AUDIO
RESTORE GUIDES -> SoundForge Filters
This is a visual guide to using audio correction
filters in SoundForge. This has been tested in Sonic Foundry
SoundForge 6 but should work well in both Sonic Foundry
SoundForge 5 and Sony Digital SoundForge 7. For those
unaware of the buyout, SoundForge is now a Sony product.
This guide shows samples of some filters (available in the
download file) and an explanation for the proper scenario in
which to use it. Most of these filters use the PARAGRAPHIC
EQUALIZER tool. This seems to be the most accurate method
when using SoundForge because it gives both numeric and
visual data.
Download
the filters
Click
here to download the official digitalFAQ.com SoundForge
ParagraphicEQ/Normalize presets file, which adds more than
50 new filters to SoundForge. This will save you some setup
time, however it is still important to read this guide to
learn how to actually use the filters. You will also need
the freeware SoundForge
Presets Manager from Sony to install them. After you
install the SF Presets Manager, and after you download and
unzip the digitalFAQ.com filters pack, open the SF Presets
Manager software. Open the filter pack, and then drag the FX
Plugin items (Paragraphic EQ and Normalize) from the top
(presets) to the bottom (system). Close the Presets Manager
and start SoundForge to use these new filters.
Understanding
the SF interface
SoundForge is often called "the Photoshop of
sound" and it deserves this distinction. Why? Well,
much like Photoshop, the program can be used as basic or as
advanced as the user wants. It appeals to users of all skill
levels, and has few limitations. The software is normally
limited only by a user's own skills and creativity, and not
the fault of the program itself. Most controls needed for
video-based audio are located in the PROCESS area. This
image below shows how to find the EQ (Paragraphic) and below
that is the NORMALIZE function:
General
Audio Notes
Try to not over-filter audio!
Editing audio with the
Paragraphic EQ is essentially a form of frequency carving.
You remove the bad parts of the signal, and then enhance the
good parts of the signal. Do not use more than 1-3 filters
on an audio clip.
Be careful of clipping! Altering the EQ of a file can
raise and lower the depth and scope of the audio, so be
cautious of "red-lining" the file (clipping), as
it can corrupt the quality with cracks and other noise. This
is why it is important to normalize AFTER all quality
corrections have been made, as well as why audio files
should NOT be captured at peak volume levels. Please see the
FAQ for more information.
WARNING! Turn your
speakers down now. Once the realtime preview has begun, turn
them up. Some of these filters tend to make audio both
louder and quite shrill, especially the (VoltX) high restore
filters.
Paragraphic
Equalizer overview
An equalizer is an option to augment the sound of an
audio file. Anyone familiar with a high-quality stereo has
probably seen a very basic paragraphic EQ. It's normally the
3-10 little notches that can be moved up and down to raise
and lower the tone at various frequencies. But the
paragraphic EQ in SoundForge is much more complex. Using
these controls, you can remove hiss, raise or lower pitch,
remove noise ... basically just correct the audio quality of
the file.
Unlike some software, SoundForge also has realtime
previewing of the audio changes. Tick and untick the
"BYPASS" box to compare original audio (bypass
checked) to the filtered audio (bypass unchecked). Use this
feature to your advantage.
Since this site is aimed at transferring video to
DVD, these audio filters are set to reach the same goal.
These are meant to remove the most common problems
videographers face: removing hiss, restoring high tonal
values to mono/lossy recordings, and to remove errant noise
(often from shoddy microphones). There are four categories
of paragraphic filters
Paragraphic
EQ - Hiss Removal filters
These filters offer different levels of hiss removal. Just
be careful when using them, as it can also muffle the sound
if done improperly or you use the wrong filter for your
given situation.
Try the small ones first. Try to use the standard HISS
CUT as much as possible (the one included with SoundForge).
If that is not strong enough, move on to the
"alternate" filters. Try to find the one that
removes hiss while leaving the high tonal values as intact
as possible.
