| Forensic
Audio
Music places certain demands on
its tools when performing restoration and enhancement.
The goal in music restoration is to remove as much noise as
possible without introducing artifacts and to leave the
remainder as "musical" as possible. With
Forensic Audio, we are not constricted by these guidelines.
The only goal, in most cases, is to audibly discern what is
being said by certain individuals so that audio, previously
obscured by noise can now be heard and understood. With
those goals in mind, tools can be augmented to better service
this different need. Though several important forensics
audio applications can be performed with both our DC
Millennium software and our DC SIX product, our DC
LIVE/Forensics is designed to specifically deal with voice
enhancement in situations where ambient noise is a major problem.
General Recording
Techniques
Of
course, no tools such as these would exist if in fact all recordings
were perfect. And in this world of hidden microphones,
wiretaps and other listening devices, odds are that products like
this will have a long and hopefully prosperous life, there are some
basics to recording that should be followed; regardless of the
situation.
Get
the levels right: Shoot for the Middle!
It is
important to get good levels on any system. But too much level
can be just as bad as not enough level. Shoot for the middle
of the road and hope for the best. You're much better off in
today's world of digital enhancement starting with lesser levels
than you are with overloaded and distorted files. With digital
devices...unlike the analog days, when you danced the VU meters in
the red to get the best recording...red means distortion. 0 dB
is too hot and there's really little that can be done for severely
clipped audio. We can always perform a gain adjustment on
something too weak, but fixing distorted and clipped audio is a
little bit trickier.
Two
mics are better than one
Especially
in areas where ambient noise is a problem, always try to place
two mics...one that monitors the room and one as close to the
subjects as possible. This not only gives you two
streams of audio to choose from, but also gives filters like
DSS a viable room monitor feed to subtract from the vocal
feed.
Check
Your Equipment
Even
the best systems fail from time to time, but you can eliminate
correctable problems by running a simple test before your
evidence is on the line. Make sure you check your levels
and batteries numerous times to verify their integrity before
they leave you red-faced or worse. Also verify that your
mics are secured so that they don't fall or tip over during a
recording.
Specific Forensics Tools In
DC LIVE/Forensics
Successful Audio Forensics depends on trying
a variety of methods until you find the one that achieves the
best results. DC LIVE/Forensics provides a menu of
specific Forensics tools which we'll list below, but there are
also an assortment of non Forensics tools which may help in
certain situations. This list only deals with those
tools designed primarily for DC LIVE/Forensics.
| DSS
Filter |
The new DSS
feature in the DC Live/Forensics software is a unique
and powerful tool capable of recovering speech from
recordings containing loud music or other coherent
noise. Until
now, a recording that was covered or masked by loud
music was basically a lost cause.
DSS decoding is designed to make it possible to
attenuate this music and uncover the speech. |
| Adaptive
Filter |
This
filter is used largely in audio applications where the
ambient noise environment is constantly changing and the
filter coefficients must automatically change to
maintain good intelligibility of an audio signal. The
Adaptive filter adjusts itself to remove a modeled
signal representing the unwanted time domain waveform
while preserving the target signal. |
| AFDF
Forensics Filter |
The
Forensics Adaptive Frequency Domain Filter (AFDF) is a
variation on the basic theme of the Auto Spectrum CNF
filter mode. The
primary difference is that the Forensics AFDF is
optimized for Forensics oriented files and not “High
Fidelity” files.
It has a faster response time and a narrower
effective bandwidth while producing higher levels of
noise reduction at the expense of potentially producing
higher levels of digital artifacts.
The AFDF Filter is “Adaptive”, which means
that it will automatically adjust itself to varying
noise environments and no noise sample must be
taken. It is fast and easy to use with little or
no training, but can garner incredible results. |
| Polynomial
Filter |
This
allows the mathematicians, scientists, and engineers to
create their own transfer function using a polynomial
expression. For
those not so inclined, there is a plentiful assortment
of presets to choose from.
|
| Spectral
Filter |
This
filter allows you to create a very high-resolution
frequency response contour using up to 32,000 bands of
equalization by using FFT techniques.
The user interface system is intuitive and allows
you to zoom-in on a particular portion of the spectrum
that needs accurate and specific frequency response
contouring. By using the right mouse button, you can add
bands, or delete them simply by pointing and clicking on
the graph.
This is very useful in Forensic audio
applications for removing in-band and out-of-band
extraneous noises because of its high degree of
frequency selectivity and its very steep slope
characteristic. |
| Spectrogram |
A
Spectrogram provides a method for displaying waveform
data including Time, Frequency and Intensity all on the
same graph. Time
is represented on the horizontal (X) axis, frequency is
represented on the vertical (Y) axis, while intensity
(loudness) is represented by color or gray scale. The
Spectrograph displays itself in the Destination window
when this is checked.
The Spectrogram is calculated for whatever
waveform is displayed, highlighted and zoomed in on in
the Source window and is time aligned with the same.
|
| DeClipper |
The
De-Clipper can be used to repair signals, which were
either clipped by digital or analog mechanisms.
