Radial Engineering BT-PRO User manual

www.radialeng.com
True to the Music™
®
User Guide
BT-PRO™
Bluetooth®Direct Box
Radial Engineering Ltd.
1588 Kebet Way, Port Coquitlam
British Columbia, Canada, V3C 5M5
Tel: [phone] • Fax: [phone]
Email: [email protected]

Table of Contents Page
Features .......................................................................................1
Overview.......................................................................................2
Making Connections................................................................. 3-4
Bluetooth Pairing ..........................................................................5
Testing and Using.........................................................................6
Block Diagram ..............................................................................7
Specications ...............................................................................8
Warranty .......................................................................Back cover
Congratulations on your purchase of the Radial BT-Pro™!
The BT-Pro is a high-resolution, stereo direct box designed to
wirelessly pair with Bluetooth® enabled devices and seamlessly
transfer the streaming audio to a pair of balanced audio outputs.
This makes it ideal for connecting a laptop, cell phone or tablet to
a mixing console, powered speakers or PA system.
This manual covers the setup and operation of the BT-Pro in
various applications. Please take a few minutes to read it through
in order to familiarize yourself with the BT-Pro features so you
can get the most out of them. If you have any questions that are
not covered in this manual, please consult the FAQ section on
our website. This is also where we post the latest updates. If you
still do not nd what you are looking for, feel free to send us an
email at [email protected] and we will do out very best to reply
in short order.
Radial®BT-Pro™ User Guide

Radial Engineering Ltd. BT-Pro™ Bluetooth DI
True to the Music
®
1
FEATURES
1 2 3 4 5 6 7
1. LEVEL: Used to set the overall output level.
2. MONO: Sums the stereo signal to mono. When active, the LED
indicator illuminates. Mono mode reduces the channel count on
the PA or lets you send the signal to two separate audio systems
simultaneously.
3. HEADPHONE: Mini 3.5mm stereo (1/8”) TRS headphone output is
used to check the output from the source for trouble shooting. Works
with ear buds and standard headphones.
4. POWER INPUT/USB: Used to power the BT-Pro. Connect the
included USB Mini-B cable to a computer or wall power supply. This
is a power input only that will not pass audio or other data.
5. XLR OUT: Standard XLR male outputs follow AES format with pin-1
(ground), pin-2 (+), pin-3 (-).
6. GROUND LIFT: Used to help eliminate hum and buzz caused by
ground loops. Lifts pin-1 on both XLR outputs.
7. RIGHT-ISO/LEFT-ISO: Switches on side panel let you insert
transformer isolation when needed on each channel. Use to
eliminate hum and buzz caused by ground loops.
8. COVER: Blue Sintra®cover protects the internal antenna while
allowing the wireless signal to pass through without interference.
9. LED PAIRING INDICATORS: Red
and blue LED’s toggle back and
forth during pairing to provide visual
feedback of the wireless Bluetooth
connection status.
10. RESET/ON: Recessed switch on
side panel used to reset the BT-Pro
for pairing with another device.
8 9 10

True to the Music
®
Radial Engineering Ltd. BT-Pro™ Bluetooth DI
2
OVERVIEW
A typical direct box is a device that lets you interface an unbalanced (hi-
Z) audio output with a professional balanced (low-Z) input as found on a
PA or recording system. The Radial BT-Pro is similar in that it pairs with
a Bluetooth enabled device and converts the streamed digital signal to
analog balanced stereo output.
The BT-Pro’s antenna rst picks up the streaming audio and converts
it to analog audio. A level control allows you to adjust the output level
and a mono sum switch can be activated to send the mono signal to two
separate audio systems or used to check for phase issues. The 3.5mm
mini-headphone output can be used to monitor the stereo signal and test
for audio prior to connecting to the PA. Before the XLR output, isolation
transformers may be switched into the circuit to eliminate noise caused
by ground loops. The signal is then balanced to drive long cables without
noise.
A front-panel level control is used to adjust the output volume along with
the volume setting for the headphones. This is variable from a mic level
output to feed a traditional mixing channel preamp input to a line level
to feed the line input on a mixing console, recording system or powered
speaker. The BT-Pro ensures the digital signal is delivered to the PA as
faithfully as possible.
The BT-Pro is easy to setup and use. Once it is powered up and the ON
switch is engaged, it will automatically appear as an available device on
your Bluetooth enabled computer, tablet or smart phone.

