SONY Acid Pro 6.0b (Win)

Every manufacturer of high-profile music software is on the upgrade treadmill: each new release of a respected product has to ratchet up the feature list
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FIG. 1: Acid''s main screen includes a file browser and database display (bottom left) and a mixer (bottom right). The lower area can be resized to show more tracks. Note the in-line display of track envelope data and the crossfade between overlapping clips.

Every manufacturer of high-profile music software is on the upgrade treadmill: each new release of a respected product has to ratchet up the feature list and satisfy musicians' lust for power and convenience. Version 4 of Acid had fallen well behind the curve technologically, but that was before Sony bought Sonic Foundry. Acid Pro 5 was a significant improvement, but although I was able to find a number of things to be enthusiastic about in my review of it (see the July 2005 issue of EM, available online at, I still felt a bit lukewarm.

Fast-forward: Acid Pro 6.0b is out, and the enhancements are even more striking. In spite of a few rough edges, Acid is now fully capable of competing with other digital audio sequencers.

Three huge improvements are immediately apparent. First, Acid can now assign two or more different clips to a single track, a feature that every other digital audio sequencer has always had (see Fig. 1). That makes arranging and overdub recording much easier. Second, the MIDI sequencing features have been brought up to a professional level. Third, automation data no longer has to be created using graphical envelopes (though that mode is still available). You can now record automation in real time with the mouse or a control surface. The method for doing so is largely undocumented, however; more on that in a moment.

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Acid's specialty is high-quality time-stretching of loops, and the Acidized WAV file has become an industry standard. Numerous loop libraries are available for Acid, from Sony and elsewhere, and if you want to use a loop that hasn't been Acidized, you can add markers to the audio file within Acid.

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FIG. 2: Acid''s Media Manager makes it easy to find the clips you want. The pop-up window (right) adds checkbox items to the Advanced search criteria field (lower left). Clicking on a tempo field brings up a slider box. Comments and ratings are added by the user.

Acid hosts VST and DLS soft synths and VST and DirectX effects, but not DirectX synths. (Because most Windows plug-ins are available in VST format, this is not a big problem.) You can apply groove-quantization templates to either audio or MIDI, and a generous set of grooves ships with the program. Sony also includes Media Manager, which provides a powerful way to categorize and organize your loop library (see Fig. 2). Acid supports a single video track for soundtrack work and includes a good selection of basic effects, though not all of them are automatable.

When you drag clips around in the tracks, you'll be pleased to find that their automation-envelope data moves with them. Dragging one clip over another automatically crossfades between them, which is very convenient. The contents of a clip can be slipped left or right without moving the boundaries of the clip, allowing you to easily align sampled drums to the time grid.

The new Sectioning utility is quite handy for trying out different arrangements. Sections, which appear as colored labels above the time ruler, can be given names and moved around freely. Sections normally snap to the grid but can be placed anywhere if snapping is disabled. Acid's Chopper utility is ideal for adding fills, stutters, and polyrhythms to sampled drum loops.

Acid Pro 6 has no track-freeze command, no CPU-usage meter, and no MIDI-input meter. These features are standard on most pro-level digital audio sequencers. Sony recommends using Windows Task Manager for monitoring CPU usage, but it occupies a fair chunk of screen real estate, so that is not an ideal solution.

Installation requires serial-number entry and online registration. I had no problems installing Acid on my 3 GHz Pentium 4 PC, and the upgrade from 6.0 to 6.0a was trouble-free. Acid supports dual and multicore processors and is capable of 24-bit, 192 kHz recording and playback. Included in the boxed package is an Acid-specific version of Native Instruments Kompakt, which offers 2 GB of instrument samples. Most of the popular instrument sounds are covered, and Sony is already expanding the Kompakt library with additional sounds that are available to registered owners as free downloads.

Ready, Aim, Mix

All tracks in Acid have their own level and panning sliders in the track-controls column along the left side of the main window. If you're working in 5.1 surround, you'll see a little square speaker diagram instead of a pan slider. You use the diagram to position the track's output. Acid also has a mixer panel, which contains the main output bus, any effects-send or group-send buses you create, and audio-output buses for soft synths and ReWire devices. Soft-synth mixer channels can use insert effects, but because they have no sends, their signal can't be routed into effects or group buses.

When you create the first send bus for a project, each track acquires an extra multipurpose slider for controlling the send levels routed to the various buses. Each bus output for each track can be either pre — or post — volume fader. Prefader sends are not shut off by the track-mute buttons. I feel this is a serious design flaw, but Digidesign Pro Tools operates the same way, so I guess some musicians aren't bothered by it.

Each track in Acid has two independent volume faders, a fact that may not be apparent at first, as they occupy the same screen space and only one is displayed at a time. One fader, which displays a small icon of a gear-toothed wheel, can be automated; the other can't. You can record a level-automation envelope and still use the nonautomatable trim slider to adjust the overall level of the track's output without having to edit the automation envelope. You can also use the Envelope tool to select points on an envelope and move them up or down as a group.

Acid's automation features interact with the track-mute buttons. If a track is set to read automation data of any kind, the track-mute button is disabled. Thus, each time you need to mute or unmute an automated track, an extra mouse-click is required to shut off the automation reading for the track. If the track has a prefader send, a few more clicks will be needed to switch the send temporarily to postfader. To unmute the track, the whole process has to be reversed. This implementation is conceptually clear, but the resulting user interface is needlessly complex.

