title: Cascomp BJT Amplifier vs. traditional configurations

authors: Jull, Harrisson

subjects: Cascomp

abstract: All transistor circuits introduce distortion. In Radio Frequency (RF) circuits, the third-order distortion components are the most important. The quest for more linear circuits has become more important with complex-modulation as used in modern cellular phone systems. Quinn’s Cascomp Amplifier, first reported in the 1970s, promises ideal linearity and can deliver close to that promise. We review the theory and address the question of why the Cascomp has not replaced other configurations in amplifiers where low distortion is important. Calculations are supported by measurements. A new, alternative variant of the Cascomp topology is introduced and compared with the existing configura-tion. We assert that the improved linearity comes at such a price in gain that it does not make sense to use the configuration in broadband RF circuits.

text: Cascomp BJT Amplifier vs. traditional configurations All transistor circuits introduce distortion. In Radio Frequency (RF) circuits, the third-order distortion components are the most important. The quest for more linear circuits has become more important with complex-modulation as used in modern cellular phone systems. Quinn’s Cascomp Amplifier, first reported in the 1970s, promises ideal linearity and can deliver close to that promise. We review the theory and address the question of why the Cascomp has not replaced other configurations in amplifiers where low distortion is important. Calculations are supported by measurements. A new, alternative variant of the Cascomp topology is introduced and compared with the existing configura-tion. We assert that the improved linearity comes at such a price in gain that it does not make sense to use the configuration in broadband RF circuits.

year: 2012

title: Book review: GEORGES MINOIS: The Atheist’s Bible: The Most Dangerous Book That Never Existed.

authors: Simms, Norman

abstract: This article reviews the book: “GEORGES MINOIS: The Atheist’s Bible: The Most Dangerous Book That Never Existed.”

text: Book review: GEORGES MINOIS: The Atheist’s Bible: The Most Dangerous Book That Never Existed. This article reviews the book: “GEORGES MINOIS: The Atheist’s Bible: The Most Dangerous Book That Never Existed.”

year: 2013

title: HIEMPA: Hybrid Instruments from Electroacoustic Manipulation and Models of Pütorino and Aquascape

authors: Whalley, Ian

subjects: music

abstract: The HIEMPA project combined a team of people with technical, artistic, environmental and cultural expertise towards an artistic outcome aiming to extend the New Zealand sonic art tradition. The work involved collecting audio samples from the aquascape of the Ruakuri Caves and Nature Reserve in Waitomo, South Waikato, New Zealand; and samples of a variety of pütorino – a New Zealand Mäori wind instrument. Following a machine learning analysis of this audio material and an analysis of the performance material, hybrid digital instruments were built and mapped to suitable hardware triggers. The new instruments are playable in realtime, along with the electroacoustic manipulation of pütorino performances. The project takes into account the environmental and cultural significance of the source material, with the results to be released as a set of compositions. This paper discusses the background research and process of the project.

text: HIEMPA: Hybrid Instruments from Electroacoustic Manipulation and Models of Pütorino and Aquascape The HIEMPA project combined a team of people with technical, artistic, environmental and cultural expertise towards an artistic outcome aiming to extend the New Zealand sonic art tradition. The work involved collecting audio samples from the aquascape of the Ruakuri Caves and Nature Reserve in Waitomo, South Waikato, New Zealand; and samples of a variety of pütorino – a New Zealand Mäori wind instrument. Following a machine learning analysis of this audio material and an analysis of the performance material, hybrid digital instruments were built and mapped to suitable hardware triggers. The new instruments are playable in realtime, along with the electroacoustic manipulation of pütorino performances. The project takes into account the environmental and cultural significance of the source material, with the results to be released as a set of compositions. This paper discusses the background research and process of the project.

year: 2008