Stronger hiss filters. The "Alternate 2"
and "Alternate 6 (dss)" are for severe hiss
problems, and may muffle some, depending on the source. Use
sparingly on audio.
Combo: Hiss removal, maintaining high tone from high
restore. This filter is for removing hiss that appeared
after a high restore was performed. High restoring
essentially broadens the higher frequencies, but that is
also where most hiss is stored. This filter will remove the
new hiss, but without undoing the high restore. This is
especially useful on mono VHS tapes. The "high"
and "low" variations are for controlling the bass
levels.
Paragraphic
EQ - Noise removal/correction filters
These filters have been especially good on downloaded
files, aging VHS footage, home videos, audio cassettes and
records. These sources often have corrupt or noisy audio due
to the storage media or the recording equipment used to make
the source.
Remove low rumble and harsh bass. These filters are
for files that have too much bass, too low of a tone, rumble
noise, or a rumbly sound. The "Remove Low Rumble"
setting is a default SOUNDFORGE 6 filter. The presets has
some added variations of this filter.
Remove AC/Fan noise and audio whine. These filters
remove high pitched sounds like artificial whining, wind
movements, and motor noises caused from air conditioners and
fans. These are often useful on home movies shot outside or
with cheap microphones.
Paragraphic
EQ - Restore High Tones
A big problem with early VHS tapes is that they were all
monaural sound (mono). Even through the early 1990s many
VCRs used mono sound as the de facto recording standard,
especially the low budget models. Mono sound, at least on
VCR recordings, tends to have lower tonal depth that is a
far cry from the DD5.1 we insist on today. These problems
are also found on old homemade vinyl and cassette
recordings.
Normal usage. The most commonly used filters in the
presets download are High Restores H, I, J, G and E. The
rest of them are for more specialty use.
Paragraphic
EQ - Combo Filters
Combo filters aim to achieve more than one goal. In the
sample image below, the high restore filter has a goal of
restoring the high tones, but without adding more hiss.
There are several combo filters found in the presets file.
Some remove whine and hiss, buzz/hum and hiss, high restore
and remove hiss, etc.
Normalizing audio
See the Audio Restoration FAQ for more theory details. Some
of this is reprinted from that guide found on this site:
One of the largest problems with homemade DVDs is a lack
of proper audio richness. In addition to be properly attuned
(like having a proper tonal range free of hiss), it must
have a full body for proper presentation. Most people
confuse full body with volume. While a full sound is indeed
louder, it is not due to volume control.
1. Never raise or lower the
"volume" of the audio file - NORMALIZE it !!
2. Never normalize BEFORE adjusting the tonal values or
removing noise (if needed) !!
Not too high, only 80 percent. One of the biggest
mistakes made by those capturing audio is to overdo it or
underdo it, resulting in corrupt peak values and other
decay. I see many guides that say "use Besweet and tick
the normalize function" or "raise capturing volume
all the way up" which results in arbitrary values
usually nearing the 100% peak value range. Most movies
appear to use a range of 70-90% for their audio. Their
values are not contoured to have 100% values, as it can
crack or otherwise distort on some audio playback equipment
(as it does on one of my tv sets).
Not too low. Inversely, many never pay attention to the
computer audio controls during capture, and leave it at MS
Windows default volume levels. They fall in the 25-50%
range. Only is special situations would you keep volume at
such a low level. Turning up this volume on the tv will
actually result in raising the hiss level. Capturing audio
at low volumes results in a captured file with a minimal
level of normalization and severe tonal flaws. You cannot
fix it by trying to adjust the "volume" in
software after-the-fact.
SoundForge filter. This is the 80% value curve based
on peaks that I suggest for all DVD-Video applications. Goto
PROCESS -> NORMALIZE to initiate the filter:
You are now ready to use this audio and author a DVD.
This guide took quite a bit of time to create, between
creating the presets files and the images and descriptions
found above. If this has helped you in any way, please
consider making a donation to this site.
Page Last Updated: May 14th 2005
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