Karlheinz Stockhausen 1928 – 2007

PRESS RELEASE

The composer Karlheinz Stockhausen passed away on December 5th 2007 at his home in Kuerten-Kettenberg and will be buried in the Waldfriedhof (forest cemetery) in Kuerten.

He composed 362 individually performable works. The works which were composed until 1969 are published by Universal Edition in Vienna, and all works since then are published by the Stockhausen-Verlag. Numerous texts by Stockhausen and about his works have been published by the Stockhausen Foundation for Music.

Suzanne Stephens and Kathinka Pasveer, who have performed many of his works and, together with him, have taken care of the scores, compact discs, books, films, flowers, shrubs, and trees will continue to disseminate his work throughout the world, as prescribed in the statutes of the Stockhausen Foundation for Music, of which they are executive board  members.

Stockhausen always said that GOD gave birth to him and calls him home.

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for love is stronger than death.

IN FRIENDSHIP and gratitude for everything that he has given to us personally and to humanity through his love and his music, we bid FAREWELL to Karlheinz Stockhausen, who lived to bring celestial music to humans, and human music to the celestial beings, so that Man may listen to GOD and GOD may hear His children.

On December 5th he ascended with JOY through HEAVEN’S DOOR, in order to continue to compose in PARADISE with COSMIC PULSES in eternal HARMONY, as he had always hoped to do: You, who summon me to Heaven, Eva, Mikael and Maria, let me eternally compose music for Heaven’s Father-Mother, GOD creator of Cosmic Music.

May Saint Michael, together with Heaven’s musicians in ANGEL PROCESSIONS and INVISIBLE CHOIRS welcome him with a fitting musical GREETING.

On behalf of him and following his example, we will endeavor to continue to protect the music.

Suzanne Stephens and Kathinka Pasveer
in the name of the world-wide family of musicians who love him,together with everyone who loves his music.

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On Thursday, December 13th 2007, from 10 a.m. to 1 p.m. it will be possible to personally say farewell to Karlheinz Stockhausen in the chapel of the Waldfriedhof in Kuerten (Kastanienstrasse).

A commemorative concert will take place soon at the Slztalhalle in Kuerten. Programme, time and date will be specially announced.

Sound detectives find the truth in sounds that are often hidden

<em>’The voice is the key to the contents of the heart and sometimes it’s the only way to find the truth.’
August 14, 2007</em>

<em>ound has been a treasure trove of truth for Bae Myung-jin, who runs the Sound Engineering Research Center at Soongsil University. Using spectrograms and other tools, he turns sounds into visible data that can be analyzed. Bae recently discovered that the voice of the Taliban spokesman in the hostage crisis belonged to at least two different people.</em>

Seeing is not believing for sound analyst Bae Myung-jin.
Bae, who heads the Sound Engineering Research Center at Soongsil University, finds that listening is sometimes a better way to find the truth.
His laboratory deals with criminal cases that require forensic acoustic investigation and he says the demand is high. However, kidnappings or extramarital affairs are not Bae’s only preoccupations.
He also devotes time to finding hidden truths in more exotic situations.
Last week he enjoyed extensive attention when he revealed that the voice found on recordings of purported Taliban spokesman Qari Yousuf Ahmadi belonged to at least two different people.
Bae uses a sound spectrogram for his analysis, although the device has its limits.

“If I have a clear voice recording of the Taliban spokesman from a good microphone, I can create a composite profile,” he said before admitting that his hope of performing an analysis of the veiled spokesman’s character remains only a distant possibility, given that Ahmadi’s voice recordings were taken in poor conditions with noise interference from satellite phones.
Bae came up with the finding that Ahmadi had a doppleganger after using his spectrogram to analyze nine recordings from July 21 to Aug. 2. He discovered that only six of them belonged to one person.
In the six recordings of the same voice, the spectrogram showed relatively few fluctuations and many repetitions of “uh” between words, meaning that the speaker had remained calm and thoughtful, Bae explained. Yet, the other recordings had a higher tone of voice and showed more active fluctuations, meaning that the speaker made many extra tongue movements. “The difference in resonance, frequency and spectrum proves that the speakers have different oral structures,” Bae said.

