Don’t take that as being definitive, though. There’s a number of videos I’ve seen that try to break it down, and I’m fairly certain that it has been ascertained by either the musicians or engineers involved during the recording session that a piano was used for the opening chord.
Interesting. But if these guys heard the original master tapes at Abbey Road, I think they would’ve mentioned a piano. Besides, what they played sounded exactly like the original chord. But who knows?
And another analysis.
It’s also not very obviously a piano. Here’s another breakdown with audio examples.
“Pinball Wizard” by The Who (at 24, 28, and 31 seconds)
Um, that’s not a chord. Might be an octave (which isn’t a chord), hard to tell, but might be a single note as well. And it’s a slide/glissando/hammer-on/ whatever, which also isn’t a chord.
The chord that David played that the Lord found so pleasing. I can’t provide a link because it’s a secret chord.
This is very interesting. I never knew nobody knew exactly how the chord was made.
The article below says - …when A Hard Day’s Night was recorded, the drums, bass and two guitars were all recorded onto the same track. The process of separating the instruments was done through software…
Long article but the gist is, there was a piano.
But it goes like this: the fourth, the fifth, the minor fall, and the major lift.
[SPOILER]So probably just a dominant seventh chord (which has a minor third falling down from the fourth, and a major third going up for the fifth. So, in C, it would be FGDB.)
Or just describing the chord progression of the song, which also works.[/SPOILER]
The opening chord of “Fly on a Windshield” by Genesis.
Icehouse, Great Southern Land.
The opening single synthesiser note is held for 12 seconds. When first composed Iva Davies wanted it to be nearer to 30 seconds.
The opening chord to, “Her Majesty,” on Abbey Road. which is nothing like the rest of the song (because it’s actually the last chord of, “Mean Mr. Mustard,” from earlier in the album–splicing trick.).
How about the opening to Here Comes Your Man? It sounds like a grungier version of the chord from A Hard Day’s Night.
Post #11 agrees with you. 
The classic “Pink Floyd” chord – the one that “Dogs” from Animals ends on. ("…dragged down by a stone… –> )
Don’t know the guitar-nomenclature name for it, but play an octave on the root (let’s say we’re in E minor for the heck of it, so make them octave E’s) then superimpose a Bm triad (b, d, and f#) with a g added to it in the treble.
That would spell an Em9, if you’re interested.
The opening power chord of Won’t Get Fooled Again should be on this list.
Andy Partridge of XTC is known for using certain pet chords, and one I think of in particular is the “XTC E.” Rather than a typical open E (E B E G# B E), he plays Ab B E B (top two strings not played). You can hear this all over his stuff, particularly in “I’d Like That.”
Transposed down a full step in this instance.
Is there a reason you spelled it as “Ab”? In an E chord, that’d be called a G#.
thanks! useful to know!