(NOTE: Two MP3 links at the bottom of the post - A live clarinet track, and a MIDI emulation of it.)
A bit of MIDI theory that made a big impression on me back in the '80s when I first started using MIDI, was that the MIDI musician should try to emulate the characteristic playing styles musicians use with their various analog instruments.
The means by which to accomplish that kind of emulative playing was more limited back then, but now with the preponderance of sampled instruments being used, and with digital recording more sophisticated than ever, we can more successfully play our virtual instruments "characteristically."
Having a good sample set of a given instrument is only the starting point. If all we do is trigger notes and expect the results to be stellar, we're only doing a fraction of what's possible to make the samples come to life. The most superbly and detailed sample set in the world won't save the listener from a mediocre performance if the MIDI musician doesn't invest some time in massaging those samples and prodding MIDI tracks to come to life.
An important caveat to what I'm talking about is that MIDI driven digital performances will Always be abstractions of what can be played on real world instruments. There's always a simplification, and exaggeration even, of what "real" instruments are capable of. To me, there's a nice trade off: The MIDI abstraction has a unique flavor which is appealing in its own way.
That being said, most people working with MIDI are very concerned about being as "realistic" as possible. My caveat above is to remind everyone that there's a limit to what can be done, and we shouldn't obsess with detail work to the point of thinking we can completely trick the listener into thinking they're hearing live music--we should enjoy and appreciate the way our digital creations are things unto themselves, transcending mere "renderings" (a term that makes me shudder) or "mock ups" (an even more shudder inducing term). I think the best MIDI productions are analogous to a Cubist painting's depiction of natural objects, while compositions played by musicians with traditional instruments are the meticulously "realistic" paintings of the late Renaissance.
Yet, to base our virtual instrument performances on how the real things are played needs to be our starting point as we develop our unique MIDI interpretations of live sound.
Once in awhile we need to refresh our senses with examples of real instruments being played. And when we're working on our projects, it's always helpful to stop and focus especially on examples of the instruments we're using in spotlighted roles.
Using the great GPO Clarinet, here's an example of studying a live Clarinet performance, and playing that virtual instrument "characteristically." By spending a few hours focused only on the Clarinet, and using my imagination as a guide to using my software tools, I felt ready to work with a Clarinet spotlighted on a new piece of music.
--The Main Ingredient in attempting to make a MIDI performance as natural as possible, is the plentiful use of MIDI volume control. With Garritan instruments, we can use either CC1 or CC11 to create the volume part of a MIDI track's performance. CC1 and 11 are interpreted in exactly the same way in ARIA, so use the control that's most convenient with your particular set up. CC7 is Not intended as the control for an instrument's dynamic volume changes. CC7 controls the sliders in ARIA, and the MIDI sliders in our software. With CC7 we can set the Potential volume for instruments, and then should usually leave it alone for the rest of the project. It's CC1 or 11 that we Must use, and in a continuous fashion, on all of our MIDI tracks.
Here are the steps I went through for creating my emulation of a live Clarinet.
--In Sonar, I imported the 49 second demo MP3 of "Santiago Legend" by contemporary composer Howard J. Buss.
--In ARIA's Control window, I turned the Clarinet's Auto legato on for monophonic playback. In the original GPO, instruments were programmed to be monophonic, and that was very helpful to automatically have the instruments playing the way they really do. But in the current GPO, the instruments are polyphonic by default, and the only way to start making soloists sound natural is to turn Auto Legato on so monophonic playing is available. The other option is to edit the polyphony settings in the SFZ files.
--I loaded GPO's Bb Clarinet into ARIA, and chose the Small Chamber Convolution Reverb.
--Also in ARIA's Control window, I turned on the Clarinet's EQ and made some adjustments that I felt made the instrument a little more warm and less brittle. I used the tone of the instrument in the MP3 as a guide.
--In a MIDI track parallel with the MP3, I started playing the piece by ear. I worked in extremely small bits of only a couple notes at a time. I listened to a segment, recorded a few notes, then moved on, listening, recording, and not being concerned when my timing wasn't matching the original. I was just putting together a raw track with notes matching the recording's.
--Next, I hand edited note entrances in the Piano Roll View. Snap-to-grid was turned off so I could move notes to exactly where I wanted them. Playback was start and stop as I worked my way through, getting my MIDI notes to more precisely match the note entrances on the MP3. Having the audio track visible above my PRV gave me a visual guide for this editing, since the onset of notes can clearly be seen in the MP3's waveform.
--Next, I did a volume recording pass over segments of the track, this time working in much larger sections, emulating the volume fluctuations in the live musician's performance.
--In the Piano Roll View again, I hand edited both the volume data and velocities. I needed to bring some sections up where I'd gone down too far in volume, and in a few places I wanted to added extra hills of data. Also during this editing session, I adjusted Velocity values as needed, mostly needing to lower the values of the notes that started passages. I needed a greater number of softer attacks than I'd initially recorded, and lower velocity values makes for softer attacks.
--I recorded another pass, this time with Pitch Bend at the ready. There was one note in particular where the live musician seemed to slide a bit more prominently into a note, so I did a bit of PB into that note, and hand edited the results so the data didn't start before it was meant to.
--EQ AUTOMATION - Here's an extra bit of finessing which can be worth your while on prominent solo tracks. The timbre of Garritan instruments changes a bit as you perform your volume control, but to add an even wider range of timbre control through EQ adds yet another layer of realism. I turned on the EQ section of the audio track connected to ARIA. EQ doesn't effect MIDI, only audio, so I needed to either turn the EQ on in that audio track, or bounce my MIDI track to audio and turn the EQ on in the bounced track.
I activated several of the EQ bands and set them to record automation. Just as with any Sonar control set for automation, all you have to do is play the project, and move the armed controls as the project plays and those moves are recorded. When I was done, I had EQ envelopes for the 3 frequencies I automated, and they were all located on ARIA's audio track. I kept comparing the results with the original MP3, and grabbing the nodes on the envelopes, made some adjustments here and there as needed. My primary goal was to emulate the way the real clarinet's tone gets brighter as the volume is increased and when it goes into the higher octave. Conversely, I emphasized the lower frequencies when the Clarinet was in its lower register. That range of dark to bright is true of most all instruments. The results made the track sound much more like the live original. It was more colorful and organic, less static.
When I was satisfied with my recordings of notes, volume data, EQ automation, and my edits of all that, I exported a 32 bit master
In Sound Forge, I opened up my recording and also the original MP3. Looking at the waveforms side by side, I could see a few places where I could better match some of the volumes, so by following that visual guide, I made the necessary adjustments.
If this was my own composition, I would be satisfied that I'd done a good job of playing the Clarinet in a characteristic way. With all of that fresh in my mind, I was ready to work on my own project's Clarinet track.
Original live recording of the "Santiago Legend" segment
My MIDI version of the same segment
Going through that kind of process is a very well worthwhile few hours to spend now and then to get yourself more up to speed to making the most out of your Garritan instruments.