Bae’s past cases include a private investigation of the assassination of First Lady Yuk Yeong-soo, wife of former President Park Chung Hee.
Yuk was shot and killed on Aug. 15, 1974 during a ceremony to commemorate Korea’s liberation from Japanese colonial rule. It was widely believed that Yuk died after being hit by bullets fired by the assassin, Moon Se-gwang, an ethnic Korean who lived in Japan. However, Bae helped prove that it was a bullet from Yuk’s bodyguards that accidentally killed the first lady.
“After running the recording through the spectrogram, I extracted the hidden sound of a bullet being fired that matched the exact moment of Yuk’s collapse,” Bae said.
Other memorable findings include the audiotape that took the nation by storm just before the 2002 presidential election.
The tape was presented by Kim Dae-eop, a former military petty officer, who claimed it was a recording of conversations with Han In-ok, the wife of presidential candidate Lee Hoi-chang. The content of the tape suggested she was seeking ways for her two sons to dodge mandatory military service. Bae was asked to analyze the authenticity of the tape. He concluded it was a fabrication, with parts edited and altered. Kim was found guilty of falsehood and served a jail term, yet the ripples caused by the tape are remembered as a major reason Lee lost the election to Roh Moo-hyun.
Bae’s work is not limited to high-profile figures. There is also great demand for him in the field of forensic acoustics.
“From kidnapping to extramarital affairs, there are thousands of accusations each week, and I get requests for voice analysis for evidence,” Bae said.  

Commonplace products like MP3 players and cell phones usually have a voice recording function and that has led to a large increase in the amount of audio evidence that appears in criminal cases. Bae says he sometimes wants to turn his back on forensic acoustics but he cannot, because there is so much demand. His analysis has often turned out to be a key piece of evidence in court.
“Voice is the key to the human heart,” he said. “As long as human beings are born with ears and a mouth, there will be constant demand for sound analysis for truth verification.”
To increase the quality of his analysis, Bae has been collecting voice samples from a thousand people of different ages, all taken under different conditions. This will provide him with a more extensive data-base for purposes of comparison.
Bae is also interested in other aspects of sound analysis. He has come up with a machine to provide a better study environment for students.
And he recently made a “friendly index machine” based on his belief that people in love come to have similar voice identities. This experiment got him in trouble when he found his friendly index with his wife was only 81 out of 100. “That made my wife angry,” he said.
Meanwhile, Kim Ho-sik, who runs the Korea Institute of Forensic Acoustics, remains focused on the dark side of voice analysis. Mostly dealing with criminal cases, Kim said that he works closely with the police on kidnappings, murders and extramarital affairs.
One of Kim’s most important cases was the 1991 kidnapping of nine-year-old Lee Hyeong-ho, who was found murdered after 44 days. The kidnapper evaded the police dragnet and the statute of limitations expired. The case grabbed nationwide attention and was made into a hit film called “Voice of a Murderer” last year.

“When the case occurred, forensic acoustics was not very advanced in Korea,” Kim said. “It’s a different story now, and I am analyzing the voiceprints of the criminal and other related voice data to find the truth behind this child’s tragic death.”
Kim, who also teaches at the Pochon Cha University Hospital, recently worked on a violent crime that left a 20-something woman in coma. She was attacked on her way home one night as she passed a building site in Yeoju city, Gyeonggi but police could not determine what had been used as the weapon. A recording of the assault was left on a cell phone belonging to a friend of the victim. Kim broke the recording up using a spectrogram to arrive at a picture of the minutes before the woman became unconscious.
After analyzing the frequency and resonance Kim decided that the culprit had used a brick from the construction site to hit the victim in the back of the head. “It was a complex job, digging into small sounds hidden in the recordings, trying to assemble the truth,” Kim said.
Kim’s contribution was a key factor in solving the 2005 kidnapping of a 60-year-old woman in Daejeon. Using recordings of phone calls made by the kidnapper, Kim detected the sound of a golf swing, a foreigner’s voice and a woman and a child calling a dog’s name. “Based on my findings, the police detected a golf course where there were lots of foreigners and families and they eventually found the victim,” Kim recalled. “Criminals don’t pay much attention to hiding sounds, although they work hard to conceal visual evidence.”
Kim gets many requests to investigate allegations of extramarital affairs, and these days it’s mostly men doubting the fidelity of their wives. “About three or four years ago, it was the other way around,” Kim said.
He said that his job has its downside. He has been attacked after giving evidence in court and he presumes the assailants were people who were damaged by his evidence. After years of working with sound, he makes sure that his house does not have any excess noise. “I don’t even have an analogue clock with ticking hands,” he said. “My home should be a place without a sound, so that I can get proper rest.”
Kim’s biggest concern is that there will not be enough experts in his field. “Korea has about 10 experts in forensic acoustics now, although the demand is on the increase,” he said.
Another forensic acoustics expert, Jeon Ok-yeub, an official at the acoustic phonetics department of the National Institute of Scientific Investigation, agrees.
Jeon has found key evidence as well, including people who made threats to bomb major buildings in central Seoul.
She explained that everyone has a voice identity that cannot be hidden or disguised, so it is no use for suspects to try to use different accents or dialects. “Voice is a relatively honest form of data,” she said.

