BHI DSPKR User manual

DSPKR
10 Watt RMS Amplified DSP noise cancelling Speaker
User Manual
bhi Ltd
DSP noise cancellation products for radio and voice communications
1072-105D Iss B

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Important Information:
Copyright
This publication, including all photographs and illustrations is protected under international
copyright laws, with all rights reserved. Neither this manual, nor any of the material within,
may be copied or reproduced without the written consent of bhi Ltd.
Disclaimer
The information in this document is subject to change without notice. bhi Ltd makes no
representations or warranties with respect to the contents hereof and specifically disclaims
any implied warranties of merchantability or fitness for any particular purpose.
Furthermore, bhi Ltd reserves the right to revise this publication and to make changes from
time to time in the content hereof without obligation of bhi Ltd to notify any person of such
revision or changes.
Table of Contents
1. Packing List ……………………………………………………………………..page 3
2. Introduction……………………………………………………………………..page 3
3. Installation………………………………………………………………………..page 3
4. Operation…………………………………………………………………………page 4
5. Audio level setting……………………………………………………………..page 4
6. Noise cancellation………………………………………………………………page 4
6.1. Storing and un-storing of filter level…………………………………page 5
7. Sleep mode……………………………………………………………………….page 5
7.1. Waking up the unit…………………………………………………………page 5
7.2. Auto sleep function………………………………………………………..page 5
8. Specification…………………………………………………………………….page 5
9. Troubleshooting/FAQ’s…...…………………………………………………..page 6
10. bhi Support……………………………………………………………………..page 7

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DSPKR 10 Watt RMS Amplified DSP noise cancelling Speaker
1. Packing List - The DSPKR is shipped with the following:
•DSPKR noise cancelling speaker
•Integral black audio lead with 3.5mm mono plug attached.
•Speaker mounting bracket
•Fused DC power lead 1030-FPL (Red cable +ve, Black/red cable –ve)
•Mounting screws
•Operating manual & customer feedback card
2. Introduction
The bhi DSPKR amplified DSP noise cancelling speaker greatly improves the clarity and
intelligibility of speech in radio and voice communication systems. It is suitable for use in
many applications where high background noise and interference mean that you cannot
clearly hear what is being said. The speaker will enable the user to listen and concentrate
“stress-free”. Suitable applications where the speakers will be of great benefit are:
Amateur radio, CB radio, two-way radio, HF radio, marine communications, scanners, taxi
base stations and especially mobile installations. The speaker incorporates unique DSP
technology to remove unwanted background noise and interference from speech and has
up to 7 DSP filter levels allowing the user to optimise for their level of noise and
interference. The speaker simply connects into the extension speaker socket or
headphone socket of your audio equipment.
The DSPKR comprises a wide frequency range 4” speaker and an audio amplifier capable
of producing up to 10-Watts RMS audio power, with built in bhi DSP noise cancelling filter.
The unit requires an audio input signal of between 80 and 500mV level and a DC supply of
between 10 and 16 Volts (2A). The unit is supplied with an attached black 2 metre audio
cable with a moulded 3.5mm jack plug for the audio input, and a red/black 2.1mm fused
DC power lead with bare ends. A 3.5mm mono auxiliary output socket is provided to allow
the speaker to be used with headphones or to drive another loudspeaker. A 12V DC
power supply PSU12-1A is available as an optional extra (UK customers).
Note: The DSPKR is designed for speech signals and is not really suitable for music.
3. Installation
The speaker comes with a mounting bracket that enables the speaker to be used free-
standing on a desk or secured into vehicles using the self tapping screws provided.
When installing, ensure that adequate access can be gained to allow operation of the
Function button. Furthermore, when installing in vehicles, ensure that the unit is not in
direct sunlight or in a hot area.
Make sure that the DSPKR 3.5mm plug lead and the fused DC power lead are routed
away from sources of electronic interference or RF cables.
For best results try to use a separate power supply to power the speaker, and in a vehicle,
power directly from the vehicle battery as this will minimise the chance of alternator whine
and other electronic interference occurring.

