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SWR sm400/sm400s power discrepency question

I own an swr sm400s and managed to track down a phyical manual for the swr sm400 - knowing of course that this is not for the "s" version (yet knowing it has more similarities that not). Despite being a nerd for printed material and ephemera, I wanted to read about the specs, settings, and reccomendations from the physical - pre fender SWR manual itself.

I have seen the online swr sm400s pdf manual which states that the sm400s is capable of 550 watts bridged at 4 ohms or 250 watts per channel at 4 ohms, or 400 watts bridged at 8 ohms. Conversely, I have read that the original sm400 had less power. I always took this to be the truth and never questioned this until I open the pages of my manual.

Upon reading the newly acquired swr sm400 manual, I found that they claim that the original sm400 (not the "s" as this manual predates that later upgraded model circa 1993) is capable of the exact power specs listed above - mirroring that of the later sm400s. I have read online over and over that the later sm400s was "upgraded" to more power, and that the sm400 had less power, but my question is - has this always been disinformation, and was the original sm400 always just as powerful as the later sm400s despite having differing power transisters (I have read about the move to Sankin power transistors post 1993 for the sm400s and other models)?

I am attaching photos of the sm400 manual that I took this morning. Anyone with experience, oppinions, discrepancies - pleas chime in!

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As a quick aside/addition. Toward the back section of the manual I found a bit that many of us swr users are familiar with. This states that units with a specific serial #s post 1993 have an internal fan. This makes me wonder, did they revise their interpretation of the power that the original sm400 (not the "s") had given the fact that this manual was clearly made during the era when the sm400s was begining to be produced (perhaps alongside the sm400 at the same time - curious about this as well - were they offering the sm400 AND the sm400s at the same time for a while)?

I revognize that this all migh seem somewhat inconsequential, but I have a deep curiosity, interest and fascination with SWR and their amplifiers, and would love to better understand what might be going on here.

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