Testing Churchill's pressure chamber
Testing Churchill's pressure chamber

This photographic gem is straight from the archives of Royal Aircraft Establishment, Farnborough. I understand it’s a pressure chamber, designed to take the strain off Winston Churchill when he was jet setting around the world. I think it dates from the mid-1940s. The aeroplane he travelled in didn’t have a pressure cabin – but lying in this chamber, Churchill could breathe a steady supply of air (and maybe smoke a cigar or two).

Hitler had something similar, apparently. Chambers like these were a must for any VIP traveller as they also offered extra security in an attack. I don’t know if there’s any evidence of Churchill using this contraption. His aircraft was once in danger but never came under serious attack.

Cold War – Hot Science

I unearthed this wonderful image when I was digging through the archives for ‘Cold War Hot Science’, an exhibition  I put together with Tim Hunkin, Robert Bud and Science Museum staff, early 2001. The exhibition marked the launch of a book by the same name. Among the many other extraordinary and alarming delights in the archive was a bomb switch for the Vulcan bomber (the aircraft designed to deliver our nuclear bombs, before we had intercontinental ballistic missiles) and some old laboratory glassware, used by Porton Down scientists to cook up Britain’s stock of the deadly Marburg Virus. Marburg is a Category 4 disease – like Ebola and Lassa Fever, it’s deadly, incurable and highly contagious.

Reactor Vessel used by Porton Down scientists to cook up Marburg virus and other Category 4 diseases
Reactor Vessel used by Porton Down scientists to cook up Marburg virus and other Category 4 diseases

Putting together the exhibition, I also remember encountering what might be the world’s most historic pieces of Sellotape. They were holding together the original ‘drop models’ (small, balsa wood aeroplanes) that were used by engineers to figure out the best design for Concorde.

Working around 1962, long before the era of Computer Aided Design (CAD), engineers dropped these models, just like paper aeroplanes, from the top of a ladder or from helicopters. They watched them gliding to the ground as they were looking for an aeroplane shape that wouldn’t roll over dangerously, as it approached the runway, despite being contoured to travel smoothly through the sound barrier. After extensive drop model tests, Farborough engineers opted to give Concorde its famous ‘ogive’ (curvy, triangular) wing shape.

When Science Museum conservators prepared these drop models for public display, they took great pains to conserve the fragile remains of Sellotape that engineers had stuck to the models, all those years ago.

We juxtaposed artefacts from the labs with press cuttings about Farnboough workers, gleaned the local papers. Somehow, these very British local newspaper cuttings made the researcher’s undercover defence work seem all the more extraordinary.

Newspaper clipping: RAE are tops in drama
Newspaper clipping: RAE are tops in drama
My favourite Farnborough clipping
My favourite Farnborough clipping



…the universe is probably full of music that we cannot perceive”Sir John Lubbock, considering the limits of the audible spectrum, 1879


An early acoustic test at NPL

Infrasonic (aka Soundless Music) was a controlled psychological experiment, in the form of two back-to-back concerts. These concerts were highly unusual because some of the music was laced with infrasound (i.e.extreme bass sound, below 20Hz in frequency).

Infrasound is of interest as it’s a sound so deep, it’s on the cusp of perception – it’s a sensation that you feel as much as you hear. It’s rbeen implicated in some eerie psychological effects, been found at sights of ostensible hauntings and it laces sacred organ music in cathedrals around the UK (more below).

This concert/experiment has attracted worldwide media interest. It’s also inspired many other artists and cognitive scientists to delve into the murky world of extreme bass sound.

Looking for more info?

10-15 June 2018 – this week I’m migrating the infrasound project notes, along with some other old pages, to this new website. Do try again later!

This experiment was put together in 2003 with a small but very welcome grant from the SciArt Consortium. Since then, I’ve been endeavouring to keep these pages live while I’ve migrated through many other websites. I conducted this collaboration as an independent scholar. I endeavour to answer as many enquiries about infrasound when I can – but please bear with me if I can’t answer extensive enquiries or respond straight away.