Not Fade Away

Acid provides templates for controlling parameters on the Mackie Control Universal and the Frontier Designs Tranzport hardware devices. In addition, software hooks allow a generic MIDI controller surface to be used for external control of the mix, including automation recording. I didn't have a Mackie available, so I hooked up my ancient Peavey slider box (don't laugh, it still works) and tried assigning Peavey sliders to Acid's faders.

After hours of frustration and several emails back and forth with Sony's support staff, I finally succeeded in getting Acid to record automation data from my control surface. Among the things the manual doesn't explain is the fact that assigning MIDI data types in the Preferences box to control specific functions isn't enough. The External Control item must also be switched on in the Options menu. Also, wiggling the physical slider won't do anything until it crosses the stored value of the automation envelope. And automation must be switched on for the control surface itself as well as for the individual track. The state of the control surface is never displayed on the computer screen — Acid relies on the surface to have its own data display. Also worth noting: effects parameter envelopes cannot be addressed by the external control surface. (Sony says the Mackie Control Universal fully supports effects control and automation but that generic control surfaces do not.)

MIDI on the March

The expanding world of software synthesizers has made MIDI sequencing a must-have for serious computer-based music production. In contrast with earlier versions, Acid Pro 6 qualifies as a real MIDI sequencer. It provides in-line MIDI editing (see Fig. 3), in which a piano-roll display of notes, Velocities, and other MIDI data appear directly in vertically expanded tracks in the track window.

The switch that displays the MIDI data in piano-roll format is global for Acid, so after recording a number of MIDI tracks, you'll find that you might need to rearrange the window by hand to view the data you want to edit. Acid also has a floating piano-roll edit window, which displays one MIDI clip at a time. This window works fine for quick-fix edits, but its time ruler doesn't show the position of the notes in the project, only their position within the clip.

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FIG. 3: Acid''s in-line MIDI editing shows note Velocities as diamonds on stems and controller data as squares connected by contour lines. Shown here are a mod wheel move (blue) and a couple of pitch bends (light green). You use the sliders in the track header (left) for recording controller data or adding offsets to existing data.

Overdub recording into MIDI tracks is now handled as in other sequencers. Control Change, Aftertouch, and Pitch Bend data can be cut and pasted, edited with a pencil tool, and so on, using the same tools that are used for track-automation envelopes.

I tried a number of plug-in VST synthesizers with Acid, and they all worked well. With multioutput synths, the program lets you add mixer channels only for the outputs you're actually using, a considerate touch that's necessary because Acid is limited to 32 bus channels. (Note that ordinary audio tracks don't require bus channels, so this is not a track-count limit.)

When I first tried using Propellerhead Reason as a ReWire client under Acid, I was dismayed to read in the manual that Acid wouldn't transmit MIDI via ReWire. This turned out to be an error in the manual. MIDI tracks in Acid can indeed send to ReWire clients. Trying to use ReWire with Acid 6.0a consistently crashed my computer, but just before press time I downloaded version 6.0b and verified that the ReWire implementation had been fixed. This will be great news for anyone who likes using Reason and Acid as a team.

Support Hose

A card in the Acid Pro box offers three options for technical support. The Single Solution costs $14.95 and includes support by email only. The Platinum Support Plan entitles you to 180 consecutive days of phone and email support and costs $99.95.

Sony's Web site indicates that purchasers of its pro-level products, including Acid Pro, receive a free Gold Support Plan (60 days, normally $49.95). The time period begins the first time you use the support, so you may want to save up questions for a few days before your first call.

I'm not happy to see a music-software company charging for support. If a company is going to charge for support, however, I feel it's incumbent on them to also provide a thorough, well-written manual so that users who have the patience to read it will be able to resolve most or all problems without having to shell out extra money. The Acid manual, though it's by no means the worst I've seen, fails this test. A number of operational problems I ran into while working on this review are not covered adequately by the manual, and it sometimes skips over important details.

Want to See My Etchings?

When I first installed Acid Pro 6 and looked at the huge improvements in MIDI sequencing and the assignment of multiple clips to audio tracks, I was pumped. When I found that I couldn't use ReWire because of a major bug and couldn't figure out how to make a MIDI control surface work because of the poor documentation, I was worse than frustrated. Ultimately, however, I got the control surface working, and Sony has now fixed the ReWire problem. On balance, Acid Pro is a fine program that's fully capable of meeting the demands of audio professionals.

I'm hoping to see some loose ends tied up in the next revision. The program needs to be able to bus soft-synth channels to aux sends and groups. Track freeze should be implemented for soft synths and audio tracks with CPU-hungry inserts. And if Sony is going to charge for technical support, it needs to provide a much better manual.

Initially, Acid was the only multitrack program that could time-stretch loops. But today, most digital audio sequencers have similar features. With version 6.0b, Sony has taken huge steps toward making Acid competitive.

Jim Aikin has seven digital audio sequencers on his computer (eight if you count Reason) and deeply regrets that he doesn't have time to make music using them all.


Acid Pro 6.0b

digital audio sequencer $399.96 boxed, $374.96 download



PROS: Audio tracks can now contain multiple clips. Full-featured in-line MIDI editing. MIDI overdubbing. Real-time automation recording. Includes NI Kompakt.

CONS: After 60 days, tech support is not free. No sends or effects automation for soft-synth tracks. No track freeze. MIDI control surface implementation is poorly documented.


Sony Media Software