In article , Arny Krueger
wrote:

[snip]

There's an old JAES paper by Greiner of the University of Wisconson that
charted nonlinear distoriton due to fuse thermal effects.

Ah! Thanks for that info. I'll do a search on the CDROM set of papers I
have and see if I can unearth a copy. May save me wondering or having to
re-do measurements that have already been done! I had the feeling that
surely someone *had* done this, but could not recall ever seeing it.

My assumption until quite recently was that no-one would now use fuses in
the o/p of a power amp as the effect would depend upon the speaker - a
factor outwith the control of the amplifier designer. :-/

Speaker voice coils do this as well.

Although I assume (?) that in the short and medium term the thermal time
constants will be longer due to the mass involved. That said, I suppose the
coils dissipate lots more power than the fuse! :-)
[snip]

Perhaps ironically, light bulbs have their own time/resistance/current
nonlinearity problems.

Indeed, In fact one of our 1st/2nd year experiments used to be to use an
incandescent lamp to do some measurements on Stephan's Law, and this used
the rise in bulb resistance to determine the temperature of the bulb as a
function of the applied power. The snag with doing this with fuses is their
tendency to 'evaporate' half-way through a measurement unless you are
careful. :-)

Slainte,

Jim

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