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Podcasting Hacks
By Jack Herrington
August 2005
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HACK
#50
Choose the Right Audio Tools
Download free audio software, and spend your money wisely on the right commercial audio software
[Discuss (0) | Link to this hack]

A wide variety of free and commercial audio tools are available for podcasting. But that doesn't mean it's easy to find the right software. You can spend a lot of money on an application that is great for musicians but doesn't have the right functions for podcasters.

In this hack, I cover both the free and commercial tools, explaining which ones are good for podcasting, and why.

Audio Editors

Audio editing applications allow you to edit sound as though you're using a word processor. You can cut, copy and paste, delete, and arrange sound in any way you choose. Most of these applications allow you to work with multiple tracks that you can think of as sonic layers. You can use these tracks to work with each sound in isolation, and then mix down to a single mono or stereo signal at the end. In addition, many of these applications allow you to apply effects to the volume or the character of the sound.

Audacity.

Audacity (http://audacity.sf.net/) is a free sound editing program that runs on Windows, Mac, and Linux. You should download Audacity and install it right now. It's an excellent starter program and it's possibly the only editing program you will ever need. shows the Audacity main window.

On the recording side, Audacity supports mono and stereo recording from any sound input source on your machine. It even has meters in the document window to show when you are clipping (cutting off a portion of the signal). Unfortunately, plug-ins are not supported during recording. So, you will need to do all the filtering work after the recording.

Audacity has excellent editing capabilities. You can zoom and scroll on both the time axis and the amplitude axis. The keyboard controls for navigating around the document and then creating and extending your selections are easy to use. Cut, Copy, and Paste all work as if you were in a word processing document. However, copying and pasting between documents of different sampling rates can get tricky.

Audacity supports envelope editing. With this feature, you can manually boost or reduce the amplitude of parts of the recording using simple visual cues. This is very handy when you have sections of audio that drift from very soft to very loud.

Figure 1. Audacity's main window

When you download Audacity, you should also grab the LAME MP3 encoder and the Virtual Studio Technology (VST) plug-in support module. VST is a plug-in standard that is supported by a number of sound applications on both Windows and Macintosh. Audacity has a variety of filters already baked in, but the VST plug-in support expands your sonic toolkit tremendously.

Pro Tools free.

Digidesign (http://www.digidesign.com/) is so cool that it released one of its earlier versions of Pro Tools completely free to the public. Pro Tools is a commercial-quality recording application that, in its current version, is coupled with the company's Mbox hardware .

Unfortunately, this version works only on Windows 98 and Mac OS 9. It does not work on the Classic emulator on OS X. If you are running on Windows 98 or OS 9, this is a heck of a bargain. Some Macintoshes can dual-boot between Mac OS X and OS 9 to save you a lot of money.

DSP-Quattro 2.

Another high-end sound editing package for Macintosh is DSP-Quattro 2 (http://www.i3net.it/Products/dspQuattro). The list price is around $149. It supports region editing as well as both VST and AU effects plug-ins, and has an intuitive interface for making your edits. For the price, this is an awesome sound editor.

Sound Forge.

Sony's Sound Forge (http://soundforge.com), which is pictured in , is a full-featured, multitrack recording and editing application for Windows.

A full complement of effects is built in, but it also supports the VST plug-in standard so that you can add your own effects. An audio editor is built into the product, as you can see in in the lower righthand corner of the main window. The package includes noise reduction tools that will help you clean up sub par recordings.

Figure 4. Sony's Sound Forge application

If video is your thing, you can import video and sync up your audio editing with it. If creating music loops is more your style, this program integrates with Sony's ACID program. You create the loops here and then use ACID to choreograph them into a song.

At the time of this writing, Sound Forge sold for $299.95.

n-Track Studio.

n-Track Studio (http://fasoft.com), written by Flavio Antonioli, is a multitrack recording and mixing program for Windows. It's relatively inexpensive at $49 for the limited edition and $75 for the full version. n-Track Studio is shown in .

