Supplementary Materials

Overview
Participant Mapping
Per-Participant Task Performance
Individual SUS Scores
Individual NASA-TLX Scores
Latency Measurements
Qualitative Feedback

Overview

This document provides participant-level supplementary data for the Hi-Audio user evaluation study. Participants are identified by an anonymous label (P01–P22) that corresponds to their entry in the anonymized per-participant document docs/Hi-Audio_Participant_Comments_Anonymized.md. All personally identifiable information has been replaced with JotForm Submission IDs.

Scoring procedures:

SUS: Standard formula — odd items: (score − 1), even items: (5 − score); sum × 2.5. Range: 0–100.
NASA-TLX (raw): Unweighted mean of 6 dimensions. The Own Performance dimension is inverted (100 − value) before averaging, so that all dimensions are oriented toward higher = greater workload.
SDs: SUS SD is population SD (÷ n = 22). NASA-TLX SD (summary statistic in README) is sample SD of the 6 dimension means.

Participant Mapping

Participant	Submission ID	Hi-Audio UUID	Recordings
P01	6416169389419749315	LhX24erm7R7i8rxSRWah76	link
P02	6409432612171376683	FSrnB4DPjFP5EwgHjekyMM	link
P03	6416147786326656385	eMWdcY56whcMayiF5oZJHG	link
P04	6420720104814184671	Bcg7LsTy8uDRaDTtTkJEWw	link
P05	6409505034176280614	3D76kkBoqxofHfut3dQHTj	link
P06	6408690289642566299	ZcnHQypCweDenC3XuWj5yS	link
P07	6413564565214864018	3nLNBNXbCVtEdosGYKuHeE	link
P08	6417239988428702414	eUtQHBH5jUDj3eCsvLmQkn	link
P09	6417715954425401224	7G9NTxoHauPEvkdkrjuQLv	link
P10	6412896872714817218	mqiFEK4x9WrB27Rewij6oT	link
P11	6413633065228695943	3ythJ29PSrH4PAkv7mP36E	link
P12	6421178822523703074	FMuW7UiGACpde4dqykt3tJ	link
P13	6419627128718388274	YDAp2nHnLnyLTPB49frora	link
P14	6421404144652090461	BVTm5sb6AsiaKnmwX7L5F8	link
P15	6421684511428984688	BSXwAVCNL8t5ECYbEgwdRd	link
P16	6420455651028514320	ZKskFBE7GN84uR4DvRi4C7	link
P17	6419757055218539765	PNX5yjFpNGd34BUi9Tn2qs	link
P18	6420494692118337517	L6F282RuqPipYu7AjQQR3c	link
P19	6420480828325347605	n7rpkV4acHLCMER6khzCgh	link
P20	6421275260197236995	UhkW6SWdK55esHa5UBF3A7	link
P21	6420550821525052209	nSiXgfRrWFFHW4beKWpYQ3	link
P22	6420655997663445267	CbGMhcPyQQaonPsBoRWAjx	link

Per-Participant Task Performance

Y = completed successfully, N = not completed.

Participant	T1	T2	T3	T4	T5	T6	T7	T8	T9	T10	Total
P01	N	N	N	N	Y	Y	Y	Y	Y	N	5/10
P02	N	N	N	Y	Y	Y	Y	Y	Y	Y	7/10
P03	Y	N	Y	Y	Y	Y	Y	Y	Y	N	8/10
P04	N	N	Y	Y	Y	Y	Y	Y	Y	Y	8/10
P05	Y	N	N	N	Y	N	N	N	Y	N	3/10
P06	Y	N	Y	Y	Y	Y	Y	Y	Y	N	8/10
P07	N	N	N	N	Y	Y	N	Y	Y	Y	5/10
P08	Y	Y	N	Y	Y	Y	Y	Y	Y	Y	9/10
P09	Y	N	Y	Y	Y	Y	Y	Y	Y	Y	9/10
P10	Y	N	N	Y	Y	Y	N	N	Y	N	5/10
P11	Y	Y	N	Y	Y	Y	Y	Y	Y	N	8/10
P12	Y	N	Y	Y	Y	Y	Y	N	Y	N	7/10
P13	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	10/10
P14	Y	N	Y	Y	N	Y	N	Y	Y	Y	7/10
P15	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	10/10
P16	N	N	Y	Y	Y	Y	Y	Y	Y	N	7/10
P17	N	Y	Y	N	Y	Y	Y	Y	Y	Y	8/10
P18	Y	Y	Y	Y	Y	Y	Y	Y	Y	N	9/10
P19	Y	Y	Y	N	Y	Y	N	N	Y	N	6/10
P20	Y	N	Y	Y	Y	Y	N	N	Y	N	6/10
P21	Y	N	N	Y	Y	N	Y	Y	Y	Y	7/10
P22	N	N	N	Y	Y	Y	Y	Y	Y	N	6/10

