Marantz Model 9 ~ Deep Dive ~ Restoration Review & Bench Tests

In this video I review some history behind the iconic Marantz 9 amplifier along with a front panel control overview, a detailed look at the restoration that I performed, along with bench tests to verify that restoration.

00:00 Introduction
00:46 History
03:59 Design Elements
05:20 Front Panel Controls
09:11 Adjustments
12:43 Tubes and Triode/Ultralinear Switch
15:34 Alternate Marantz 9 Versions
16:30 Restoration Review
36:19 Bench Testing
37:00 Ultralinear Output Power Test
39:18 Triode Mode Output Power Test
40:29 Frequency Response Bode Plot
45:52 Alternate Ways of Looking At Frequency Response
48:23 Phase Switch
49:20 THD Measurements

References:
https://audiohistory.com/files/documents/marantzhistory.pdf
https://www.hifiengine.com/
https://worldradiohistory.com/Archive-All-Audio/HiFI-Stereo-Review.htm