Kestrel-8FE
Celestion CDX1-1747 / LaVoce HD1004 with FaitalPro 8FE200-4
This is the third version of the Kestrel. The Celestion CDX1-1747 with the LaVoce HD1004 remained but the midwoofer is replaced with a FaitalPro 8FE200-4. Of the three, this is the only version with a 4Ω woofer.
 Fig 1 – FaitalPro 8FE200-4 – RAW (Black plot) • Low Pass (Blue plot)
The Black plot in Fig 1 is the RAW response of the FaitalPro 8FE200-4. The Blue plot is with a Low Pass filter with the crossover tweaked slightly.
 Fig 2 – FaitalPro 8FE200-4 Low Pass • CDX1-1747 with HD1004 High Pass
The Red plot in Fig 2 is the CDX1-1747 with the LaVoce HD1004 horn with a high Pass filter. Acoustically, they are crossing at about 1.9kHz.
 Fig 3 – Crossover Summation
The Black plot in Fig 3 is the summation of the High Pass and Low Pass. No cancellations are observed in the crossover region, indicating a proper crossover filters.
 Fig 4 – Kestrel-8FE Frequency Response
Fig 4 is the final frequency response of the Kestrel-8FE. Her response is flat from 1.5kHz to 13kHz (+- 3dB). This response is without smoothing applied.
 Fig 5 – Kestrel-8FE Null Response
Fig 5 is the Null response when the tweeter wires are in-phase. Surprisingly, a deep notch is recorded at 1.6kHz.
 Fig 6 – Kestrel-8FE Waterfall
The Waterfall plot (Fig 6) does not record any audible artifacts.
 Fig 7 – Kestrel-8FE Toneburst Energy Storage
Fig 7 is the Toneburst Energy Storage plot. The artifacts are the light blue slices.
 Fig 8 – Kestrel-8FE Spectrogram
The Spectrogram (Fig 8) shows the artifacts in 2D. From 2kHz onwards, the artifacts are inaudible because they dissipate by 2msec.
 Fig 9 – Kestrel-8FE Step
The Kestrel-8FE Step (Fig 9) shows the acoustic centers of the two drivers are very close. This is an indication of good time alignment.
 Fig 10 – Kestrel-8FE Distortion
The Kestrel-8FE Distortion (Fig 10) shows the 3rd harmonic dominates from 2kHz~5kHz. Fortunately, they are buried -45dB below the fundamental.
 Fig 11 – Kestrel-8FE Excess Group Delay
Fig 11 is the Excess Group Delay of the Kestrel-8FE. Generally, there’s very little fluctuation from 140Hz to 50Hz. The most is 1.5msec at about 53Hz.
Summary
The FaitalPro 8FE200-4 midwoofer did not disappoint. The vocals came out exactly as I had hoped. Clearly defined, transparent and absolutely without any veil. Furthermore, it is not shouty and has no nasalness, therefore no EQ needed to get rid of that offending region.
Of all the Kestrels, this is the one. The previous one with the Celestion TF0818 is very close but the midrange in this Kestrel-8FE stands out better.
The treble is superb, as expected.
Unless otherwise stated, all measurements were made in Full Space (4pi). Mic at 36 ins, tweeter axis. Impulse Window=5ms. No smoothing applied. |
