TMI about loudspeaker horns

[JohnRoberts]

https://www.facebook.com/toastyghost/videos/10156413760353142/

Here is an almost 2 hour long video of a panel discussion at a recent industry show involving loudspeaker design heavy weights.  The nominal topic is speaker horns but they veer into driver physics,  EQ, etc.

Some lame, and some good questions....  About half the panel are what I consider old school, and a couple that I consider modern cutting edge loudspeaker engineers.

Tom Danley on the far left is IMO cutting edge with his exotic horn that combines multiple drivers to work like a single point source.  David Gunness , second from the far right is a pioneer in novel signal processing applications to improve impulse  response, but they all have decades of experience in the industry.

I rarely watch internet videos but i watched this one... I am not even a speaker guy, but I understood enough of their references to appreciate their comments and even insider banter.

My favorite anecdote was when Tom mentioned some speakers that played so loud they could light a cigarette from heating the air (175 dB??).

enjoy or not...

JR

 

[pucho812]

talk about a horny subject ;D

great stuff JR, thanks.

 

[PRR]

> speakers that played so loud they could light a cigarette from heating the air (175 dB??).

1950s? Scientific American, The Amateur Scientist column, had an air-driven whistle horn-coupled to a wad of cotton. Which ignited.

 

[JohnRoberts]

> speakers that played so loud they could light a cigarette from heating the air (175 dB??).

1950s? Scientific American, The Amateur Scientist column, had an air-driven whistle horn-coupled to a wad of cotton. Which ignited.

Tom Danley did work with NASA(?) using speakers (sound) for levitation or control of physical objects without touching. I suspect this technology might be useful for multiple things.  https://asa.scitation.org/doi/10.1121/1.2024557

Above about 160dB the air becomes nonlinear from local heating effects and a sine wave turns into a sawtooth, pretty much hurting it's utility for waveform control.

He also makes big dog loudspeakers that don't suck.

JR

[edit]  back in the day the way to make loud sounds was with sirens (mechanical). IIRC (from an old 1930s acoustics text) the waveform from them was basically a saw tooth. Coincidence ? nah...  [/edit]