O Audio BASH User manual

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 1 of 12
Copyright © 2008
O Audio 300W BASH
®
Subwoofer
Amplifier
User’s Manual

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 2 of 12
Copyright © 2008
TABLE OF CONTENTS
INTRODUCTION...............................................................................................................3
WARNINGS AND CAUTIONS ............................................................................................4
INSTALLATION.................................................................................................................5
CONTROL DESCRIPTION..................................................................................................9
SERVICE AND WARRANTY .............................................................................................10
SPECIFICATIONS ...........................................................................................................11

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 3 of 12
Copyright © 2008
INTRODUCTION:
Thanks for purchasing the O Audio 300W BASH
®
Subwoofer Amplifier. This amplifier
features BASH
®
technology which enables a high output power amplifier in a small
package.
Traditional Class AB amplifiers use a fixed voltage power supply. This approach is
wasteful and necessitates extensive heatsinking, particularly for high power
amplifiers such as this one. Additionally, primitive unregulated power supplies are
typically used that require a substantial, and expensive, transformer to assure
stable supply voltages over a range of load conditions. Inexpensive subwoofer plate
amplifiers typically skimp on the transformer size in the interest of low cost.
BASH
®
amplifier technology marries a robust Class AB amplifier with a smart power
supply that adaptively provides the necessary output voltage required to produce
low-distortion output power. The O Audio 300W BASH
®
Subwoofer Amplifier will
produce up to 300W RMS into a 4Ùload at a Total Harmonic Distortion (THD) of less
than 0.09% and less then 0.04% between 0W –275W. With an 8Ùload, the
amplifier will produce up to 150W RMS at a THD less than 0.05%. Soft limiting
circuitry is active above 150W (into an 8Ùload).
In addition to BASH
®
amplifier technology, the O Audio 300W BASH
®
Subwoofer
Amplifier includes the essential continuously variable controls (output level, phase,
and crossover frequency) necessary to integrate a subwoofer into your listening
environment.

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 4 of 12
Copyright © 2008
WARNINGS AND CAUTIONS:
WARNING –THIS AMPLIFIER MODULE IS DESIGNED FOR INSTALLATION INTO A
SUBWOOFER ENCLOSURE, OR INTO ITS OWN ENCLOSURE. WHEN PROPERLY
INSTALLED, ONLY THE EXTERIOR FACEPLATE SHOULD BE ACCESSIBLE TO THE USER –
ANY OTHER CONFIGURATION IS NOT SAFE FOR THE CASUAL USER. IT IS IMPORTANT
THAT THIS MODULE BE PROPERLY HOUSED TO PREVENT ACCIDENTAL CONTACT WITH
DANGEROUS VOLTAGES –BOTH MAINS AC (115VAC OR 230VAC) AS WELL AS HIGH
VOLTAGE DC (>42VDC). THESE VOLTAGES CAN INJURE AND KILL AND SHOULD BE
TREATED WITH RESPECT.
WARNING –AS WITH ANY PIECE OF ENTERTAINMENT ELECTRONICS, THIS MODULE IS
INTENDED FOR INDOOR USE. IT SHOULD NOT BE EXPOSED TO WATER (INCLUDING
CONDENSATION).
CAUTION – Damage not covered by the warranty can occur if the AC SELECT switch
setting does not match the actual AC input voltage.
CAUTION –The amplifier relies on convection cooling, so air must pass freely over
the faceplate. Do not mount the amplifier in a location where faceplate airflow is
blocked. The amplifier does include overtemperature protection and will shut down
if overheated. This thermal protection will automatically reset once the amplifier is
cool.
CAUTION –This amplifier is designed for use with drivers that are rated at 4Ùor
greater. Drivers whose nominal impedance rating is less than 4Ùcan damage the
amplifier. Driver combinations (this includes any configuration where there are
multiple voice coils) that result in a load of less than 4Ù(when calculated using the
driver’s nominal impedance) can damage the amplifier. Damage caused by low
impedance loads are not covered by the warranty.

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 5 of 12
Copyright © 2008
INSTALLATION:
The O Audio 300W BASH
®
Subwoofer Amplifier is designed to be installed into a
subwoofer enclosure or its own dedicated enclosure. Switches and other orifices are
airtight. Also, the back of the faceplate has a gasket to provide an airtight seal when
the amplifier module is mounted into a subwoofer enclosure.
All dimensions are in inches unless otherwise noted.

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 6 of 12
Copyright © 2008
INSTALLATION (continued):
Side view:

