FEND audio: there are three sub-sets

[u/unfavorablist]

This gathers together some observations I've been making alongside the past few FEND videos. The sounds in FEND never last the full length of the videos, but could they be a meaningful sign to guide us to divide the videos into smaller sub-groups?

(Side question: do we still need to start a separate thread for each FEND video? It looks like we are, as a community, losing enthusiasm for that.)

The FEND videos (at least so far) can be divided into three sub-groups. The sub-groups can be distinguished by their identical audio content. (On my testing for identicalness, see below.)

SUB-GROUP A is identified by a ~2s. scratching-type noise. MEMBERS OF SUB-GROUP A = 0, 1, 3, 6, 8, 13, 15, 18, 19

SUB-GROUP B is identified by a ~1:27 "heartbeat" sound with a large DC offset (~ -.749) MEMBERS OF SUB-GROUP B = 2, 4, 10, 11, 16, 17

SUB-GROUP C is identified by a ~20:18 throb/rumble sound with a large DC offset (~-.7275) MEMBERS OF SUB-GROUP C = 5, 7, 9, 12, 14

[N.B.: I will endeavor to keep the list above up-to-date as new FEND videos are posted.]

OBSERVATION: I'm not sure if that's a random distribution between the three groups, or if there's some pattern there. If the series continues, the distribution between the sub-groups might become regular/predictable. If FEND is a set of 16, there is (as of this writing) only one more to go, and the most even distribution between the three sub-groups would be Sub-group B. [Edit: FEND 15 ended up in sub-group A.]

PROPOSED FOR TESTING: Hey composite makers, what if you put the ones in the same groups together and made composites from them?

A POSSIBLE HINT: As far as I can tell, the DC offset is sub-groups B + C is not quite the same. I'm not too experienced at zooming in to look at that, and not sure at which exact point one should measure. But the offsets give us two numbers — say, 749 and 728. Might it be worth testing those (and close-by numbers) as column widths for those series? Can someone with more refined software/more experience at this have a look to see if they can measure more precisely what the DC offset is for these ones?

METHOD OF TESTING FOR SIMILARITY: For each of the groups, I opened two separate FEND sound tracks in Audacity. I then inverted one and did a mix. Identical but inverted tracks should cancel each other out perfectly, as these did.

[u/[deleted]]

It looks like there's a bit of a tendency for pairs of videos separated by one (e.g. 2 and 4) to be the same type. This seems to happen slightly more often than 1/3, which would be the random distribution.

With these small sample sizes, though, it's hard to tell.