Systems List › DIY › GJALLARHORN
The response matches the simulated data well. There is slightly less sensitivity than the model, but it is still good. The driver unloads below 16Hz quickly so a high pass filter at about 15Hz is required. A 24dB octave Butterworth filter is recommended. The subwoofer offers very high output both long term and short term. From 16-63Hz, which is a very rich content zone for theater type bass, the output is especially impressive with a 2 meter rms GP CEA2010 passing output of 118.3dB recorded at 16Hz and 122db at 20Hz. Translating to 1 meter peak output numbers results in output levels of 130-140dB from a single cabinet over the entire 20-100Hz range and greater than 127dB at 16Hz.
Looking at the distortion results the THD is very low up until the highest output levels and between 15-50Hz is incredibly low at staggering output levels. The combination of output headroom plus the very low distortion between 15-50Hz is something that is special and audibly impressive with large bass transients that fall in this range. Four of these cabinets should be able to provide reference level theater LFE channel reproduction, including redirected bass, from 15-100Hz, outdoors at a listening distance of 10 meters.
This system must have EQ to help tame the resonances inherent in the tapped horn loading of the cabinet at 63Hz and the 95Hz range plus a 15Hz high pass filter as the driver unloads below there. This system would operate best limited to 70 or 80Hz and lower as it exhibits higher distortion levels, jagged response and ringing in the time domain higher up in frequency due to the loading of the tapped horn design utilized here.
There is a very large amount of compression shown in the top 3 sweep levels at certain frequencies. This behavior is interesting in part because there is correlation with the peaks in the tapped horns response and maximum areas of efficiency. This behavior was also noted in the tests of the DTS-10 and DTS-10 with the LMSR drivers. It appears to be some sort of output "wall" is reached where further power increases result in little or no further output. We suspect this limit occurs from either drag and or turbulence in the horn path which causes losses in loading and efficiency.