What affects the quality of a digital instrument?

Question

I am a budding musician and I currently am working with cubase. I was wondering what affects the sound quality of certain instruments (setting aside velocity controls, etc). Combined with a good sound card, is it the VST samples that affect the recordings?

I've listened to sountracks from games like Final Fantasy, Tales of, Kingdom Hearts, (etc). It's very obvious that each instrument from each game is distinctly different from the same instrument from another game. My question is what affects this?

Answer 1

This is a huge question, weather or not you realize it. There are so many things that affect sound and our perception of sound that you could spend a lifetime studying and not cover it all.

I included some links below to get you started. Every single component and process in the signal path affects the sound you perceive.

Answer 2

Well, lots of things affect the quality of a digital instrument.

Some of it's the synthesis method... most plug-in synthesizers use digital sampling, which is very good for some things, less for for others. Some of these are very complex... there are Piano sample sets that run into multi-gigabytes in size. The reason for this... they usually include 4 or more samples PER KEY, and of course, 88 keys. The reason for this... when you hit a key hard, the 2 or 3 strings that hammer will strike interact with one another very differently than would a soft touch on that key.

So obviously, a piano made from a single set of samples per key will sound worse (or, perhaps, "less realistic"), and one that's simply invented, using FM Synthesis, may not even sound very piano-like (FM synthesis was made popular on the Yamaha DX7... there are plenty of PC-based synth's that try to recreate that sound... think "80's NuWave").

There are other methods, too... one hot one is called physical synthesis. Rather than record a sound, a physical synthesizer runs a phyiscal model of the things responsible for that sound (strings, reverb, amplifiers, mics, etc).

Some of it's also the number of independent "voices"... you could model a piano key hit with a single synthesizer output, or actually mix together two or three separate synthesized sounds. When you create unusual synth sounds, there can be many different layers of sound that work together to make that note (sound design for music is also an art form).

So basically, yes, the samples you're using in the soft-synth you control over VST are largely responsible for the quality of the sound you hear (assuming it's not a sound reproduction issue, like crappy speakers on the PC or whatever). If you got to a more sophisticated synthesizer (I have a version of Gigasynth, which does have some of those huge piano samples), you might expect a better sound.

Some of it's "post"... in particular, if you're trying to get something that sounds like the music you hear on a CD or in a video game. When you get audio out of a soft-synth, say, for any instrument, it should sound roughly like that instrument, hopefully very much like it. However, that's not necessarily sound you hear in recorded music. If it's a piano, you have to account for the microphone, maybe some EQ (equalization) or compression on it. For a drum, it's likely a different mic (sometimes one per drum), various other things. This is stuff it take years to learn about... if you're really interest in getting into this, look up magazines like "Recording" or "EQ", check out their web sites, etc.

For video game soundtracks, they can use realtime synthesis, but they can also play CD-style recorded music, which can include insanely expensive gear recorded by experienced sound engineers in a professional studio. When they do that, you're right that different instruments sound different... because they probably are. One might have a Seinway piano, another a Yamaha keyboard in piano mode. One guitar might be a Stratocaster through a Fender amp, another might be a Les Paul though a Vox, etc... not to mention the outboard gear used (fuzzbox, reverb, wah, echo, looper, distortion, chorusing, etc).

You CAN get something close(ish) to that class of sound using PC-based tools, but you aren't going to get there starting out. It's very much an art form.

Answer 3

It depends on a few things.  Some VST's are software versions of real instruments (virtual pianos, string orchestras, etc.).  These are all based on recorded samples of the real instrument they emulate.  The quality is affected by such things as the sample rate (the higher, the better sounding, though this will use more of your computer's recources) and the way the instrument was originally recorded.  Also, some VST's have a seperate sample for each note, while others will sample certain notes and "bend" them to correspond with the other notes.  This can lower the quality as well.

Other VST's are synthesizers instead of sample based instruments.  These let you create a sound using different methods of synthesis.  Subtractive is the most common and easiest to understand, though other methods exist as well such as additive, FM, granular, and others.  Each method of synthesis has unique abilities and sound potential that the others lack.