Our results were tentative and our statement about the project were based on an analysis of the psychological experiment designed by Prof. Richard Wiseman and analysed by Dr Ciaran O’Keeffe.

I do have many plans to take this work futher, both as an artist and as an experimenter. I’m just looking for the window of time – and the funding – to do so. In the meantime, some of my own learning from this experiment has been deployed in my music for theatre at the National Theatre, Manchester International Festival and beyond.

Original music

She Goes Back Underwater (2003). This is very early work and my style has developed considerably since 2003, but here’s the piece I created for the experiment. This version is for electronics only. There is another version for piano and electronics.

NB There is no infrasound in this recording! We had to build an infrasonic generator to generate infrasonic notes during our concert. There are some very low frequencies in this composition (which I included to mask any infrasound). But they’re not quite in the infrasonic region. Even if I had included infrasonic notes in this piece, it’s unlikely they would survive the mp3 compression process and any filtering by your computer soundcard, amps and loudspeakers (unless you have a very high-spec set-up – in which case, sorry to disappoint!).

Setting up the experiment

To delve into the curious world of infrasound, I put together a team of experimental psychologists (Wiseman et al), acoustic consultants from the National Physical Laboratory and fellow musicians, including the pianist (Genia) who would perform live on the night. Our aim was explore some tantalising claims about infrasound and put them under scientific scrutiny. Of particular interest were its reputed emotional effects. Infrasound is used in sacred music, for instance during cathedral organ recitals, and there is debate about why it’s used. Some people say it adds a sense of awe to the music – it puts a shiver down your spine. Others say that giant infrasonic organ pipes are nothing more than room dressing. Stranger still, infrasound has also been detected at some ostensibly haunted sites (see Vic Tandy, 1998) where it may also be making people feel very uneasy.

According to Tandy, even when infrasound comes from a mundane source, such as a faulty ceiling fan, it can give people such strange sensations, it might lead them to think they’ve been haunted. This was enough information to encourage us all to test the effect of infrasound in a live musical performance.

Setting up a dry-run of the experiment. This open rehearsal took place at Liverpool Metropolitan Cathedral. Photo: Dan Simmons, NPL
Setting up a dry-run of the experiment. This open rehearsal took place at Liverpool Metropolitan Cathedral. Photo: Dan Simmons, NPL


This is the Mk III robotic bell rig, designed to make it easier to take the bells to venues – earlier versions saw the bells inside a shed or scattered around a gallery, in dozens of separate boxes. Here, I’ve mounted them on an old shop fitting, salvaged by Vivien Angliss from a place in Bedfordshire that was closing down.

The Mk III bells had their first outing in the Malborough Theatre’s inaugural Steampunk night (Brighton – curated by Tarik Elmoutawakil). I’ve also taken them to the Gasworks Gallery, Vauxhall (for a Resonance FM night, curated by Ed Baxter) and to a Spacedog night at the Freebutt, Brighton. I’ve been using them quite a bit in my own compositions for bells, saw, theremin and vocals. But here’s a video of the bells playing a classic – it’s Troika, from Prokovief’s Lieutenant Kije. Over the next few weeks, I’ll endeavour to post more videos of the bells in action.

Technical notes

The bells are being percussed by servo-driven, spring-mounted beaters. These are controlled by a LynxMotion SSC-32 servo control board, which is receiving serial signals from Max/MSP.  As you can see, the springs make the beaters remarkably responsive – they can even tackle the odd semiquaver. See also the Mk I version of the bells, in Swinging London – my automaton show for the South Bank Overture Weekend.

Introduction (with videos)

Sound clips (including R4 Today Programme interview)

Baffles on the ceiling of the National Physical Laboratory reverb chamber
Baffles on the ceiling of the National Physical Laboratory reverb chamber

The line-up

Oddities of working in a reverberant space

Relaxing in the semi-anechoic chamber

Why make reverb chambers?

