What type of computer did you get for your MT major? Why did you choose it?
At Western Michigan, we checked with the department and computer type didn’t matter. We sent d with the cheapest laptop we could find in the form factor that she preferred (15.6 inch screen) with at least 6 GB RAM and an Intel Core processor (i3 or higher). We found an HP on sale that met her specs for just under $400. She has been very pleased with her computer so far.
The probably for getting a drink spilled on it is fairly high, so I would recommend insurance for at least a year and turning on automatic backup of the My Documents folder to Microsoft OneDrive or equivalent (so that files are always available in the “Cloud” - this helps not only if the PC gets damaged or stolen but also allows file access from any computer). Insurance through Best Buy for d’s computer was around $90 for one year.
Requirements vary between schools and departments, so check with the school and department for any specific requirements that they may have.
My son has a MacBook Pro. He creates, edits and engineers music & videos with it. I’m not sure a Mac is necessary for an MT, but it was necessary for the type of work he wanted to be able to do. 
Both sons have MacBook Pros. One uses with Finale / GarageBand and midi keyboard for writing/composing music. Both use iMovie for recording/editing audition videos. (Four years ago, Pace offered basic Mac laptop to recipients of honors scholarship, and that one lasted until just recently.)
what size - 13", 15" ? Do they carry it around much and want lighter or mostly leave it in the dorm?
My D has a 13" MacBook Pro. She takes it to all “academic” classes- I don’t think it goes to studio with her.
D picked a 15.6 inch screen as a compromise between “highly portable” and “amazing screen to watch rom-coms on Netflix.” She does lug her laptop to do homework backstage during rehearsals but rarely to class.
My D took her old PC based laptop that she used throughout HS with her to college. It’s been more than adequate for her needs- she actually uses her iPad for almost everything (she’s even been known to write papers on it) and only uses her laptop when it’s impossible or impractical to use the iPad. We offered to replace it before she headed to school - but she continues to insist that she is fine.
Our D has an older Macbook that she used even in high school. It’s been fine.
My D has a pretty basic Dell that has been just fine. We did get her a laser printer for her room (they have come way down in price and we got a really good deal) that had been terrific because it is very low cost per page compared to inkjets, and faster. So the printer is definitely something else to consider. Some schools may let them print for free, but U Hart is like $0.05 per page which adds up fast, plus the convenience made it well worth it.
UArts asks students to have a MacBook Pro, but MT students can get away with an Air. (My D has an Air and is happy with it.)
My daughter (who is VP not MT) saved up during the summer during her Freshman year to buy a MacBook Pro. We paid half; she paid the rest. Within two months it was stolen from her dorm. Because we had paid half in cash, we couldn’t make a claim with our credit-card company for the loss. We bought a replacement and two months later, her flatmate spilled water over it, rendering it useless. We are now on MacBook #3. We’re also on printer #3–two color printers that mysteriously stopped working while guzzling high-cost color ink. Printer #3 is the cheapest we could find–b/w only. It is fine! I highly recommend finding a b/w printer, as the cost of those color inks is ridiculous.
Before you purchase a printer, check out the school’s IT system services. At d’s school and my son’s school, the first 300-500 pages per semester are free when printed in one of the many computer rooms around campus (well, the pages are not actually free, the cost is rolled into one of the many required fees). Neither has ever used up all their free pages.
My kids both got fancy schmancy Mac Book Pro’s for their high school graduation gifts. They both had Mac’s that they got in middle school that were workhorses and lasted A LONG time. I’m totally a Mac fan.
And I’ll cosign @EmsDad on the printer … both my kids (at different schools) use the printers that are available at the school.
Just a note on Macs, they normally have a sale for post-secondary students sometime between the end of April to mid August. Certain schools also qualify for further discounts, again you can see this via the education section on the Apple website. As well, if one is choosing the 15" over the 13" purely because of the screen size (vs needing the extra processing power / etc), purchasing an external monitor is also an option - I spent the extra money upgrading the hardware of my 13" mac and purchased a 30" external monitor that I use for bigger projects!
In terms of printers, Brother Printer’s are incredible - I’ve had a Brother HL-2140 black and white printer for almost 6 years now, and while the toner cartridges are admittedly pricey ($70), I’ve only ever had to purchase 3 cartridges in the time that I’ve had it (The High-Yield cartridges claim to last for 2,600 pages). Haven’t had to maintain it, and no issues whatsoever. (Edit: I just quickly searched up Brother Printers on the Staples website and wanted to add that I purchased the printer itself for $100)
Also adding a disclaimer that I am currently a Political Science major finishing her first degree before doing a second undergraduate in the Performing Arts, and that the use of the items listed above were not used within the context of a Performing Arts major (though I’m hoping that they will all last me through the second degree as well!).
MacAir has been great. Idk about other students or programs but my daughter records all her voice and some videos of performance work on either her iPad or iPhone. We ended up getting her a phone with 128 gb because she uses so much space recording and sometimes it’s a few days before she has time to back up and make more space.