Hello,  I have here some of those gong spirals made from steel wire.
These are for a large clock and they are struck with a leather-faced
hammer.  Basically, these would operate on the same principle as a steel
bar xylophone or the tooth of a music box.

The ones I have here seem to have gone off kilter in that they sound
like someone is throwing coal onto a shovel. :-)  There is only a
horrible "dish' sound instead of a longer lasting "dongggg" sound.
There is nothing physically wrong with them -- they are clean, no
cracks, nothing loose.  So my question is why some old steel things
seem to go dead like this and if there is a way to rejuvenate them,
maybe by heating or something?

How do you folks rejuvenate dead music box combs, for example, or do
those not get this problem?

Kind regards,
Bernt Damm
Sydney