Couple of thoughts here. First, *most* amplifiers have 2 input connection methods. 1 is "high level" the other is "low level" or RCA. The difference between these is high level accepts the speaker outputs from a head unit where (inside the amp) levels are reduced to the same level needed to supply RCA inputsl. By purchasing an external "low level adapter" like the PAC, you are effectively buying what is already inside the amp. In other words, why are you wasting your money? There is no inherent value in doing that. The only advantage in purchasing the aoem-hon20 is it (might) have the correct adapter to plug directly into the factory radio/harness. Basically, that's $30 to save a few minutes of wire splicing. But if that's what you need, perhaps it makes sense.
They are the OEM, so they should know. Plug configurations are the reason. It's likely the Ridge isn't supported in the PAC product line because vehicle sales volumes are nowhere near Civics, Accords, ETC.
