You are missing the point that speaker manufacturers make speakers to give the best response in an anechoic chamber because it is impractical to design something to cover every room or situation. You're argument is trying to find way to discredit room correction by developing an idea that is non-sensical and as you have said the 'What Rubbish - Heaven forbid' only really applies to your skewed argument. You really haven't heard a well implemented room correction system have you?
One of the major buyer groups reported by the dealers for the eye wateringly expensive (for us mere mortals) Steinway Lyngdorf systems which includes RoomPerfect, are musicians because they claim it reproduces closest to their original sound - go figure.
But if you want to decorate your room with large blocks of foam or anti reflection panels in an attempt to temper the damage a room can impart then enjoy
. I know what I prefer.
You are either be deliberately missing the point or perhaps you are so convinced that DSP is the best thing since sliced bread you have ignored some basic facts of acoustic life.
You mention Steinway so let’s consider a lovely Steinway grand piano standing on a stage in Concert Hall A. It sounds wonderful to every member of the audience despite some sitting in one part of the auditorium and others in another. No need to "DSP" the piano. I’m sure you agree.
Now move the piano to Concert Hall B. Do you think the piano should now be "DSP'd" because it's in a different room with different acoustics? No, both rooms are carefully set up (and the piano carefully positioned) so we enjoy both performances despite obvious differences in the sound entering your ears.
Now put a grotty old upright in these halls. It will never sound as good however much you DSP the sound. Again I presume you agree.
So, going back to my initial posting in this thread. I suggested:
Firstly get the room sounding right by sensible furnishings, etc
Install a suitable speaker that compliments the room's features
Add a little room treatment if you have the skills and it doesn't spoil the room - remember that I've said this twice before though you seem to ignore it
Lastly, and only if you've failed in getting the sound good, resort to DSP.
I'm pleased that others here appreciate the huge importance of the earlier stages in accomplishing excellent sound.
Looking at it another way, let's say you're listening room is a concrete cylinder with no carpet or furnishing. It will sound truly dreadful even with your award-winning speakers. OK your solution is to feed your speakers via an amp with DSP. Will it suddenly sound good? No of course it won't. It'll still suffer echo / reverberation, etc that no DSP could eliminate. I’m sure you'll agree this.
Now lay a carpet and furnish the room carefully, maybe change the type of speaker to suit the room (for example planars sound rubbish in my own room, DSP or not) and add a bit of room treatment. Now you should start to get a pleasant sound. Perhaps it could be further improved with DSP - probably yes in this particularly tricky room. I hope you are starting to get the point.
OK, next - put your great speakers in an exceptionally good room - akin to a recording studio or concert hall. I'm sure you wouldn't suggest it will need DSP to improve the sound. Your exceptional speakers will astonish you and your friends at the lifelike and exciting performance - even without DSP.
Now let's say you can't afford these wonderful speakers but you still have the wonderful room. You build some DIY speakers that includes a good bass driver and a good tweeter in a home-built box and a basic crossover. The drivers between them can produce a 30 Hz frequency and also an 18K Hz frequency and everything between. You don't have the skills to tune your speakers so they sound pretty dreadful. Do you think that adding DSP will make them as good as a £20K speaker system that's been designed by a respected builder and received rave reviews? You may say that your rubbish speakers have the same Seas drivers so they should sound the same by adding DSP. You are kidding yourself!
Sorry chum, you won't get a silk purse from a sow's ear however you look at it. DSP is no substitute for careful choice of speaker and careful attention to room's furnishings. If in practice DSP make a "massive improvement" then this speaks volumes about your room and / or your choice of speaker. If DSP makes little or no difference, then you have done a much better job.
If it sounds worse, in that some of the life is sucked out of the music (more MP3 than CD), it means that your system doesn't need DSP and in fact the additional signal processing that DSP entails (and please don't think it doesn't process the signal) has caused the excitement factor to be reduced. The additional signal processing has compromised the sparkle factor in a similar way that MP3 soils things compared with CD sound. I'm pleased to say that I've found this in my own system. If I engage DSP, a little of that recorded Steinway grand piano's excitement (the goosebump / tingle factor) is lost and I don't enjoy the music as much, despite it being marginally more accurate in the bass area.
Some speakers (and Steinway Lyngdorf may well be an example) have separate amps for each driver and the bass amp can include DSP to adjust for room acoustic problems with no ill effects, but I bet you a pound to a penny that the best of this type of speaker (including my own Avantgardes) will not subject the treble to the additional processing that DSP requires.
Think carefully about the scenarios I've described and (if you still believe that DSP is the answer to all acoustic problems), please address my point with a degree of logic. The important thing in life is enjoying what we enjoy and the way we achieve enjoyment in music is irrelevant. I’ve chosen to spend a ton of cash on exceptional speakers and I’ve hugely improved the acoustics in my difficult listening room without resorting to artificial room treatment. DSP processing (including RoomPerfect in a loan Lyngdorf TDAI-3400) compromises the excitement factor.
I’m happy though I know I can improve things further. You seem to achieve total enjoyment by simply adding a DSP processor. As long as we are both happy, that’s all that really matters.