We offer upgrades if we discover ways to improve existing products significantly. The latest enhancements are available here.
We do not recommend modifying a model yourself with non-standard parts, as it will invalidate the warranty and likely make your speakers underperform. Designing PMC speakers takes skilled R&D engineers a great deal of time, using the best equipment at their disposal and considering all factors. Judiciously replacing components can upset the balance of a carefully designed speaker.
If you are looking to service a product, please get in touch with service@pmc-speakers.com