Everything for Electronics
Nuts & Volts Magazine (January 2018)

Speaker Protection and Muting with an Optical Coupler

By Vasile Gorcea    View In Digital Edition  

Vintage amplifiers may sound great, but in many cases they lack any form of output protection. In the event of a catastrophic output failure, some amps deliver the full power supply rail voltage to the speakers! This circuit not only protects your speakers from amp failure, but also eliminates the dreaded “turn on thump” some classic solid-state amplifiers exhibit.


Read This Article!
If you’re a subscriber and your subscription includes this issue of Nuts & Volts, you can read this article in our digital edition by clicking the blue icon in the upper right corner. Use the email address associated with your subscriber services account to login.

If you're a member of our Preferred Subscriber Network, not only will the magic blue icon let you read this article, but EVERY article in EVERY issue is yours to enjoy! Over a decades worth of content is stored in our digital archive!

If you’re not a subscriber, you can still view a few sample pages of our digital edition or subscribe here for full digital access and/or print delivery. Also, as you browse around our site, you will find selected articles have been posted in their entirety for you to enjoy.



What’s in the zip?

Parts List
PCB File