Yes, its entirely possible to get highly engaging and hugely entertaining orchestral sound in a small room. In fact a small room may be even better than a large room but there are several BUTs that are required to qualify this statement.
Firstly, the big orchestral soundstage is created in your head, not in the room, BUT your head needs a very pure, accurate signal with all the minor phase and signal amplitude differentials in tact. The more clues that are missing, the less well your brain is able to build an impression of the venue. To get a full 3 dimensional impression of listening to music in a concert hall, you need to be able to hear all the hall‘s reverberations with the right timing, the right frequency spectrum, the right phase shifts and the right relative amplitudes. When all the above are received correctly by each ear, your brain puts all the clues together and creates in your conscious mind music played in a large concert hall.
When music is played in a venue there are lots of fixed relationships that need to be almost perfect to create the desired impression of a concert hall. Firstly, the time taken for a reflection to reach a wall and bounce back to the listener is directly proportional to the size of the venue/distance travelled. A longer reflection time denotes a larger hall, a shorter time a smaller hall. As the sound is travelling, its energy is dispersing, so over a given time, the amplitude of the signal drops by an amount directly correlated to the distance. Your brain uses both time and amplitude of the reflections to assign venue characteristics. Amplitude and phase differentials between the two ears provides directional information. The frequency spectrum of the reflections is also used by the brain. Time affects amplitude and amplitude affects perceived frequency spectrum so the spectrum of the reflections also must be correct in order for the brain to construct a convincing venue. .
So what goes wrong with the above. Firstly, networks and other sources lose and mask information, so in order to get the complete picture, the network, digital sources or phono chain must be good enough to preserve as much unsullied information as possible. The more accurate, pure and complete the information, the better the impression of music played in a venue. Then there’s the listening room. Recordings are equalised with a narrow range of listening room reverberation time RT in mind ( the time it takes for frequencies to decay by a certain fixed amount). If the room rt is too short or too long, the music will not sound as intended, with certain frequencies having either too low or too high an amplitude relative to other frequencies. This will either make the music dry and brittle or murky, muddy and clouded. When the music’s spacial attributes are lost, instruments become undifferentiated and those undifferentiated parts of the signal are added to other parts of the music and heard as noise, typically digital harshness, boomy bass and so on.
Then there are specific reflections reaching your ears. In small rooms the reflections arrive at your ears very soon after the primary wave and your brain sums the two...primary wave and reflection. This can cause certain frequency anomalies depending on the polar response of your speakers. Worse is a large room, where reflections arrive later than the primary wave and are heard as a separate room reverberation. This reverberation tends to mask fine detail from the recording and causes listener confusion as you are essentially hearing the reverberations from 2 rooms...the listening room and the recording venue.
So ideally, to get close to perfect sound, a small room with well adjusted RT, ideally by diffusion, speaker placement well away from walls and speaker design that allows drivers to integrate sufficiently well in the space between driver and listener are all required. In larger rooms, the same RT adjustment is required and late reflections must be minimised. Standing waves or room nodes must also be minimised.
Ultimately, the goal is to deliver all the information on a recording as accurately as possible to your 2 ears, while minimising the sonic character of the listening room, mostly by adjusting the RT to the same value the music has been equalised for, while minimising late arriving reflections and dealing with standing waves. When you get it all right, you will hear and enjoy music in any venue in which it is recorded, from small studio to large cathedral or concert hall while electronic music, with an engineer-created soundscape should sound spectacular. Real sonic fireworks.
Lead an expert blindfold into a small listening room and if the set-up is correct they should hear no sonic clue regarding the listening room and receive only information about the recording venue...in other words they should only hear a concert hall, a cathedral, a large chamber, a studio or even open air, depending on what’s actually on the recording.