Individual SUS Scores

Raw item responses (1–5 scale) and computed SUS score (0–100). Odd-numbered items are positively worded; even-numbered items are negatively worded (reversed in scoring).

Participant	Q1	Q2	Q3	Q4	Q5	Q6	Q7	Q8	Q9	Q10	SUS Score
P01	3	3	2	3	3	3	2	3	2	3	42.5
P02	3	2	2	3	4	2	2	2	2	3	52.5
P03	1	4	1	1	3	4	1	5	1	3	25.0
P04	3	4	2	3	2	4	1	5	2	3	27.5
P05	3	2	5	3	3	3	4	1	4	1	72.5
P06	2	1	3	1	4	2	4	3	5	2	72.5
P07	2	2	4	3	3	2	4	2	3	1	65.0
P08	1	1	4	1	4	2	5	1	5	1	82.5
P09	3	4	1	2	3	5	1	5	3	2	32.5
P10	1	3	1	4	3	2	1	4	3	1	37.5
P11	3	1	5	1	5	1	5	5	4	1	82.5
P12	3	2	3	2	3	2	1	3	2	1	55.0
P13	3	3	2	1	2	4	5	3	2	1	55.0
P14	3	2	4	1	4	2	4	2	4	1	77.5
P15	2	1	4	1	2	1	4	3	3	2	67.5
P16	3	1	3	2	4	2	5	3	4	3	70.0
P17	3	4	3	2	2	2	1	2	3	4	45.0
P18	4	1	3	1	5	1	4	3	2	1	77.5
P19	1	2	3	2	4	2	1	1	4	4	55.0
P20	1	5	2	5	1	3	4	5	1	5	15.0
P21	2	2	4	4	2	2	4	2	1	4	47.5
P22	3	2	3	2	3	1	2	1	4	1	70.0

Individual NASA-TLX Scores

Raw dimension scores (0–100 scale, as answered by participants) and computed raw NASA-TLX score. Own Performance is shown here as the raw survey value (0 = low, 100 = high perceived performance). It is inverted (100 − value) before computing the Raw Score, so that higher values indicate greater workload across all dimensions.

Participant	Mental	Physical	Temporal	Own Perf.	Effort	Frustration	Raw Score
P01	52	33	30	54	28	21	35.0
P02	50	5	30	40	75	60	46.7
P03	30	12	25	79	57	87	38.7
P04	59	0	50	91	66	92	46.0
P05	19	13	43	50	64	27	36.0
P06	80	15	31	89	69	16	37.0
P07	65	21	31	41	50	71	49.5
P08	0	0	10	100	0	0	1.7
P09	72	29	27	23	10	77	48.7
P10	75	0	50	100	0	25	25.0
P11	50	53	0	82	21	0	23.7
P12	90	1	37	75	72	59	47.3
P13	65	10	20	65	70	85	47.5
P14	17	4	21	82	18	15	15.5
P15	30	20	20	80	30	30	25.0
P16	37	7	60	11	19	46	43.0
P17	77	11	25	74	29	77	40.8
P18	65	0	79	100	21	55	36.7
P19	81	38	16	16	55	45	53.2
P20	73	45	11	11	12	9	39.8
P21	83	0	28	0	75	80	61.0
P22	26	11	16	33	14	2	22.7

Latency Measurements

Self-reported round-trip latency from the platform’s built-in estimation tool (Task T5). Values include the signal-to-noise ratio (dB) where available. Notes reflect conditions observed in recordings or participant comments.

