Only the one 18" though?
The PA company I work for recently delivered one of these to the home of a private individual:
JBL :: Product
The PA company I work for recently delivered one of these to the home of a private individual:
JBL :: Product
I remember the first time i came across this:
Krell Industries, Incorporated, America's premiere manufacturer of high-end audio equipment: award-winning amplifiers, preamplifiers, CD players, DVD players, surround/sound processors, loudspeakers
kinda beastly, and it comes in black!
Krell Industries, Incorporated, America's premiere manufacturer of high-end audio equipment: award-winning amplifiers, preamplifiers, CD players, DVD players, surround/sound processors, loudspeakers
kinda beastly, and it comes in black!
Not sure about these specs
Checking out these specs, I see they give a max SPL of 121 dB and -1 db at 17 Hz. I presume that means a max SPL of 120 dB @ 17 Hz.
Since this is a sealed woofer, all of the spl has to come from the speaker cone-there is no vent to augment the bass output.
Following is the chart from Richard Small for the volume of air a cone in a sealed enclosure must move to achieve certain dB levels. The volume displaced equals the area of the cone, (Sd) times the excursion of the speaker, (from center to maximum outward point).
Here is the chart in square inches and in square centimeters:
Checking out these specs, I see they give a max SPL of 121 dB and -1 db at 17 Hz. I presume that means a max SPL of 120 dB @ 17 Hz.
Since this is a sealed woofer, all of the spl has to come from the speaker cone-there is no vent to augment the bass output.
Following is the chart from Richard Small for the volume of air a cone in a sealed enclosure must move to achieve certain dB levels. The volume displaced equals the area of the cone, (Sd) times the excursion of the speaker, (from center to maximum outward point).
Here is the chart in square inches and in square centimeters:
Attachments
Now to find the cubic inches necessary to produce 120 dB @17 Hz. The chart does not go that high at 17 Hz. But not to worry-we know that it takes four times the displacement volume to produce a frequency at the same volume level one octave lower. So we find the cubic inches required to make a frequency of 34 Hz @ 120 Hz and multiply that displacement by 4.
We see that 37 Hz takes about 128 cu inches displacement to produce 120 Hz, so 34 Hz probably requires about 140 cu inches. 140 cu inches times 4 equals 560 cu in, so to produce a 17 Hz sound at 120 dB requires about 560 cu inches for a sealed woofer to move.
To find the one way excursion, we divide 560 cu inches by the cone area of the 18 in woofer. We don't have the exact spec, but the Eminence Sigma 18 inch has a cone area of 176 sq inches and this 18 inch is likely to be similar.
560 cubic inches divided by a cone area of 176 sq inches equals a one way excursion of 3.18 inches.
I am not familiar with the voice coil or excursion with the woofer in this particular unit, but 3.18 inches for one way excursion is far more than any woofer I have come across, not that I have seen them all.
So I am somewhat suspicious of this unit's specs.
We see that 37 Hz takes about 128 cu inches displacement to produce 120 Hz, so 34 Hz probably requires about 140 cu inches. 140 cu inches times 4 equals 560 cu in, so to produce a 17 Hz sound at 120 dB requires about 560 cu inches for a sealed woofer to move.
To find the one way excursion, we divide 560 cu inches by the cone area of the 18 in woofer. We don't have the exact spec, but the Eminence Sigma 18 inch has a cone area of 176 sq inches and this 18 inch is likely to be similar.
560 cubic inches divided by a cone area of 176 sq inches equals a one way excursion of 3.18 inches.
I am not familiar with the voice coil or excursion with the woofer in this particular unit, but 3.18 inches for one way excursion is far more than any woofer I have come across, not that I have seen them all.
So I am somewhat suspicious of this unit's specs.
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They probably measured the in room response, with the sub corner loaded-an anechonic chamber may give a truer representation when comparing sub to sub-but who listens in one...
Nive looking piece of kit, but yes a TC sounds driver so you could build one yourself for less.
For real heavy weight systems Genesis Advanced Technologies High End Loudspeakers have the biggest I've seen-the sub tower housed 8x 12" and a full grown man could hang off the top-5.1 system weight was around 2.5tonnes IIRC
Nive looking piece of kit, but yes a TC sounds driver so you could build one yourself for less.
For real heavy weight systems Genesis Advanced Technologies High End Loudspeakers have the biggest I've seen-the sub tower housed 8x 12" and a full grown man could hang off the top-5.1 system weight was around 2.5tonnes IIRC
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