By Chun Su jin [sujiney@joongang.co.kr]

Warren Burt interview by Oliver Laing

<em>Published by Oliver Laing at July 29, 2007        
in Articles Issue 17.
Interview with Warren Burt
By Oliver Laing</em>

Tullamarine Airport, Melbourne, 1975: Warren Burt is asked to demonstrate the workings of his cassette recorder by a customs official. Inserting a tape of his own compositions, the airport is greeted with a ‘GGGGGRRR-a-a-a-a-NWH!’ Confirming that the cassette recorder was in perfect working order, Burt explains that this is his own music. The story may be apocryphal, but it perfectly illustrates the approach of an experimental music dynamo who has called Australia home for over thirty years.

I first stumbled across the work of Warren Burt in the hallowed music library of Sydney community radio station 2SER. I was burrowing around, trying to find some freebies to give away on my radio show. The cover looked intriguing, a photograph of some battered lumps of aluminium, which turned out to be tuning forks. The name of the album piqued my interest further, The Animation of Lists/And the Archytan Transpositions. What beguiling sounds could be contained within? Knowing that one should never judge a book, or indeed a record, by its cover, I was pleasantly surprised to find the music contained was as transcendent as its wordy title alluded.

The liner notes painted a brief biography of Warren. Here was a Yankee composer who had associated with John Cage, Pauline Oliveros, Robert Ashley and Alvin Lucier. His association with Serge Tcherepinn and Joel Chadabe had honed his formative interest in electronic music. An undoubtedly impressive lineage, but what really floored me was that the man had moved to Melbourne in 1975, and I had never heard of him! This information hit me like a tonne of bricks, and was furthered with the subsequent discovery that Warren had relocated to Wollongong in 2004 to take up a position at the university and complete a PhD. The conventional orthodoxy, at least in my mind, had avant-garde composers based in seemingly refined and distant locations such as the Darmstadt and possibly New England.

The Animation of Lists/And the Archytan Transpositions has a spacious beauty that is at once soothing, yet also engaging. Its gorgeous, sinuous tones and overtones envelop the listener in a sound world far removed from the humdrum and the mediocre. For such otherworldly music, it was, rather amusingly, recorded where the dining table usually sits, adjacent to the kitchen of Warren’s townhouse in suburban Wollongong. The recording sessions took place in the evenings between Christmas and New Year, Warren and his wife, fellow composer and artist Catherine Schieve, were involved: “There are three takes for each track. One of us would be playing the forks and the frame, which for each particular section, we would have to change over. Usually Catherine did the hand held things, hitting them and moving them back and forth in the air. In fact, she got a bit of RSI over the course of the 10 days of recording. These forks are fairly heavy; she developed these shooting pains up her arms for about three weeks after the recording session. I decided I wouldn’t make her a permanent tuning fork (player)–at least we wouldn’t go out and do that on a weekly basis”.

Between 1971 and ‘75, Warren was a postgraduate student at the University of California San Diego studying under Kenneth Gaburo. Gaburo’s interdisciplinary approach involved what he termed ‘compositional linguistics’, or music-as-language and language-as-music. One of the most striking characteristics of Warren Burt’s work is its enormous scope, or as he so humorously stated during the interview: “Interdisciplinary work R US for the past 30 years”. He draws inspiration from the worlds of experimental music, video synthesis, dance, graphic arts, intellectually rigorous writing and post-modern theory, all executed with a sense of humour and a lightness of touch that is rare to encounter within the stuffy confines of academia.