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FUNCTION Button
A
UDIO level LED
4. Operation
Once installed and connected to the required audio source, apply power to both the audio
source and the speaker. When power is applied to the speaker, the indicators will step
through in sequence and the speaker will emit a low tone and the two high tones.
5. Audio Level setting
An AUDIO LEVEL LED indicates the input audio level that is being received from your
audio source. Once the correct level has been set on your audio source, the volume
control may be used to adjust the volume.
To set the audio level, turn your source volume control down to zero. Then gently
increase the volume until the AUDIO LEVEL LED lights. The optimum input level is when
the LED is on continuously most of the time, but if this is not achievable the unit will still
function correctly as long as the LED is flashing green but not flashing rapidly. If the
AUDIO LEVEL indicator flashes rapidly, the audio input level is too high, and audio
distortion may occur.
6. Noise Cancellation
The DSPKR STATUS indicator will
initially show Red to indicate that noise
cancelling is off. When the FUNCTION
button is pressed momentarily, the unit
will step through the noise cancelling
levels and the STATUS indicator will
show Orange. Every time the
FUNCTION button is pressed, the
speaker will emit a short tone, and the
unit will step up to the next filter level. A
double tone will be heard when the maximum level of noise cancelling is reached. A
further press at this stage will send the unit back to Noise Cancelling OFF mode. Use this
feature to select and store your desired filter level (6.1). Note: If the volume is too high it
may be difficult to hear the beep.
7 filter levels table
Noise
Cancelling STATE Indicator Tone Reduction
(dB)
White Noise
Reduction
(dB)
OFF Red None None
1 Orange 4 9
2 Orange 5 11
3 Orange 6 13
4 Orange 8 15
5 Orange 16 17
6 Orange 21 20
7 Orange 25 24
STATUS LED

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6.1. Storing and un-storing a selected level of noise cancelling
Once a suitable filter level has been selected, this level can be stored. This is achieved by
pressing the FUNCTION button for a few seconds. The unit will respond with a tone and
the STATUS indicator will turn Green. Having stored a desired level, brief presses of the
FUNCTION button will now cause the unit to cycle between noise cancelling OFF
(STATUS Indicator – RED) and noise cancelling ON at the saved level (STATUS Indicator
– GREEN). To un-store the saved level, press and hold the FUNCTION Key again until
the unit emits a tone. The STATUS indicator will change back to Orange and the unit will
now cycle through the various levels of noise cancelling. Note: It is advisable not to drive
a vehicle and change the filter level at the same time.
Note:
Higher levels of noise cancellation will remove virtually all the background noise, but the
user will note that the audio may be slightly distorted if high levels of background noise are
present. Switching off the noise cancellation will restore the audio. If there is a lot of noise
present on the audio signal it may be necessary to increase the output volume when
listening with the noise cancellation switched on, once the noise has been removed. If the
volume is increased and the noise cancellation is then switched off, the resulting
unprocessed signal will be at a higher level. Care must be taken to avoid excessive signal
levels to avoid possible damage to your hearing or equipment. bhi Ltd does not accept
responsibility for damage to equipment or hearing however caused.
7. Sleep mode
With power applied to the speaker it can be manually put to into sleep mode by pressing
and holding the FUNCTION button for approximately 6 seconds. You will firstly hear a low
tone then after approximately six seconds a high tone, releasing the button after this will
leave the speaker in sleep mode. The unit consumes very little current (3mA) and the
STATUS indicator flashes red every 15 seconds to show that it is still powered.
7.1. Waking the unit up
To wake the unit up, simply press the FUNCTION button momentarily and the unit will start
to operate in the last mode it was set to.
7.2. Auto sleep function
If the unit fails to see any audio above the minimum required level for greater than 30
minutes, the unit will place itself into Sleep mode. The unit consumes very little current
(3mA) and the STATUS indicator flashes red every 15 seconds to show that it is still
powered. To wake the unit up, press the FUNCTION button and the audio will be
restored.
8. Specifications
DC Power
DC input voltage 10 to 16 Volts DC.
Current 2 Amps maximum
Protection Over current and reverse polarity protected

