Primitive (highly sci-fi/magical) invention?

[LilTV1155]

The first paragraph, which seems to be the "description" part already brings in working principles. In addition you briefly explain the way this sort of phonograph works, but also use terminology that someone who needed the explanation would be probably confused by.



Now we get into actual feedback:

As far as functionality is concerned, you mention both mechanical and magical means of activation without specifying how it's actually used.

That and me thinking that some things don't work the way you put them there. No cement casing able to shield harmful doses of electricity from a pen sized metal rod would be in any way practical. At small scale, lead is a lot better. The phonograph cylinder floating without any immediate benefit also seems a bit off to me.
Even if it's "counterintuitive" technology, it had to make sense to the people designing it.

Can tungsten casing work over lead shielding?

As for magic, you need a Mage or an operator with a lot of magic to put their hand on the soulprint pad on the artifact's lid. The Datacase will scan into the operators souls and intentions via the magic / mana flow. Once the magic has been accepted, then all of that mana will flow through the sci-fi circuits inside the Datacase to activate it. Magic = motor + battery source

Moonlight or black flame =something like black light to activate the memory glass marbles.

 

[LilTV1155]

This is what the Datacase will look like.

 

[Kilolo]

assuming this item works perfectly (as in it's interesting, useable, and has no deus ex machina or contradict with the world magic system)

how are you going to put this inside your novel? are you planning to wrote a whole chapter solely for explaining this one item alone?
and that's only for the technical stuff in what is it, there's things like the lore of the item, the effect cause by the item, etc.

 

[LilTV1155]

assuming this item works perfectly (as in it's interesting, useable, and has no deus ex machina or contradict with the world magic system)

It's just a data storage. The inventor (not Me, really) of this Datacase . . . . . he just wanted to create a portable bookshelf of his memories, in other words - a diary bank. Everything is pulled from his own memories.

Well the Datacase does has the ability to become a potential nuclear bomb due to its extreme radioactive potentials and needs for big mana magic.

But no, no deus ex machina or machine made god thing.

Yes, there are some powerful magic and spellcrafts stored in that device. Instead of making OP situations, it will make them weaker or kill them instead.

Ex. Someone who tried to gain power to destroy whatever?
1) Their mortal body and soul expand like balloon from energy absorbing
2) Their minds get fried or a little addled
3) Mortal body literally explode as their soul implode = Instant Death
4) Very RARE - Survived at what cost? You're either completely powerless and barely alive or so weak that a rabbit can run you over like nothing.

1. Whoever opened this Datacase can only read or understand, but not allowed to abuse it
- Catch: It come with a killing curse from the bloodlust of an ancient Ayde, a species that is more ancient and primal than a Titan
- -
2. Speaking the ancient language of Ayde ( Inventor's NonHuman race ) - Igenou is required.
- Catch: That language is encrypted in Kryptomscript dialects (Secret Code language lost during one of the earliest Aydean Wars.)
- -
3. You need the artifact's permission
- Hint: It's in the soulprint pad. There's a reason why heavy mana input is required.
Most dead Users don't really know what they are feeding anyway.

how are you going to put this inside your novel?

The data of this device is the entire story, I mean the Inventor's diary, his whole life.

are you planning to wrote a whole chapter solely for explaining this one item alone?
and that's only for the technical stuff in what is it, there's things like the lore of the item, the effect cause by the item, etc.

1 side chapter and 8-20 demonstration square drawings that can explain the Datacase's sole purpose, background, functions, and etc. It will be a short story, probably intended for dark or sadistic humor.

But that side chapter shouldn't be able to interrupt the flow of the main story anyway.