[gtrdave]

Originally Posted by 10isfreak

I'm pretty sure there is no such thing as "the key of (n) melodic minor." You can have something based on the melodic minor scale, but because the scale is different whether ascending or descending, it can't be a "key." Cursed technicalities.

True.
The theme song to "The Simpsons" tv show is in the key of C, but the main melody is based on C lydian scale. The song is not in "C lydian key", though, it's just in C and sharps/flats are noted on the staves as necessary.

[RockManDan]

the whole point of modes is really just like a subset of keys in my opinion. Keys are really what determine the whole shebang, as we have already discussed. the use of modes is basically like saying ok im playing C major. I got it, but In this particular bar, the chord im playing over is the ii chord, or Dminor, therefore the mode im playing is D dorian. It doesnt change the key or the scale, but the name changes depending on what tonality is happening at this particular moment. Key is about the whole context, mode is about the moment, if that makes any sense.

A great example, as im sure GutiarDave will know, is Satriani's 'Flying in a Blue Dream'. That song pretty much has C as its bass line the whole song, but since the melodic structure includes F# notes and Dmaj chords (see the opening riffs), the key of the song is actually G, if we follow classical music theory rules. However, since the structure of that song clearly says to the listener 'i am centered around C' we have to accept that C mixolydian or whatever mode it is, is really for all intents and purposes the key of the song. Its a classic example of Satriani' pitch axis technique. SO you see that really keys modes they are all tools used to describe how we hear sounds. Sometimes how something SHOULD be named in theory doesnt fit with what it sounds like to our ears, so I find its not wise to get hung up on it too much. These rules are made to be broken in creative ways. Otherwise we've pretty much been out of luck since Beethoven and Wagner. By the time the mid-20th century had rolled around, people had pretty much exhausted the melodies of basic diatonic scales. We had to do something new. Some came up with crazy new theories like serialism and atonality. THe other direction was new sounds, like electric gutiars and drumsets and the like.

[Nate]

Originally Posted by RockManDan

By the time the mid-20th century had rolled around, people had pretty much exhausted the melodies of basic diatonic scales.

That's pretty much a ludicrous claim.

Even if we define "melody" as just enough notes to set one line of iambic pentameter to song [that'd be ten notes] and confine ourselves to one octave alone, the number of possible diatonic melodies is 8 ^ 10, which is well over a billion distinct melodies.

And that's ignoring the fact that we can use a great variety of accidentals, note durations, added octaves, multi-section phrases, etc. Even if we were to grant that a melody shouldn't skip around randomly through the diatonic scale, the number of pleasing-sounding melodies generateable with the simple tools of diatonic scales [we'll leave out chromaticism entirely], rhythmic variation [heck, let's even leave out dotted notes and allow ourselves only the breve, semi-breve, minim, and crotchet], and larger forms [say, a 4-line stanza of iambic pentameter], we'd end up with millions upon millions of possibilities.

Start on the tonic, then progress by step or skip of a third [allowing ourselves only one melodic "leap" for interest] for four lines of ten notes, then return to the tonic, allowing for notes to vary rhythmically among four possible durations:

Something like: 1 * ( 5 ^ 9 [9 notes in a row of one step or skip up or down] * 7 [our one melodic leap] ) * 4 [we can have four such melodic lines] * 4 [each note can have four rhythmic values] = ~219 million melodies.

[actually, I just completely botched that math... much of the multiplication would actually be exponentiation, giving an astronomically large number, in the order of magnitude of billions of billions]

Let's presume that there are roughly 100 million songs that were written during the second millennium [roughly the frame of time the diatonic scale ruled alone]. Now, let's imagine what kind of musical material we'd need to have, at the the turn of the 20th century [near the end of that second millennium] to have truly "exhausted" the possibilities [assuming, of course, that every song had a different melody].

Let's say a "melody" could contain only 4 notes [any of which with equal probability], and each note could only take 4 rhythmic values. That gives us 16 possible options at each point in our melody.

How many notes would we need to have 100 million possible melodies? That is, how many notes long would a "melody" be? Would we need to be composing symphonies or folk songs before exhausting our possibilities?

Turns out we'd need somewhere between 6 or 7 notes to a melody [remember, each of which can only contain 4 different notes and 4 different rhythmic values] to generate 100 million melodies.

Even the simplest of musical systems [pitch + timing] turns out to be virtually infinitely combinatorial.

Even a morse code binary system of either "short" or "long" notes, that could take either pitch "a" or pitch "b" would give us over a million distinct melodies after just 10 notes [only four possible "notes"]!

[RockManDan]

Oh most definitely. I was merely being facetious. Of course there is new music to be written. I love writing music all the time. What i was getting at is that since the mid-20th century, we havent really made any bold strides in new WAYS to write in simply diatonic music, so we innovated in other areas, rhthym, sounds, tones, etc. Beethoven and the like could never have conceived of how pop music sounds today, because he didnt have a concept of drum machines or autotune or any of that stuff. THey couldnt have conceived of the kind of tones that the electric guitar can coax, but one thing they DID do what pretty much exhaust most if not all of the probable chord progressions possible using the standard tonal harmony rules. tahts all i was getting at. You are correct of course that there will always be new music to write, even if we're not coming up with new progressions. theres still a lot of life left in just I IV V, not to mention countless others. thats the exciting part.