I'm just wondering what the point is of synth instruments (manipulating waveforms) if I can just use samples for everything. For example, say I sample a single middle-c piano note. My understanding is that a DAW sampler can then change the pitches of this one sample so I could potentially get all the notes across the piano from just this one sample. Similarly I could use samples for all harmony, beats, and melodies across all instruments. So could my entire song be made of samples, why use synth instruments then?
Can a song be made entirely of samples?
For example, say I sample a single middle-c piano note. My understanding is that a DAW sampler can then change the pitches of this one sample so I could potentially get all the notes across the piano from just this one sample.
So far, you're right to an extent - simplistically-speaking, the piano is one of the instruments that can be reproduced quite accurately* with samples. However, it can't be done at all accurately by sampling a single middle-C note and repitching that one note. This is because the way the timbre of each note evolves is very different at different points on the keyboard - and also different when the note is struck at different velocities. So a convincing piano multisample will need to consist of at least dozens, and probably hundreds, of individual samples. This can take hundreds of megabytes, or even a number of gigabytes, of RAM to store - which is one of the drawbacks of sample-based synthesis.
(*And even then, some aspects of the sound of a real piano come from the way the different strings resonate with each other - which would possibly take even more samples, plus some clever programming, to emulate).
Similarly I could use samples for all harmony, beats, and melodies across all instruments.
Well, all instruments is where it gets really tricky.
Let's step away from music for a minute and imagine that you want to make a sampled version of your own human voice. You could just record yourself saying each word in the dictionary, and then construct any phrase, perfectly realistically, out of that, right?
Well, of course you couldn't - the way humans use their voice, they never quite say the same word twice - it depends on the way they are expressing and intoning the sentence due to the meaning and context, how it joins on to the words that come before and after, the emotions, how tired you are... there's a lot of variation.
Now something like a violin perhaps doesn't quite have as many input parameters as the human voice does - but there are still all sorts of ways of bowing, articulating notes and joining each note to the next - so many so that building a truly realistic sample-based instrument and programming the ways the samples were selected would be an incredibly complex proposition. A synthesized physical model of a violin would have the advantage here.
And of course - you can only sample instruments that exist. One of the great things about synthesizers is that they can create sounds that couldn't exist acoustically.
why use synth instruments then?
- Because they don't use oodles of memory
- because they can be programmed to react to multiple, constantly-changing parameters much more easily
- because they can create sounds that can't easily be created acoustically
Having said all that - there isn't necessarily an abrupt line separating sample-based instruments and synth instruments. Many sample playback instruments are "sample + synthesis" - providing some extra processing on top of the basic sample playback - and many 'pure' synths still make use of some basic wavetables which are played back much as a recorded sample would be.
I think you have a number of issue combined in this question.
But about the piano sample using only middle C, you could do this but when the single sample is pitch shifted through the full piano range it will not have the right timbre.
Really good sample libraries use sample from the full range of an instrument as well as different dynamics. Really good sampling gets articulations too. Like for a violin different bowing techniques.
On the general question, can a whole song be all samples? In part I think that happens with recordings now. Drums, guitar, bass patterns can all be samples. Some parts will be from performance like vocal, or synth. Perhaps there aren't a lot of records that are 100% sampled, but I don't think there is a technical limitation. Voice is the obvious problem if you wanted to have actual text sung rather than just 'oooh' and 'aaah.'
I'm not sure if this is part of your question, but using samples doesn't necessarily mean using sequencers. I set up an old midi keyboard into a DAW, found some excellent soundfonts for various instruments and then recorded performances using those sampled soundfonts. I didn't sequence the parts.
Yes, we can make music with only sampled sounds. And we do. If we're trying to imitate 'real' instruments, it's almost exclusively what we do.
There'll be more than one base sample for each instrument though. You can only shift the pitch so far before the sound becomes unreal (remember 'Pinky & Perky or the Munchkins?) A good sample set has a new base sample for every few notes. An ultimate piano sample set might sample EVERY note, and sample it several times, at different dynamic levels.
Why also use synthesis? Well, we've stopped kidding ourselves that synthesised instruments are perfect imitations of real ones (we continue to kid ourselves that sampled ones are though :-) But we still use the characteristic sounds that synthesised sound CAN deliver. It isn't ALL about imitating orchestral and rock instruments. Sometimes a MiniMoog is the sound we want. (And yes, sometimes we make do with a sample of it :-) )
I'm just wondering what the point is of synth instruments (manipulating waveforms) if I can just use samples for everything.
Synthesizers don't usually make convincing substitutions for acoustic instruments and samples of synthesizers certainly exist, so you've asked a reasonable question. But samplers haven't subsumed all of synthesis and I doubt they ever will.
As originally conceived, synthesizers generate their own waveforms from scratch. It's this property that gives the synthesizer its name. Samplers, on the other hand, essentially play back a recorded sound.
We now also have synthesizers that use sample playback as the basis of waveform generation. It was new technology in the late 80s and early 90s. Instruments like the Roland D-50 and Korg M1 blurred the lines between synthesis and sample playback.
There is more to synthesis than just generating a waveform, of course. Waveforms are shaped with the amplifier and filter components of a synthesizer and further modified with LFOs, effects, etc. If you didn't have these things available to you, you could not create new sounds, and creating new sounds is the real point of using a synthesizer. Over the decades, synthesizers have been applied to the problem of reproducing the timbre of acoustic instruments, which they can occasionally do with limited success. Samplers are better at that particular problem, but also have significant limitations. (Mathematically modeling how acoustic instruments produce sound is the next technology. It has taken over sampling as the state-of-the-art in the development of digital pianos, for example.)
My understanding is that a DAW sampler can then change the pitches of this one sample so I could potentially get all the notes across the piano from just this one sample.
The timbre of an instrument changes when the musician alters the pitch and dynamics. Pitch shifting can't recreate that, so many samples are required to make a sampled instrument sound anything like the genuine article.
For example, on an acoustic piano, C4 has a different timbre from E6. Pitch shifting C4 up by a major 17th doesn't recreate that timbre. But that's not the only problem. The act of pitch shifting itself introduces timbre changes which are exacerbated as intervals get wider. Listen to this example:
You hear three sounds:
- A piano, sampled and played back at C4.
- The same sample, pitch-shifted to E6.
- E6 resampled and played back at C4.
It's not even recognizable as piano!
I could use samples for all harmony, beats, and melodies across all instruments.
Why use synth instruments then?
The most compelling reason to use a synthesizer is the same as it ever was: to make new sounds.
musique concrète Some one did that in the 50s and in the 60s. They actually spliced open reel tapes and replayed the pieces. Ant this was made to manipulate the sound to obtain new and weird sounds. Absolute Genius made an episod showing that using a DAW and samples is way easier to use razor blades and greasy pencils if one likes to obtain new sounds staring to concrete ones.
Clearly an acoustic instruments has precise characteristic that are varying in the way they sound dependant on pitch, loudness and even the other notes played. Also a synts could have easily variable timbre based on note, velocity and time. A digital instruments like a DX-7 couldn't be replicated simply with samples only. You can have sampling based synthesiser where the oscillator are reproducing sampled pieces and are further processed.