SLIC Audio Filter and Mute Circuit

From a channel Lumen includes in full: This is a small, honest electronics channel. Its uploads are repair walkthroughs, circuit explanations (DDS, LFSR, op amp design, Twin T filters) and tool tutorials (LTSpice, ATTiny bootloaders), all delivered plainly with no hype or clickbait. The transcripts confirm a clear intent to teach diagnosis, design reasoning and repair technique. The only off-mission items are product-style teardowns and project-update logs, and title patterns exclude those.