Michael Oehler

The octave illusion and handedness: A replication of Deutsch’s 1974 study

The octave illusion was first described by Diana Deutsch in 1974; in this phenomenon, a dichotic sequence of oscillating 400 and 800 Hz sinusoidal tones evokes different illusory percepts. At the same time, the obtained percepts were found to be dependent on the subjects’ handedness. This study investigates the influence of the handedness classification method on the correlation between reported percept and handedness in the octave illusion. After presenting the stimulus, we asked a total of 174 subjects to report their percepts and complete a handedness inventory as well as a speed tapping task. According to the right shift theory of Annett (1972, 2002) and a related study by Kopiez, Galley, and Lehmann (2010), we hypothesized that the use of performance measurement to classify handedness may clarify ambiguous correlations of subjects’ handedness with some obtained illusionary percepts. The results support the general findings of Deutsch but show that stronger effects can be found if hand performance differences are used for handedness classification. A better separation between the handedness groups could be observed, especially for the complex perception patterns.

Virtual wind instruments based on pulse forming synthesis

A new synthesis method for wind instruments is presented, the digital pulse forming. The core of that principle is that every wind instrument sound can basically be put down to its excitation impulses, which independently of the fundamental always behave according to the same principles. By controlling the pulse width and shape it is possible to generate all sound nuances that can be produced on a real wind instrument. Based on the 1975 found principles of generating wind‐instrument‐like spectra with typical stable formant areas and spectral gaps evoked by the excitation pulses of double‐reeds or lips [J. P. Fricke, Fortsch. Akust. 4(DAGA75), 407–411 (1975)], a virtual wind instrument, the Digital Variophon, is developed. The resulting software‐based version of the original Variophon, the first analog wind synthesizer using the pulse forming principles, is a further step towards the intended scientific experiment system for analyzing and synthesizing (wind) instrument sounds. Trumpet, bassoon, and oboe mo...

Audio quality in everyday listening situations

The quality of digital audio which uses a form of lossy data compression is in the focus of several studies. The experimental focus of these studies includes the fundamental difference between objective and subjective measurement methods (Pocta & Beerends, 2015), test standards (Breebaart, 2015), or signal processing (Khaldi et al., 2013; Jung et al., 2016). But there are only few studies concerning the impact of perceived quality differences in everyday listening situations (ELS). Short excerpts of recent popular music recordings were encoded with different bit rates based on codecs that are commonly used by popular music streaming services. While the encoded files were presented via standard Samsung in-ear headphones, the everyday listening situation was simulated by using binaural recordings of a shopping mall soundscape that was simultaneously presented via Stax electrostatic headphones. In a control condition no soundscape was used. The stimuli were rated by 30 participants in a MUSHRA listening test...

A synthesis and analysis framework for wind instrument sounds based on the digital pulse forming principle

A digital real‐time‐capable analysis‐ and synthesis‐system for wind instrument sounds, based on the pulse forming theory, has been developed. The rediscovered model for the sound generating process of wind instruments rests upon the idea, that wind instrument sounds can basically be put down to its excitation impulses, which independently of the fundamental always behave according to the same principles. First realised in the analogue wind instrument synthesizer Realton Variophon (1975), the sound synthesis method has currently been transferred onto a digital platform [supported by the German Research Foundation]. Instrument specific algorithms control the pulse width and shape according to the applied pitch and dynamic values. That way subtle sound nuances that can be produced on acoustic wind instruments as well as real timbre modulation may be synthesized by just modifying a single parameter (i.e. breath pressure). In order to validate the performance of the developed framework, several perception expe...

Dynamic Excitation Impulse Modification as a Foundation of a Synthesis and Analysis System for Wind Instrument Sounds

The Variophon is a wind synthesizer that was developed at the Musicological Institute of the University of Cologne in the 1970/80ies and was at that time based on a completely new synthesis principle: the pulse forming process. The central idea of that principle is that every wind instrument sound can basically be traced back to its excitation pulses, which independently of the fundamental always act upon the same principles. In a recent project, supported by the German Research Foundation (DFG), the synthesis method of excitation impulse modification has been transferred to a digital platform.