Is either of the most commonly used enclosure types like Bass reflex, MLTL or various types Transmission Line more excursion efficient than others.
By excursion efficient, I mean more port output against actual woofer cone movement.
Or does any of these type of enclosure has loading over a wider range of frequency?
I am planning for tuning frequency of around 32-38Hz for a two way using 7 inch driver. So, any band pass or tapped horn type enclosure with limited bandwidth won't likely work. I want a design that gives me the most SPL for whatever limited excursion I have from a 7 inch woofer.
I haven't decided on the woofer yet.
Thanks.
By excursion efficient, I mean more port output against actual woofer cone movement.
Or does any of these type of enclosure has loading over a wider range of frequency?
I am planning for tuning frequency of around 32-38Hz for a two way using 7 inch driver. So, any band pass or tapped horn type enclosure with limited bandwidth won't likely work. I want a design that gives me the most SPL for whatever limited excursion I have from a 7 inch woofer.
I haven't decided on the woofer yet.
Thanks.
From my experience, there is no audible differences in the excursion between MLTL and TL. TL's main advantage is it's lower terminus air velocity, and MLTL main advantage - it is more simple to build and will have a smaller volume for the same F3.
I think front loaded horn has them all beat...4th order bandpass. Maybe 6th order is louder? Additional resonance does not come without penalty.
The main factor in the size of the resonance you get from the enclosure is going to be size....whether BR/MLTL/TL etc....the larger the pipe, the larger the resonate note. The larger the enclosure, the more efficient it is at generating bass resonance is basically what you are looking at. 4th order tuning is better than BR in some respects but lowering tunings seem to result less differences between the two approaches. Larger vent CSA is more efficient at generating bass as well as total volume.
The main factor in the size of the resonance you get from the enclosure is going to be size....whether BR/MLTL/TL etc....the larger the pipe, the larger the resonate note. The larger the enclosure, the more efficient it is at generating bass resonance is basically what you are looking at. 4th order tuning is better than BR in some respects but lowering tunings seem to result less differences between the two approaches. Larger vent CSA is more efficient at generating bass as well as total volume.
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A backloaded horn can give more db down low and keep the high frequencies open, but ofthen have a phase issue between the front and the back of the driver that causes a coloured (distorted) signal. And it need a driver that is fit for it. And also, don't expect wonders from it, size of driver and xmax limit on how low and loud a driver can go. If xmax is limited and cone size also, it can still go low, but only on low volume.
You can model it in WinISD. Yes, a horn is the most efficient, but with it's own problems. For non-horns, the differences are all around Fb. Do some plots and it might scare you. Hint: I run a HP filter. Second hint: About 1/2 X-Max is where distortion skyrockets. Third hint: 32 Hz out of a 7 inch driver is asking to violate the laws of physics if you expect it to be loud enough to be useful. Even some of the super long excursion ( high distortion) drivers. You are not going to cheat Mother Nature.
I suggest if looking for efficiency, look to the driver selection.
IMHO, TL's were a hack before we understood the TS equations. Useless today. Good hack, but obsolete. 4th and 6th order are curious, but by definition bandpass, not highpass and usually describe impossible ports. Like a 2 foot box and a 20 foot port.
I suggest if looking for efficiency, look to the driver selection.
IMHO, TL's were a hack before we understood the TS equations. Useless today. Good hack, but obsolete. 4th and 6th order are curious, but by definition bandpass, not highpass and usually describe impossible ports. Like a 2 foot box and a 20 foot port.
Most excursion demanding frequency range in overall music is around 35Hz. But that logic a bass reflex tuned to 45 Hz is much worse than one tuned to 30Hz, unless you use a HF filter.
Speaking of HP filter, how do you do that in a passive crossover?
Agreed, say Fielder and Benjamin https://www.aes.org/e-lib/browse.cfm?elib=5147
Nevertheless I'd still tune low for reasons of
(a) less boominess
(b) less chance of really low notes below the port tuning frequency making the woofer go nuts
Not well. The impedances of the drivers really screw that up. Some people do it, with a lot of simulation time and big expensive parts.
The one redeeming thing about my Parasound amp is it has a 40 Hz 2nd order HP built in.