For music, tempi, beats, at least. It is as if the very place where the music is played was, is, part of the music itself, just like one extra big instrument being part of the band.

Interestingly, there is an absolute critical size, for rooms, around  the 100 m2 range where sound start to react completely differently. This paradigm shifting dimension interact with how the music can be played and/or perceived in a said room. Smaller that that size, you are perfectly free to play at any tempo you fancy, but, you are stuck with notes or scales sounding better than others. Bigger than 100 m2 and it is exactly the opposite: you are welcome to play in any key your fancy, but the room dictates what works and what doesn’t in terms of tempo. Ask the Rolling Stones.

This is totally predictable, in small room the modes, the fundamental resonances, will reach the audible range but echo & delay will be so short that they will not be audible, let’s say below 20ms, while in big rooms the opposite happens, room resonances are so large that they disappear below the lower limit of our audible range, let’s say below 30 Hz… while suddenly echoes and delays become audible, that is the times when these extend to 30 or more milliseconds and your hear them and this influences the rhythm of your music. 100 m2 can therefore be viewed as the approximate critical distance where room modes are still very audible while echo still are not, as per the experiments of Dr Helmut Hass in 1951…

Roughly, in a 10 m3 volume, a room will generate its firsts, more importants mode resonances or cancellations at up to 70’ cycles, whereas at 20 m3 already drops at 36 Hz. So by the time your venue has reached Metallica proportions you are well out of trouble, with the highest potential annoying mode peaking at 25 cycles for a 30 meters wide cube. In rather opposite reasoning, 30 meters will give 87 milliseconds delay, while 20 meter gives 58 and 10 shows a mere 29 milliseconds. 30 ms, is the exact timing where your brain starts to be fooled by the short time difference. Where, in order to get the stuff processed alright somehow, your brain decides that these two sound arriving almost but not quite at the same moment can be considered as one single information.

This dictates what works in which sort of venue and this is why you have stadium bands and club bands and cave bands and garage bands… and this is not new news

Note: that while your brain may agree with itself to consider two identical signal arriving with a slight time difference as one single unique sound, it does not prevent that said sound to be severely degraded by interferences and cancellation due to time differences.

Chamber music was written for … a chamber and played in a tiny venue in front of a small party of individuals of noble extraction. As the court gathering got bigger, instruments, writing methods and room had to be adapted, thus orchestras grew bigger and symphonic orchestras and pianoforte appeared and music was written for these. Symphonic Orchestra played for parties of several hundred in rooms and acoustics purposely built to house the whole thing, orchestra and audience. This determined the tempi of the pieces as well as the frequency content and dynamics.

So, to me a room has a beat, a groove, as well as a sound color, and the music played in it has to be adjusted to fit. That was the composer’s job when creating a piece (in his head!) and the director’s job, when placing and directing the orchestra, adjusting the music to the feel of the room, so that, for example, the echoes from the back would come back somehow nicely in time with the music. At least from the director.

Size attenuates sound the further from the stage you are, both by air at high frequencies and by distance (inverse square law), this shows the limits of acoustical concerts to a capacity to be, say, at around 2’000 seats. Past that limit and the size needed to accommodate this many people and the music is played so far from the rear seats that it no longer make sense to listen to it at all. The 20th century’s attempts to design classical acoustical rooms dealt with that distance phenomenon by bringing the low costs seats in the back of the orchestra instead of the back of the room. Thus hoping to restore a bit of levels and high frequency contents for these, albeit my guess is that it still makes for a mediocre to average musical experience since classical instruments, and orchestras, are by design made to project sound forward. Today,  if it really needs to be played in a big room for a large audience, I would prefer a nicely and delicately amplified version of classical symphony orchestra concert, and trust me there are ways. Compared to a dull and distant and “pure” purely acoustical thing, as we see regularly happening. This to me questions the very existence of the concept of acoustical purity in classical music. Coming back full circle, people once more compare live sound to their home hifi experience and sure enough, classical live concert will sound terribly dull and distant to them, unless seated in the first vip rows. You bet it does, as at home they are “seated” right at the director’s positions, adding unnatural presence and proximity, with extra microphones steered right at every single register of the orchestra, of course all duly edited, compressed and time aligned.

On the other hand, I more that perfectly agree with purists saying the loudspeakers are indeed degrading the beauty of a classical piece. In fact, I could not agree more about degradation being inflected on the purity of the source. That said I believe mostly that the conundrum is to be found in the stereo nature of the sound on offer, as because of the drawback already stated on numerous occasions, including distortion, localisation deltas and particularly in the case of orchestra, a severe folding of the original, beautiful, wide sound image. I just believe that a carefully designed multichannel Superdiff systems, possibly completed by an enhanced room acoustics system can do wonder to convey classical music appropriately, for large rooms or open air events,  to the best standards classical artists may have or require.

As seen above. Rooms, small ones, even have a sound, a tone, . That is, up to a certain size, the low end resonances, the room “modes”, can be heard. It means certain songs, in certain keys, will fit better, will work better in some specific venues than in others. Sure enough, on some evenings in some venue, the very songs that sounded so cool last night sound plain straight awful and in every chorus, for example, that low E root note triggers the whole house to shake and rattle along with ever piece of metal in the building, dusting the ceiling from a few years of happy clubbing in the process. Congratulations, you have just hit one of the primary room modes of the place and there’s not much you can do about that, apart from “eqing” the hell out of the specific note, losing the low E in the process, or transpose a half step so as to avoid hitting that mode, or even better… play a bigger room. Yes, the larger the room the lower the room modes tend to move, to a point where room modes disappear completely from your hearing range. Cinema theatres usually are at the minimum required size or larger and this is why, along with a few neat tricks cinema industry did to make sure thing are correct sound wise, make for an enjoyable listening experience at the movie, particularly when compared to live sound, but more on that later. Or play open air event, in open air there are no room modes nor room resonances at all, in open air you are free to play in any key that you may wish at it can sound great, provided the sound system is adequate, and provided you have or need one. More on that later too, soon…

Obviously, small venues can be acoustically treated and tuned to sound good at any frequency, but this requiring rather costly, thick and large wall and ceiling treatment and since small rooms are, by nature, small, I still have to see one for real…

The Rollings Stones are the perfect example of the evolution of listening habits. They started aiming for pubs, ended up playing, inventing, stadium concerts. They have been through the whole process. Because, as much as a stadia have no room modes to deal with, they have a tempo, an audible size too. This is why you have stadium bands with their music, along with their habits, stage experience and charisma pretty much created accordingly. And I bet Coldplay or U2 would now make for a laughable experience if playing your local pub, all the while your local punk combo would rate rather poorly if playing to more than a few hundreds.

My advice, if you want to make it big as a DJ or a band, is: start to write big, think big, sound big already, and start to use long reverb and long delays and air on your mixes… Fake it till you become it…

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