Australian composer, pianist and conductor Keith Humble was part of the faculty at San Diego, and was given the task of setting up a New Music department at Latrobe University in Melbourne. Humble recruited Warren, along with fellow composer/performers Ted Grove and Jeff Pressing, to form the nucleus of the young university’s New Music department. Warren had already formed connections with Australian musicians during his time at San Diego, including Barry Cunningham, Chris Mann and Ron Nagorcka.

Warren knew Melbourne was going to be an interesting place, but didn’t realise just how interesting; “In the second half of the ’70s, Melbourne was one of the best artistic cities on the planet, one facet of this was a vibrant and supportive New Music scene. There was just this incredible sense of inventing a new culture from various local and international historical roots. Melbourne has always had a pretty aggressive new art culture going right back to the 1880s. A lot of Melburnian artists are aware of that idea, that historic continuity. It didn’t feel like they felt that they were inventing the world from scratch. Whereas, I did get that impression when I visited Sydney, that the artists there felt like they were inventing the world from scratch, what existed before 1960 didn’t exist.”

“Melbourne had great access to culture from around the world. We had bookstores such as Collected Works and well-stocked record stores like Discurio. Their selections might have not been quite equal with what was available in New York or Paris, for example, and of course, things were way more expensive in Melbourne, but you just bit the bullet and paid the money! Money is no object when it comes to art or knowledge. As Keith Humble said, what we do in Australia is share our resources. Somebody buys a really expensive book and then they lend it to a bunch of people.”

After three years at Latrobe, Warren spent part of 1979 living and working in New York when he came to a decision; “I would really rather be working and living in Melbourne. I’d rather be within that scene and helping that particular group of people, and putting my own efforts into developing that scene.” Undoubtedly generations of Australian musicians have benefited from this decision, as Warren shares his musical knowledge and enthusiasm with a largesse that has contributed to the continued evolution of the arts in Australia. I can only reiterate Andrew McLennan’s praise contained in the liner notes of Warren’s tuning fork piece. “As a node of information, Warren is often first stop for a quick or even an epic fix”. My time with Warren conducting the interview and subsequent research opened up my mind to possibilities and tangents that were previously unknown to this writer. Indeed the challenge proved to be how to shoehorn the over-abundance of information into an article!

“Melbourne was close enough to the rest of the world, in a sense, that you could always get out and go somewhere else”. Warren proved that living geographically removed from the New Music nexus of North America and Europe was not a hindrance for the passionate and involved musician.

“In 1984 I ended up at the University of Iowa, doing an extended residency. I was in LA for most of 1986, doing an Arts/Science residency, I had a big installation at the expo in Brisbane in 1988, and in ’92 I was in Switzerland doing an installation there. In 1995 I was in Minneapolis for the American Composers Forum, 1998 I was in the San Francisco Bay Area for a good part of the year. My prodigious work output had to keep going, as I had no other form of income. Basically, for many years I faithfully read the Australia Council and state arts council booklets and kept writing away to people, and networking. I’ve found that numerically, I had to do twice as many free gigs as paid gigs, but the fact that I did those free gigs meant that people knew my work, and asked me to do the paid gigs”.

“As William Burroughs says, in one of his novels, ‘And so the years passed!’ Catherine and I have both had health problems in the past few years, which have taken a long time to come back from. With Wollongong University, various financial plans turned to vapour, so we spent some time being both poor and sick. The trip to Canada last year to play at the Sound Symposium in Newfoundland was a real re-entry into things. We’ve both done this thing in the past, performing at the highest level at national forums; it’s just when your sick, you can somehow think that your not going to be there again. This year, I’ve been invited to be the keynote speaker at the Australian Computer Music conference in June, which was a nice surprise. It’s about interdisciplinary work, so in one sense I’m a logical guy to ask. In July, I’m going down to the Liquid Architecture festival in Melbourne. In August, we’ll be up in Brisbane, working with US composer Bill Duckworth, on his interactive project I-Orpheus”.

