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Comment by bob1029 | Hacker News Reader

> A Timpani up close you can feel in your belly as though someone punched you lightly in the gut

This is the #1 reason I bought those "ridiculous" subwoofers... A lot of the experience of the symphony lives in frequency ranges that are difficult to reproduce. Anything that does a hard cutoff at 20Hz is basically neutering the larger instruments. Feeling these transients is the entire point of having someone slam a mallet into a large object.

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Interesting - but not super relevant - data point: a Symphony Orchestra at 1 meter distance at full volume produces < 20 Watts of power!

I think your average stereo is going to have a substantial problem with any kind of orchestral music, you won't be able to hear the soft passages and the louder ones will get you 911 attention assuming you could hear the softer ones. Fortunately most audio reproduction media can't do it either. But if you have access to the original masters (or digitized copies) you can get up to 80 dB range. Putting together a non-headphones based stereo system to reproduce that in a normal living room is going to be pricey.

And this is why Watt is a poor substitute for volume, because speaker sensitivity is more important. Every energy doubling (50W => 100W) is just +3dB, and you'll loose some of that due to power compression at the upper limits. A speaker with 76dB sensitivity compared to one with 107dB is quite a different experience when fed 10W. Reproducing ~110dB of acoustic power is not particularly difficult, except for the lowest frequencies which might either require high electrical power rating or impractically large horns. Some people build horns as beds to make them fit into their apartment: http://www.hifi-forum.de/viewthread-188-2426.html

That's hilarious :) I hope that apartment is acoustically insulated from the neighbors.

> I think your average stereo is going to have a substantial problem with any kind of orchestral music.

Indeed. The impedance difference between a live instrument vs a general-purpose reproduction system is almost always going to be fantastical. Just think about how loud a person's voice can get.

20 watts of power into a live brass instrument is going to require something like 500-2000 watts worth of typical audio gear to approximate at reference volume without much distortion. There are specialty loudspeakers designed to more closely approximate certain elements - which can reduce these power requirements - but then you are forced to make all kinds of other weird tradeoffs.

How ridiculous? Rotary subwoofer ridiculous? https://www.soundandvision.com/content/eminent-technology-tr...

Unclear from the article, but what audio sources are they using? Is there a meaningful 5hz signal in my Blu-ray soundtrack?

Even C0 (for instance on a Bosendorfer Imperial) doesn't nearly go that low. You'd have to synthesize the sound, I don't think any normal arrangement would pick it up even if it was present in a performance (for instance, that organ mentioned elsewhere in the thread). 70 mm Dolby Stereo tracks from motion picture reels will go as low as 3Hz. I'm not sure if that makes it to Blue-ray though, would be nice to try for a lark but not enough of a win to shell out money for.

Low frequencies can occur in nature, waterfalls, earthquakes and the like. Here is a writeup, with photos, of a multiple rotary subwoofer installation for the Niagra Falls Fury show about the creation of Niagara falls.

http://www.rotarywoofer.com/niagara%20fury%20index.html

I just had one of those 'why didn't I think of that' moments. That's really neat, thank you very much for posting it.

https://youtu.be/12X-i9YHzmE

Something like the Octobasse is amazing in person, and would be completely missing on a regular home speaker setup.

Wow. I thought that was a video overlay... but it's the real thing. Incredible.

20Hz is already pretty deep, and usually only found in home cinema subs! The deepest organ note goes down to 16Hz I think? PA subwoofers are usually tuned to 40Hz, because there is typically no energy in regular music below that cutoff. The stuff that "punches you in the chest" is actually not deep bass, but kick bass, which is above 60Hz.

No, they go down all the way to 8, that's a 64' pipe. There are only very few organs in the world that can do this and I'm not even sure if those stops are functional.

I have a 'virtual' version of that here and you simply can't hear it (you can feel it though).

See:

https://www.mixtuur.com/en/whats-the-longest-organ-pipe-in-t...

I heard they have pipes that big at the Liverpool cathedral, but they only use them when the Queen was there, as they are literally wrecking the cathedral.

Indeed it does:

https://www.liverpoolcathedral.org.uk/media/qyyd3x40/liverpo...

I totally get why they would want to limit the use of that particular register. At that frequency you're putting standing waves in the structure of the cathedral that are long enough to put significant stresses on the masonry. I've played around a bit with a 32' stop in a church and that already had me worried about the stained glass and the more delicate bits of stone work. Half that at volume must be very impressive.

I don't think it is written into a piece (at least not one that I know of) but if you play the 32' pedal C and C# together you get a ~2 Hz beat frequency that is amazing to hear but probably didn't help the church building that I worked at. :)

Hehe, that's nasty :) Yes, of course, you can get all the sums and differences by going up and down that stop and keeping the lowest note pressed all the time. You probably end up giving the wind machine a nice work out too.

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