I have a question more or less related to the topic (and challenging the "professional" or "amateur" qualification of these two type of speaker) :
Why so many mastering studio use high-end hifi speakers as their monitors ? In particular the most regarded/wealthy/award winning ones.
To take just one example, just have a look at Galaxy studio. Mixing rooms are stuffed with big Genelec but the mastering suite have Eggleston Works speakers.
Does the professional members of the forum have some ideas on that ?
There are a few factors:-
Mixing and Mastering are quite different tasks. Firstly, mixing studios have traditionally been based on a mixing room that is visually connected to a performance room with a window. The mixing room has a huge mix console. This has meant that monitoring in mix rooms has often been a pair of nearfields placed on the meter bridge and a big pair of soffit mounted mains on each side of the window to the performance room. In this arrangement, the space for a decent pair of mid-far field monitors often does not exist.
Mastering has most often been done in rooms that dont require a huge mixing console as most of the time its only a small number of tracks being required. Many mastering rooms try to keep interference from the console and studio furniture to a minimum by removing those elements. The rooms arent connected to a performance room, so there is no restriction on how the monitors are to be placed. That opens up the possibility of mid-far field monitors.
For example B&W 802's or big Duntechs have been very popular in Mastering studios. Theres really no way those types of speakers could fit in a mixing studio.
Generally speaking, mixing rooms have also double as tracking rooms, where recording the band and mixing their songs has happened together. That's kind of the creative process and it's often got several people in the studio, including the band members...who want to hear what it sounds like LOUD, hence the soffit mounted mains.
Mastering tends not to have the whole band present. Possibly just the mastering engineer and maybe the producer. So a big expensive pair of soffit mounted mains isnt required [which are usually more expensive than even quite high end hifi speakers]. Also, Mastering engineers value their hearing more than drummers and guitar players, so they don't monitor as loud. Most nearfields don't have fully extended bass, so being able to master tracks with a good understanding of the 20-40 Hz range isn't necessarily best done on a pair of nearfields with 5" mid woofers.
So mid to far field speakers come in to play because the mastering room usually isn't full of consoles and band members. The volume of soffit mounted mains isn't required, but a full range playback system, beyond the capability of a pair of nearfields, is required. And because there are way fewer mastering studios than mixing studios, the studio monitor manufacturers have not focussed their attention on that segment.
Then there's the case that mastering engineers are 'really' into listening to the details...because that's their job. So it's not surprising that many are really into hifi as well. Or at least really into the pursuit of sound quality.