The creative milieu of Melbourne led Warren to co-found the energetic, anarchic and influential Clifton Hill Community Music Centre (CHCMC) not long after his arrival on our shores. As Andrew McLennan states in the liner notes to The Animation of Lists, “If Warren Burt had not come to Australia in 1975, we would have had to kidnap and smuggle him in illegally”. The CHCMC was the brainchild of Warren, Ron Nagorcka and John Campbell in 1976. Located in an old organ factory, the basic concept of the CHCMC was for it to function as an ‘alternative space’ where musicians, artists and the multifarious denizens of the Melbourne scene could perform. The pragmatic constraints of fiscal prudence were not a concern, as “absolutely no money would be involved. Anyone could perform, as long as they were enthusiastic”.

Over the next seven years, Essendon Airport, Laughing Hands, Ernie Althoff, Ros Bandt and Plastic Platypus, Burt and Nagorcka’s duo, all played regularly at the CHCMC. Speaking about his duo performances with Nagorcka illustrates the anything goes nature of the CHCMC: “We would just speak into a cassette recorder, play that back while recording on a second cassette recorder, stop, rewind, play that back and record that on the first cassette recorder, just with their little internal microphone. Play that back onto the second cassette recorder, and keep swapping back and forth. Cassette recorders have plenty of distortion and noise, and it only took about five or six generations before you had shrieking noise, or the resonances of the room. Alvin Lucier’s I am sitting in a room was the first exemplar of that, done very elegantly. What we had was a cheap, bargain basement version of I am sitting in a room!”

“The end of Clifton Hill was very nice. I was overseas, Nagorcka was overseas, and Ernie Althoff, Robert Goodge and Andrew Preston were in charge. They found that a concert season came along and nobody wanted to perform. They had just gotten $1000 from Arts Victoria, the first time they had gotten any money. They said: ‘Nobody wants to perform, the place has fulfilled its purpose, we’ll shut it down and send the money back.’ In the late ’80s, the St Kilda council made the Linden Art Gallery available for Ernie, myself, Brigid Burke and Carolyn Connors to hold a monthly series of concerts. They worked really well and ran from 1986 until 1994. Once again, it was totally unfunded, but how many thousands of people saw those concerts? How many hundreds of musicians did we interact with? How many arts bureaucrats got to know our stuff? That ends up paying off in more tangible ways.”

“I made my living as a freelance composer of weirdo music from 1981 to 2001. I did all sorts of interesting and strange projects. When I left Latrobe in 1981, I got a job at the Council of Adult Education in Melbourne doing distance education, writing pamphlets about music for people out in the country. We used to say that our target audience was a 64-year-old farmer’s wife who had a BA. So think country, think needing access to cultural things, but think smart.”

This is where Warren honed his discursive and entertaining writing style: “ It had to be clear, it had to be clean and friendly, like you were talking. It couldn’t be hiding behind a wall of objectivity like academic writing. And it worked, so I decided that even when I was doing academic writing, that’s the way I would write. A number of academics have, through the years, said; ‘You’re not writing like an academic’, and I go, ‘That’s right, I am opposed to that, you have just described the enemy’.”

Five years later, synchronicity, and the untimely demise of a CSIRO computer operative led Warren to the production of the tuning forks that were used to such stunning effect on The Animation of Lists.

“The Australia Council were setting up this project called Art and New Technology. I had been doing a lot of video synthesis, and the next step was obviously computer graphics. CSIRO had a big computer graphics facility in Sydney. I went to talk about the project, the previous day the CSIRO’s computer graphics guy had died at his terminal. I thought, ‘Well, I’ll have to do another project.’ I asked if there were any CSIRO facilities in Melbourne. There was the National Metrology Lab at Monash University. Their raison d’être was to measure things, but they had metal shops, woodworking, and a chemistry lab, I decided to figure out a project and work with them. In 1970, a friend of mine had made a single tuning fork out of aluminium, just a little tiny guy, and I had used it in several pieces. So I thought, I’m going to make a bunch of these”.

“The manufacture of the tuning forks took about three and a half months. They weren’t cast; it was standard 25×40ml aluminium construction bar cut to an approximate length. The scientists thought they had a nice computer program to work out the frequencies I wanted. They were certain that they had it all nailed down, but I told them, ‘don’t you believe it, there are lots of impurities in aluminium and this is street grade aluminium!’ I wasn’t buying the really pure stuff! On a milling machine, we cut them to length, drilled out the hole in the middle and then with a bandsaw, sliced down to make the tines. After that we used the milling machine to clean them up and remove up to a ten thousandth of a millimetre at a time off the end to adjust the pitch. The forks are tuned in just intonation, which is simply a way of tuning musical intervals so that the intervals don’t beat or throb they have a purer sound. As Bill Duckworth states in his essay in The Animation of Lists, it’s as if you were listening to music and then you tune it in just intonation and it seems to come into focus. It’s just a means of getting a clearer intonation.”

