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.
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