Be My Baby (reverb and the Wall of Sound)

The project

In December 2006, Spacedog assembled a group of musicians in the reverb chamber of the UK National Physical Laboratory. This room has one of the longest reverberation times in Europe.

These videos show you what happened – you can read more about the project on these page. NB In these videos, the people you see on camera are the only musicians playing – no sounds have been added after the event (except during the purple intro sequence). The extra sound you’re hearing is the long tail of reverb that follows each note, as sound bounces for up to 30 seconds around this highly reflective room. You hear this tail, before you hear notes, on videos that are playing backwards.

A primer on reverbation

Reverberation or ‘reverb’ is what you hear when sound bounces off the walls, floor and other surfaces of a room, creating a mush of echoes that slowly die away. Acousticians judge how long sound bounces around the room by measuring the ‘reverberation time of the space’. Technically, this is how long it takes for the sound to decay by 60dB. The easiest way to make a rough judgement of the reverb in the room is to pop a balloon in there, or clap your hands. If the sudden impulse of noise – the pop or clap – dies away almost instantly, your room has a very short reverb. If it rings for some time afterwards, you have a long reverb.

If you’re sitting in a small, carpeted room right now, it’s likely that your reverb time will only be around 0.5 secs. That’s scarcely enough for you to notice the sound that continues after you stop speaking. A hall that has been tailor-made for orchestral concerts might have a reverb time of around 2 to 3 seconds. A large, tiled bathroom might have a reverb of 5 secs or so. St Paul’s Cathedral has a reverb time of up to 13 seconds for bass notes.

The reverberation chamber of the National Physical Laboratory (NPL) outstrips all of these. Low bass notes (around 100Hz – roughly the pitch you get on the bass string of a ‘cello) reverberate for over 30 seconds. This long reverb is no surprise when you see how the room is constructed: The room is an empty chamber with concrete floors, ceiling and walls to keep the sound bouncing around. Extra plastic panels are hung from the ceiling to add more reflective surfaces. And the walls are non-parallel so echoes bounce in all directions (this prevents the build-up of standing waves).

National Physical Laboratory

On a visit to NPL in early 2006, I met acoustic scientist Dr Richard Lord who showed me the company’s new reverb chamber. He popped a balloon in there to show off its amazing reverb. As soon as I heard this, I knew I wanted to take some of musical instruments in there. I play various musical oddities, including a waterphone and musical saw, and I thought my sounds might find a home in this strange acoustic. NPL agreed I could come along, with some other musicians, on a day when the chamber was empty.

Recording a take in the reverb chamber of the National Physical Laboratory. The longest notes on Stephen's 'cello reverberate for over 30 seconds when the room is almost empty.
Recording a take in the reverb chamber of the National Physical Laboratory. The longest notes on Stephen's 'cello reverberate for over 30 seconds when the room is almost empty.


An arrangement of sounds from Croydon’s wonderful fruit and veg market. There has been a market in Surrey Street since the 13th century.

Hear the sounds

[dewplayer: http://www.sarahangliss.com/extras/sounds/ToSurreyStreetWithLove.mp3]

Surrey Street Market, Croydon
Surrey Street Market, Croydon


I first discovered Surrey Street Market when I was taken there by Mary Webb and Jenny Gunston from Croydon Clocktower Museum. We were investigating the sounds of Croydon as part of a community arts project. I was so struck by the cries of the market sellers, I decided to make a return visit and collect some sounds for my own archive. In Christmas 2006, I put these sounds together to make a short soundpiece, celebrating the sounds of that market.

I visited the market with my good friend Rachel Attmere and the stall holders were very friendly, once they realised I was holding a microphone and not a bugging device from the council! When the trader calls  ‘Two scrubbers for a pound’, he was looking at us and smiling.

We’re very fortunate in Britain to be able to find such a wealth of beautiful sounds on our doorstep – sounds that are deeply rooted in the history of this island and the various cultures who settled here over centuries.

market stall
market stall

The theremin AV controller enables me to scrub audio and video samples live, using the pitch and volume aerials of the theremin. I created this simple but highly unusual controller using Max/MSP + Jitter.

