How do you determine what chord the main progression starts on

Question

For example this song

I can't tell if just starts on the A A#dim as a lead in or if Bm G D A A#dim is the actual main progression order

I hope this makes sense

Answer 1

The chord progression starts on the Bm.

The A A#dim is the last bar of the 4 bar progression (assuming a 6/8 time signature, 3 beats each) and since it starts on those chords it is considered a “pickup” bar. A Pickup can be different durations, a bar or a beat or two depending on the song. This song also has a melodic pickup, “I don’t”. The “always” is the beginning of the progression.

Another obvious clue is where the drums come in on the chorus, which is right on the Bm. The chorus uses the same chord progression minus the diminished chord.

Another example of a song that starts instrumentally with a pickup bar is “Whole Lotta Love” by Led Zeppelin.

Answer 2

Where a progression starts is partially uninfluent: what matters is the overall [harmonic] rhythm, which depends on the tonal center of the piece and its "global rhythm".

What you're asking is almost the same as "where does the melody start" (consider "Happy birthay to you": some say that it starts with a rest, while other say that it starts on the "you" word), but usually the concept is more bound to the musical phrase, which is clear from the rhythm, melody and accent of the lyrics (including its meaning!).

It depends on general conventions and it can be open to debate, often depending on the arrangement. In the given song, for example, many would say that the "downbeat" is on the B chord (possibly based on the drums and bass line), while others could contradict that it is on the A chord.

In any case, the phrase starts with the chromatic progression that begins from the A chord, so that is the "real" beginning of the progression.

Answer 3

I see this question as completely analogous to the question "what key is this song in", i.e. how to find the tonic, or how to find where pitch "one" is. In harmony the "one" is the tonic pitch i.e. the home note, but in rhythm it's the first beat of the rhythmic pulse pattern. Just like harmony can sometimes be slightly ambiguous because of lack of asymmetry or some other features (modal harmony comes to mind), rhythm can be ambiguous or misinterpreted as well.

So you're asking, where is the "one" in the rhythmic pattern, and you've identified the following two alternatives.

Alternative 1

Alternative 2

To tell which one is "correct", you have to listen to the rhythmic swaying of the music as a whole, with all instruments and lyrics. To me personally it's blatantly obvious that alternative 2 is the only way to write it and alternative 1 looks ridiculously upside-down, considering what the song sounds like. But to someone else it might not be so obvious.

If you listen to a clock ticking, you won't hear where the 1st second of a minute or an hour is, because all ticks sound the same. But if you listen to this song "ticking", there is a clear pattern where some "ticks" or rhythmic events are heavier than others, and it goes in a pattern of 2 x 4 beats.

The sense of heaviness, which beat is stronger, can be traced down to several features. These can be seen as some sort of transients: changes in frequency content, changes in harmony, changes in instrumentation, changes in timbre.

• Since it's in Bm (or maybe someone would say, its relative major, D major) then Bm and D chords get naturally a bit more weight.
• New musical elements are brought in (or out) so that the transition emphasizes the One a bit more than other beats. (And in the very beginning of the song, this phenomenon makes you assign weight to the A chord, which is why you have the question in the first place. But later on, this is greatly overpowered by weight but on the Bm.)
• The DRUM BEAT and especially the low and punchy KICK DRUM hits on the One. This happens several times in the song. For example at 0:45, when it begins.
• The drum beat STOPS on the One, at 2:44
• The punch words of the lyrics feel emphasized like accent cymbal hits. ...wasted on YOU... Ka ka ka BOOOM... La la la BANG... I dropped the BALL... All of this TIME.

However, it is entirely possible to not hear any of these clues. There are people who simply do not get it. That's why there are different traditions and genres of music. In some genres of dance music there's an extremely loud kick drum going BOOM BOOM BOOM BOOM all the time, and it is actually useful because it allows even the most rhythm deaf person to sense a steady pulse to which they can attempt to move. And in some African/Latin genres, the rhythmic pulse can be so complex and implicit that it needs a good sense of rhythm to even figure out where the "one" is. Just like some people cannot comprehend jazz harmony - they simply cannot track the things that are happening, it's just a big incomprehensible mush.