Is needed for a given degree of loudness. With human hearing, the lower you go, the more output The other issue arising with a lower and lower designed F3 May well end up bottoming, and in the worst case, destroy itself. In fact this additional mechanical travel is not available, then the speaker Octave extension requires 1/3 rd more peak excursion of the speaker. Sized box, but two very different tunings) that the lower 20 Hz tuning has aįar greater excursion requirement under real world conditions than the speaker white curve (which is the same speaker in the same Result, the peak excursion is higher for those systems where the box is tunedīy comparing the blue vs. Require greater excursions to be made before the port excursion relief is Is out of phase with the air coming from the woofer cone.) The general trend is that lower tunings (Below the port tuning, the port is no longerĪ resonator, it is simply a hole in the box, and the air coming out of the port The port frequency, the cone excursion increases rapidly. Tell from the curve above, the minimum excursion frequency of the system (belowĪbout 100 Hz) is the frequency where the box is tuned, so the port, not the Going to produce the same SPL with the same power applied. Remember, because of the efficiencyĭifferences between these woofers, the same power does not yield the same
Let’s take a look at the Cone DisplacementĬurve of all these woofers, in the same box, driven by the same power. The heavier woofers, this problem gets exacerbated by the need to move muchįarther when reproducing ever lower frequencies. Short, the gains below 30 Hz are paid for by the losses between 30 and 100 Hz.Īddition to the larger magnet we will need to control the higher moving mass of Without a speaker change, tuning the box lower simply The woofer shown in the white and blue curve is actually the same In short, if the 75 gram woofer has a 100 watt amp, we would need 800 wattsįor the 300 gram woofer to make similar SPL’s. Requires 9db more amplifier power relative to the lighter woofer from about 60 Hz So not only is the heavier woofer far more expensive to make, it Would have to have a much larger motor on it - (16 TM vs.
Bear in mind also that the 300 gram woofer The curves, these two systems are equally efficient at 42 Hz, the low note onĬlearly see from the 1 watt curve, there is a 9 db difference in efficiencyīetween the 75 gm and 300 gm woofer in favor of the lighter woofer. We have not only driven up the cost, we have also lost 4db of output at and Most importantly, in the search for more bass, Times the length of VC wire in meters in the magnetic field) has increased fromĪnd heavier, you need a bigger engine to move it about). Increase the magnet size substantially as the motor force (Gap flux in Tesla To double the mass of the woofer from 75 to 150 gms, and we have also had to Go down to the lower frequency without increasing the box volume, we have had But you do not have all the information yet. Here the woofer which can go lower seems to be the better of the two. Systems, I used Harris Technologies Bassbox Pro, version 6.Īt the following specifications and are asked to judge which system is better, The mass and stiffness of the speaker, size of the boxĪnd the diameter of the cone dictate how much efficiency you can get versus This is in short, the underlying basis for Loudspeaker system is actually like a high pass filter. System, but with a blank page to start with, what factors come into play that Yourself, “How low should it go?” how do we decide? We can use a computer program to model the You need to design a 12 inch woofer for a 2 cubic foot vented box that must
#Super pro bass box 2 12s driver#
Particular driver size and box enclosure. Real usable extension and efficiency for achieving the best performance given a Will explore the trade offs associated with tuning a vented subwoofer systemįor the lowest achievable frequency output and demonstrate a balance between Subwoofer can go in frequency before its sound output rolls off. Subwoofers performance by a simple metric its -3dB point or how low the Lately it’s quiteĪ popular trend on the AVS and Audioholics forums of people critiquing a Off the manufacturer may have committed to yield higher perceived power at theĮxpense of fidelity. Theater enthusiasts tend to get caught up in “how many watts” their amplifierĬan deliver without really understanding the meaning of the spec or the trade CarĮnthusiasts often judge a car solely by its 0 – 60 MPH acceleration time. Parameter in a products specifications to judge its true performance. More often than not consumers are swayed by a single