I perform with vocalist Jenny Angliss (and sometimes with guitarists Mike Blow and Ben Kypreos too), under the band name Spacedog. If you’ve been to a recent Spacedog gig, you’ve probably seen the theremin controller in action. Here’s a video of me using the device in a rehearsal. As you can see, I’m controlling the speed of audio and video clips with the pitch antenna. I can also control volume of the samples using the volume antenna.

The music in the video is Willow’s Song (Paul Giovanni), as featured in the British classic horror film The Wicker Man (1973). Here, it’s being mixed with a sample from Hammer classic The Devil Rides Out (1968), plus a 1950s parakeet training record. I’m controlling the hypnotic voice of actor Charles Gray. Jenny is on vocals and Ben on guitar. Mike, in the green teeshirt, is cueing up the various samples I’ve prepared, as the song progresses.

Apologies for the lame sound of the ‘straight’ theremin this video – you’re hearing the sound through the desk. We were monitoring live and the gallery was so reverberant, we had to ditch every hint of vibrato to avoid complete chaos.

using the theremin AV scrubber
using the theremin AV scrubber

This version of the Willow’s Song was first performed at Atters’ Other World, the Brighton Festival Fringe, June 2008, then our sell-out show at the Sanctuary. Here, you’re watching an excerpt from a live playthough of our set in the Blank Gallery, Brighton. Lighting conditions in the gallery prevented us from filming the projected video live, so keen-eyed observers might notice that we’ve added that after filming.

Named in honour of the original theremin virtuoso Clara Rockmore, Clara 2.0 is a robot doll who can play the theremin live. I call her the ‘polite robot thereminist’ as she listens to a line from another player and moves her dolly arm to bring her own theremin in perfect tune. Well, that’s the theory…
In this jamming session, Clara 2.0 is copying a line from an old Roland SH-2 synth (which I play silently), then the line from my own theremin. When the two theremins play together, things seem quite chaotic as Clara tries to follow me while I try to lock into Clara’s line.
I created Clara 2.0 as a more theatrical alternative to the loop pedal. Clara can harmonise in thirds or other intervals, as well as play in unison. She does put in the occasional appearance at live gigs although she can be temperamental, unless there’s plenty of set-up time. I’m currently experimenting with ways to make her work more reliably out-of-the-box, so I can take her on the road more often.

Duetting with robot thereminist Clara 2.0
Duetting with robot thereminist Clara 2.0

The uncanny valley

Paul Attmere and Clara 2.0
Paul Attmere and Clara 2.0

Although I haven’t offered her up for academic scrutiny, I do feel Clara 2.0 supports Mori’s ‘uncanny valley’ hypothesis (1970). I appreciate the uncanny valley is a contentious theory that needs further research. However, when I present Clara 2.0 in live performances, I find she is sufficiently human-like to unsettle the audience, in line with Mori’s theory. The exposed mechanical and electronic parts, on her convincingly baby-like frame, seem to augment viewers’ feelings of unease. People are particularly uneasy when they see Clara 2.0 in purposeful motion (as Mori’s theory predicts). Clara 2.0 has helped me to explore these issues of uncanniness and to experiment with an audience’s empathy towards inanimate objects.

No mouse – no midi

As a theremin-player, I have an affinity for fluid tuning and a natural antipathy towards midi, the musical interfacing protocol that describes pitch using discretely varying numbers. I’m also disinclined to watch live musical performances that use only a laptop, keyboard and mouse. Compared to a theremin, the keyboard and mouse create an impoverished interface, one that can’t offer the fine gestural, expressive control that is so valuable to a live performer. Clara 2.0 offers me a more theatrical, expressive alternative to the mouse – especially when I ask her to play back copies of my own theremin playing.


You’ll notice that Clara 2.0 has a whisker of metal on the end of her whisk. This tends to vibrate when she’s playing, giving her sound a pleasing Rockmoresque vibrato.