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 7 of 12
Copyright © 2008
INSTALLATION (continued):
Cutout dimensions are 6.0”H x 9.875”W. We recommend allowing a minimum
mounting depth of 3.5”.
Electrical connections to the subwoofer amplifier consist of the AC mains input,
audio input (either low or high level), and speaker output.
CAUTION – Damage not covered by the warranty can occur if the AC SELECT switch
setting does not match the actual AC input voltage. Also, the AC input fuse must be
sized per the fuse recommendations printed on the faceplate.
The amplifier is designed to operate on either 115VAC/60Hz or 230VAC/50-60Hz AC
input. The amplifier is shipped in the North American configuration (AC input switch
setting and AC fuse selection are set for 120VAC/60Hz).
To change the AC input range, start by disconnecting AC power from the amplifier.
DO NOT CHANGE AC INPUT RANGE WITH THE AC POWER CONNECTED TO THE
AMPLIFIER! Set the AC Select switch to the desired range (115VAC or 230VAC). ALSO,
THE AC INPUT FUSE MUST BE PROPERLY SELECTED TO MATCH THE AC INPUT RANGE!
Please refer to the faceplate silkscreen for the correct fuse size and rating. The
fuseholder is integrated into the AC inlet connector housing and is located just
below the AC inlet connector.
AC mains connections are simply made with the provided AC cable. One end of the
provided cable (IEC320 style receptacle) plugs into the connector located on the
amplifier faceplate –the other end, into a 15A or 20A three-pronged North American
AC receptacle. Due to the wide variety of plugs outside of North America, we are
unable to stock and offer power cables suitable for other regions.
Should the AC inlet fuse blow, REMOVE AC POWER FROM THE UNIT; then, determine
and clear the source of the problem (such as shorted speaker output). With AC
power removed, replace the blown fuse. THE AC INPUT FUSE MUST BE PROPERLY
SELECTED TO MATCH THE AC INPUT RANGE! Please refer to the faceplate silkscreen
for the correct fuse size and rating. Replacing the fuse with a value other than that
shown on the faceplate silkscreen will void the warranty.

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 8 of 12
Copyright © 2008
Use only one set of audio inputs –either the low level audio inputs (RCA receptacles)
or the high level audio inputs (binding posts).
Low level audio inputs are made via RCA receptacles. The amplifier can accept left
and right channel signals. Single channel connection (such as an LFE output from a
home theater receiver or pre-pro) may be made to either input.
High level audio inputs are made via binding posts. The amplifier can accept
speaker level right and left channel signals.
In the final installation location, please assure that air can flow freely over the
faceplate.
Speaker connections are made using the pre-attached cable. Connect the red wire
to the + terminal on the driver; the black wire to the –terminal on the driver.
DO NOT CONNECT THE AMPLIFIER TO DRIVERS OR DRIVER COMBINATIONS THAT ARE
LESS THAN 4Ù(BASED ON THE DRIVER NOMINAL RATING). Refer to the last Caution
on page 3 for more information.

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 9 of 12
Copyright © 2008
CONTROL DESCRIPTION:
Here is a list of controls with a brief description of function. Controls are listed in
order of appearance on the amplifier starting with the upper left:
VOLUME –This control is used to set the gain of the amplifier to match the
subwoofer’s output with the rest of your system.
PHASE –This control is used as necessary so the subwoofer does not sound “out of
step”with the rest of your system.
AUTO/ON –When set to the AUTO mode, the unit senses the input signal and
automatically turns on. This action is indicated by the LED (located to the left of the
GAIN knob) turning green. Once the unit does not sense any input signal, then the
unit enters standby mode after 10-20 minutes. This mode is indicated by LED turning
red.
CROSSOVER FREQUENCY –The built-in crossover is a 4
th
order (24dB/octave)
lowpass crossover which may be adjusted from 40Hz to 110Hz. Refer to Chart 2 in
the Specification section for more information.
CROSSOVER BYPASS SWITCH –The built-in crossover can be bypassed by setting
this switch to DISABLED. Refer to Chart 1 in the Specification section for amplifier
frequency response when the crossover is bypassed.
POWER –Primary AC power control. Works in conjunction with the AUTO/ON switch
(see AUTO/ON switch description earlier in this section).
AC SELECT –Selects the AC input mode –either 115VAC/60Hz or 230VAC/50-60Hz.
The AC input fuse (see faceplate silkscreen for values) must match the selected
range. WARNING –DAMAGE NOT COVERED BY THE WARRANTY CAN OCCUR IF THE AC
SELECT SWITCH SETTING DOES NOT MATCH THE ACTUAL AC INPUT VOLTAGE.

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 10 of 12
Copyright © 2008
SERVICE AND WARRANTY:
O Audio warrants the O Audio 300W BASH
®
Subwoofer Amplifier from material or
workmanship defects for a period of one year after purchase. We will provide a
replacement (either new or refurbished, at our discretion) with a full one-year
warranty. Please retain proof of purchase date. This warranty does not cover
damage that results from misuse of this product.
O Audio provides attentive customer service. We want you to be happy with this
product. Please e-mail us at [e-mail] should you have any
questions or comments regarding this product.

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 11 of 12
Copyright © 2008
SPECIFICATIONS (subject to change/correction without notification) :
Audio
Output Power 300W RMS (into 4Ùload @ 0.09% THD)
0W-275W RMS (into 4Ùload @ <0.04% THD)
150W RMS (into 8Ùload @ <0.05% THD)
Frequency Response
Chart 1 –Frequency Response Showing Range of Crossover Settings

O Audio 300W BASH
®
Subwoofer Amplifier User’s Manual V1.2 page 12 of 12
Copyright © 2008
SPECIFICATIONS (subject to change/correction without notification) :
Audio (continued)
Minimum Load Impedance 4Ù(based on nominal driver rating)
Signal to Noise Ratio 105dB
Phase Control 0° to 180°
Crossover Range 40Hz to 110Hz
Crossover Topology 4
th
order (24dB/octave)
AC Power
AC Input Voltage and Frequency 115VAC/60Hz or 230VAC/50-60Hz
(switch selectable)
Max Input Power 400W
Environmental
Ambient Temperature (Operating) 10°C to 40°C
Humidity up to 90% non-condensing
Operating Temp Altitude Derating 2°C per 1,000ft