Genesis Technologies 500 loudspeaker Measurements part 2

This suckout can also be seen in the speaker's response averaged across a 30 degree window on the tweeter axis (fig.4), which is a reasonably high 42" from the floor. It looks suspiciously like an acoustic cancellation problem, perhaps from the dipole loading of the midrange unit. I note that KR did find the speaker's balance laid-back; this behavior might well be the cause.

Fig.4 Genesis 500, anechoic response on tweeter axis at 50", averaged across 30 degrees horizontal window and corrected for microphone response, with the complex sum of the nearfield woofer, midbass coupler, and midrange responses plotted below 300Hz.

Higher in frequency, note that the top octave appears rolled-off compared with fig.3. This is because the circular Genesis ribbon tweeter's output starts to fall off at high frequencies at even moderate off-axis angles. Lower in frequency in this graph, the measured nearfield integration of the woofers and the midbass coupler is not perfect, but this could be a measurement artifact. In any case, the flexibility of the 500's woofer crossover and level should allow the speaker's owner to optimally tune it for the most seamless crossover. The woofer frequency control basically tilts the woofers' output above 50Hz, providing a maximum change of around ±6dB in the octave between 100Hz and 200Hz. And again, note the superb low-bass extension. Despite its small footprint, this Genesis offers true 20Hz performance.

Fig.5 shows the effect of the midrange and treble balance controls when set to their maximum and minimum positions, with the on-axis response subtracted. Mild shelvings of the midrange unit's and tweeter's sensitivities by ±1dB are possible. This is a sensible design decision, in my view.

Fig.5 Genesis 500, effect of the midrange and treble controls when set to their maximum and minimum positions, with the on-axis response subtracted (5dB/vertical div.).

The Genesis 500's lateral dispersion (fig.6, actual responses; fig.7, normalized responses) is quite complicated, presumably due to its use of an omnidirectional woofer section, a midbass coupler with a more restricted dispersion, and dipole midrange and HF units. Above 1kHz, the speaker's behavior is indeed dipolar to some extent, though with the sharp notch in the dispersion pattern at 90 degrees off-axis. As mentioned earlier, the tweeter rolls off quite rapidly to the speaker's sides, particularly when compared to the midrange unit. In well-damped or very large rooms, this will make the speaker sound mellow, even taking the contribution of the rear-facing tweeter into account.

Fig.6 Genesis 500, lateral response family at 50", from back to front: responses 90 degrees-5 degrees off-axis, response on tweeter axis, responses 5 degrees-90 degrees off-axis.

Fig.7 Genesis 500, lateral response family at 50", normalized to response on tweeter axis, from back to front: differences in response 90 degrees-5 degrees off-axis, reference response, differences in response 5 degrees-90 degrees off-axis.

COMPANY INFO
Genesis Technologies
936 Chambers Court, Unit B3
P.O. Box 3789
Eagle, CO 81631
(970) 328-9515
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