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A Chat with John Schaffer, a Telecom Engineer

In your opinion, what’s the biggest difference between being a Transducer Engineer and a Telecom Engineer?

– Larger Transducers are quantified using free field microphones, infinite baffles and Thiele Small Parameters.  Transducer Engineering is mostly about High Fidelity.   Telecom Engineering involves using Type 1 Artificial Ears and Head and Torso Simulators (HATS).  Telecom Engineering borrows most of the parameters from Transducer Engineering.  From there the objective in Telecom is maximizing double talk (full duplicity) and minimizing echo.  Telecom is all about voice. 

How do the projects that you work on differ?  

– Objective projects are much easier to quantify (using data), where Subjective projects involve opinions of others  (opinions are like assholes – everybody’s got one).

2.     What have you learned on the job rather than in school?  

– My education/diploma provided a foot into the door of my career and a solid foundation in math, everything else I learned on the job – there is no substitute for experience.

3.    What would you say would be your favorite project that you’ve worked on thus far?

designing compression drivers at Peavey Electronics – this was my first job out of college and still, to this date, it’s involved my favorite projects.  Peavey Electronics is Pro Audio.  Pro Audio emphasizes reliability and objective data.

4. What kind of articles do you read/ look for in your free time? Are they related to work or completely irrelevant?   

– Articles from trade magazines:

Voice Coil, Sound and Communications, Sound and Video Contractor.  I also like to follow Online Audio Message Boards.

 

 

 

We’d like to thank John for spending some time with us and wish him the best of luck!

  • Track Name

    The Quietest Room in the World

  • Artist

    Stuff to Blow Your Mind

stufftoblowyourmind:

In Minneapolis, MN there’s a room that blocks 99.99 percent of all sound. It’s a place of intense silence, intense calm and possibly intense madness. What happens when things are too quite? Robert and Julie explore in this episode of Stuff to Blow Your Mind.

this is AWESOME. 

The UK’s Five Weirdest Sounding Places

Check out this article we found from BBC News Magazine! These unusually sounding places across the UK may not be the most beautiful, but they sure do have some crazy sound effects!

Look at more interesting articles from BBC News magazine here: http://bbc.in/ZHRyIt

St Paul’s Cathedral Whispering Gallery, London

The Whispering Gallery at St Paul's

The Whispering Gallery at St Paul’s Cathedral in London is one of the few tourist sites known for its acoustics.

Thanks to a quirk in the building, designed by Sir Christopher Wren, a whisper can travel around a wall.

 St Paul's Cathedral

Stand on one side of the dome, with a friend 110ft (33m) away on the other, and whisper into the wall. The sound will skim around, hugging the wall, and be clearly heard by your friend.

Nobel-prize winning physicist CV Raman described what he called “mocking whispers” in the gallery.

"In response to ordinary conversation, strange weird sounds and mocking whispers emanate from the wall around. Loud laughter is answered by a score of friends safely ensconced behind the plaster."

The gallery in St Paul’s is particularly adept at transporting whispers.

The sound is trapped against the inside of the curved dome wall, which is why it sounds surprisingly loud at the other side and appears to emerge from the wall.

This strange feature has been attributed to the slight curve of the walls. By tilting the walls inwards at the top, less sound goes upwards and gets lost to the top of the dome.

But like most whispering galleries, this magical property is an accidental by-product of the architectural design.

Wormit water reservoir, Dundee

The old water reservoir in Wormit near Dundee lies disused and hidden from view under someone’s back garden.

It was built in 1923 in anticipation of the population of Wormit growing, but war intervened and the town never grew to be very big. Eventually, the cost of maintaining the oversized reservoir led to it being decommissioned.

It has few visual charms, it is just a vast concrete box about 200ft (60m) long, 100ft (30m) wide and 16ft (5m) high. It has a forest of concrete pillars regularly spaced about 23ft (7m) apart and holding up the concrete ceiling.

But as you talk the acoustic immediately reveals itself. A rumble builds up and hangs around like a smog. There are balloon popping sounds like a gun being fired, with a boom that reverberates around for ages.

The time it takes sound to die away is an important measure of room acoustic quality. In a classroom it is relatively short, so a teacher’s words do not overlap and make speech unintelligible. Concert halls for an orchestra are designed with a longer sound decay, because the reverberation plays an important role in enhancing the music.

The sound takes ages to die away in Wormit. In most rooms the sound dies away because every time it reflects from a wall a little bit of energy is lost. In Wormit the room is very large so the time between reflections is very long.

Also the concrete walls are almost impervious to sound and so not much energy is lost each time the sound bounces off the walls. This is why it takes some time to die away. It is like a huge cathedral, with the great advantage that you do not have to wait for an evangelical service to whoop and clap.

Greenwich foot tunnel in London

Greenwich foot tunnel

This foot tunnel under the Thames might not be much to look at, but when the sound artist Peter Cusack asked people about their favourite sounds of London it was a popular answer because of the way it distorts voices.

