Feature-wise the main difference is that it features a 3.5-mm audio connector (phone connector) for audio input which enables it to cast Chromecast audio, which uniquely makes it the only commercial hardware appliance that features Chromecast audio casting.
Please consider designing/making an Onju Voice PCB variant for the "Google Home Max" speaker.
https://en.wikipedia.org/wiki/Google_Nest_(smart_speakers)
https://support.google.com/googlenest/answer/7072284
Bet quite a few people like myself also own a few of these original Google Home speakers and are interested in converting them.
https://www.dimensions.com/element/google-home-max
Feature-wise the main difference is that it features a 3.5-mm audio connector (phone connector) for audio input which enables it to cast Chromecast audio, which uniquely makes it the only commercial hardware appliance that features Chromecast audio casting.
FCC ID A4R-H0B
https://fccid.io/A4R-H0B
https://fcc.report/FCC-ID/A4R-H0B/3627625
https://apps.fcc.gov/oetcf/eas/reports/ViewExhibitReport.cfm?mode=Exhibits&RequestTimeout=500&calledFromFrame=N&application_id=ZJOgPO3nv280csenI2Dd0Q%3D%3D&fcc_id=A4R-H0B
FYI, other than on FCC, I could not find any free teardown information about the "Google Home Max" speaker model.
There is a paid version of a teardown report though:
https://www.reverse-costing.com/teardowns/pe_googleteardown-home-max-h0b-0/#features