This page is in constant evolution…

Amplifiers for Quad:

Amplification for Quads – Very Important Essay

Refurbishment Solutions:

ESL Labs – Held by Arend-Jan, located in the Netherlands

Sheldon’s World: Quad ESL Repair, DIY Speakers, DAC Design – Important Site

They make a speaker kit as well as built units

Useful posts from DIY Sound Group

MT Audio Design: DIY ESL and More

Step buy step guide for refurbishing Quad ESL 57

ESL Repair Website