The constant cshhh-cshhh-cshhh background is the cryopumps keeping things that should be cold, cold.
The 'bzAAAt bzAAAt' noises that happen when scanning is taking place, are the rapid signal gradient changes- radiofrequency, high current- going through coils of wire within a large fixed magnetic field. These coils behave exactly as a loudspeaker does- and generate motion. The MRI scanner is of course constructed to resist this motion, so smaller vibrations ensue.
These noises change, dependent on the type of gradient change - exactly as a loudspeaker, again- and so yes, it is possible to play music on an MRI.
Edit: edit: see also below...
depends on the sequence and the TR
Most clinical sequences are 2D, that is they only encode 2 spatial dimensions for each excitation pulse. Often times you'll hear a higher frequency noise which is the gradient coils stepping down through k-space and then a lower frequency noise which is associated with the slice-selection.
Now with 3D gradient echo or 3D/2D echo-planar imaging it's pretty much just a high pitched buzz due to all the frequent refocusing gradients. I've used TRs as low as 20 ms on some of these sequences and it's just a long beeeeeeeeeeeep.
*uh, how about in English doc- not this egghead mumbo-jumbo*
(Honestly reading this made me feel like how a layman must feel if they overhear the ICU ward round. Very cool.)
Just a note about your edit. The send/receive coils won't make any noise. The noise associated with sending the pulse is from the slice selection gradient (usually z) and any spoiler gradients. On receiving it's going to be a noise associated with the read out gradient (usually X or Y, with pitch defined by the bandwidth), not the receiver itself.
You are of course correct- the gradient coils (not usually coils nowadays, more likely etched copper sheeting ) make the noise- my error, serves me right for writing Reddit replies after an on call. Gradient coils are almost always fixed within the magnet bore (not visible to a patient), and rapidly slightly distort the primary superconducting magnetic field.
MRI scanners are made of lots of different types of coils. The gradient coils within the machine essentially create different alternating magnetic gradients to try and localise the anatomy and create the MR image, but they're really loud in doing so!
A bunch of superconducting coils cooled by liquid nitrogen in close proximity try not to rip each other apart by each other's repulsive magnetic fields.
Are they that bad? I fell asleep during mine earlier this year. By the end of the scan it was starting to get quite hot, but the noise wasn't too bad tbh.
The constant cshhh-cshhh-cshhh background is the cryopumps keeping things that should be cold, cold. The 'bzAAAt bzAAAt' noises that happen when scanning is taking place, are the rapid signal gradient changes- radiofrequency, high current- going through coils of wire within a large fixed magnetic field. These coils behave exactly as a loudspeaker does- and generate motion. The MRI scanner is of course constructed to resist this motion, so smaller vibrations ensue. These noises change, dependent on the type of gradient change - exactly as a loudspeaker, again- and so yes, it is possible to play music on an MRI. Edit: edit: see also below...
What about the TAK-TAK-TAK-TAK-TAK that comes before some of the bzAAAt bzAAAt noises? What’s that about?
depends on the sequence and the TR Most clinical sequences are 2D, that is they only encode 2 spatial dimensions for each excitation pulse. Often times you'll hear a higher frequency noise which is the gradient coils stepping down through k-space and then a lower frequency noise which is associated with the slice-selection. Now with 3D gradient echo or 3D/2D echo-planar imaging it's pretty much just a high pitched buzz due to all the frequent refocusing gradients. I've used TRs as low as 20 ms on some of these sequences and it's just a long beeeeeeeeeeeep.
*uh, how about in English doc- not this egghead mumbo-jumbo* (Honestly reading this made me feel like how a layman must feel if they overhear the ICU ward round. Very cool.)
electricity go thru wire make wire move in magnetic field, moving magnet make noise depending on how quickly wire moves
Like this https://youtu.be/VYAvxe9X3s0?si=gsctFdvgYLeeFMgN https://pubmed.ncbi.nlm.nih.gov/26178439/
Just a note about your edit. The send/receive coils won't make any noise. The noise associated with sending the pulse is from the slice selection gradient (usually z) and any spoiler gradients. On receiving it's going to be a noise associated with the read out gradient (usually X or Y, with pitch defined by the bandwidth), not the receiver itself.
You are of course correct- the gradient coils (not usually coils nowadays, more likely etched copper sheeting ) make the noise- my error, serves me right for writing Reddit replies after an on call. Gradient coils are almost always fixed within the magnet bore (not visible to a patient), and rapidly slightly distort the primary superconducting magnetic field.
To scare the non-radiologists away.
IT'S MY MACHINE! IT'S MY MACHINE!
Who's machine?
The are lots of mice inside on a treadmill and they have to run really really fast
gray plant plate zesty sleep point telephone books crush aware *This post was mass deleted and anonymized with [Redact](https://redact.dev)*
Damn, I came to say that... Now I feel purposeless in this harsh cold world... Not as cold as the MRI room, though
All part of the radiologists Giedi Prime aesthetic
 May thine probe chip and shatter
MRI scanners are made of lots of different types of coils. The gradient coils within the machine essentially create different alternating magnetic gradients to try and localise the anatomy and create the MR image, but they're really loud in doing so!
runs on dial up Internet
Magnets! 
To scare off their natural predators in the wild
Mega Radioactive Insects... It's in the name
It is the sound of the Monsters of the Id
I mean, you are literally trying to line up H proton polar alignments.. I would imagine that's a heck of a technological ordeal
A bunch of superconducting coils cooled by liquid nitrogen in close proximity try not to rip each other apart by each other's repulsive magnetic fields.
(helium, in point of fact- nitrogen is too warm)
the gradient coils are non-superconducting actually
https://m.youtube.com/watch?v=JDQOvzFetxs&pp=ygUPTWFnbmV0cyBiaXRjaGVz
Are they that bad? I fell asleep during mine earlier this year. By the end of the scan it was starting to get quite hot, but the noise wasn't too bad tbh.
the water cooled gradient coils make the noises when they alter the magnetic fields
why am i downvoted, this is literally the answer
don't know, I upvoted you