There are two types of synthesizer that you'd look to if you wanted to recreate a realistic orchestral performance - sample-based synthesizers, and physical modelling synthesizers.
Sample-based synthesizers (and sample libraries)
actually 'cheat', in that they actually contain recordings of real players playing the different instruments - with a high quality library containing a large number of techniques played on that instrument.
So how close you can get to an orchestral sound depends on how extensive your sample library is, and your knowledge of the library and how to use it.
Even with a very extensive library, it might be that some instrumental lines - especially in prominent solos - are, in practical terms, easier and cheaper to record using a real soloist if a realistic sound is what you want.
Physical modelling synthesizers are a mathematical model of the physical behaviour of a real instrument.
Some of them are starting to get very good.
However, it is not necessarily easy to get them to respond in the way you want -
a lot of detailed control information is probably needed, such that creating a realistic line may, again, be harder in some cases than getting a real player to play the line for you.
So in summary - you can probably get close to a real orchestral performance with synthesizers, but getting really close would require so much effort that it might not save you any time or money over using a real orchestra.
Synth manufacturers have, for the most part, been happy to focus on what synths do well rather than really make the effort to put orchestral musicians on the street...
music.stackexchange.com/users/18896/topo Reinstate Monica
Computerized reproduction of orchestral music gets better all the time, and whether it's good enough for some purpose depends on the purpose.
I would say that the percentage of needs where a software-based automatic interpretation is "good enough", increases all the time, at the same time as the general public (i.e. audience) gets more and more used to all sorts of artificial sound.
Here's an example of Note Performer 3 by Wallander Instruments playing a Star Wars score notated in the Sibelius notation application.
Good enough for ... something?
The main idea with Note Performer is that in combination with a score-writing program it interprets traditional musical notation into a performance, rather than relying on a "programmer" musician doing the translation and feeding it low-level geek-oriented MIDI data.
Because Note Performer is driven by higher-level notation symbols like hairpins and slurs from a notation program like Sibelius, Finale or Dorico, it knows (or tries to reverse-engineer) a bigger picture.
I'm not sure (after looking at the PDF manual) at which software layer the interpretation from symbols to data happens in each case, but
anyway, Note Performer constructs a fluid continuous flow of expression, controlled by musical symbols.
(And it needs a one-second delay for doing this)
With traditional sequencers and sample libraries, everything needs to be "programmed" in terms of, say, note velocity numbers, key switches, control changes and program changes, which end up triggering samples and switching or cross-fading between sampled notes.
Wallander's synthesis engine is not based on entire sampled notes, but a "component-sampling + acoustic behaviour modeling" approach where each instrument's sound has been sampled as small components that are used to construct the whole sound in an additive fashion, guided by complicated behavioral instrument models which decide how much of which components are needed in order to produce the requested notes and pitches with the requested expression parameters.
I'd say it's more of a synthesizer, definitely not a sampler.
And it's not based on physical component modeling either.
music.stackexchange.com/users/51766/piiperi Reinstate Monica
My answer is no.
At least for now.
Let's compare with a professional symphony orchestra.
All players have played their instruments full time at least 5 years, often up to 45 years.
The requirements are brutal, you could compare with the top teams in NHL ice hockey or perhaps Harlem Globetrotters.
Before these at least five years, most players started in "minor leagues" some 10 to 15 years, often starting playing from five years old.
The orchestral instruments has often been developed over a long time.
I play the bassoon and the instrument went through a long development period, starting somewhere in the 17th century, accelerating in the 19th century and still ongoing.
(To be very clear, I am an amateur player and the pros are far, far, far ahead of me).
Synths can come close in sound and expression, but there are few players that can use the full potential of expression.
I believe that over time, a few players will reach high levels, and with time smarter programs (AI) can move the field forward.
But, alas, I really can see that in the near future (but that is me).
But in playing other types of sounds or music, the classical instruments fall short.
The palette of sounds is much larger for synths.
My five cents....
music.stackexchange.com/users/45187/ghellquist
There are some high end sound modules and synths that have multiple pristine samples for every note every orchestral instrument can play.
The problem to me would be intonation, how to play a keyboard
so it sounds like I am blowing a french horn.
But I think a skilled player with an aftertouch enabled keyboard might do a pretty good job with some diligence.
music.stackexchange.com/users/48490/user48490
It can get pretty darn close!
And, although a convincing rendition requires a lot of skill, it's probably nowhere near the amount of skill each member of a live orchestra has to bring to the job.
Depressing, isn't it?
music.stackexchange.com/users/17003/Laurence Payne
Vienna Symphonic Library https://www.vsl.co.at/en/Music/MusicBrowse
Unless I misunderstand what those audio samples are, or the company is faking it, they offer a sample of famous orchestral works, performed on their virtual symphony.
Listen to
The Rites of Spring
, it's absolutely impossible to tell that it wasn't a "real" orchestra.
I put "real" in quotes to point out these are extremely detailed, digital sample libraries of real instruments.
Get ready to shell out big money, these products are not cheap!
The full library is $14,000 US!!!
Also, I'm sure the learning curve to using these virtual orchestra - to sound very realistic - is steep.
music.stackexchange.com/users/23919/Michael Curtis
To what degree can technically demanding scores such as Tom and Jerry's (Scott Bradley's music) be performed on synthesizers? Which specific synthesizers are capable of the best quality performance?  I'm a layman, so if my question is wrong or embarrassing. I apologize in advance.  Thank you.
Can synthesizers match orchestras in terms of complexity and quality?
music.stackexchange.com
<synthesizer><orchestra><orchestration>
music.stackexchange.com/questions/79088
music.stackexchange.com/users/56989/Elliot
How close a synthesizer can get to an orchestral sound depends on how extensive the sample library is, and your knowledge of the library and how to use it.  Even with a very extensive library, it might be that some instrumental lines - especially in prominent solos - are, in practical terms, easier and cheaper to record using a real soloist if a realistic sound is what you want.  Physical modelling synthesizers are a mathematical model of the physical behaviour of a real instrument. Computerized reproduction of orchestral music gets better all the time, and whether it's good enough for some purpose depends on the purpose. There are some high end sound modules and synths that have multiple pristine samples for every note every orchestral instrument can play. Instrumental lines are easier and cheaper to record using a real soloist if a realistic sound is what you want.
Instrumental lines are easier and cheaper to record using a real soloist if a realistic sound is what you want. Some high end sound modules and synths have multiple pristine samples for every note every instrument can play. Physical modelling synthesizers are a mathematical model of the physical behaviour of a real instrument. Computerized reproduction of orchestral music gets better all the time, and whether it's good enough for some purpose depends on the purpose.