Genelec themselves does not mention in their documentation that break-in/burn-in is needed. One of the first thing I did with my two 2.1 Genelec systems was to use GLM to calibrate them, and no way I'm going to wait a month or so before doing that.
Here is a seven year old
thread on the Genelec forum asking if burn-in is needed for the 8351, and Genelecs answer (
@Ilkka Rissanen ) is:
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Hello,
No burn in is required nor does it bring you any noticeable performance / sound quality gains. The only thing that changes slightly is the woofer's suspension compliance (the suspension loosens up a bit) which makes the bass sound a little bit more emphasized (than right out of the box), but we are talking about very small differences here. And in any case, this will happen naturally during the few first hours of listening. New GLM calibration is not required or needed.
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