Logic Notes

v5.3 update; Sample Organisation for EXS24

Published in SOS November 2002
Printer-friendly version

Technique : Logic Notes

Logic has finally made the transition to Mac OS X, but does the overall improvement in performance make up for the dropping of VST support? Plus, there's a look at the new v5.3 update, some advice on sample organisation for EXS24 users, and more of those handy tips.

Having been first shown at the Macworld show in New York over a year ago, Emagic released the so-called Logic System for Mac OS X at the beginning of September, making it available as a free download for licensed XSKey Macintosh users. The Logic System basically consists of Logic Platinum 5.3 and drivers for Emagic's range of audio and MIDI devices, including the EMI2|6, MT4, Unitor8 and AMT8. Perhaps best of all, because Emagic's plug-ins are built into the Logic application itself, the full range of virtual instruments and effects, including the EXS24, ES2, EVOC20 and so on, are all working fine in this first Mac OS X Logic release.

Logic for Mac OS X fully supports Core Audio (OS X's audio architecture) and, because this is capable of low-latency, multi-channel operation at high resolutions and sampling rates, it means that previous standards for getting professional-level audio into and out of the computer under Mac OS 9, like Steinberg's ASIO and Emagic's own EASI, are no longer required. In fact, the Audio Driver Preferences window now looks particularly empty, although support for Roland's VS range of recorders has remained. One of most useful features of Core Audio is that you can configure the buffer size (and therefore the amount of latency) within Logic, even if you're just using the built-in audio facilities of your Mac. The buffer size can be set from 2048 samples right down to 64 samples via the I/O Buffer Size pop-up menu, giving latencies from 46ms to 1.5ms respectively.

My first tests with Logic on Mac OS X were carried out with a 700MHz iBook, which only had a 128MB RAM. Under OS 9, there wasn't even enough memory for Logic to run the audio engine, but under OS X I was able to run Logic and play the 'ES' demo song with a latency of 1.5ms! I found this pretty amazing, and it certainly corroborates Apple's claims regarding the superior memory management in OS X, especially in the handling of virtual memory. But another area where Mac OS X offers improvements is in its full support of multiple processors, and users with dual-processor Macs have reported huge performance improvements when using the OS X version of Logic. I read one user claiming that a song that previously overloaded his system now only required about 50 percent of the available processor resources, for example.

MIDI is now taken care of with Mac OS X's Core MIDI, and anyone not using an Emagic MIDI interface will be dancing in the street at the prospect of not having to worry about OMS any more. After installing the beta OS X drivers for an M-Audio Keystation 61 USB MIDI keyboard, it was automatically available to Logic without any further configuration, and playing Logic's instruments in real time was absolutely no problem. Core Audio and Core MIDI make it possible to have a complete mobile composition tool with either an iBook or PowerBook running Logic and OS X. The latency is now low enough to use the built-in headphone output seriously (at least for writing), and USB MIDI keyboards are absolutely ideal for making music on the go since they require no additional connections, MIDI interfaces or power sources. While this has been possible to a degree with OS 9 for sometime, OS X simplifies the process and gives you the kind of audio performance that previously required additional hardware.

The most significant change to Logic on Mac OS X is that Emagic have decided to drop support for VST plug-ins and focus instead on promoting and supporting Audio Units, OS X's own audio plug-in format, which has been developed by a team at Apple. Inevitably, this has created quite a stir amongst Logic users on the Internet, but the decision may prove beneficial in the long term. The Audio Units format is effectively OS X's equivalent of Windows' DirectX plug-in standard, providing a platform so that any developer can easily write audio plug-ins or offer the support in host applications to run them. This will hopefully lead to a situation where every OS X audio application offers support for Audio Units, meaning that developers only have to write one Mac plug-in, rather than support the multiple platforms that exist on OS 9 at the moment, such as MAS, VST, RTAS and so on.

Now that Logic supports Core Audio, the Audio Driver Preferences dialogue seems rather empty, all of a sudden...

