2-1/2"s possibly a full range type, intended for all freq range between that of the 6-1/2"s and the tweeters mounted in the front A-pillars. However, BMW may have them crossed above bass frequency, with no ceiling, in which case they would be serving both mid and treble duties, with the tweeters in front contributing to the highs. Same speaker in the dash as the rear doors. Tweeters are soft dome type.

When I replace all speakers, I will not be using the dash 2-1/2"s, just mids and tweeters (A-pillars) in the front, same story for rear doors. Highs in rear adjusted to not interfere with staging.

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