Sound waves bounce back and forth across the width of the 1,215ft (370m) tunnel, distorting voices using the same physics which make some people think they can sing well in a shower stall.

You can also really let rip and hear the sound go up and down the length of the tunnel.

The recording of a skateboarder passing the microphone - listen to the audio clip on the right - sounds like a freight train because of the reflections from the tunnel walls.

When the skateboard crashed to the floor there was a reverberating echo as it hit the floor. The hard tiled walls mean the crash rattles around the tunnel for ages before dying away.

With nowhere else for the sound to go, the echo is impressively loud, travelling hundreds of metres to the end wall before returning.

Bitterns at Ham Wall, near Glastonbury

Ham Wall wetland reserve near Glastonbury in south-west England is home to arguably the weirdest sounding bird in the UK.


Bittern

Bitterns are reclusive wading birds, a type of heron which makes the most extraordinary bass sounds that can carry for many kilometres over the reed beds they live in.

Their call is often likened to a distant fog horn. It’s no surprise as it is immensely powerful. At 101 decibels at 1m, it has a similar volume to a trumpet. And at about 155 hertz, a typical frequency produced by a tuba.

The booms sound like someone blowing across a large beer bottle in the pub. Exactly what the bittern is doing to make the sound is unknown, because it is a rare, secretive and well camouflaged animal.

Rare video footage has shown the bittern’s throat swelling up and the body convulsing as the air is gulped in.

As the males call before mating, it is assumed the females use the loudness of the boom to assess the fitness of the competing males.

The strange sound could also be a form of defence, with the males also booming during nesting, suggesting it is also used to guard feeding territories.

Anechoic chambers around the UK

There is an anechoic chamber at the University of Salford and it is the closest you can get to hearing absolute silence.

It is so quiet, in fact, that you can hear the sounds your body makes, like the blood circulating in your head or a high-pitched hiss, which is thought to be caused by spontaneous activity in the auditory nerve fibres within your brain.

A silent anechoic chamber
The chambers come close to absolute silence

The rooms are used for carrying out acoustic tests such as measuring the performance of ear plugs, loudspeakers and microphones.

They are made so quiet by having multiple walls to stop noise getting in from outside. Like a modern concert hall, the Salford chamber is mounted on springs to prevent vibration entering the inner sanctum.

If you talk in the room your voice sounds odd, and very muffled, like listening in an aircraft when your ears need to pop. The walls, floor and ceiling are covered in vast wedges of grey foam which absorb the sound reflections you would otherwise hear from the chamber’s surfaces.

This is a room that can be seen but not heard. Add the claustrophobic drama of being enclosed behind three heavy doors and this can get too much for some people who feel uneasy and ask to leave.

