I would trust the Philharmonic HT Center to have the clearest intelligibility, the single most important feature of a center speaker along with high power handling, as stated in the speaker descriptions first sentence.
I was lucky to find a used Salk Veracity HT2C, the center speaker matches my HT2-TL speakers. The HT2C is my third center speaker, along the way I found out intelligibility is the most important. When properly set up, almost 100% of the dialog comes from the center speaker. The center has to have fast, precise drivers and the frequency response has to be rolled off fairly high or males voices become too deep and boomy at high volumes. A sealed speaker sounds best, no ports allowed for the clearest dialog, the Philharmonic HT Center is a sealed design.
Dolby specifications for center, surround and Atmos speakers roll off low frequencies around 80 Hz. Surround processors are designed to send all low frequencies to the sub. The small mid-woofers in center speakers can't handle the elevated bass in action movies without compromising the dialog. And a home theater receiver is less stressed if it doesn't have to send low bass to 5 or 7 speakers.
Even though my home theater has 1850 watts (high current AB amps from AVA and Adcom), I still roll off my center speaker at 80 Hz, without trying to reproduce the lowest frequencies my setup can go as loud and clear as a premium movie theater. A REL G1 sub handles the bass into the teens. But I hardly ever listen that loud.
