Различные версии:
Display models were manufactured that have clear Plexiglas enclosures (versus the solid wood with fiberglass enclosures) in order to demonstrate the inside of the speaker to customers in retail stores. Though they look interesting, they have a thinner, lower quality sound output compared to the wooden enclosure[citation needed].
Different versions of the HPM-100 were manufactured with different crossovers. The original “A” crossovers were rated at 50 watts with a peak power of 100 watts. However, later “B” and “C” models, manufactured from circa 1977 on, used a more accurate, less conservative power rating of 100 watts with a peak power of 200 watts. HPM-100s that were manufactured with the “B” and “C” crossovers also contained an accent ring around the air hole purely for aesthetics.
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