Needs repeating with a proper milli-ohm set up rather than DVM 0.1 ohm
resolution or preferably actively with some higher current through it.
Probably really only becomes manifest close to the current carying limit of
the original round wire, replicating the problem in speaker voice coil
production and use.

Tried about 1m of 0.09mm (including varnish) wire around a 15mm a side flat
and squashed between 2 flats in a protected vice and made no difference to
4.0 ohm, despite 32 theoretical, not obvious, flats.
Repeated with just a single 15mm length of that 1m long wire, reducing 0.09
mm to about 0.03 mm , and repeated further along, so 2 squashed bits of 15mm
.. May have increased to about 4.05 ohm overall but not as obvious a change
as I was expecting.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
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