A new sound world emerges when the mute slides on: An Alter mute sounds special, not just quieter.  Players rave about them, Emma’s favourite testimonial from a British violinist: "So good I'd like to eat it" Alter mutes are used worldwide, in both leading orchestras and period-instrument ensembles.
The three pronged mutes are requested by Orchestra of the Age of Enlightenment as standard for use in their string sections. They're based on historical mute designs from the 18th century.