It performs its magic by detecting signals with
very low or zero values of slope (user adjustable from 0
- 0.5) above a settable threshold amplitude value.
When this condition is detected, the routine
mathematically interpolates a new signal and replaces
the zero slope portion of the bad waveform with one
containing curvature. |
| Flashback
Recording |
Flashback is
primarily designed to be used in real time intelligence
gathering and Forensics surveillance situations.
It is a feature that allows you to go back and
listen to something that you may have heard during real
time operation of the software that may be of immediate
interest and needs rapid clarification. |
| Dual
Stream Recording |
In
a world where all evidence is called into
question...especially audio computer evidence, our
software automatically logs an unedited raw version of
your recording along with the enhanced version that
you're using to gather intel. You've always got a
safe backup! |
| VOX
Record Activation |
This
feature allows the recorder to start and stop
itself based on the presence or lack of presence on an
audio input signal.
The recording activation process is triggered by
signal level sensing as determined by your setting of
the Trip Level control.
The record de-activation process is triggered by
a combination of the signal level sensing system in
conjunction with the Minimum Duration control setting. |
| Auto
Date and Time Stamp |
By
checking the box labeled Automatic VOX Time/date Stamp,
Live will add a marker each time recording starts in VOX
mode. This
is useful in remote location or surveillance recording.
By enabling this function, LIVE will record only
when audio is actually present to be recorded and each
recording event will be marked with the exact time and
date of the individual recording. |
| Unlimited
Recording Time |
Windows
has an inherent 2 Gig limit for wave files. This
can be a problem for very long recordings. With
our products, the system automatically starts a new file
every time the 2 gig limit is reached and never misses a
beat. |
| Brick
Wall Filter |
Very
steep digital filters used to attenuate signals that are
interfering with a poor quality audio signal.
These are FIR (Finite
Impulse Response)
filters that exhibit a very high degree of out of band
attenuation. |
Choosing The Tools
For Audio Forensics, Enhanced Audio offers 2 choices. DC
LIVE/Forensics at $1399 and the DCVST Automatic Forensics Filter VST Plug-In at
$399. There's a brief summary below so you can better understand the differences in the two products.
|
 
DC
LIVE/Forensics $1499 | 
DCVST
Automatic Forensics Filter- $399 |
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30 Band Graphic EQ
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Flashback LIVE Review.
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Real Time Coefficient Display Added To The Adaptive
Filter
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Dual Stream Recording Added To LIVE Feed
through
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Time Domain Adaptive Filter and Frequency Domain Adaptive Filter
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CD Ripping
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Turbo-Charged Algorithms
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Elimination of 2 Gig Windows Wave File Limit
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Audio Spectrograph
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Polynomial Filter
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Spectral Filter (Up to 32,000 Band Graphic EQ)
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Normalized Adaptive Filter
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Live Log To Disk with Notation and Automatic Time Stamp
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DeClipper
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Spectral Subtraction Filter In Continuous Noise
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Wave file to MP3 Conversion via popular encoders
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Signal Triggered VOX Recording
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Distortion Analyzer
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Up to 192 kHz Sampling Rate Support
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More Info?
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One Button Control
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| Based on the Popular AFDF
Frequency Domain Adaptive filter contained within our Continuous Noise
Filter
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| Delivers Realtime Results
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Easy To Use
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Fast Results
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Works with any VST audio program
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Powerful filter automatically adapts to changing noise
environment
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No noise sample necessary
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More Info?
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Screen Shot
LIVE mode can be a wonderful tool for
surveillance or other live monitoring. An audio signal can be
filtered and listened to while it is happening live. Great for
both law enforcement and military uses. Both processed and an
unprocessed signals are recorded at the same time and a listener can
even rewind to rehear a bit of audio even while live recording
continues. This
screen shows you the MultiFilter in LIVE mode.
An Educated Taste Test
How much of a difference can the Enhanced Audio
products make in your audio life? Why don't you try them for
yourself? We have demos and Getting started tutorial guides
for both products listed below. Download both the demo and the
Getting Started Tutorial guide...the tutorials don't take a great
deal of time, but they give you a fantastic idea just how powerful
our products are.
We've provided guides for both DC
SIX and DC LIVE/Forensics. The DC Six version help get you
oriented with some traditional music projects, but then proceeds to forensic
specific uses. The Getting Started Guides are in PDF form and only depend on you using the demo versions of both products. These tutorials do not take a great deal of time, but they are jam-packed with info and perfect for
quickly learning both products. These are PDF files and best viewed with Adobe Acrobat. This is a free software product that you can download at www.download.com
Example Files
This
type of noise can be found on typical forensics
recordings. You'll notice the success that DC
LIVE/Forensics has in removing this noise.
Noisy
Recording
After
DC LIVE/Forensics
Note: On some machines, you may notice a hesitation at the beginning of your MP3 files when you click on them. If you just let it play and then listen to it again, the hesitation will go
away. If you're using a dial-up...it's probably best to download this files and listen once you've downloaded.
