| Paul S wrote:|
|Scott, is it your specific aim to configure an enclosure to "effectively" lower driver Fs? While this, along with an exponential increase in power, is a proven strategy for generating ULF, it seems like this approach creates more of a sealed/"IB" hybrid that forfeits "true IB" "ease" for more (U)LF. This is not to say it certainly matters at ULF; just wondering.|
To be quite honest, as far as the Fs of the drivers used in the Infinite baffle, I felt they were already low enough, at 17 Hz.
Where I discovered the change in drivers specs was in the PUSH-PULL, slot load configuration, which is what I did for my mid-bass.
I used a pair (per side) of the Eminence Definimax 4012HO, and the fs dropped from 46 hz, down to 40hz, after measuring the pair, mounted in the plenum.
Power handling and use is not really much of a concern in either the IB bass, or the mid-bass. Both systems are extremely efficient. Having said that,
in both cases there is a tremendous amount of power reserves, as the amplifiers in each case are capable of providing just a tad bit less than the maximum power handling. But as an example of actual power usage, on really LOUD music, the mid bass averages 4 watts per channel, and the IB bass sometimes uses 1. As in 1 watt. I've never really taxed the system, but it will play back the Sheffield Track & Drum solo at live performance levels,
with an extreme amount of ease. In that case, the power levels do go up considerably, like 4 watts for the IB SUB and 16 watts mid-bass.
In the attached picture, please look close and you can see how the one driver in nestled just inside the other driver. This is a close up of the push-pull, slot load mid-bass.
And, just one last note for clarification; Infinite Baffle bass builds are to be done totally sealed.
The front and back waves of the driver(s) shall NEVER meet.