Mundorf AMT26-Myro-V2 specifications

Category : Speaker chassis

Special OFFICE, which, in cooperation with Michael Weidlich (Fa. Myro ) was developed exclusively for the Myro Time 2 and is only used there. The range of application is slightly higher (cut-off frequency from about 4 kHz) and the geometry of the folds is optimized for the reproduction of high-frequency signals. It was necessary to expand the transmission range compared to the Myro Ocean with the AMT 2540 . The Time 2 should have a flatter profile at the transmission ends in order to optimize the signal / time behavior. For example, a new Mundorf Air Motion Transformer was specially developed. The AMT has a very linear frequency response with a flat, wide rolloff at the upper end of the transmission. Usually, EXTS at the upper transmitting end show membrane resonances and then a steep drop in the sound pressure level. The OFFICE from the TIME does not show that. The wave geometry of the diaphragm is suitable for high frequencies and due to the very effective damping of the diaphragm resonances, the harmonic distortion could be significantly reduced.

How does an AMT work?

From an acoustic point of view, an Air Motion transformer is a parallel connection of several very small radiating surfaces (membrane pockets / folds). Each pocket (fold) is such a partial area. With such a small partial area, the perfect adaptation (radiation impedance) to the air is only achieved in the super high frequency range. The interconnection of many sub-surfaces improves the adaptation, for example, to the extent that we experience it with sound lines or even with the bafflestep of a housing. In simple terms, the pocket geometry determines the upper cut-off frequency of the AMT and the total area determines the radiation resistance. The pocket geometry also has an influence on the high-pass behavior and the resonance of the membrane. In addition, because of their relatively linear impedance frequency response, they do not have a linear phase frequency response, but rather a phase profile that is ahead of the curve according to their high-pass. Air Motion Transformers are usually rather super tweeters with a very low high-pass (resonance damped and corrected), very resilient and strong in sound pressure. A further advantage, in particular in the case of a symmetrical chassis arrangement, is the "adjustable" emission behavior with the aid of the diaphragm geometry. A long (high) narrow AMT bundles vertically more strongly and radiates horizontally wide. A short wide AMT bundles more strongly horizontally and radiates further vertically.

Mundorf AMT 26 Myro V2

Myro Time 2

Measuring range: 400 - 50,000 Hz

Frequency response

There is a clear resonance point of the diaphragm in the range around 2 kHz, which can be corrected very well, as well as the flat, high-pitched low-pass filter. It should be borne in mind that the AMT was developed for a relatively high coupling to two Accuton C50-8-043 midrange domes. Since AMTs are extremely sensitive to the construction of the rear chamber and especially to the insulation materials in it, many materials, blanks and measurement series were required to achieve the course shown above.

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