Sonorities Festival of Contemporary Music 2011


Sonorities Festival of Contemporary Music 2011
Queen’s University Belfast
8-9 April 2011
http://www.sonorities.org.uk

Call for Works
The Sonorities Festival of Contemporary Music invites composers and artists working in new music to submit works to be presented during Sonorities 2011. The Festival will present four events showcasing works selected from an international call for participation. This event builds on Sonorities’ reputation for attracting high calibre composers and performers from all over the world to present exciting new music in Belfast. The concerts will be curated by composers in the School of Music and Sonic Arts and will focus on practices such as live-electronics, improvisation, multi-channel audio and audio-visual work amongst others. This year’s Festival will reflect current practices and trends with the aim of bringing to Belfast the best music for adventurous ears!

We welcome works by composers/performers, improvisers, new media and sound artists.
 
We encourage two types of submission (maximum 1 work per category):
 1. Live Performances
This includes laptop improv, VJ, audio-visual, live-electronics, sound poetry… Please submit the work in a documentary format that reflects the nature of the performance (e.g. audio recording, video, software, photographs).
 
2. Fixed Media
This includes Stereo works for diffusion, multi-channel works and works with video.

The Festival  will take place in the Sonic Arts Research Centre’s Sonic Lab performance space. This unique environment for the performance of electroacoustic music includes facilities for sound projection in a full 3D environment through loudspeakers located above and below the audience area. The experimental nature of the space makes it essential that selected composers and artists attend the Festival to perform their work.

The Festival will contribute towards the costs of participation with a sum of £350 per selected work/performance.

Submission Guidelines:
For fixed media work and audio recordings please submit through http://soundcloud.com/sonorities and include a short bio in the description field indicating full duration of the work and technical requirements. If you wish you can make your files private and only accessible by sonorities@gmail.com
Alternatively you can send a CD or DVD with materials including short bio and programme note (Word Doc or PDF) to the following address.

Sonorities Festival of Contemporary Music 2011
Sonic Arts Research Centre
Queen’s University Belfast
Belfast BT7 1NN
Northern Ireland
 
Important Dates:
Deadline for Submissions: Wednesday 26th January 2011 (postmark for postal submissions)
Decision Date: 9th February 2011
Festival Dates: 8-9 April 2011

Contacts:
Dr. Pedro Rebelo (Festival Chair)
Dr. Miguel Ortiz (Open Call Co-ordinator)
email: sonorities@gmail.com
 
 
Sonic Arts Research Centre
The Sonic Arts Research Centre (SARC) is a newly established centre of excellence, dedicated to the research of music technology. This unique interdisciplinary project has united internationally recognised experts in the areas of musical composition, signal processing, internet technology and digital hardware. The Centre was completed in October 2003 and was officially opened by Karlheinz Stockhausen in April 2004.
 
http://www.sarc.qub.ac.uk
 

Filter Calulation

필터 UGEn을 사용하다 보면 q값을 입력하거나 rq값을 입력하거나 Filter의 Bandwidth를 입력하기도 합니다.

예를들면, SC에서 일반적으로 쓰이는 BPF :BPF.ar(in, freq, rq, mul, add)입니다. rq의 입력이며

Help파일에는 the reciprocal of Q, bandwidth/cutoff Freq.라고 되어있지요.

그럼 Q는 어떻게 적용되는 값일까요?

여기에서 제대로 한번 집고 넘어가 보기로 합니다.

예를들어 -3dB가 cut-off Frequencies f1과 f2에서 적용된다고 했을때에

center frequency는 f0이고 1000이라고 봅니다, Q값은 다음과 같이 1.414(루트2) 적용되었을 때에,

Frequency bandwidth는 f0을 중심으로 f2-f1로 되구요.

그럼 아래와 같은 그림이 됩니다.

Filter resonance

공식은 아래와 같습니다.

Formula for the lower cutoff frequency:

Formula f1

Formula for the upper cutoff frequency:

Formula f2

Formula for the Q factor:

Formula f2

Formula for the bandwidth:

Formula f1

필터의 질이 좋다는것 (즉, 날카롭게 필터링을 한다)은 narrow-band filtering(notch)라고도 볼수 있는데 이는 Q값이 커야 가능합니다.

즉, 경사가 높은 필터는(또는 날카로운 필터) bandwidth가 작아야 가능 하지요.

그와 반대로 broad-band filtering은 q값이 작아야 하며, 결과로는 필터의 경사가 날카롭지 않고 더 평평한 경우입니다.

 Q값이 어느정도 적용되는지는 주로 귀로 들어 알지만 정확한 값을 알지는 못하게 되는 경우가 많지요.

다음 차트는 Q값이 얼마만큼 Frequency영역에 적용되는 지(pitch octave값으로) 보여줍니다. 

  

-reference: Tontechnik-Rechner – sengpielaudio