Uploaded December 2022 | Updated September 2026, 1 week ago
In this video, I describe and show the small stereo line-level adjuster (attenuator/preamplifier/booster) that I use in my home theater to allow easy volume adjustment from next to my recliner chair in my home theater. I mentioned, but did not show, this preamp in my earlier video about the Parasound Zpre3 stereo line-level preamplifier. Since there seems to be essentially no real documentation online about this preamp, I decided to study its circuitry , take detailed external and interior photos, trace the printed circuit board, create a new CAD schematic, measure its audio performance, discuss various claims about its power supply, and make this video documentary.
The new schematic, in PDF format, may be downloaded from this webpage:
serpentwebsite.com/fileshare.htm
Here is the timeline table of contents for this video:
00:00 Overview
05:14 Internal views
10:23 Schematic overview (new)
11:20 Circuit theory and development of empirical specifications
In this video, I describe and show the small stereo line-level adjuster (attenuator/preamplifier/booster) that I use in my home theater to allow easy volume adjustment from next to my recliner chair in my home theater. I mentioned, but did not show, this preamp in my earlier video about the Parasound Zpre3 stereo line-level preamplifier. Since there seems to be essentially no real documentation online about this preamp, I decided to study its circuitry , take detailed external and interior photos, trace the printed circuit board, create a new CAD schematic, measure its audio performance, discuss various claims about its power supply, and make this video documentary.
The new schematic, in PDF format, may be downloaded from this webpage:
serpentwebsite.com/fileshare.htm
Here is the timeline table of contents for this video:
00:00 Overview
05:14 Internal views
10:23 Schematic overview (new)
11:20 Circuit theory and development of empirical specifications
