JSbox ᙧ

I also gotta say I don't like the image, it's very close to being good, but it's kinda teetering into looking like a very obvious composite in some places like Ihp said as well. I'd say the necks of the guys is on of the main problems, especially the one on the left. it feels like a cutout of a different head plopped onto the body, and the skin tone on either of their hands don't match their faces.

Anyway, this is certainly a very good concept, but the clinical tone can use a bit of tweaking, stuff like:

with the exception of SCP-XXXX-C, due to damaged sustained by the receptacle's lid.

irked me, in this case it's because you're calling the anomaly which you established has an SCP designation "the receptacle", when it should probably just be something like "due to damage[this was also grammatically incorrect] to it's lid" or something like that.

The description of the actual anomaly was kinda confusing and could be clearer, I understood what you were getting at a bit just by inferring it, but I don't know if others will get it with the current phrasing. Mainly this:

The primary anomalous property of SCP-XXXX causes each instance to harmonise with the noises heard by each other instance.

sentence was the thing that confused me, maybe try: "SCP-XXXX instances will vocalize noises within earshot of other instances in perfect harmony" or something like that.

These are just two points, I would go through and comb out some odd phrasing and SPaG errors throughout.

Dialogue could be better, in fact, I don't know feel like you have to have most of the last log. You could start somewhere when -4 was put onto the stage and started singing, and just go and kinda nonchalantly hint at what is happening. The fact that we hear -4 on a stage already does a lot of this, as we can pretty much gather most of what is going on from just that.

Dialogue is one of my main weaknesses as well, so I can't necessarily help you improve the dialogue besides telling you to take out a bit of the fluff and get to the point (that being the stage performance) faster. If you're going to get more critique on this, I would recommend finding someone who is good at dialogue, and possibly good at Herman Fuller stuff.

Overall, workable concept that still needs to be worked and polished more.