What significant drawback did earlier piezoelectric sensors have that Kistler's IEPE design eliminated?

Answer

Requiring high-impedance cables and separate charge amplifiers

Before Kistler's integrated design, piezoelectric sensors needed high-impedance cables and external charge amplifiers, making them susceptible to noise and environmental interference.

What significant drawback did earlier piezoelectric sensors have that Kistler's IEPE design eliminated?
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