literally I need help with hearing one (1) note

[Altissimo]

as an aside I think it'd be real nifty if y'all had like a basic music help topic, there's the key/time sig topic but that just covers, well, that, and sometimes ppl (like me) might have questions on arrangements without necessarily wanting to wait til the submission process to put it up there, but whatever that's my suggestion

anyhow ok so
https://www.youtube.com/watch?v=xpu6dUJbfjg, this is key of Bb, the very second note in that first measure (and by extension, like measures). is it just an F in the bass, F doubled at the octave (aka an F in the upepr voice as well as lower), or bass F with upper voice high A (Olimar said he heard this but I just do not)

https://www.dropbox.com/s/5dp6luze0uh5pck/Sunflower%20Park.mus?dl=0 here is my transcription if it helps

the reason for this is bc I've known this track for like 15 years and so my like "expected" hearing of it might be clouding my actual ability to hear that note

bonus points if you can use tech to state this conclusively like Ben does sometimes

thx

[Dudeman]

Channel isolation to the rescue!
I grabbed the original music file off of zophar.net, ran it through Audio Overload and isolated the treble and bass channels. I can say conclusively that it is just an F in the bass. I only ripped the first 30 seconds of each, but given that you're only looking for that first note (and I'm assuming all future instances sound identical), this should be enough evidence. For reference:
Treble channel: https://www.dropbox.com/s/xf3utl5x8imvoil/Sunflower%20Park%20Ch2.wav?dl=0
Bass channel: https://www.dropbox.com/s/fl1xwi3mi8fo78g/Sunflower%20Park%20Ch3.wav?dl=0
Hope this helps!

[Altissimo]

Yes, it does! I presume though that it's the same for the second beat of the last measure of the 1st ending (13 I think)?

[Dudeman]

Also yes! I think it's the type of wave being used in the bass that gives off the impression of multiple tones when there are none.

[Altissimo]

That's what I thought but figured I'd get some opinions. And I guess hard facts from tech lmao. Thanks!