Test Bench: The New Beyma CD-314Nd/TI Compression Driver and Horn

July 9 2025, 10:10
Acustica Beyma, the established manufacturer from Valencia, Spain, continues to expand its range of products from solid foundations in professional audio, now also to emerging installation and even high-fidelity applications, while implementing a solid environmental stance. Beyma has accelerated its R&D activities, and this CD-314Nd/TI compression driver and horn is one example of those efforts.
 
Beyma_CD-314NdTI-CompDriver-Horn-TWeb
Photo 1: This is the new Beyma CD-314Nd/TI compression driver accompanied by the new Beyma 60°×40° TD-1464P 1.4” throat horn.
I admire Beyma’s environmental stance as a corporation. In 2007 the company installed a large array of solar panels and runs the majority of its facility from solar-generated electricity. The driver Beyma sent for this Test Bench  is a new model from its extensive line up of 33 compression drivers — the 1.4” throat high power handling CD-314Nd/TI compression driver accompanied by the new Beyma 60° × 40° TD-1464P 1.4” throat horn (Photos 1-3). Designed for use with 1.4” throat horns the CD-314Nd/TI’s applications include use as a high power handling compression driver in mid- to large-venue PA systems.
 
Photo 2: Here is a closer look at the the new Beyma 60°×40° TD-1464P 1.4” throat horn.
Photo 3: One of the features of the CD-314Nd/TI driver includes titanium diaphragm and voice coil assembly.
Features for the new Beyma CD-314Nd/TI compression driver include a 1.4” (36mm) throat diameter driven by a 76.2mm (3”) diameter copper-clad aluminum wire (CCAW) voice coil wound on a non-conducting Nomex former. This assembly drives the field replaceable F.E.M. optimized Titanium diaphragm and surround. Other features include a lightweight computer FEA-optimized neodymium ring magnet motor structure (net weight is 4lbs) that includes a copper shorting cap (Faraday shield) and the patented Deplocex thermal technology for lower power compression and increased power handling.

Other specifications detail a 90W AES power handling crossed above 0.8kHz, 130W AES above 1.2kHz (180W program above 0.8kHz, 260W program above 1.2kHz), a 0.8kHz recommended crossover frequency (with a minimum 12dB/octave high-pass network), a 1W/1m 110.0dB sensitivity (with the Beyma TD-1464P horn), an aluminum cover sporting a new 3D logo (Photo 4), plus standard solderable terminals.
 
Photo 4: The driver is marked with Beyma's with a new 3D logo.
Along with the CD-314Nd/TI, Beyma sent me the 1.4” throat injection-molded reinforced polycarbonate TD-1464P 60° × 40° horn with an 800Hz cut-off frequency and a 12.7 directivity index. The horizontal and vertical directivity maps can be seen in Photo 5 and Photo 6, respectively. This horn is also conveniently marked so the user will get the orientation correct, as shown in Photo 2.
 
Photo 5: The horizontal directivity map for the TD-1464P horn.
Photo 6: The vertical directivity map for the TD-1464P horn.
Testing began as usual using the legacy LinearX LMS analyzer to produce the 300-point stepped sine wave impedance plot shown in Figure 1, with the solid black curve showing the CD-314Nd/TI mounted on the TD-1464 horn and the dashed blue curve representing the compression driver without the horn. With nominal 8Ω impedance CD-314Nd/TI and TD-1464P combination has a 4.36Ω Re and minimum impedance of 5.55Ω at 5.87kHz.
 
Figure 1: Beyma CD-314Nd/TI free-air impedance plot.
For the first group of SPL measurements, I free-air mounted the Beyma CD-314Nd/TI and TD-1464 combination without an enclosure. Then, I measured both the horizontal on- and off-axis at 2.0V/0.5m (normalized to 2.83V/1m) from 0° on-axis to 60° off-axis, using the Loudsoft FINE R+D analyzer and the GRAS 46BE microphone (supplied courtesy of Loudsoft and GRAS Sound & Vibration).

