Revel LFO - Manual (Page 2)

2 LFO Programming Software
User Guide
ABOUT THIS DOCUMENT
Your Revel subwoofer contains an ultra high-quality DSP-based signal processor that can maximize the subwoofer's low-frequency performance (and in
a 2.x-channel music system, the performance of the main left and right speakers). The subwoofer’s DSP processor offers sophisticated user-confi gurable
crossover functions, multi-band parametric equalization (EQ), and individual speaker delay and polarity settings, all of which are confi gurable with your
computer via the downloadable Revel LFO (Low-Frequency Optimizer) software (LFO software).
This Revel LFO Software User Guide is a comprehensive guide to the installation and use of the Revel LFO software. This guide also details the
recommended audio measurement equipment and procedures you will use in the optimization process, how to load the test results into the Revel LFO
software, and how make equalization adjustments to your system. Before attempting to use the Revel LFO software you should thoroughly and completely
read this user guide.
The fi rst part of this document provides instructions for optimizing the performance of subwoofers being used in a multi-channel surround-sound system.
The second part provides instructions for optimizing the performance of subwoofers being used in a two-channel audio system.
To enjoy the maximum performance that your Revel subwoofer can deliver, fi rst read and perform the setup instructions found in the quick-start guide
that was included with it, particularly the placement recommendations. (For reference, the placement recommendations are repeated directly below, and
the Ultima Rhythm2 and Performa3 B112/B110 quick-start guides are repeated in their entirety in the Appendix section at the end of this document). You
should also read the instructions found in the owner’s manuals of the associated components in your audio system.
SYSTEM OPTIMIZATION BY YOUR REVEL DEALER
If the kind of precise audio tuning described in this guide is not something you want to undertake, we recommend that you talk with your authorized Revel
dealer about having them professionally calibrate your system. If you wish to optimize your system yourself read on for detailed instructions.
BEFORE YOU BEGIN
Before using the Revel LFO software, review the following placement information to ensure that your subwoofer(s) are optimally located in your listening
room; download and install the LFO software in your computer and connect your computer to your Revel subwoofer.
SUBWOOFER PLACEMENT CONSIDERATIONS
When using subwoofers within the limited confi nes of a typical home theater or listening room, the refl ections, standing waves and absorptions generated
within the room will create peaks and dips in the bass response that can vary greatly depending on where the listeners are located in the room – a listener
seated in one location may hear an overabundance of bass created by a response peak at that location, while another listener only a few feet away may
hear a considerable lack of bass created by a response dip at that location.
The subwoofers’ locations within the room (along with the room’s dimensions) also have a profound effect on the creation of these bass response
peaks and dips. Careful subwoofer placement alone cannot compensate for all bass response peaks and dips throughout a room, but careful subwoofer
placement can eliminate or signifi cantly reduce the largest response dips.
It is very important to reduce response dips throughout the room as much as possible via proper subwoofer placement because equalization cannot be
used to compensate for large response dips. For example, using equalization to attempt to restore a 13dB response dip requires that the subwoofer
amplifi er delivers twenty times the power at that frequency. This can quickly overdrive the subwoofer amplifi er into clipping, which will signifi cantly
degrade audio quality and reduce the system's overall dynamic range.
In almost any room, placing the subwoofers in corners will produce the fewest large bass response dips and will also produce the most large bass
response peaks. With the subwoofers so placed, you can then use the Revel LFO software’s sophisticated room equalization capability to compensate for
the response peaks, resulting in superb bass performance.
How Many Subwoofers Do I Need?
Revel strongly recommends that you install multiple subwoofers regardless of your room’s size. Even after using the LFO software’s room equalization
to remove the response peaks, installing a single subwoofer will result in the least consistent bass performance throughout the room. Using multiple
subwoofers can cancel some room modes at the various listening locations, resulting in much more consistent low-frequency sound quality throughout
the listening area. Additionally, it is often impossible to locate a single subwoofer such that large response dips, which cannot usually be corrected
via equalization, are not present. The use of two or more properly placed subwoofers can almost always eliminate or signifi cantly reduce such dips in
response.