Backloaded horns, do we want delayed bass, and how do we want it?

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The CC distance of drivers has some "interesting" features. The physical distances are what they are, pretty simple. However as soon as driver has anyhing but ruler flat response the phase starts to shift, phasing is timing and timing is the same as "distansing". So due to this the acoustic center will shift especially near the high pass frequency of the driver or horn.
 
I know the time alignment will still be a problem if i just align voice coils. Will make a "rig" for the mid / tweeter to allow movement <-> to improve my luck getting it right. At least the woofer and mid will not be a foot+ off. Just trying to improve my chances to get some decent sound out of this speaker with the 1/3 driver backwards on the enclosure trick. This (horns) is new territory for me, see it as a beginners way of improving luck. Chosing easy to handle drivers, lots of extra bandwidth around the x-over frequencies hopefully will help me a bit to get it right.

Beautifull Sato :)
 
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I have used variovents in very small sattelites. First time i see it in a backchamber for a horn. For me it is new. Although not usable in a Back Loaded Horn.

A lot of the old German fullrange speakers have "socks" on the backside. Could be the same thing. Lol, i thought these where to keep the mice from eating the papercone.

Why not? BLHs have a filter chamber, no chamber is a pipe horn, though an offset driver one creates a crude filter chamber between the driver and horn throat. Critters go right through any mesh covers typically used to damp drivers by altering its Qms/Qts and one reason why the pioneers wound up using steel wool in their aperiodically loaded compression drivers.

GM
 
That's an interesting take, seeing the 1/3 length of the horn as a filter chamber or volume before the horn starts. Will try this in Aj-horn to see if computers says yes. I have only heard of steelwool in relation to closed box speakers. Strange story about temperature is what i remember from it. Will google the steel wool in compression drivers. Interesting.
 
It's a complex resonator in that there's the whole horn's 1/4 WL fundamental and 1/2 WL horn pipe harmonics as well as the open horn pipe fundamental/resonances of the throat/woofer 'stub'. Ditto when there’s a vent.

Don't know of any docs WRT the steel wool tweak unless it's in the patent, so curious what you may find, I learned it from an EE that had apprenticed at Bell Labs/W.E. during the early days of its cinema sound installs development.

GM
 

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The Oberton 8M250 simulated with the 1/3 of the line as backchamber volume. Linelength 1.54 meter instead of 2.30. Troath 112 cm2 instead of 74 cm2. Aj-Horn thinks 1/3 placement driver, is sort of an horn. Blackline is with the 1/3 as volume.

An externally hosted image should be here but it was not working when we last tested it.


Otoh it maybe a giant mousetrap.
 
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