Participant	Measurement
P01	481.48 ms, ratio 22.57 dB (probably Bluetooth earphones)
P02	132.69 ms, ratio 32.80 dB
P03	166.27 ms, ratio 29.23 dB
P04	313.13 ms, ratio 26.65 dB
P05	218.65 ms, ratio 38.52 dB (tracks not well synced)
P06	186.71 ms, ratio 35.07 dB
P07	50.50 ms, ratio 31.54 dB
P08	217.92 ms
P09	ERROR (test run but failed due to wrong procedure)
P10	137.05 ms, ratio 29.48 dB
P11	47.94 ms
P12	597.75 ms, ratio 19.33 dB (no headphones used)
P13	206.92 ms, ratio 19.83 dB
P14	Not provided (no earphones used, feedback/echo in recording)
P15	176.71 ms
P16	119.82 ms, ratio 28.63 dB
P17	304.77 ms, ratio 28.94 dB (Android phone, probably Bluetooth headset)
P18	211.32 ms, ratio 23.91 dB
P19	469.33 ms, ratio 27.06 dB (Bluetooth buds)
P20	272.10 ms
P21	92.63 ms, ratio 33.20 dB
P22	144.52 ms, ratio 23.04 dB

Qualitative Feedback

Anonymized comments from the post-task survey ([Survey]) and follow-up email exchanges ([Email]). Evaluator notes (observations from recording review) are shown in italics.

P01

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please: clone

P02

[Email]

The origin of the noise is my microphone and the low volume, it does not come from the website!
When I clone the template, it created a new file in the Happy Birthday Instruments Collection, and thus I haven’t used the file in the Happy Birthday - User Evalutation collection. This part is quite complex to understand, I know I wasn’t the only one to struggle with this
And for the second song, yes I used a metronome (110 bpm in 2/4)
For the three recordings I did not understand at the time and I thought I just had to do one recording for the Happy Birthday song, maybe it was because the two recordings was under the same task in the pdf

[Survey]

The Clone button is insanely hard to find
I don’t think we can edit the privacy of a collection after creating it (but I can be wrong)

P03

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please: The first one, lacking the happy birthday sample
The user experience is very unclear and not intuitive

P04

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please: I did not have the existing composition mentioned in Task 1 so I created my own. I didn’t know which collection to choose for the second part of Task 1
The menu buttons are not very intuitive. It’s hard to navigate on the platform. The recording part is very intuitive and easy to manage.

P05

Evaluator notes:

(Tracks not well sync, latency might be wrong estimated or simply bad performed)

[Email]

I think I finished my tests, although I found it hard to understand what was expected. For the first, I recorder in a completely independent way two tracks, one on the guitar, one singing. For the second task, I dubbed Somebody that I used to know on the guitar and with my voice. I also found it hard navigating on the website and also figuring out what the purpose of the website is. I can’t make up my mind on whether it is similar to something like audacity or if it is aiming to look like ableton. If I did something wrong, don’t hesitate to let me know, I will gladly try again.
hi again, I tried doing the happy birthday with the template although i’m not sure i did it correctly. I submitted the survey.

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please: I didn’t really know in which section I was recording
I didn’t understand the idea behind the platform quite well

P06

Evaluator notes:

Conclusion: he confirms he added the email to invite “hiaudioparis@gmail.com” but eventually no collaborator is present which means the process of invitation was not clear enough and he did not confirm in the pop-up dialog,

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please: I didn’t really get the very first task. I didn’t have any “existing composition” to work with. So I created my own (and added the email like for the 2nd task)

P07

[Survey]

Having shortcuts can be very helpful for keyboard users (ex: space to pause).
Maybe having a functionality to normalize audio may be helpful for the recording. My voice was very low compared to other tracks.