Thanks to everyone at Dorkbot London and the Hands off Festival, 2007, for their encouragement and useful tips after viewing some early outings of Clara 2.0. In particular, I’d like to thank theremin maker Jake Rothman for his extremely useful electrical advice (Clara’s insides are now lined with silver foil) and Gordon Charlton, whose virtuosic egg whisk numbers inspired Clara’s current look. Thanks also to Emmet Spier for screwing her arms on better and taking the photos on this page, Mike Blow for suggesting I try out this classic tune and Colin Uttley for playing the bass riff. With apologies to the great Roy Budd, composer of the jaw-droppingly gorgeous Get Carter theme.

Sarah Angliss plays the saw at the Tusk & Garter Club, Brighton (photo Peter Kalen)

Fancy learning the saw? Then you’ve come to the right page – just get yourself a saw, a bow and some rosin and read this short tutorial.

I have been playing the saw for thirty years – as a teenager I was taught to play by folk musician Bunny Nun in Watford, UK. I’ve since taught many others to play the saw, including the members of the mighty sawchestra in The Lost and Found Orchestra (Yes/No productions). I still occasionally feature the saw, alongside theremin, in my live act.


A track from my old band Spacedog – I’m on saw and Stephen Hiscock is on vibraphone.


Early test with Hugo the vent doll, before his head was roboticised, featuring a short saw solo.

Here’s a brief tutorial on the musical saw, a European skiffle instrument with a haunting, almost voice-like sound:

1) Any old saw?
2) How to make the saw sing
3) Developing your ear

Ethereal skiffle

The sound of the saw is so unexpectedly beautiful, some listeners find it hard to believe where it’s coming from. Played well, the saw really does sing. Its brilliant, ethereal sound is rather like the sound of a human voice. Saw players stroke the edge of the saw with a cello or bass bow (sometimes home-made) to make it vibrate. Occasionally they percuss it with a soft beater. They bend the instrument to swoop from one pitch to another, giving the instrument its characteristic portamento sound.

The musical saw is a wonderful ‘skiffle instrument’ – a cheap, everyday object that has been appropriated by musicians who have no money to buy classical instruments. I’ve encountered players of this traditional European instrument in Britain, Holland and the USA.

playing the saw
playing the saw

musical saw

Examples of saw playing

You can see some examples of my saw playing in the video on this page. An example of saw playing that’s easy to come by is in the film ‘Delicatessen’. One of the central characters plays the saw beautifully on his roof. Occasionally, I’ve heard what I think is percussive saw playing on recordings by the chanteuse Edith Piaf.

I’ve heard that saw playing is still quite common in Holland, for instance in bars in Amsterdam. My grandfather Emlyn was a saw player – sadly he died many years before I was born.

In 2015 I performed at the International Saw Festival in Brooklyn and was delighted to meet saw players from around the world.

These notes have been online since the mid-1990s and much copied and circulated – feel free to circulate them further but do please credit this source. I’ll add a tutorial video when I get a little time.

Thanks! Sarah


Welcome to the Telepath
support page.

Here, you can share your tips on performing Telepath, tell us how you’ve found the trick and let us know any features you’d like to see in future.

If you’re experiencing any problems with this new app, please email us directly at Telepath support and we’ll reply within 24 hours.

Thanks for your interest in Telepath
Sarah Angliss
Richard Wiseman

Telepath TV

Telepath TVSee Richard perform the trick
and reveal the secret of Telepath.


These videos are for Telepath magicians only – to watch them, you’ll need to enter our secret password. To find the secret password, go to the information screen in Telepath and click on Extra Stardust. The password is the third word you see on the Extra Stardust screen.

Known issue (version 1.01)

On the Learn the Trick screen, you will hear the entire soundtrack, not just a single sparkle, when you click on the sparkle sound link. A single sparkle should sound like this.

This issue will be fixed in the next release of Telepath – coming very soon. Updates will be free to anyone who has purchased this app.