Radial Engineering Ltd. BT-Pro™ Bluetooth DI
True to the Music
®
3
MAKING CONNECTIONS
Before making any connections, always ensure your audio system is either
turned down or turned off in order to protect more sensitive components
from damage caused by loud turn-on or plug-in transients. The BT-Pro
uses a USB Mini-B connector and cable for its power requirements. Use
the included ‘Mini-B to TYPE A’ USB cable and connect to a computer,
USB hub or the included USB wall charger. You may also use any
standard USB wall charger that is included with most phones and tablets,
as the BT-Pro will only draw a small amount of current.
To block DC current, activate the
transformer isolation by switching
the LEFT-ISO and RIGHT-ISO to
the ‘right’ position.
IMPORTANT NOTE: Although the BT-Pro is equipped with protective
transformers that may be inserted into the signal path to protect it from
48V DC, you should turn the phantom power off on your console as it
is not needed. If only a global phantom power switch is present, then
make sure the transformers are inserted!
TYPE A USB
Fits most laptops and computers
OFFON
BE SURE THAT THE BT-PRO IS TURNED OFF BEFORE CONNECTING
THE POWER CABLE to avoid initial intermittent power spikes to the
electronics.
TYPE Mini-B USB
Used to connect to the BT-Pro

True to the Music
®
Radial Engineering Ltd. BT-Pro™ Bluetooth DI
4
Connecting the BT-Pro to your audio system is done using two XLR
cables. This follows the AES standard with pin-1 (ground), pin-2 (+), and
pin-3 (-). These XLRs can be connected to mic or line level inputs.
Left
Right
Once you make the connections, turn up the audio system. It is good
practice to always test at a low volume. Listen for noise; if present,
try lifting the ground or inserting the transformers using the miniature
switches on the side panel. The transformers will introduce isolation and
block DC which will help reduce all types of noise.
Headphone output
It is important to note that there is a very loud headphone output built-into
the BT-Pro that enables professional grade, low sensitivity headphones
to be used. Make sure you always set the level completely off (fully
counter-clockwise) before using. Adjusting the level control on the BT-
Pro will affect both the XLR and headphone output. The headphone amp
is not actually intended for listening – it is for testing to ensure the signal
is being processed by the BT-Pro and being properly output by the DAC
(digital to analog converter). If you do not hear sound in the PA, this lets
you know that the problem is likely not the BT-Pro but maybe another
connection or that a piece of equipment needs to be checked.
Audio connections for PA system and recording systems
use balanced XLR cables up to 100 meters (300’).
Headphone Safety Warning
Caution: Very Loud Amplier
See specications page for details

