Heil AMT Tweeter
There are different models of AMT (Air Motion Transformer) tweeters by Heil. The one featured here was used in the ESS Performance Series PS-920 and PS-820 loudspeakers. According to Heil’s brochure, this tweeter was crossed at 2kHz. All the measurements below were made without any crossover unless otherwise stated.
Heil AMT in a 7 Liters Box (Baffle Width = 6.75″)
Fig 1 – Black plot = RAW. Red plot = 2.6kHz (24dB/oct).
RAW Heil AMT Cumulative Spectral Decay (Baffle Width = 6.75″)
Fig 2 – Rise Time = 0.1ms, Window = 1.3ms ( 769Hz ), Time Range = 1.0ms.
RAW Heil AMT Toneburst Energy Storage (Baffle Width = 6.75″)
Fig 3 – Heil AMT Toneburst Energy Storage.
RAW Heil AMT Spectrogram (Baffle Width = 6.75″)
Fig 4 – Heil AMT Spectrogram
RAW Heil AMT Step Response
Fig 5 – Step Response (No Crossover)
Heil AMT Impedance
Fig 6 – Heil AMT Impedance Sweep
February 15, 2019HIFI DRIVERS