Hifi-Mythen: Doppler vs. IMD, schnelle Bässe und Verzerrungen im Allgemeinen

[Dausend Acoustics]

Hallo zusammen,

Purifi hat auf ihrer Homepage ein gute Beiträge zu so manchem Hifi-Mythos, gut aufgearbeitet und leicht erklärt. Schaut mal rein, es lohnt sich

https://purifi-audio.com/tech/

Grüße
Andreas

[quecksel]

Danke für's verlinken, sehr aufschlussreich

"The model reveals that all motor distortion that can’t be explained by BL(x) can be explained by something called Force Factor Modulation. FFM happens when the magnetic field created by the current in the voice coil adds itself to the magnetic field created by the permanent magnet. Ideally, the magnetic flux in the air gap is only determined by the magnet and the geometry. In practice, it varies strongly because of the current in the voice coil. The problem is exacerbated in longstroke drivers because a larger portion of the coil is creating this unwanted magnetic field without actually producing useful drive force. This goes some way in explaining why short stroke, large diameter woofers have such a faithful following."

Aha!

"In modern (i.e. long-stroke) drive units the surround can easily make up 20% of the radiating surface. It would be optimistic in the extreme to expect that a piece of deforming rubber will end up radiating undistorted sound. Indeed, it does not – its distortion contribution exceeds that of the cone by orders of magnitude. Again the distortion is second order in nature and most obvious at low frequencies. But again that introduces intermodulation distortion affecting the entire frequency range of the driver. SRD is the second reason why large diameter, short stroke drivers have a leg-up. The surround simply takes up a smaller percentage of the moving area."

Deswegen also die komisch geformte Sicke.

[3eepoint]

Danke fürs teilen, sehr spannend zu lesen!