Hello,
I am currently in the process of putting together a proposal for the purchase of some new subwoofers for the University I work for. Currently, we have been using 4 EV Mtl-4's and I would like to replace them with Danley TH118's. However, when I went to compare the sensitivities between the two cabinets I was surprised at how the Mtl-4's stood up.
Brandon,
Sensitivity aside, one must look at low frequency response and ultimate output.
The DL18W woofers used in the MTL-4 have an Xmax of 5.6 mm.
The DSL TH-118 (depending on vintage) uses either an 18 sound or the current B&C18SW115-4, both drivers have about 15mm Xmax, just under the displacement capability of only three of four DL18W.
The lighter weight DL18W are more sensitive than a 18SW115.
Tapped horns can raise the sensitivity of a speaker by around 6 dB over a bass reflex (BR) cabinet, and slightly more than a bandpass box (BP).
The MTL-4 falls somewhere along the continuum of BR/BP, and has a higher low frequency corner (around 45 Hz compared to around 35 Hz) so would likely have more potential output (and sensitivity) above 45 Hz than a single TH-118, while the TH-118 would have more output below 45 Hz.
Although the MTL-4 and the TH-118 try to cheat Hoffman’s Iron Law, it applies to tapped horns as well as bass reflex cabinets, the lower the frequency response, the less output capability.
I’d say your estimate chart looks pretty reasonable, probably giving the TH-118 a bit more than it is due.
DSL does do demos, a side by side test is the only way to really tell for sure which cabinet has more output at the frequencies of interest.
Art Welter