In this blog post I test the Beyma 15LX60V2 15" woofer.
The published data can be downloaded here.
Features
- 4” DUO double layer in/out voice coil
- High sensitivity: 98 dB (1W / 1m)
- Extended controlled displacement: Xmax ± 9 mm
- 47 mm peak-to-peak excursion before damage
Published Response
The published data shows a very flat impedance through it's passband with breakup occurring at 1.1kHz. The frequency response is very linear as well.
With the driver mounted in my 90L test cabinet I was able to acheive similar results as the anechoic data from Beyma. The red curve is the raw data while the blue curve is with my passive low pass filter in place for a 600Hz crossover.
Showing the same data but with the vertical scale reduced to the standard 50dB is shown below.
I then measured the impedance and we can see that my 90L cabinet is tuned to 33Hz. We see the first breakup occurring at 1kHz which is nearly an octave above my crossover point.
Distortion
With my low pass filter in place, I measured harmonic distortion at 85,95, and 105dB at 1m. Distortion never surpasses the 1% even at 105dB. At normal listening levels (85dB) we see H2 at 0.05%.
I tested intermodulation distortion using a multi-band multitone test signal ranging from 50Hz to 2kHz at 85,95, and 105dB at 1m. Distortion is -62dB (0.08%) at 100Hz.
95dB shows -52dB (0.25%) at 100Hz.
105dB shows -42dB (0.80%) at 100Hz.
Subjective Listening
I rigged up a passive crossover in a 2-way configuration and evaluated the woofer in mono. Below is the resulting frequency response. I have a small -4dB dip at the crossover region but I am find with this. I also implemented a small +2dB HF shelf starting at 4kHz which I found subjectively to sound nice, bringing out some upper treble detail and balancing out the narrowing directivity of the horn.
Summary of Listening Impressions
- Excellent output capability (104dB at my listening chair 2m away)
- Clean output across the spectrum, especially in the critical 300Hz-600Hz region where soundstage depth can suffer. Not the case here.
- Very good dynamics providing good mid-bass punch that you feel through your body.
- Low bass (50Hz-100Hz) is textured and refined, with no hint of sloppiness.