P08

[Survey]

No comments

P09

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please: 1) Added metronome to multitrack recording; 2) The latency test wasn’t working, so I moved the tracks manually (I might did the manipulation wrong)
Other comments: 1) Poor UX 🚶 2) I took too long to locate the buttons for the latency test, metronome and composition info 3) Similarly, when it comes to navigating other people s music, the top buttons are once again clear 4) The fact that there are slashes between the buttons is very disorienting, it looks like a thread of Ariadne when it is not one at all

P10

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please: Yes. All in all, the website lacks clarity. There was no button to save your creations, therefore I didn’t know (although I supposed) that it was automatic. The buttons for useful features were placed in weird places : the clone button alone in the top right corner, how to add contributors, such things.

P11

[Survey]

No issues to report

P12

Evaluator notes:

(No headphones he says)

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please: First task wasn’t clear for me, since my instrument was singing, I didnt understand if I had to sing happy birthday twice (first time in the page where we pop after the first registration and the second after cloning a template). In doubt I sang it twice
It wasn’t very clear to me how the compositions were grouped in the collections.

P13

[Survey]

It really took my a while to find the “clone” button for a template in my navigator (top right corner)
I didn’t understand why not all track in the “Happy Birthday Languages” collection where clonable templates
I found the interface structure a bit hard to understand and navigate at first. I think using the ‘/’ slash symbol before the name of tabs on the top part is confusing, it could look like a navigator path when in fact the tabs are unrelated
I encountered a bug while recording, the “Record” button was frozen (gray-ish and couldn’t be clicked)

P14

Evaluator notes:

No latency value provided, from the recordings I can tell there’s delay and no earphones were used so there’s feedback (echo) in the recording

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please: It took me a long time to understand that I was supposed to record the happy birthday song twice.

P15

[Survey]

I couldnt find a way to splice or delete a certain part of the audio (tho you can select a precise part). I thus needed to record something all over again

P16

Evaluator notes:

He managed to change the title in collaboration but there’s no audio recorded, maybe the track was deleted before being sync with the server

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please: 1) The cloning of the project was difficult. 2) I wanted to cut or edit my recordings but I couldn’t.
I would have loved to be able to use space to play or other keys in the interface. It would have felt more natural

P17

Evaluator notes:

(On Android phone Pixel, probably bluetooth headset: Marshall Major IV) He did record Au clair de la Lune but he created a new collection and composition himself for it

[Survey]

Do you have any other comments, feedback or suggestion related to the Hi-Audio Online Platform?: 1) Most menus were very hard to find at first. 2) I had no problems finding how to record myself and to manipulate every “music related” things.

P18

[Survey]

No comments

P19

Evaluator notes:

He used “Bluetooth buds” He recorded Au clair de la lune outside the main collection

[Email]

I usually play the guitar in a band but it wasn’t near me at home so I had to sing.
For the second task, I sang Au clair de la lune (with the lyrics I remembered), using the metronome, and then added a “drums” line out of beatbox.

[Survey]

Do you have any other comments, feedback or suggestion related to the Hi-Audio Online Platform? Sometimes it is a bit weird, I also did it with my mom and she was very lost, I had to help her. It would be nice to have time signature somewhere to make it easier when we shift a track

P20

Evaluator notes:

She recorded Au clair de la lune outside the main collection

[Survey]

No comments

P21

Evaluator notes:

Nice estimation of the latency (metronome recorded) The person cloned both templates for Happy Birthday (language and instruments but did not record anything inside any of them)

[Survey]

Were there any task/s you didn’t know how to complete or did not finish due to lack of information or technical issues? Explain them please:

I don’t find how modifie the description. The place where are the buttons is not instinctive and natural. For exemple the clone’s button in the top right hand corner. (Then I don’t find the colour of buttons always instinctive)

P22

[Survey]

No comments