird.
Fortsetzung auf nächster Seite

Important Safety Instructions
13
11. Benutzen Sie nur das vom Hersteller empfohlene Zubehör.
12. Verwenden Sie ausschließlich Wagen, Ständer, oder Tische, die
speziell für professionelle Audio- und Musikinstrumente
geeignet sind. Achten Sie immer darauf, daß die jeweiligen
Geräte sicher installiert sind, um Schäden und Verletzungen zu
vermeiden. Wenn Sie einen Rollwagen benutzen, achten Sie
darauf, das dieser nicht umkippt, um Verletzungen
auszuschließen.
13. Ziehen Sie während eines Gewitters oder wenn Sie das Gerät
über einen längeren Zeitraum nicht benutzen den Netzstecher
aus der Steckdose.
14. Die Wartung sollte nur durch qualifiziertes Fachpersonal
erfolgen. Die Wartung wird notwendig, wenn das Gerät
beschädigt wurde oder aber das Stromkabel oder der Stecker,
Gegenstände oder Flüssigkeit in das Gerät gelangt sind, das
Gerät dem Regen oder Feuchtigkeit ausgesetzt war und
deshalb nicht mehr normal arbeitet oder heruntergefallen ist.
15. Dieses Gerät produziert auch im normalen Betrieb Wärme.
Achten Sie deshalb auf ausreichende Lüftung mit mindestens
15 cm Abstand von anderen Geräten.
16. Dieses Produkt kann in Verbindung mit einem Verstärker und
Kopfhörern oder Lautsprechern Lautstärkepegel erzeugen, die
anhaltende Gehörschäden verursachen. Betreiben Sie es nicht
über längere Zeit mit hoher Lautstärke oder einem Pegel, der
Ihnen unangenehm is. Wenn Sie ein Nachlassen des Gehörs
oder ein Klingeln in den Ohren feststellen, sollten Sie einen
Ohrenarzt aufsuchen.
17. Setzen Sie den Apparat nicht Bratenfett oder dem Spritzen
aus. Plazieren Sie die Nachrichten, die mit Flüssigkeiten
(gefüllt werden Blumevases, Getränkdosen, Kaffeetassen)
nicht auf den Apparat.
18. WARNING: um die Gefahr des Feuers oder des elektrischen
Schlages zu verringern, setzen Sie diesen Apparat nicht Regen
oder Feuchtigkeit aus.

Important Safety Instructions
14
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1Quick Start Guide
15
If you can’t wait to get started
The Alesis Philtre is a unique product, but its basic hookup and
operation is similar to other effects units in most respects. If
you're experienced with signal processors, this chapter is a
"shorthand" guide for those who want to start using the Philtre
right away. If you have questions about any of the features, don’t
worry – later chapters will unveil the mysteries of the Philtre's
special features.
Hook it up to a synthesizer
1. First, make sure the power is off to all the components
you’re connecting to: amp, mixer, and instruments.
2. Pull the Philtre and its power supply out of the package.
3. Using a pair of 1/4” instrument cables, plug the outputs
of the synthesizer into the INPUTS on the back of the
Philtre.
4. Connect the OUTPUTS of the Philtre to the inputs of a
mixer, powered speakers, or instrument amplifier.
5. Insert the power jack of the Philtre’s power adapter into
the POWER 9VAC input on the rear panel of the
Philtre and plug the power adapter into an AC outlet
(preferably on a power strip with its switch off).
The Philtre doesn’t have a POWER switch of its own. The
moment you plug in the power, its top panel LEDs will come on.
6. Turn the power on to the system: the keyboard, then
the Philtre’s power strip (if it’s not already on), then the
mixer, then the amp.
7. Turn the INPUT TRIM knob on the back of the Philtre
while playing the keyboard to adjust the input level. The
SIGNAL LED on the top panel will light green, not red,
when the level is correct.
8. Experiment with the knob and button settings on the
Philtre to create different sounds.
For more detailed information on connecting the Philtre, see
chapter 2: Connections.
I
f you're new to signal
p
rocessing...
start with the more detailed
instructions for hookup and
operation starting in the next
cha
p
ter.

