

​The Man Who Invented Stereo - DiabloD3
http://motherboard.vice.com/read/the-man-who-invented-stereo

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Stratoscope
I got to see and listen to the first stereophonic sound broadcast on the
George Gobel Show on October 21, 1958. I was six at the time.

The right channel and the picture were broadcast on the local NBC TV station,
the left channel on an NBC Radio station.

My dad got everything set up for the broadcast: The TV on one side of the
room, the radio receiver on the other. We tuned in and waited.

And then when George walked across the set, you could hear his voice move from
one side to the other. It was so cool!

~~~
grkvlt
Interesting. I remember before stereo audio was available on TV in the UK,
there would often be concerts and similar broadcast with video on BBC 1, where
you muted the audio, and listened to simultaneous stereo audio on e.g. BBC
Radio 3, which was a neat hack.

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anon4
Interesting that he called it binaural recording, which is still a term today,
but with slightly different connotations. That is, what I understand to be the
common definition of binaural today is a recording done by a pair of
microphones positioned like a person's ears with the goal of creating a fully
3D audio experience when listening through headphones. This is quite different
from stereo meant to be listened to with a pair of stereo speakers. I wonder
if what we today call binaural is really what Blumlein was envisioning.

~~~
paulsutter
Actually binaural is a special case of stereo [1]. Stereo means a recording
with two microphones spaced apart. Binaural means a recording with two
microphones spaced at the distance of a human head.

[1] [http://www.soundprofessionals.com/cgi-
bin/gold/category.cgi?...](http://www.soundprofessionals.com/cgi-
bin/gold/category.cgi?category=binauralcardioid)

~~~
jonmrodriguez
> Binaural means a recording with two microphones spaced at the distance of a
> human head.

I don't think that's enough. It's about the effect of the shape of the head
and ears on the propagation of sound waves. For example, the definition of
binaural in the page that you linked to says:

> the head and ear structure affect the way sound waves are picked up

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anigbrowl
Correct. I don't have one myself, but for high-end acoustic work people
actually use dummy heads, sometimes with ballistic gel inside, to get a very
good approximation of the sound that actually reaches the ears.

For less perfect results you could just set up measurement microphones in the
right position and then convolve the result with a Head-Related Transfer
Function.

Here's one:
[https://www.neumann.com/?lang=en&id=current_microphones&cid=...](https://www.neumann.com/?lang=en&id=current_microphones&cid=ku100_description)

They cost about $10,000 unfortunately. I'd love to have one for film use but
you don't really get the effect except when listening with headphones so it's
a pointless.

Also, for film we _totally_ fake it and pan all the dialog into the center, on
both stereo and surround mixes. Otherwise it would sound like the room was
flipping around every time the camera cut back and forth between two actors
during a dialog scene, which would get very disorienting for theatrical
viewers. So when I build the audio for a dialog scene in post-production, I
aim for an approximation of what you would hear if you were floating in the
middle of the conversation just above people's heads. What you're hearing when
you watch a movie bears little or no relation to the actual acoustics of
wherever the scene was shot unless it was very quiet indeed, but is rather a
composite of 10-20 different recordings.

~~~
amelius
> For less perfect results you could just set up measurement microphones in
> the right position and then convolve the result with a Head-Related Transfer
> Function.

This sounds interesting. Could you get to near-perfection by simply increasing
the number of microphones used? Also, could using cheap microphones be
compensated by using more of them?

~~~
TheOtherHobbes
>Could you get to near-perfection by simply increasing the number of
microphones used?

No. Ears are (kind of) point sinks. Which is why dummy head stereo works so
well on headphones - it's literally recording the sound that would usually go
into your ears, as opposed to normal stereo, which records something that's
usefully but rather distantly related to what goes into your ears.

Two microphones are enough for that.

A side point is that everyone has a slightly different HRTF, so it would be
interesting to hear what you'd get with a neutral point sink recording
convolved with _your_ HRTF.

>Also, could using cheap microphones be compensated by using more of them?

No again. Cheap microphones add non-linear distortions and have a limited and
inaccurate frequency response. If you use more cheap microphones you just get
more of the same.

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noobermin
It's interesting, perhaps stereo was meant at the time for creating a more
"3D" sound experience, stereo today remains the standard for recording music.
Even though some movies and songs attempt things like including surround sound
given that the technology now exists, stereo is much more common and full
surround soundtracks are rare.

I'm curious if any audio engineers can weigh in on why stereo is still often
all that is used today.

~~~
anigbrowl
Pro sound engineer, in both music (long ago) and film.

Two basic reasons: one is that lots of people listen to music on headphones,
and two is that most people don't set up their speakers properly. Even stereo
speakers are usually not set up properly, and even most musicians don't set
their speakers up properly. _I_ don't set my speakers up properly at home. If
you want them perfect you basically need to rearrange the entire room around
that goal and my house isn't even quiet enough to make that effort worth it.
Expecting people to set up a surround system just to listen to music? Forget
it - as the lady said, ain't nobody got time for that.

In a movie theater, everything is placed pretty precisely and calibrated for a
consistent level of loudness - although mroe and more these days, films tend
to ignore established standards. Action movies are ludicrously loud and over-
produced these days, for example, and directors like Michael Bay are notorious
for demanding that playback levels be pushed into the red, resulting in
genuine ear fatigue for many audiences.

At home, you _can_ get nice results with a good home theater but again it
depends how much time and money you want to invest in making it good. I just
watch movies via the TV speakers because I don't want 6 more boxes with wires
trailing all over the place, and between living in a somewhat noisy
neighborhood and having a bunch of pets, the distractions to a great-sounding
system would just be that much more distracting, if you see what I mean.

On the other hand, if I'm watching a movie in the theater and someone starts
whispering near me I have no problem with telling them to shut up or get the
fuck out in 99.9%* of cases. Having done it, I can tell you it takes _weeks_
of painstaking work just to get an adequate competent soundtrack into shape,
so the last thing I want to hear is some jackass 'explaining' it to his
girlfriend like they're sitting in the living room.

* A very few movies benefit from vocal audience participation, and of course comedies are there to be laughed at.

~~~
jacquesm
One common error I come across a lot in home stereo installations is that
people get the phase wrong on one of their speakers, even on very high end
systems (or maybe especially there because those usually have their wires
separated out).

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billpg
(shakes fist)

I'm deaf in one ear and stereo audio has only ever been an annoyance for me.

~~~
sanqui
I'm fully hearing, but I never use a pair of headphones or earphones because I
can't stand being unable to hear what's going on around me. So stereo is a
similar annoyance to me. Fortunately some software lets you disable it.