Warren’s long time friendship with US composer Phil Niblock, now based in Gent, Belgium, led to the commissioning of the tuning fork pieces for Niblock’s Experimental Intermedia (XI) label. Warren was instructed to refrain from writing an electronic piece, but it certainly sounds very electronic at times; “There is a heck of a lot of beating in my tuning fork pieces. That’s because I have two different major seconds from the fundamental, which in this case was the note G on the piano. We’ve got one major second that is large, it’s slightly bigger than a major second on the piano, and the ratio is nine over eight. The other major ratio is small, that’s the ratio ten over nine. These two major seconds are about a quarter of a semitone apart, and when you play those two together you get lots of beats. My scales are actually designed so that you can get lots of beating tones and also plenty of clear tones. This is helped by the tuning forks themselves, which after the initial attack dies away, are making pretty much a pure sine wave. That is one of the reasons the piece sounds so electronic, we are not used to acoustic instruments having a very pure sustaining tone, although lots of them did. For example, glass harmonicas and various bells, although they’re outside the mainstream of what would be conventionally be regarded as an acoustic instrument, such as guitars and pianos or even violins.”

Having been so intimately involved in the Australian music scene over the past 30 years, I was curious to know Warren’s thoughts on where electronic music in Australia was heading; “I notice that everyone these days is playing turntables, turntables as instrument, as opposed to just playing records. As someone who was playing with cassette recorders for many years, that’s very nice. It’s hard to say stylistically where it is going. Everybody loves to bash the avant-garde, it’s everybody’s favourite whipping boy. So people are making predictions that we are all going to be making electronic pop music, or we are all going to be making this or that. I don’t think so, it’s just completely fragmented and there are hundreds of streams, and no one stream is more important than the other. I think the people involved in the further fringes of art music, are wrangling with conceptual challenges in a particular way that other segments of the music community are not. It’s those particular sort of intellectual challenges that I think spill over into a lot of the other fields”.

“The technology today is ubiquitous, cheap and available. We’ve never been in a situation of such abundance. For example, for a young musician starting out, what is the cheapest high quality sound producing instrument you can have? The computer, it’s cheaper than a guitar. A bad guitar is $40; a good guitar is going to cost you $1000. A good laptop that is suitable for music is going to set you back about $800-900. If you use open-source software, away you go! In terms of high quality musical instruments, the computer is the cheapest one of them all. If we believe that tools will affect the music that you make, then who knows where things are going to go? There is a symbiotic relationship between the engineer, the composer and the performer. At the same time, I look at a lot of new plug-ins, little synths and effects things, the amount of people who are coming up with really new ideas is very small. But to make a lot of those ideas available that society hasn’t even processed yet can only help”.

A person with limited musical training, who is just starting out with a computer and learning their way around the software, might be inclined to think; ‘Right, I’m going to make techno’. They find out what software the big names in techno are using and then try to emulate that sound. It takes years to become adept with the software and to find a unique voice with it, to actually start to hit your creative stride. Many musicians give up before they get to that point, maybe because they get despondent that they are not making a sound quite as chunky or polished as the people they are aping.

“Composer Elaine Barkin has a wonderful quote: ‘On the way to becoming, we each put others on for fit’ and that process can take years. It’s also learning about the software. For example, the British magazine, Computer Music continually annoys me, (I also continue to read it); because they say ‘Sound like this Pop Group!’ they actually have their market targeted to be young males who want to imitate their musical heroes. For those of us who thought that imitation was something that you left behind in high school, well, OK…”

Warren Burt certainly left school yard imitations behind quite some time ago. Having swum in the deep end of New Music for over thirty years, he has amassed a substantial back-catalogue, which is currently being archived. Stretching to 75 albums, his work spans environmental recordings, sound poetry, noise, electro-acoustic manipulations, inscrutable electronics and more. Warren Burt is a man infatuated with process, visualising the polished diamonds, where others may only see uncut stones. Or, to modify that metaphor somewhat, hearing the resonating tuning fork, where others see battered, street grade construction aluminium.