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Audio Input
Impedance Terminated with approximately 8 Ohm load
Minimum input level 80 to 500 mV (for correct working levels)
Maximum 6 Watts (maximum withstand)
Audio output
Impedance Internal Speaker 8 Ohms (Nominal)
External speaker/phones 4 Ohms (minimum)
Level 10 Watts R.M.S. nominal (with 12V DC. supply)
Controls Single power/function button
Volumecontrol
Indications Power ON/ FUNCTION
AUDIOLEVEL
Connections 2.1mm DC power jack
3.5 mm mono, external speaker/headset socket
Integral 2M long 3.5mm mono jack plug lead (audio input)
9. Troubleshooting/FAQs
Speaker doesn’t work at all, no sound from the speaker:
•Check that the power connector on your power supply is suitable for the power
socket on the speaker (2.1mm, centre positive). Check the fuse. Check
connections to your power supply.
•Check that you have switched your radio communication equipment on and that you
have a signal for the speaker to process. To verify this, remove the audio connector
from the external speaker socket on your equipment.
•Check that the AUDIO LEVEL LED is illuminating green.
The speaker works but the noise cancellation doesn’t appear to improve the audio
quality of the signal:
•Check the filter is switched on and increase the level to see if this makes any
difference.
•Check that the AUDIO LEVEL LED is illuminating green.
4. Troubleshooting/FAQs
The volume from the speaker is low and cannot be increased:
•The speaker is designed to work with external speaker sockets of radio
communications equipment, and although it will work with some earphone and
headphone sockets, there may be occasions where the signal output from these is
not enough for the speaker electronics to process the signal effectively. bhi have
another product that will work with these levels of signal, the NEIM1031MKII (DSP
Noise Eliminating In-line Module). Please contact bhi for more information.
Sometimes there is a short delay before the noise cancellation is active:
•This is due to the time the DSP takes to start processing the signals. This gives you
the opportunity to check that the DSP is not taking out any detail from the signal.
Sometimes I can hear a processing sound in the speaker when no signal is present:
•This is normal and is caused by the DSP processor. When a signal is applied you
should not be able to hear this in the speaker.

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I can hear noises/speech in the speaker when I transmit:
•The DPSKR has been specifically designed to minimise against the effects of stray
RF. If you do hear noises in the speaker, this is probably due to high levels of RF
being present in the vicinity. Carry out the standard checks necessary to minimise
this. 1. Make sure that the 3.5mm black audio lead and the red/black fused DC
power lead are routed away from sources of electronic interference or RF cables.
2. Try using a separate DC power supply for the DSPKR. 3. Reduce the volume on
your radio in steps and then increase the volume on the DSPKR to compensate (as
long as the input LED still flashes green the input level is ok) until the RF
disappears. 4. Fit ferrites to the leads at outlined on the bhi website FAQ page
(http://www.bhi-ltd.com/index.php/support/faq.html).
10.bhi support
Every DSPKR noise eliminating speaker comes with a 12 month guarantee against
defective materials and workmanship. If you do have a problem then please refer to the
troubleshooting guide (section 9). If you have not resolved your problem then please
contact us. Before you make your call please have the following information to hand:
1. Your serial number (found on the back of the unit).
2. Details of when and where you purchased the unit.
See our website for FAQs for answers to other common questions; otherwise most queries
can be resolved over the telephone or via email. If not we will arrange with you to have
your unit sent back to us for analysis, repair or replacement (if within 12 months from date
of purchase, if outside the guarantee period an estimate of the cost of repair will be given).
For contact details please refer to the back cover of this manual. If you have any
suggestions for improvements please complete and return the customer feedback form.
Note: Opening the case will void any warranty unless agreed beforehand by bhi Ltd.
No user serviceable parts inside.
Weee Statement for correct disposal of this product:
(Applicable in the European Union and other European countries with separate
collection systems). This marking shown on the product or its literature, indicates
that it should not be disposed of with other household wastes at the end of its
working life. To prevent possible harm to the environment or human health from
uncontrolled waste disposal, please separate this from other types of wastes and recycle it
responsibly to promote the sustainable reuse of material resources.
Household users should contact either the retailer where they purchased this product, or
their local government office, for details of where and how they can take this item for
environmentally safe recycling. Business users should contact their supplier and check
the terms and conditions of the purchase contract. This product should not be mixed with
other commercial wastes for disposal.

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bhi Ltd
PO Box 318
Burgess Hill
West Sussex
RH15 9NR
England
Telephone: + 44 (0)845 217 9926
Fax: + 44 (0)845 217 9936
Email: [email protected]
Web: www.bhi-ltd.com
1072-105D iss B