Since incorporating my ST-120 into my combo HT/Audiophile system 5 years ago, I've been using a Niles 2 amp/1 speaker switch to swap between my Marantz AVR front amps and the ST-120. The Niles works great, but it does not have no-load protection for the unused amp and I've been worried about accidentally running the ST-120 unloaded.
I've also been on the lookout for an external VU meter and came across what, so far, seems to be a reasonably-priced and well-built (albeit Chinese) device that provides two sizable and dimmable VU meters plus amp/speaker switching to boot! It even comes with a remote. Best of all, it provides no-load protection for the ST-120.
Long-time member here. No affiliation with the product. If you are interested here's a link: Dual Analog VU Meter 2-Way Amplifier/Speaker Audio Switcher Box DB Panel Display https://a.co/d/bNP2tQL
I've also been on the lookout for an external VU meter and came across what, so far, seems to be a reasonably-priced and well-built (albeit Chinese) device that provides two sizable and dimmable VU meters plus amp/speaker switching to boot! It even comes with a remote. Best of all, it provides no-load protection for the ST-120.
Long-time member here. No affiliation with the product. If you are interested here's a link: Dual Analog VU Meter 2-Way Amplifier/Speaker Audio Switcher Box DB Panel Display https://a.co/d/bNP2tQL