The question needs to be answered at so many different levels that it is very hard to do a good job of it due to the technical jargon that needs to be introduced. Terms like "accuracy" means so many things to so many people as I have said in my previous posts in this thread. Hence I will try to give a relatively short answer while also trying to convey the different aspects involved to the extent of my knowledge. Also, I am not a fan of home theatres and enjoying movies in it so I have never bothered to go into more details about it. So my answer is more applicable to stereo music reproduction than home theatres. To some extent it also applies to home theatre systems but there we have much more capability to reproduce the sound field better due to the more number of spatially separated sound sources (speakers
) which can potentially bring in more smoothness in the frequency response (tonal balance).
The simplest explanation regarding us not being able to hear what the recording engineer intended is because our ear-brain system makes a monkey out of us most of the time irrespective of how good the speaker is.
This is because more than the how good speaker is able to radiate sound, the engagement of our ear-eye-brain system to the sound field it is exposed to determines what we eventually hear. Based on age, demographics, and other factors including emotional engagement the hearing capabilities of people differ (the frequencies we are able to hear). Then based on similar factors there are equal-loudness contours which tell us, on an average, what is our sensitivity to different frequencies (how much we are able to hear "loud" and "soft" sounds of each frequencies). In short hearing varies from person to person. We don't have the recording engineer's brain or ears. Hence we don't hear things in the exact same way as that person.
Then there are phenomena like auditory masking which influences what we hear in the environment we are sitting in while listening to music. The things that we hear in a silent studio may not be typically what we hear in our typical rooms. Then there are differences in what we hear based on the acoustics of sound reproduction in rooms (speaker radiation characteristics/room dimensions, room treatment). Then differences will come in what we hear depending upon where we are in the reproduced sound field (a binary classification of it is as follows: free field/near field-where the direct sound from the speaker "dominates" and far field/reverberant field where the reflections from surfaces around the speaker dominate. There are more elaborate classifications too). If we are more in the nearfield and on the same intended listening axis as the design axis, the on-axis response of the speaker dominates what we hear. If we are in the reverberant field, the power response and directivity of the speaker and how the room interacts with it (I would highly recommend you see this thread
https://www.hifivision.com/threads/...-set-of-short-videos-on-room-acoustics.86875/ and go through the resources mentioned there for learning more about how different rooms sound) controls what we hear. Why? Because even a single dominant reflection that interferes with the direct sound alters its tonal balance due to the comb-filtering it causes. Therefore unless we have the same listening space (in all aspects: speakers, room, treatment) as the recording engineer, we don't even have any hope of reproducing the acoustics that the recording engineer had while he "made the music".
At least the acoustics part we can "alter" to some extent by room selection, treatment, and DSP/EQing capability. I recommend reading this post and the graphs there (my personal speaker building thread on diyaudio) to get an idea about some aspects of how room affects response:
https://www.diyaudio.com/community/threads/a-3-way-design-study.376620/post-6847339. I also recommend seeing the set up and graphs in this post to get an idea of the tonal balance change in another system placement scenario (one of my personal setups):
https://www.diyaudio.com/community/threads/a-3-way-design-study.376620/post-6847377.
I would also suggest you to read this page:
http://www.5een.co.uk/FSTNT1.htm, where there is a particular DIY speaker build. This is not to learn how to make that speaker. I am suggesting it because there are some valuable insights about interaction between speakers with rooms.
You can also refer to Kimmosto's posts that I have been repeatedly referring to in the previous posts to get an idea about the intricacies involved in speaker design/construction and why the current state of research is not enough for us to characterize everything "objectively". I keep referring to him because he is someone I personally respect for his smartness and experience (and because he is the guy to whom companies like Genelec consult when they want to design their controlled directivity speakers..
)
Also to identify the set of caveats that come with the spinorama measurements, just take a look at Erin's site here:
https://www.erinsaudiocorner.com/loudspeakers/kef_wireless_ii/ Just before every measurement and its explanation, there are explanations (a clickable arrow) of what is the premise under which that measurement is made and what it is intended to convey. This will show some of the limitations and why it should be taken with a slight 'pinch of salt'. As someone had remarked before in this thread, most of the people don't just gloss over the frequency response measurement of a speaker and call it a day. There are many who go past and read every single measurement in detail, understand it, and make their own judgements based on it.
I hope I have been able to give at least a vague idea regarding how aiming for hearing what the recording engineer heard is a fallacy and saying that everything about sound can be understood by looking at a few graphs is more like trying to 'revel in our own ignorance and ego'. Better aim would be to try for a more 'pleasurable' listening experience to 'you'. For me personally, it only comes through a combination of objective and subjective parameters. For others it could be just subjective parameters. That is their preference. My current taste in speakers is 'controlled/constant directivity speakers' (with controlled directivity waveguides/horns for upper end of the spectrum, super-cardioid, hyper-cardioid midrange and bass modules). To many others it could be some among 'direct radiator' designs (our typical 2 way, 3 way speakers, other acoustic concepts and constructs with different radiation patterns like open baffles and others), not because neither is technically superior but because it is what appeals to their senses.
I can go on for pages trying to explain the intricacies about measurements in more detail. But it is pointless (and I have other things to do
) so I wont attempt anything more in this thread.
