Sonic Foundry Acid Pro 4.0

Sonic Foundry Acid Pro 4.0

Byline: Frank McMahon

If you are not familiar with the program Acid Pro, you should be. It might be the best audio tool a video producer could have. I have been an avid Acid Pro user for several years now, and I’ve enjoyed the new professional features in every robust update.

Recently I had completed editing a DV movie, Glimmer, a psychological thriller about a female photographer who sees images in other people’s portraits, and I had a musician lined up for the score. But when I received his music and started laying in the tracks, it just didn’t gel. The music was amazing, but it was the wrong mood. I was on a tight deadline, as the movie was set to debut at a film festival in 48 hours!

So what to do? Using Acid Pro, I scored the movie completely within two days. Acid came through with finesse. In fact, if you think of the program as a loop generator for doing techno, you need to think again. I primarily used one of Sonic Foundry’s atmospheric loop collections (Robert Rich’s Liquid Planet) to create a moody and intense score. Not only is making music with the program amazingly intuitive, but the vast variety of the loop collections make it ideal for just about any project. Even if you have minimal musical background, you’ll be amazed at the soundtrack you can whip up with a little time and imagination.

When word of a new update hit, I knew I would have to get my hands on a copy. Version 4.0 contains a slight revamp of some existing features, as well as several new professional options.

One of the most welcome is support for 5.1 surround sound. The feature is implemented so that it blends right into the existing workspace. Switch the master bus mode from stereo to 5.1, and the program creates separate volume controls for all channels including LFE (subwoofer low frequencies). This attaches a surround mixer icon to every track. You can slide the direction of the sound around on the icon, or double-click it to bring up a larger version for more detailed arranging.

Imagine a quadrant with a center speaker, left- and right-front, and left- and right-rear speakers. A small diamond that sits in the center represents your track. Simply drag this small marker around, and the volume indicators on the speakers move up and down accordingly. Drag it to the right-front speaker and you’ll see the volume go up while the volume on the other speakers go down. In addition, you can change the orientation of the center for each track by adjusting the volume of the center channel. Adjustment movement tools let you lock movement to different axes. Set the sound to move only left to right or front to back. All the 5.1 sounds are keyframable, so you can create sweeps and pans and set them to different arcs of movement with the smoothness slider. With less smoothing, a sound will take a sharp turn; more smoothing means more of a natural, arcing movement.

Working with sound in three dimensions – OK, five dimensions – is very fun. However, a few things are needed to make it all work. Your current sound card may not cut it, so you’ll need either a card that supports 5.1 channel sound or a board with three stereo inputs. Another option is to stuff multiple soundcards into your machine – at least three – and use them to drive the tracks to your six speakers (oh yes, you’ll need five speakers and a subwoofer).

Another thing to keep in mind is that although Acid Pro 4.0 makes it easy to create surround environments, it does not do compression to 5.1 channel formats. The program works completely with uncompressed audio tracks. You can mix and arrange and play in full surround, but if you want to master to DVD or other delivery formats, you’ll need a separate encoder. But what a great opportunity for existing Acid Pro masters to expand their portfolio of sonic talents into the realm of surround.

Acid Pro has always supported automation via track envelopes with respect to features such as volume and panning. The new version extends this feature by allowing the automation of the parameters of plug-ins as well. Plug-ins that support the changing of effects over time now include Flange/Wah-Wah, Resonant Filter, and Track EQ. For example, instead of applying an EQ effect to a specific track, now you can set up an envelope to adjust the equalization to change over the course of your track. Very powerful. In addition, version 4.0 brings new envelope types: smooth, sharp, and hold. These envelope settings even map to an entire bus (a bank of tracks) for even more sonic options.

Acid Pro no longer locks you into a 4/4 time signature. You can change the beats to anything from 1/1 to 99/32. In fact, you can even change the signatures within a track or series of tracks by adding time signature markers.

ASIO drivers are a new addition to this updated version. Acid Pro has always supported many standard sound maps such as Microsoft Mapper, Wave, and WDM. Selectable during any project, ASIO in 4.0 offers professional users faster audible response times.

The Chopper module, used to slice and dice and create new loops, now offers loop cloning and makes it very easy to create new loops on the fly. Now all you need to do is open a track in the Chopper, grab a selection of the loop and drag the selection over to the track list. The program saves the section automatically and adds it as a new track. This is handy when you want to take one sound loop, dice it up, and layer it in different segments and durations.

MIDI fans have several new features to embrace. Now included in Acid Pro is a MIDI piano roll editor for creating, editing, and quantizing MIDI data. A new MIDI list editor allows note-by-note editing. Imagine the list editor as a large Excel spreadsheet, with each cell representing a piece of MIDI data. This is a very handy and powerful addition if you are using MIDI with Acid Pro 4.0. Other sparkling new MIDI options include routing tracks to a VST instrument and support for Yamaha’s new Open Plug-In Technology (OPT). Also, you’re now able to route your MIDI track to a soft synth.

In addition, Acid Pro features some new interface and performance improvements. You now can select multiple loops and preview them in sequence. Also, set default track properties, such as volume, pan, and height, for all new tracks created. The Acid audio engine has been improved. Extra processing power yields even better playback performance.

As for video, you can now add Windows Media Audio and Windows Media Video directly into your Acid project. Also the video playback window has been improved, offering display compensation for non-square pixel aspect ratios. Since Acid Pro 4.0 can import a video track, you can easily create a soundtrack for any scene, export the track as a WAV, and bring it right into your NLE. Having used video in previous versions of Acid Pro, the video in 4.0 looks great, plays excellently, and the aspect ratio correction really helps. Ideally I would like to see NLE project file import (such as Premiere and Avid) so I could bring in my whole movie. Put this on the wish list.

This update is not mission-critical for casual users. Most of the new features in 4.0 are on the high end and may not be useful to novices. However, professional users will find this to be one of the most robust updates ever, so upgrading is highly recommended. If you are new to Acid, give 4.0 a try. You may find that you can piece together a royalty-free soundtrack for your next video production quite easily.

It’s worth noting that the extensive loop collections available from Sonic Foundry cover every base. Many tailored to scoring video and film are worth checking out. Aside from the professional features, powerhouse output, and nice-and-easy learning curve, Acid Pro 4.0 just happens to be one of the most fun programs around. Once you lay down some tracks, trust me, you’ll be hooked.


Company: Sonic Foundry Madison, Wis.; (608) 256-3133

Product: Acid Pro 4.0

Assets: Powerful new 5.1 surround tools; extended automation via track envelopes; several new MIDI tools; improved video playback.

Demographic: Any professional looking to score a video production in an easy, royalty-free manner.

Price: $499.95


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