Even if you currently were using VST plug-ins with Logic on Mac OS 9, these wouldn't have worked with Logic on OS X even if Emagic had implemented support for VST plug-ins. As many users are already aware, VST plug-ins need to be Carbonised to work within VST hosts on OS X, so Emagic are hoping that, since VST plug-ins need to be tweaked for OS X anyway, developers might as well tweak their plug-ins to work as Audio Units so they'll work in a wider range of applications. The Audio Units standard is an open one, and the SDK (software development kit), which provides the information for developers writing both plug-ins and hosts, has been available from Apple's web site for some time. However, Emagic have announced an additional library to make it easy for developers to port their existing VST plug-ins into Audio Units, which should be available shortly.

The only stumbling block is that, while Logic is now Mac-only, programs like Cubase SX and Nuendo remain cross-platform, so it's still useful for a cross-platform plug-in standard like VST to exist from a developer's perspective. The likely scenario is that major developers will support Audio Units, in addition to the VST standard, and some clever person will program a 'wrapper' capable of running Carbonised VST plug-ins within an Audio Units host like Logic. Although the initial release version of Logic for Mac OS X doesn't actually support Audio Units, a beta version offering this facility was being made available to developers at the time of writing. And most major developers are already rumoured to be working on making their products available in this new plug-in format.

Aside from the 'under the bonnet' changes, Logic Platinum for Mac OS X is basically the same as Logic Platinum for Mac OS 9, or even Windows. The interface elements such as menus, tickboxes, file selectors and so on, all take the Aqua appearance, and, in line with the OS X user interface guidelines, the Preferences menu item has been moved to the Logic application menu. But other than this the main visual elements remain exactly the same, although Logic v5's interface had already showed signs of being Aqua-inspired before the OS X release.

Unfortunately, not every feature from the OS 9 version has made it into the OS X version of Logic in this first release. Notable absences, as mentioned on Emagic's web site, are Rewire and REX-file support, plus the ability to import and export OMF files, though it's claimed that the inclusion of these features is planned for a future release, depending on "external developments". Why this should be the case is currently unknown, especially as Steinberg already have Cubase SX running with Reason via Rewire on OS X, as discussed in last month's Cubase Notes. In addition, DAE support is also not available, but this is a feature that's dependent upon Digidesign's own support for OS X, and there may have been announcements made on this subject by the time you read this column.

However, I don't want to round off this column by focusing on what Logic for OS X doesn't have, because I think Logic users will absolutely love the combination of Logic running on OS X. The lack of third-party products may prevent some people from switching to OS X just yet, but the fact that all of Emagic's effects and instruments are provided means you do at least have a full production system available to some extent. If your Mac is running OS X, you can download Logic Platinum for OS X from Emagic's web site at: www.emagic.de/ english/support/download/lpx.html. Although Emagic recommend you run either Mac OS 10.1.5 or Jaguar (10.2), it's actually possible to get by with earlier versions, such as 10.1.4. But with improved MIDI and audio being just one of Jaguar's highlights, it's probably worth upgrading to the latest version of Mac OS X if you intend to make serious use of Logic on the OS X platform.

Logic Tips     As of Logic v5, there are new Key Commands for toggling the various windows, in addition to the old Key Commands for opening them. Toggling windows can maximize your use of limited screen real estate while minimising the need to change screensets. Len Sasso When you want to quickly separate the parts of a multi-part sequence, first open the sequence in any of the note editors (Matrix, Event, or Score), select all the notes, and choose Lines To Channels from the Note Events submenu of the editor's Functions menu. Next select the sequence in the Arrange window and choose Demix By Event Channel from the Split/Demix submenu of the Functions menu in the Arrange window. Boom, you've got separate sequences for each part. Len Sasso When Akai samples are imported into the EXS24, you can choose a level of attenuation to provide adequate headroom when multiple sounds are likely to be played back at high velocity. The default setting suggests -3dB for drum sounds, and I find that also works fine for most things providing you don't layer lots of high-velocity sounds, in which case -6dB may be more sensible. It is possible to select no attenuation at all, but this could cause problems with clipping and so is best avoided. Paul White Once you've sliced your audio file into regions either manually or using Logic's Strip Silence feature, you can turn those regions into separate audio files in one go by selecting them and choosing Save Region(s) As from the File menu of the Audio window. Len Sasso When you want to process notes based on their pitch, consider using the Environment's Mapped Instrument. That allows you to assign a specific MIDI Channel and output cable to each MIDI Note number (i.e. pitch). You could, for example, cable different pitch zones to different MIDI instruments or channel them to different presets in the same multi-channel MIDI instrument. Len Sasso