Introduction
5
Introduction
Thank you for purchasing an Axe-Fx Ultra
TM
Pre-Amp / Effects Processor. You’re now the owner
of one of the most powerful musical instrument processors ever produced. By familiarizing yourself
with this manual you’ll be able to reap the full benefits of your unit. Please take a moment to read
through the sections that follow and acquaint yourself with the usage of your Axe-Fx Ultra
TM
.
What is the Axe-Fx?
What is the Axe-Fx? Well, let's start by telling you what it isn't.
It's not a modeler in the strict sense. Although it has cabinet emulation and different amplifier
"types" it does not attempt to model any amplifier or effect exactly. Rather the Axe-Fx was designed
to simply provide the effect as originally intended and with the utmost quality. All effects can be
described in terms of their desired sonic manipulation. All effect processors, whether "stomp boxes"
or otherwise, process the input signal to get an output signal, simple as that. However, some
processors obviously do better than others. The Axe-Fx approaches effects processing as a strict set
of specifications and implements those specifications.
For example, the wah effect in the Axe-Fx is not intended to model any of the classic wah-wahs.
Instead the input-output relationship of a wah was distilled into a set of specifications. From there
the effect was designed to exactly meet these specifications. There is no "black magic" or
obfuscation. The effect does exactly what it should do. Inherent in this approach is a degree of
flexibility that you do not get with other processors. In our wah example this allows you to set the
sweep range, "Q" and other parameters. Most modeling processors do not allow this level of control.
The Axe-Fx’s amp, drive and cabinet simulations, however, are very faithful reproductions of the
originals, but without the drawbacks of the originals. What this means is that they sound like the
originals but are easier to adjust and provide more flexibility and a wider range of tones. For
example, the Brownface amp sim sounds remarkably like a particular classic amp however the Axe-
Fx contains working midrange and presence controls. Also the tone controls are much more
responsive providing all the tones of the original plus new tones that the original could not achieve.
Once again the philosophy is practicality and presenting the “effect” as it was originally intended.
The Axe-Fx does not use any analog processing or any tubes. If you look inside
1
the Axe-Fx you
will not see any glowing tubes or any of the revered op-amps that the analog pundits claim offer
mystical sonic properties. What you will see are modern, high-quality components that offer
specifications and performance far exceeding any of the aforementioned devices.
The Axe-Fx does contain, however, very accurate digital replicas of actual vacuum tubes. We
gathered up some classic tubes and measured their transfer functions and then stored these transfer
functions in the Axe-Fx’s massive brain. Our replicas are so exact that we can reproduce the
harmonic spectrum of a real tube amp with amazing accuracy. Most modelers don’t even come
close.
1. Please do not open your Axe-Fx as damage may occur. Refer all servicing to qualified personnel.
