That is a good point. Because of the transformers on the speakers saturating at low frequencies as I said above you want to high pass and 80Hz is a good number. The better and heavier the transformers are the better the low frequency response so if they used really good transformers on the speakers and an amp that is direct drive with no output transformer you could get decent low end and not have to (or want to) use any high pass. But usually you find that most ceiling speakers are el cheapo and only go down to around 100Hz.

Those Crown Com-Tech amps are top of the line and direct drive 70.7V so you are in good shape there.

-Hal

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