AES Dublin 2019
Paper Session P22
P22 - Physical Systems and Circuits
Saturday, March 23, 14:00 — 15:00 (Meeting Room 2)
John Robert Emmett, Nostairway Creative - Twickenham Studios, UK
P22-1 Statistical Analysis of Audio Triode Tube Properties Based on an Advanced Physical Device Model—Toshihiko Hamasaki, Hiroshima Institute of Technology - Hiroshima, Japan; Reo Sasaki, Hiroshima Institute of Technology - Hiroshima, Japan; Masaki Inui, Hiroshima Institute of Technology - Hiroshima, Japan
The timbre of tube amplifier has been considered to depend not only on the tube type but also on the tube manufacture and its individual difference as well. However, quantitative difference of tube properties of manufacture has not been clarified yet. In this study the manufactures differences of triode tube 12AX7/ECC83 are analyzed statistically by an advanced physical device model. The model parameter values are extracted from measured family curves of 60 devices in total for 5 major tube manufactures for a guitar amplifier. The characteristics of each manufacture tube are clarified by an average and a dispersion of respective parameter value set. Furthermore, the root cause of the significant manufacturing process instability is identified based on the correlation of all combination of parameters for the first time. The tube properties of 5 manufactures are divided into 3 groups by clustering analysis using cosine similarity on the vector of parameters.
Convention Paper 10213 (Purchase now)
P22-2 A Novel Digital Radio-Frequency Capacitor Microphone with Gain Rangin—Lars Urbansky, Helmut-Schmidt University - Hamburg, Germany; Udo Zölzer, Helmut-Schmidt-University Hamburg - Hamburg, Germany
Most capacitor microphones use an audio-frequency (AF) implementation. In an AF circuit, a capacitor is charged with a constant bias voltage leading to a high-impedance circuit. In contrast, by using a radio-frequency (RF) approach, the capacitor is operated on a higher frequency band which reduces the circuit’s impedance. However, state of the art RF microphones are entirely analog. Thus, a novel digital RF condenser microphone system is proposed. Furthermore, it is extended by a corresponding gain ranging approach. The expected advantages are a further improved demodulation linearity due to a digital demodulation and a circumvention of analog disadvantages due to the smaller required analog circuit. Additionally, because of the analog bandpass signal, it is expected to utterly bypass the electrical low frequency 1/f noise.
Convention Paper 10214 (Purchase now)