Learn from listening, that’s the most basic principle in a musical education: listen. Knowing how each instrument sounds is imperative to orchestration. As you listen to recordings, start identifying what instruments you hear. On a basic level get the sounds split into the major instrument families, is it a wind? is it a string? From there, determine the pitch range and further analyze the tone to identify it. Non-musicians sometimes will process the sound they hear as one group entity, not really distinguishing individual instruments, if you tend to listen to music this way then you must change your whole viewpoint. It comes with the price of lost innocence though, but I don’t think you’ll regret crossing that threshold. There is a lot of value to searching out solo performance videos on youtube where you can see a player and hear the isolated sound, do this for any type of instrument you need to get more familiar with. Then go back to ensemble recordings and try to zero in on those sounds and how they interact with the whole. Watching videos of live orchestral performances is great too, especially when they have multiple close camera angles to highlight the sections.
An instrument up close and solo will have a different sound than when mixed in with a group in a large reverberant room, so be aware of that. Mic placement and room acoustics have a big effect so you’ll notice instruments sounding quite different because of those things. I like to listen to classical radio as I drive and identify the instruments and analyze how they are utilized, you’ll want to get to the point where you can do this without any visual cues (like a video zooming in on a bassoon player when the bassoon has a solo). Some instruments will stand out easily like many percussion instruments or the bright oboe tone over quiet low strings, but the more instruments are playing at once the harder it gets to hear things like a clarinet or flute in a middle harmony note. The highest and lowest pitches are easier to pick out of the crowd, especially the highest note. If it’s just one instrument group on the high note like 1st violins soaring, or a lone piccolo then that is fairly easy to process, it cuts through the mix as they say.
A common stereo image will have violins on the left, cello on the right and so on according to how the seating is in the orchestra. You can use this as a clue as you are listening to hear where the sound is coming from connected with what instruments you expect to be sitting in that area. But of course seating arrangements can be modified and sound engineers do different things so don’t rely on this, it’s best to get it just from the tone but it’s an extra clue you might use if you get stumped. Usually viola will not be overly heavy in the left channel, so if you are trying to distinguish between low violin and viola then it might come in handy to remember that violins are more heavy on the left side. There are tonal differences between violin in the low range and the corresponding viola notes but it’s pretty subtle, they can sound really similar and I can easily be fooled.
Brass is difficult to distinguish too when all playing together, there is that brassy blend and I wish I was better at being able to pick out just what notes the horn is playing as opposed to trombone or trumpet, although trumpet usually has a nice brilliance which is distinguishable from the more rotund stately sound of the horn. When it all blends together and the sections play divisi it’s quite a trick. You get doubling going on too, like cello and bass together, or cello and bassoon, or clarinets and violins etc. This has an effect of richening or fattening the tone but it’s very difficult to identify exactly how it’s scored in many cases, you may hear just the cello and not realize there is a wind doubling, or you may think it’s a bass clarinet double when it’s actually a bassoon. This is my experience.
I don’t expect anybody (except for some very exceptional genius) to be able to just listen to an orchestra and be able to accurately replicate the score note for note by ear. That would be so amazing, but I would expect a good orchestrator to be able to come up with a close approximation. This should be a goal. So to do this you not only need to identify what instruments are playing the parts but you need to be good enough at ear training that you can transcribe the correct notes and rhythms too, that’s a separate skill in itself that applies to any instrument or ensemble, not just orchestras so that should be something all musicians develop.
Once you are at a point where you can usually identify the instruments by ear when they are playing exposed parts then it’s a good idea to move to the next step which is to cheat and look at the answer key while you listen. The answer key of course is the conductor’s score, it will tell you exactly if you are hearing cello and bassoon together or if it’s just cello alone. I think it’s good exercise to try for a while first without looking at the score but then to advance your skills you really need to start score reading while listening. As you read the tutti sections, where everyone is playing, you can see all the details of who is doubling who and how those inner harmonies are filled. You’ll probably find some wind parts supporting the harmony in there that were not immediately apparent to the ear upon first listen and other hidden tidbits that you can dissect and analyze for years to come. What fun we have in store. I’ll pick up with score reading in the next post.