The Null Piece and Reality Check

Two frameworks are described, within the larger framework of Pure Data, that aim to facilitate the creation and preservation of electronic music that is performed live in real time. These are not part of Pd itself, because they are more directly tailored to a specific application space than Pd should be. They are nonetheless designed, like Pd, to minimize any unnecessary stylistic imposition on creators of electronic music. The Null Piece is a starting point for building live performance patches. It provides basic audio routing and parameter control while leaving other choices as free as possible. Reality Check is an attempt to aid in the long-term maintenance of a musical realization by verifying whether a piece still runs as intended despite the inevitable evolution of hardware and software

Expediting TTS Synthesis with Adversarial Vocoding

Recent approaches in text-to-speech (TTS) synthesis employ neural network strategies to vocode perceptually-informed spectrogram representations directly into listenable waveforms. Such vocoding procedures create a computational bottleneck in modern TTS pipelines. We propose an alternative approach which utilizes generative adversarial networks (GANs) to learn mappings from perceptually-informed spectrograms to simple magnitude spectrograms which can be heuristically vocoded. Through a user study, we show that our approach significantly outperforms na\"ive vocoding strategies while being hundreds of times faster than neural network vocoders used in state-of-the-art TTS systems. We also show that our method can be used to achieve state-of-the-art results in unsupervised synthesis of individual words of speech.Comment: Published as a conference paper at INTERSPEECH 201

RealTime Audio Analysis Tools for Pd and MSP.”

Abstract Two objects," which run under Max MSP or Pd, do di erent kinds of real-time analysis of musical sounds. Fiddle is a monophonic or polyphonic maximum-likelihood pitch detector similar to Rabiner's, which can also be used to obtain a raw list of a signal's sinusoidal components. Bonk does a bounded-Q analysis of an incoming sound to detect onsets of percussion instruments in a way w h i c h outperforms the standard envelope following technique. The outputs of both objects appear as Max-style control messages. Tools for real-time audio analysis The new real-time patchable software synthesizers have nally brought audio signal processing out of the ivory tower and into the homes of working computer musicians. Now audio can be placed at the center of real-time computer music production, and MIDI, which for a decade was the backbone of the electronic music studio, can be relegated to its appropriate role as a low-bandwidth I O solution for keyboards and other input devices. Many other sources of control input" can be imagined than are provided by MIDI devices. This paper, for example, explores two possibilities for deriving a control stream from an incoming audio stream. First, the sound might c o n tain quasi-sinusoidal partials" and we m i g h t wish to know their frequencies and amplitudes. In the case that the audio stream comes from a monophonic or polyphonic pitched instrument, we w ould like t o b e a b l e t o d etermine the pitches and loudnesses of the components. It's clear that we'll never have a perfect pitch detector, but the fiddle object described here does fairly well in some cases. For the many sounds which don't lend themselves to sinusoidal decomposition, we can still get useful information from the overall spectral envelope. For instance, rapid changes in the spectral envelope turn out to be a much more reliable indicator of percussive attacks than are changes in the overall power reported by a classical envelope follower. The bonk object does a bounded-Q lterbank of an incoming sound and can either output the raw analysis or detect onsets which can then be compared to a collection of known spectral templates in order to guess which o f s e v eral possible kinds of attack has occurred. The fiddle and bonk objects are low t e c h; the algorithms would be easy to re-code in another language or for other environments from the ones considered here. Our main concern is to get predictable and acceptable behavior using easy-to-understand techniques which w on't place an unacceptable computational load on a late-model computer. Some e ort was taken to make fiddle and bonk available on a variety of platforms. They run under Max MSP Macintosh, Pd Wintel, SGI, Linux and fiddle also runs under FTS available on several platforms. Both are distributed with source code; see http: man104nfs.ucsd.edu ~mpuckett for details. 2 Analysis of discrete spectra Two problems are of interest here: getting the frequencies and amplitudes of the constituent partials of a sound, and then guessing the pitch. Our program follows the ideas of Noll 69 and Rabiner 78 . Whereas the earlier pitch~object reported in Puckette 95 departs substantially from the earlier approaches, the algorithm used here adhere more closely to them. First we wish to get a list of peaks with their frequencies and amplitudes. The incoming signal is broken into segments of N samples with N a p o wer of two t ypically between 256 and 2048. A new anal

Evaluation of Musical Creativity and Musical Metacreation Systems

The field of computational creativity, including musical metacreation, strives to develop artificial systems that are capable of demonstrating creative behavior or producing creative artefacts. But the claim of creativity is often assessed, subjectively only on the part of the researcher and not objectively at all. This article provides theoretical motivation for more systematic evaluation of musical metacreation and computationally creative systems and presents an overview of current methods used to assess human and machine creativity that may be adapted for this purpose. In order to highlight the need for a varied set of evaluation tools, a distinction is drawn among three types of creative systems: those that are purely generative, those that contain internal or external feedback, and those that are capable of reflection and self-reflection. To address the evaluation of each of these aspects, concrete examples of methods and techniques are suggested to help researchers (1) evaluate their systems' creative process and generated artefacts, and test their impact on the perceptual, cognitive, and affective states of the audience, and (2) build mechanisms for reflection into the creative system, including models of human perception and cognition, to endow creative systems with internal evaluative mechanisms to drive self-reflective processes. The first type of evaluation can be considered external to the creative system and may be employed by the researcher to both better understand the efficacy of their system and its impact and to incorporate feedback into the system. Here we take the stance that understanding human creativity can lend insight to computational approaches, and knowledge of how humans perceive creative systems and their output can be incorporated into artificial agents as feedback to provide a sense of how a creation will impact the audience. The second type centers around internal evaluation, in which the system is able to reason about its own behavior and generated output. We argue that creative behavior cannot occur without feedback and reflection by the creative/metacreative system itself. More rigorous empirical testing will allow computational and metacreative systems to become more creative by definition and can be used to demonstrate the impact and novelty of particular approaches

Four surprises of electronic music

The evolution of electronic music practice over the past half century has not gone precisely as we expected.  In this paper, we describe four respects in which the development of electronic music was either overtaken by unexpected developments, or, itself, headed in new and unexpected directions