1Quick Start Guide
16
A quick overview of the controls
TYPE
The TYPE switch selects the
kind of filter as shown by the
LEDs next to the switch. See
page 36.
REGEN
(regeneration)
This increases
gain at the
filter corner for
a sharper filter
peak. In Band
modes it also
sets the width
of the band.
PHREEQ
Determines the
frequency
center or
corner of the filter.
Rear Panel
Plug the power adapter in
here.
The ModLink connectors let
you arrange several ModFX
units in a chain, without
having to use input and
output cables inside the
chain.
STEEP
This increases the slope of the
chosen filter curves.
Reset Mod
Retarts the modulation from
the beginning of its cycle.
Generates a trigger in
TRIGGE RED mode, or
changes the pattern in
PATTERN mode.
BYPASS lets signal pass
through without any filtering.
The FOOT SWITCH may be
connected to any momentary
pedal, to engage the BYPASS
function.
INPUTS and OUTPUTS are
standard 1/4” line-level
jacks. Plug single-channel
device s i n to the
LEFT/MONO input.
TAP TEMPO
Active in TEMPO SYNC
mode only. Tap a regular
beat on this button, and the
mod speed of the Philtre will
be set at some multiple of that
beat, as set by the RATE
knobs.
MODULATION
SELECT switch selects
the type of wave used to
modulate the filter
frequency.
The RATE
knob affects
the modulation
speed, in
cooperation
with the
TEMPO SYNC
and TAP
TEMPO
buttons. See
page39.
DEPTH
controls the
depth of the
modulation.
SIGNAL LED
When this lights green, the
Philtre is getting an input
signal. When it’s red, it’s
seeing too much level, so turn
down the instrument ...
...or the TRIM control here
on the back panel.
If you’re using a ModLink
chain, you only need to
connect to the first unit’s
input, and the last unit’s
output.

2Connections
17
Unpacking and Inspection
Your Philtre was packed carefully at the factory. The shipping
carton was designed to protect the unit during shipping. Please
retain this container in the highly unlikely event that you need to
return the Philtre for servicing.
The shipping carton should contain the following items:
•Philtre with the same serial number as shown on the
shipping carton
•Power Adapter
•This instruction manual
To register your purchase, go to the Alesis website at
www.alesis.com.
Installing in a Rack
The Philtre is designed for tabletop use, but can also be installed
in a standard 19" audio equipment rack. For rack mounting,
contact your Alesis dealer for the ModFX Rack. This rack shelf
holds three ModFX units in a 3-space high 19” rack.
Power
The Philtre comes with an AC power adapter that transforms
the voltage from a standard outlet into 9 volts AC (830 mA).
Plug the small end of the power adapter cord into the Philtre’s
POWER 9VAC socket and then plug the adapter itself into a good
quality, noise-free AC power source of the proper rating.
The supplied AC line adapter is designed only for the destination
to which the unit is shipped. To use the Philtre in another
country, contact your Alesis dealer for a P3 adapter suitable for
the electrical system in the country you are traveling to.
M
ake sure you read the
initial Important Safety
I
n s t r u c t i o n s c h a p t e r a t t h e
f
ront of this manual.
A
void “popping”:
D
on’t plug the power adapter
into the Philtre until all other
audio cables have been
hooked up. Make sure your
amplifier or pow e r e d
speakers are switched off
when plugging in the Philtre
to avoid damage.

2Connections
18
Connecting audio
The Philtre will work in many different applications, whether you
are connecting an instrument directly into it, or connecting it
through a mixing console. But since the Philtre is a stereo
effect unit, it’s important to know whether the source will be
stereo or mono.
Mono In, Mono or Stereo Out
If you’re connecting a guitar or bass directly to the Philtre, hook it
up this way:
1. Connect a 1/4" phone cord to the [LEFT/MONO] INPUT
of the Philtre from a mono source. (The Left input will then
feed both inputs of the effect.)
2. Connect another 1/4" phone cord from the LEFT OUTPUT
of the Philtre to an amplification system or mixer input.
3. If the amp or mixer is stereo, connect a second 1/4" phone
cord from the RIGHT OUTPUT of the Philtre to the other
input of the stereo amplification system, or the next mixer
input.
4. If you’re connecting directly to a stereo mixer, pan the two
channels hard left and hard right to get the maximum effect.
When connecting audio
cables and/or turning power
on and off, make sure that all
devices in your system are
turned off and the volume
controls are turned down.
Turn up the trim...
M
ost guitars and basses have
relatively low output levels.
F
or the quietest effect, turn
up the volume on the guitar to
f
ull, then crank up the
[TRIM] control on the back
of the Philtre until the
SIGNAL LED on its top panel
f
lashes red while you play,
then back it off a bit.