Recording & Production

Thursday, October 19, 11:15 am — 12:30 pm (Rm 1E12)

Chair:
Palmyra Catravas, Union College - Schenectady, NY, USA

EB02-1 Engineered Remote-Sensing Audio Power Amplifier for High-Fidelity Applications—Peter Horowitz, Fourth Dimension Engineering - Columbia, MD, USA
The objective of this work is to minimize the deleterious effects of loudspeaker cable impedance when driving dynamic loudspeakers, accomplished primarily with a mathematical feedback analysis on the prominent role of the cables themselves within the audio baseband feedback loop. Presented are the measured system waveforms, along with computed root loci and transfer functions of a proof-of-principle remote-sensing (4-wire) 80 watt audio power amplifier. A single baseband feedback loop compares the incoming audio information (voltage) to the resultant voltage across the loudspeaker electrical terminals and minimizes the difference. Measured waveforms demonstrate notably superior replication of incoming information at the loudspeaker terminals over the audio band. The system is empirically robust for a wide range of dynamic loudspeaker and cable systems without any need for electronic adjustment. For example, with 35 meter 15/22 gauge cabling, a bandwidth of 72kHz, dynamic range of 110dB, phase linearity of <0.5°, and low impedance drive levels of <0.2O at the loudspeaker terminals are readily achieved simultaneously. 

EB02-2 Building a Globally Distributed Recording Studio—John Fiorello, RecordME - Torrington, CT, USA
The internet has played a significant role in changing consumer behavior in regards to the distribution and consumption of music. Record labels, recording studios, and musicians have felt the financial squeeze as physical media delivery has been depreciated. However, the internet also enables these studios, musicians, and record labels to re-orient their business model to take advantage of new content creation and distribution. By developing a hardware appliance that combines high-resolution audio recording and broadcasting with real-time, two-way video communication across the web, we can expand the geographic area that studios can serve, increase revenue for musicians, and change the value proposition traditional record labels have to offer. 

EB02-3 Simultaneous Audio Capture at Multiple Sample Rates and Formats for Direct Comparison and Evaluation—Jordan Strum, ProStudioMasters - Montreal, QC, Canada; Richard King, McGill University - Montreal, Quebec, Canada; The Centre for Interdisciplinary Research in Music Media and Technology - Montreal, Quebec, Canada; Oles Protsidym, ProStudioMasters - Montreal, QC, Canada; Ieronim Catanescu, McGill University - Montreal, QC, Canada
In order to evaluate differences among recording formats and resolutions over a variety of classical, jazz, and popular musical material, a unique collection of audio assets was recorded. Live performances were captured using a single pair of microphones, positionally adjusted for each sound source. Preamplifier outputs were routed to 11 identical recording interfaces capturing various PCM and DSD formats simultaneously with 3 analogue tape recorders, the contents of which were then transferred to the above digital formats. These assets will be used to compare differences among recording formats and resolutions using identical performances, and to provide source material for listening tests as well as further research. The design and execution of this project will be discussed. 

EB02-4 Undergraduate Curricular Development at the Electrical Engineering/Music Interface at Union College—Palmyra Catravas, Union College - Schenectady, NY, USA
Curricular development at the interface of electrical engineering and music will be described, with a focus on the pedagogical use of audio and acoustics to reinforce basic fundamentals in electrical engineering. The effort, which has taken place over more than a decade, seeks to reinforce the foundation provided by the traditional, rigorous engineering curriculum at Union College, an undergraduate liberal arts college in upstate NY. A related specialized research laboratory – Phasor Lab – is located in the Peter Irving Wold Science and Engineering Center at Union. 

EB02-5 Recording, Mixing and Mastering of Audio Using a Single Microphone Array and Audio Source Separation Algorithms—Jakub Zamojski, Zylia sp. z.o.o. - Poznan, Poland; Piotr Makaruk, Zylia - Poznan, Poland; Lukasz Januszkiewicz, Zylia Sp. z o.o. - Poznan, Poland; Tomasz Zernicki, Zylia sp. z o.o. - Poznan, Poland
The authors present a new way of recording of music bands using a single microphone array and audio source separation algorithms. In contrast to the traditional recording process, this novel approach allows for capturing all of musical instruments simultaneously using only one recording device, avoiding a multiple sets of spot microphones, cables, and D/A converters. Moreover, using a single microphone array and dedicated algorithms gives the sound engineer a unique set of “audio processing tools” that can be used in the post-production stage. This paper describes step-by-step a recording process of a music band playing ukulele using a 19-capsules spherical microphone array and dedicated software. The process includes the following stages: recording, sound source separation, mixing, and mastering.