Figure 2 displays the on-axis frequency response of the compression driver/horn, which shows a smooth ±2.55dB response from 600Hz to 10kHz. Figure 3 depicts the 0°-60° on- and off-axis response in the horizontal plane. Figure 4 shows the normalized horizontal plane response. Next, using the CLIO Pocket analyzer and accompanying CLIO microphone (courtesy of Audiomatica SRL), I generated the 180° horizontal polar plot (measured in 10° increments with 1/3 octave smoothing applied) shown in Figure 5.
 
Figure 2: Beyma CD-314Nd/TI on-axis frequency response.
Figure 3: Beyma CD-314Nd/TI horizontal on- and off-axis frequency response (0°=black; 15°=blue; 30°=green; 45°=purple; 60°=blue).
Figure 4: Beyma CD-314Nd/TI normalized horizontal on- and off-axis frequency response (0°=black; 15°=blue; 30°=green; 45°=purple; 60°=blue).
Figure 5: Beyma CD-314Nd/TI 0°-180° horizontal plane polar plot (in 10° increments).
For the vertical plane, Figure 6 illustrates the 0°-60° on- and off-axis response. Figure 7 depicts the normalized vertical plane response, and Figure 8 shows the the 180° vertical polar plot (measured in 10° increments with 1/3 octave smoothing applied), generated by the CLIO Pocket analyzer.
 
Figure 6: Beyma CD-314Nd/TI vertical on- and off-axis frequency response (0°=black; 15°=blue; 30°=green; 45°=purple; 60°=blue).
Figure 7: Beyma CD-314Nd/TI normalized vertical on- and off-axis frequency response (0°=black; 15°=blue; 30°=green; 45°=purple; 60°=blue).
Figure 8: Beyma CD-314Nd/TI 0°-180° vertical plane polar plot (in 10° increments).
For the last of the SPL measurements, Figure 9 depicts the two-sample SPL comparison showing the two Beyma CD-314Nd/TI and TD-1464P compression driver samples to be closely matched within 0.5dB to 2.1dB or less throughout the driver’s operating range.
 
Figure 9: Beyma CD-314Nd/TI two-sample SPL comparison.

For the remaining sequence of tests, I again set up the Listen AudioConnect analyzer and ¼” SCM microphone (provided courtesy of Listen, Inc.) to measure distortion and generate time-frequency plots. For the distortion measurement, I mounted the Beyma CD-314Nd/TI and TD-1464P combination in free-air in the same manner as was used for the frequency response measurements, and set the SPL to 104dB at 1m (1.66V) determined by using a pink noise stimulus generator and internal SLM in the SoundCheck V21 software, and then the distortion measured with the Listen Inc. microphone placed 10cm from the mouth of the horn. This produced the distortion curves shown in Figure 10.
 
Figure 10: Beyma CD-314Nd/TI SoundCheck distortion plots.
After completing this test protocol, I then set up SoundCheck 21 to generate a 2.83V/1m impulse response curve for this driver/horn combination and imported the data into Listen’s SoundMap Time/Frequency software. Figure 11 shows the resulting cumulative spectral decay (CSD) waterfall plot. Figure 12 shows the Short Time Fourier Transform (STFT) plot.
 
Figure 11: Beyma CD-314Nd/TI SoundCheck CSD waterfall plot.
Figure 12: Beyma CD-314Nd/TI SoundCheck Short Time Fourier Transform (STFT) plot.
Taking into consideration all the objective measurement data presented, the CD-314Nd/TI compression driver is clearly a well-engineered 1.4” compression driver, exhibiting good performance, outstanding build quality, the kind of power handling required for large-venue PA systems. For more information about this and other Beyma OEM pro sound products, visit www.beyma.com. VC

This article was originally published in Voice Coil, April 2025
 
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About Vance Dickason
Vance Dickason has been working as a professional in the loudspeaker industry since 1974. A contributing editor to Speaker Builder magazine (now audioXpress) since 1986, in November 1987 he became editor of Voice Coil, the monthly Periodical for the Loudspeake... Read more

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