Alright I analyzed my 1 hour and 5 minutes of recording the obelisk sounds at obelisk E1 in Solo Play.
The following is a compilation of all the "strings" of high-pitch encoded data in that 1 hour and 5 minutes (30 strings in total, however the last one is incomplete - the recording was stopped midway through).
WARNING: HUGE PICTURE.
Some things to note about the data:
1) Throughout the recoding, the obelisks introduces a bit of noise in the recording, I have shown it here:
2) All of the "strings" end (or start, if read from right to left!!!) in the same pattern, 100%. It is quite easy to notice if you check out the recordings. (Consists of 1 narrow long line, 4 sets of horizontal lines and a huge big block at the very right.)
3) The strings consist of 6 different constructs: Horizontal lines, narrow long vertical lines, medium long vertical lines, medium top-side vertical lines, large bottom-side vertical "lines", The Terminating Block (or the beginning block?!)
4) The horizontal lines often change pitch and for the most part there should be 10 of them (though in the terminating block there is a column of 11 horizontal lines...?). Other people working on this part of the puzzle seem to disregard the horizontal lines but I personally think that is a mistake.
My guess is that this is a numbering system of some sort, however... I was not able to decode it (I am not that smart, I guess), but perhaps someone who IS smart could take a look at the data and try?
All of the spectrograms individually can be found in this .rar:
https://www.dropbox.com/s/niamhdm6mw39nzq/alien strings.rar?dl=0