ROAR with Helmholtz front resonator

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If you trade the high efficiency of the ROAR for an extended bandwidth, but you stick with the QW based series 8th order BP, you end up with a strange looking simulated beast. It does need lots of DSP and some careful use of damping to tame the response to something suitable for indoor use.

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Im interested in a bandwidth like this for near field subs. I want the non linear attack for movies. Would this be a large enclosure? Maybe with a 12 or 15?
 
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interesting, the added length/resonator sure seems to suck out the middle of the bandwidth ?
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TP12LL34

I built a 12 inch version of this in the thread above.
There is measurements and a lot of discussions of the pros and cons of this kind of design.

But massive amounts of positive acoustic feedback does sound "odd" to some people.
im having trouble modeling the hroar. i prefer hroar's form factor over the tp12ll34 or roar. i have dayton 12lf at my disposal currently. when i try to model it for hroar it just becomes a bunch of spikes and no useable bandwidth. ive tried the bp6s and th w/ chamber methods but cant seem to work it out.
 
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i have dayton 12lf at my disposal currently. when i try to model it for hroar it just becomes a bunch of spikes and no useable bandwidth. ive tried the bp6s and th w/ chamber methods but cant seem to work it out.
It's because with a 0.21 Qts it's a compression horn or high power midbass prosound driver that in theory 'wants' a vented 20*1247.8*0.21^303 = 17.15 L, 0.42*28*0.21^-0.96 = 52.6 Hz Fb.
 
interesting, the added length/resonator sure seems to suck out the middle of the bandwidth ?
Since you add mass (long L34 acts as a passive radiator) and with the help of the massive positive acoustic feedback enhance the upper part of the passband, you effectivly strech out the usable passband. The dip in the response is an area where the driver gets somewhat unloaded from the resonators and I would guess that the acoustic feedback (resonator feeds back through the driver) gets out of phase enough to become negative feedback.
 
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If you balance a ROAR with an added quarter wave front section between the driver and the front resonator then you can get a very wide usable bandwidth. I have no idea how it will sound in real life, but it does look nice in Hornresp.
It is basically an 8th order ROAR15.
What would this look like as a schematic? I don't see where you would add another resonator between the two... 3 resonators, I think this box would be cumbersome. Also, Why are you modeling these as helmholtz bp and not th?
 
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you will be stuck listening to this as motor/mechanical noises or spiders at xmax etc...... its weird!!

I think there’s more to it than that as well? Harmonic distortion from lower notes being played but exciting those other resonances?.? Things I don’t understand but can ‘hear’?
 
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