Let us consider this piece - how could this have been made without multi-tracking?
This piece of Bach is actually 10 tracks overlayed. The harpsichord is two hands, each with 4 tracks. The flute is two tracks. The whole piece was 'played' with Sonic Field controlling the midi to correctly distribute the midi notes in sequence to record all 10 tracks. I then overlayed them in Audacity.
Now - is this cheating? Should I have played this real time. Well yes and no. It would be lovely to do so but also impossible as the flute and keyboard just are two hard for one person to play simultaneously (well - most people anyhow). But, even putting that to one side, the kit involved would be stupid. The sound for the harpsichord required this signal chain:
Waldorf Pulse 2 -> Electro Harmonic Ploy Chorus -> Alter Ego X4 Delay -> Bheringer Sonic Exciter
Now, we might say we could use 8 Waldorf Pulse 2 synthesizers. That alone is just daft (at £360 each - say $600). Nevertheless, there are good polysynth's out there for a lot less than £2880 (e.g. the prophet 08). But that is assuming that we can pass the output through the other components and get the same effect; the truth is that we cannot. The key to the sound is the overlay of the polychorus and delays. The sound would be much, much thinner if all 8 passed voices through the same effects chain. Note even the Sonic Exciter is actually an envelop following device in the drive circuit. That means it would be much less responsive if processing all 8 voices at once. Further still, I use different setting for the left and right 'hand' voices.
So - in reality we would require 8 of everything to mimic the sound of the harpsichord. The flute uses a reverb rather than a delay, so we will need Electro Harmonix Cathederal pedals plus two more of the other synth' and exciters:
2 Reverb (EHX Cathederal)
10 Sonic Exciters
Then we would also need a good mixer!
I guess we are looking at over £10 000 or $15 000.
Seriously - multi-trakcing is not cheating - it is a way bring creating music into reach of a hobbyist!