Doug Siebum began his career in Audio Post Production with a couple of College courses like a lot of aspiring Audio Engineers.  He first began at Sacramento City College in 2001 with just one Audio class.  He later would graduate with an Associate’s in Audio Production.  He went on to get his Bachelor’s in Audio Recording from Cal State Dominguez Hills.  In both programs there was an introduction to Audio Post Production.  During his time at CSUDH, and for about a year afterwards, he worked at an online radio station.  He also worked on a student short film called Oni Goroshi.  The director of that film, Brett Winterson went on to become an Associate Producer of a reality TV show. It was shortly after graduation that one of Siebum’s former teachers introduced him to film Director/Producer Charles Unger, who brought him onboard as a re-recording mixer (final post production mix) for his second feature film, Come Together.  Siebum mixed Come Together in 5.1 surround sound along with another Re-Recording mixer, James Morioka.  James Morioka became a mentor to him.  Come Together won several awards at film festivals and eventually got distribution through Indican Pictures.  It started out as just distribution in the USA, but now the film has international distribution.  Later Siebum would work as Assistant Sound editor for the feature film Rough Hustle.  This film stars some known names such as Michael Welch, Matt Bushell, Joe Estevez, and Natalia Livingston.  After being on that film for a year, he moved on to other things.  He worked as a Music Recordist for a documentary by Motown Bass Player Tony Newton.  Tony Newton played on albums for The Jackson 5, The Supremes, Stevie Wonder, Gladys Knight, and The Mamas & the Papas just to name a few. The Documentary is called Groovemonster.  Siebum was freelancing largely in live sound, stadium broadcast sound, and stagehand work while he interned at Hacienda post for 1 year.  It was here that he learned a lot about cutting sound fx.  Eric Freeman, Tony Orozco, and Daisuke Sawa were mentors to him.  He also interned at Wild Woods Post for 3 months.  Recently he was re-recording mixer for the short film The Love Remains.  Currently he is working on a 10 minute animated short for a series Directed by Charles Unger called the Punky Pets.  The name of this episode is The Blue Dress and it’s a follow up to International Icon.  Doug Siebum loves working on cartoons as that is mostly what he worked on at Hacienda post.  He is very excited to be working with Charles Unger and James Morioka again.
Zoom Info
Doug Siebum began his career in Audio Post Production with a couple of College courses like a lot of aspiring Audio Engineers.  He first began at Sacramento City College in 2001 with just one Audio class.  He later would graduate with an Associate’s in Audio Production.  He went on to get his Bachelor’s in Audio Recording from Cal State Dominguez Hills.  In both programs there was an introduction to Audio Post Production.  During his time at CSUDH, and for about a year afterwards, he worked at an online radio station.  He also worked on a student short film called Oni Goroshi.  The director of that film, Brett Winterson went on to become an Associate Producer of a reality TV show. It was shortly after graduation that one of Siebum’s former teachers introduced him to film Director/Producer Charles Unger, who brought him onboard as a re-recording mixer (final post production mix) for his second feature film, Come Together.  Siebum mixed Come Together in 5.1 surround sound along with another Re-Recording mixer, James Morioka.  James Morioka became a mentor to him.  Come Together won several awards at film festivals and eventually got distribution through Indican Pictures.  It started out as just distribution in the USA, but now the film has international distribution.  Later Siebum would work as Assistant Sound editor for the feature film Rough Hustle.  This film stars some known names such as Michael Welch, Matt Bushell, Joe Estevez, and Natalia Livingston.  After being on that film for a year, he moved on to other things.  He worked as a Music Recordist for a documentary by Motown Bass Player Tony Newton.  Tony Newton played on albums for The Jackson 5, The Supremes, Stevie Wonder, Gladys Knight, and The Mamas & the Papas just to name a few. The Documentary is called Groovemonster.  Siebum was freelancing largely in live sound, stadium broadcast sound, and stagehand work while he interned at Hacienda post for 1 year.  It was here that he learned a lot about cutting sound fx.  Eric Freeman, Tony Orozco, and Daisuke Sawa were mentors to him.  He also interned at Wild Woods Post for 3 months.  Recently he was re-recording mixer for the short film The Love Remains.  Currently he is working on a 10 minute animated short for a series Directed by Charles Unger called the Punky Pets.  The name of this episode is The Blue Dress and it’s a follow up to International Icon.  Doug Siebum loves working on cartoons as that is mostly what he worked on at Hacienda post.  He is very excited to be working with Charles Unger and James Morioka again.
Zoom Info

Doug Siebum began his career in Audio Post Production with a couple of College courses like a lot of aspiring Audio Engineers.  He first began at Sacramento City College in 2001 with just one Audio class.  He later would graduate with an Associate’s in Audio Production.  He went on to get his Bachelor’s in Audio Recording from Cal State Dominguez Hills.  In both programs there was an introduction to Audio Post Production.  During his time at CSUDH, and for about a year afterwards, he worked at an online radio station.  He also worked on a student short film called Oni Goroshi.  The director of that film, Brett Winterson went on to become an Associate Producer of a reality TV show. It was shortly after graduation that one of Siebum’s former teachers introduced him to film Director/Producer Charles Unger, who brought him onboard as a re-recording mixer (final post production mix) for his second feature film, Come Together.  Siebum mixed Come Together in 5.1 surround sound along with another Re-Recording mixer, James Morioka.  James Morioka became a mentor to him.  Come Together won several awards at film festivals and eventually got distribution through Indican Pictures.  It started out as just distribution in the USA, but now the film has international distribution.  Later Siebum would work as Assistant Sound editor for the feature film Rough Hustle.  This film stars some known names such as Michael Welch, Matt Bushell, Joe Estevez, and Natalia Livingston.  After being on that film for a year, he moved on to other things.  He worked as a Music Recordist for a documentary by Motown Bass Player Tony Newton.  Tony Newton played on albums for The Jackson 5, The Supremes, Stevie Wonder, Gladys Knight, and The Mamas & the Papas just to name a few. The Documentary is called Groovemonster.  Siebum was freelancing largely in live sound, stadium broadcast sound, and stagehand work while he interned at Hacienda post for 1 year.  It was here that he learned a lot about cutting sound fx.  Eric Freeman, Tony Orozco, and Daisuke Sawa were mentors to him.  He also interned at Wild Woods Post for 3 months.  Recently he was re-recording mixer for the short film The Love Remains.  Currently he is working on a 10 minute animated short for a series Directed by Charles Unger called the Punky Pets.  The name of this episode is The Blue Dress and it’s a follow up to International Icon.  Doug Siebum loves working on cartoons as that is mostly what he worked on at Hacienda post.  He is very excited to be working with Charles Unger and James Morioka again.

We were privileged to talk with Tom Heed, an experienced acoustic engineer, researcher, and currently a patent Attorney. His earliest experiences included being an acoustic engineer for International Jenson, who designed loudspeakers for OEM automotive and home applications. He continued his work at Oxford Speaker company and performed FEA/BEM analysis for loudspeaker motor systems and laser vibrometry scans. Although he is currently an attorney, he is still active in the acoustic engineering community.

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