Radial Engineering Ltd. BT-Pro™ Bluetooth DI
True to the Music
®
5
BLUETOOTH PAIRING
Once the BT-Pro is connected to a power supply, a blue LED on the
top of the unit will illuminate. At this point you can turn the RESET/
ON switch to the ON position, and the BT-Pro will be available to pair
with Bluetooth devices. Check the available devices on your Bluetooth
enabled playback source; the BT-Pro should appear in the list as ‘Radial
Eng’. Once you select the BT-Pro, your plackback device should prompt
you for a password. The password is 1246. Once initially paired, the BT-
Pro automatically converts the streaming audio to analog for connection
to a variety of systems. Your device should automatically reconnect on
future sessions, as your smartphone does in your car.
1. Make sure the BT-Pro volume control is
turned fully counter clockwise.
2. Enable Bluetooth pairing on your
Bluetooth enabled device.
3. Connect your BT-Pro to power, a blue
LED on the top of the unit will indicate
that it is receiving power.
4. Turn on the BT-Pro to enable Bluetooth
pairing.
5. Blue and red LED’s will alternate
showing the BT-Pro is in search mode
for pairing.
6. Your Bluetooth device will identify the
BT-Pro as ‘Radial Eng’ in the Bluetooth
devices menu.
7. Select the BT-Pro in your Bluetooth
devices menu.
8. Your Bluetooth device will then ask for
a rst time password for the BT-Pro.
Type in: 1246.
9. Once your Bluetooth device has paired
with the BT-Pro, the blue LED will ash
once every three seconds. When audio
is playing, the blue LED will ash three
times quickly every three seconds.
Once your Bluetooth device has been paired to the BT-Pro, the BT-Pro
will automatically pair to the same Bluetooth device when the BT-Pro is
turned back on in range.

True to the Music
®
Radial Engineering Ltd. BT-Pro™ Bluetooth DI
6
TESTING AND USING
First, set the BT-Pro’s LEVEL control to the 7 o’clock (off) position. This
will allow you to adjust the output level on the y. Next, check the status
of the MONO SUM switch and LED indicator. For stereo, set the switch to
the outward position (LED off). For dual mono operation, set the switch to
the inward position (LED on).
It’s a good idea to start testing the Bluetooth audio with a sound le you
are familiar with. Set your source’s output level and the level of the media
playback software (if applicable) at 80% or higher for optimal signal to
noise. A higher volume from the source will allow the BT-Pro to operate
at the lowest noise oor. Keep in mind that various media les will play
back at different volume levels depending on your software and how the
sound le was recorded.
Slowly raise the output level of the BT-Pro. It is good practice to always
test at a low volume to ensure proper connections have been made and
all devices in the signal chain are set up correctly and working. This way,
should a device not be turned on or a connection not fully made, it will
not create a loud transient ‘pop’ in the PA that could damage a tweeter or
annoy your audience. When satised, slowly increase the input gain on
your mixing console until you reach an appropriate level.
Going out of range
If your Bluetooth device goes out of the range of your BT-Pro (greater
than 12 meters), the device playback will pause and the blue LED on
the BT-Pro will slowly blink to show the unit is in ‘Stand-by’ mode. Once
the device is back in range, the BT-Pro will automatically reconnect
to continue playing back audio from your Bluetooth device. Stand-by
mode will not allow another Bluetooth device to pair with the BT-Pro. If
your Bluetooth device goes out of range from the BT-Pro for more than
two minutes, or if you want to connect a different Bluetooth device for
playback, you will need to reset the BT-Pro. This is done by turning the
RESET/ON switch off and back to on.
The BT-Pro allows for reception distances of up to 12 meters (40’),
which can be signicantly extended under ideal conditions. Should you
experience interference or signal dropouts, ensure that there is a clear
line of sight between the BT-Pro and your Bluetooth device. You can also
adjust the angle and placement of the BT-Pro, as this may also affect the
reception.
NOTE: If you’re using a computer with a USB Bluetooth dongle, some
pairing features may not be automatically available. Please refer to
your dongle’s software manual for instructions on how to activate
these features.

Radial Engineering Ltd. BT-Pro™ Bluetooth DI
True to the Music
®
BLOCK DIAGRAM*
7
* Subject to change without notice.
MONO
LEFT
RIGHT
OUTPUT
LEVEL
BLUE
RECEIVER
FILTER
FILTER
H/P
AMPLIFIER
TRANSFORMER FULL BYPASS SWITCHES
OUTPUT
OUTPUT
GROUND LIFT
HEADPHONE OUTPUT
PHASE
SPLITTER
/BUFFER
PHASE
SPLITTER
/BUFFER
TOOTH
CHASSIS_GND
L_OUT
R_OUT