A demo is available online that you can use for a limited time, to get a sense of its features. It has a pretty daunting interface, but once you get the hang of it, you can get to recording and arranging pretty quickly. It does not have a built-in signal editor, so you will need Audacity or Sound Forge to edit your recordings directly.

Figure 5. n-Track Studio

Sound Recording Applications

A few applications specialize just in the recording of sound. Some of these subspecialize in taking sound directly from applications in addition to traditional sources, such as microphones.

Total Sound Recorder.

The inexpensive Total Sound Recorder (available at: http://highcriteria.com/) is a favorite of Windows podcasters. The standard edition costs $11.95, and the professional version costs $39.95.

You can use the Total Sound Recorder Pro main window, shown in , to record audio from all the standard input sources, as well as from applications.

Figure 10. Total Sound Recorder Pro

Audio In.

Another freeware recording tool is Audio In (http://home3.swipnet.se/~w-34826/). This is a nicely put together application that does one thing, record sound from any input, and does it well. As you record, an attractive oscilloscope display shows the signal.

Podcasting Applications

With the advent of podcasting have come specialized podcasting applications. These applications combine sound recording, rudimentary editing, and mixing, and also automate the encoding and uploading process.

Winpodcast.

One of the first podcast authoring applications is Winpodcast (http://podcast.scon.de/). It has a recorder, show notes, and a cart interface, all built into one application. This application is still in its early days, but it looks promising for simple podcast productions.

MixCast Live.

MixCast Live (http://mixcastlive.com/) is the first Macintosh podcasting application. It has a show notes area, a cart for samples, and a recorder built into the application. It was prereleased at the time of this writing. The purchase price was $59, but you could get a $20 discount if you wanted to take the leap early.

Propaganda.

The oddly named Propaganda (http://www.makepropaganda.com/) from MixMeister Technology is a Windows podcasting application that costs $49.95. Segments can be recorded and multitrack mixed in the application. Then the show is encoded and uploaded to your site using a built-in file transfer mechanism. The application also handles creating the RSS 2.0 XML file for the podcast and uploading it to your site.

Helper Applications

Here are a few more applications that will help you develop your podcasts.

Soundflower and Soundflowerbed.

Soundflower (http://cycling74.com/products/soundflower.html) is a handy sound routing utility for Macintosh. It creates two virtual sound drivers: Soundflower 2Ch and Soundflower 16Ch. These drivers support 2 and 16 channels, respectively.

The value of Soundflower is that you can specify a Soundflower port as the input or output of any application and then route sound through to it from another application. For example, you can route the output of Skype or iChat through Soundflower and into a recording application, thus recording the output of a Skype call .

Soundflowerbed, available on the same site, is a handy helper application that allows you to monitor your Soundflower channels.

FuzzMeasure.

FuzzMeasure (http://www.supermegaultragroovy.com/products/FuzzMeasure/) measures the noise in your signal path and environment. It's a $49.99 application, but the company has a demo download that you can use to get some results if you are merely curious. The application actually simulates the environment using white noise and then calculates the response from the signal path and the environment.

Frequency.

Frequency (http://home3.swipnet.se/~w-34826/) is a freeware application for Macintosh that provides an image of a sound source of the frequency domain. When editing sound, we normally look at audio in the amplitude domain. We see the audio signal as it moves up and down in waves over the time axis.

Another way to look at sound is in the frequency domain. We do this when we look at a graphic equalizer. Each bar represents a frequency and the height of the bar is the amount of volume present at that frequency.

Working with Frequency is like looking at a graph of these graphic equalizers laid out along the recording's time axis. The darkness of the band indicates the intensity at that frequency. shows the Frequency main window.

Through the miracle of really tough math, you can also edit in the frequency domain, literally removing or adding sound by frequency rather than by changing the signal itself.

Figure 12. Frequency main window

Practical applications for a podcaster working with just her voice and some effects are somewhat limited. But you can use the tool to determine the frequency of particularly nasty transients and noise, and even remove them.

Another free application that works in the frequency domain is FFTea (http://oomz.net/FFTea/index.html). At the time of this writing, the 1.0 version had been released but a bunch of features still were missing.

See also: <ul/>


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