The Faital Pro 5PR120 is a high sensitivity and high-power handling 5” midrange driver, built on a proprietary six-spoke cast-aluminum frame, with four vents below the spider mounting shelf, and additional cooling provided by a pole vent. It features a curvilinear inverted single piece “bowl” shaped paper cone and black anodized aluminum dust cap. The motor is a FEA-optimized neodymium ring, and driving the cone is a 32mm voice coil wound with round copper wire on a non-conducting Kapton former.
In terms of features, the 5” 5PR120 is built on a proprietary six-spoke cast-aluminum frame, comprised of moderately narrow (about 16mm) spokes, and four 21mm × 1.6mm vents below the spider mounting shelf (Photo 1). Additional cooling for this driver is provided by a 4.25mm diameter pole vent.
The cone assembly consists of a curvilinear inverted single piece “bowl” shaped paper cone with a 42mm (1.65”) diameter black anodized aluminum dust cap (Photo 2). Compliance is provided by a raised planar EPDM (rubber) surround, with the remaining compliance coming from a 2.8” diameter flat cloth spider (damper) with constant height waves. Voice coil lead wires are a flat ribbon-type cable stitched into the spider on one side of the frame. On the opposite side of the frame, the same flat ribbon tinsel lead wire is stitched into the spider, but not connected to the voice coil, presumably to provide symmetrical weight balance to avoid rocking modes.
The motor is a FEA-optimized neodymium ring magnet type with milled and shaped plates. Driving the cone assembly is a 32mm (1.26”) diameter voice coil wound with round copper wire on a non-conducting Kapton former. Sensitivity is 100dB 1W/1m with power handling rated at 200W (2-hour test according to AES 2-1984 Rev. 2003, obviously also dependent upon whatever high-pass filter frequency is incorporated).
Since this midrange is likely be crossed over at a minimum of 200Hz (the frequency range specified by Faital Pro is 300Hz to 5kHz), I chose not to use the multi-voltage LEAP 5 LTD TSP testing protocol and instead established parameters with a single low voltage four-wire Kelvin (to zero out the test leads DCR) impedance sweep using the legacy LinearX LMS analyzer. The goal here was to establish an enclosure volume to ascertain the impedance resonance frequency and Q. This information is useful if a passive high-pass network is employed, and of course, not relevant if using active filters.
Following my established protocol for Test Bench testing, I no longer use a single added mass measurement and instead use the company’s supplied Mmd data (7.3 grams for the 5PR120). The single impedance sweep for each driver along with the Mmd data was used to produce the TSL parameters for the two Faital Pro 5PR120 samples. Figure 1 shows the 1V free-air impedance curve. Table 1 compares the single sweep TSL data and factory parameters for both Faital pro samples.
LEAP parameter calculation results for the 5PR120 driver correlated well with the Faital Pro factory published Thiele-Small Parameters (TSPs), except for the 2.83V/1m sensitivity, which was higher than the TSP calculated numbers I publish. Like a number of OEMs, Faital Pro uses a formula for Xmax that makes adjustment for the fringe field and adds in the gap/3 to the physical Xmax. I proceeded to set up computer enclosure simulations using the LEAP LTD parameters for Sample 1.
Since this driver will likely have a high-pass filter of at least 250Hz to 300Hz, I only want to establish the F0 and Q for a box volume as reference for a passive network design. Using the LinearX LEAP 5 legacy software’s Quick Design utility, I came up with two volumes—75in3 sealed enclosure and 75in3 vented box timed to 112Hz. However the upper impedance peak for the vented box was somewhat higher in frequency than that of the sealed box resonance (111Hz), so I did not think it would not provide any passive network advantage over the sealed box and was discarded (see Figure 2).
Figure 3 displays the frequency response result for the Faital Pro 5PR120 midrange in the single simulated sealed enclosure at 2.83V. The closed-box alignment produced a 3dB down frequency of 310 Hz, Qtc=0.71. Figure 4 gives group delay curves. Here the F0 and Q data could be used to design an LCR resonance conjugate filter to facilitate a 250Hz to 400Hz passive high-pass filter. For the purposes of this explication, Klippel analysis was not appropriate since this device is not being used in its piston range.
I next mounted the 5PR120 midrange in a foam-filled enclosure that had a 12”×7” baffle and then measured the device under test (DUT) using the Loudsoft FINE R+D analyzer and the GRAS 46BE microphone (courtesy of Loudsoft and GRAS Sound & Vibration) both on- and off-axis from 200Hz to 20kHz at 2.0V/0.5m, normalized to 2.83V/1m using the cosine windowed FFT method. All these SPL measurements also included a 1/6 octave smoothing. (This is done to match the resolution of the 100-to 200-point LMS gated sine wave curves that I’ve been using in the column for several years.)
Figure 5 gives the Faital Pro 5PR120 on-axis response indicating a moderately smooth rising response that is ±2.5dB from 200Hz to 8kHz with breakup modes at 10kHz and 14.8kHz. Figure 6 displays the on- and off-axis frequency response at 0, 15, 30, and 45 degrees. The -3dB at 30 degrees with respect to the on-axis curve occurs at 2.8 kHz, so a low-pass cross point in that vicinity should be work well to achieve a good power response.
Figure 7 gives the normalized version of Figure 6, while Figure 8 displays the CLIO horizontal polar plot (in 10° increments with 1/3 octave smoothing) for the Faital Pro paper cone midrange. And finally, Figure 9 gives the two-sample SPL comparisons for the Faital Pro 5PR120 midrange driver, showing a close match between 0.25dB to 1.2dB up to 6kHz.
For the remaining series of tests on the Faital Pro 5PR120 midrange transducer, I initialized the Listen SoundCheck AudioConnect analyzer and 1/4″ SCM microphone (graciously supplied by the folks at Listen, Inc.) to measure distortion and generate time frequency plots. For the distortion measurement, I rigidly mounted the 5” driver in free air and set the SPL to 104dB at 1m (7.4V) using a pink noise stimulus. Then, I measured the distortion with the Listen microphone placed 10cm from the driver. This produced the distortion curves shown in Figure 10.
Next, I employed the SoundCheck software (V21) to get a 2.83V/1m impulse response for this driver and imported the data into Listen’s SoundMap Time/Frequency software. Figure 11 shows the resulting cumulative spectral decay (CSD) “waterfall” plot and Figure 12 shows the Short Time Fourier Transform (STFT) plot.
Looking at the data I collected for the new Faital Pro midrange, the performance looks good and provides sufficient power handling for pro sound applications. For more information, visit www.faitalpro.com. VC
This article was originally published in Voice Coil, February 2025
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