Training,
Training, Training
No
one is born an expert on Audio Forensics. This is the
reason why we have annual 3 day training courses scheduled
throughout the year. Not only does this course focus on
the intricacies of our DC LIVE/Forensics product, but it also
deals with gathering evidence, storing evidence and preserving
the chain of evidence so that you have full confidence in your
output should you ever need to testify in court. If
you are interested in being considered for these courses, you
can click here for
additional information or email us at sales@enhancedaudio.com
so that we can email you when we schedule our next training.
Will I Need Anything Else?
If you have DC LIVE/Forensics
and a reasonably good sound card, you have an audio lab that
will compete with any audio setup...even if your competitor
had a much larger budget. These products are powerful
and most importantly, flexible.
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| Popular
Products |
Personal
Forensics Investigation
$99
Evaluation
Maybe you
have a cell phone recording, maybe it was a digital
recorder...you hear muffled voices in the background. What are
they saying? Not knowing has been eating at you and you need
answers. You've seen advanced forensics tools on television,
but you know nothing about audio and even less about
clarifying a spoken voice on a recording. |
|
DC
EIGHT
$159
This
new flagship product offers features that any restoration
enthusiast would love with no fat. We don't try to be all
things to all people, but if you want the world's best audio
restoration...stop lookin. |
|
DC
8 Software Training DVD
$39
Our resident
software guru comes into your home via our DVD and walks you
through tips and tricks for maximizing the quality and speed
of your restoration results. You'll be amazed at what
you can learn in 2 hours. |
|
Better
Audio Restorations Training DVD
This
detailed introduction to the Zen of Audio Restoration features
a beginner's guide to restoration
software.
Make the most of your restoration software
$39 |
|
DC
LIVE/Forensics
There is
simply no better Audio Forensics product on the market.
You can pay thousands more, but if you're clarifying noisy
recordings or even running live audio surveillance, DC
LIVE/Forensics is the best in the business. $1499
|
|
Advanced
Forensics Concepts Using DC LIVE/Forensics DVD
The in depth
walkthrough covers all of the great new features of
DC/LIVE/Forensics 7.5. $59
|
|
Audio
Mentor
New Price
$29!
This
intelligent wizard helps any user instantly achieve
spectacular results. Mentor takes you by the hand and
gets you from the Record or Tape to CD in several painless
steps.
|
|
Learning
The CNF DVD
Go
"under the hood" of the continuous noise filter.
This in depth training course will help any level user achieve
better results with this powerful filter.
|
|
Computer
Transfer Preamps
New thinking
for your vinyl restoration. These preamps give you the
most accurate reproduction off of your record that is
available...at a price you won't believe |
|
Automatic
Forensics Adaptive Filter VST Plug-In
Now you can
get one of DC LIVE/Forensics most powerful automatic adaptive
filters and plug it into the software of your choice.
This cool new VST plug automatically removes noise so that you
can find a voice buried beneath the muck. Only $399 |
|
Virtual
Valve Tube Simulation VST Plug-In
Add real tube
sound to any music file an instantly add the warmth and depth
that only real tubes can provide. This new VST Plug In
is useful in so many ways that you'll instantly find it your
favorite plug-in. Only $99
|
|
DC
8 Software Training DVD
$39
Our resident
software guru comes into your home via our DVD and walks you through
tips and tricks for maximizing the quality and speed of your
restoration results. You'll be amazed at what you can learn in
2 hours. |
|
Better
Audio Restorations Training DVD
This
detailed introduction to the Zen of Audio Restoration features a
beginner's guide to restoration
software.
Make the most of your restoration software
$39 |
|
DC
LIVE/Forensics
There
is simply no better Audio Forensics product on the market. You
can pay thousands more, but if you're clarifying noisy recordings or
even running live audio surveillance, DC LIVE/Forensics is the best
in the business. $1499
|
|
Advanced
Forensics Concepts Using DC LIVE/Forensics DVD
The in depth
walkthrough covers all of the great new features of
DC/LIVE/Forensics 7.5. $59
|
|
Audio
Mentor
New
Price $29!
This
intelligent wizard helps any user instantly achieve
spectacular results. Mentor takes you by the hand and
gets you from the Record or Tape to CD in several painless
steps.
|
|
Learning
The CNF DVD
Go
"under the hood" of the continuous noise filter.
This in depth training course will help any level user achieve
better results with this powerful filter.
|
|
Diamond
Cut
Millennium
Powerful
Audio Restoration and enhancement product. Only $59
|
|
Computer
Transfer Preamps
New
thinking for your vinyl restoration. These preamps give you
the most accurate reproduction off of your record that is
available...at a price you won't believe |
|
Automatic
Forensics Adaptive Filter VST Plug-In
Now
you can get one of DC LIVE/Forensics most powerful automatic
adaptive filters and plug it into the software of your choice.
This cool new VST plug automatically removes noise so that you can
find a voice buried beneath the muck. Only $399 |
|
Virtual
Valve Tube Simulation VST Plug-In
Add
real tube sound to any music file an instantly add the warmth and
depth that only real tubes can provide. This new VST Plug In
is useful in so many ways that you'll instantly find it your
favorite plug-in. Only $99
|
|
|
