Hi
what Dave writes sounds pretty logical if we presume that ~100% of the backwave energy is really coming through the horn-mouth, in this case Newton would really be laughing
My idea was that FLO13 might use some of the backwave energy that's otherwise lost (transformed into heat) in the compression chamber -- possible?
And if that is possible, does it and if yes how does it influence the backwave radiated through the horn mouth compared to a non BR loaded horn?
To be honest, I have to say I don't know, in both cases
I just don't have enough theoretical knowledge about BL-Horns to tell.
best
LC
what Dave writes sounds pretty logical if we presume that ~100% of the backwave energy is really coming through the horn-mouth, in this case Newton would really be laughing
My idea was that FLO13 might use some of the backwave energy that's otherwise lost (transformed into heat) in the compression chamber -- possible?
And if that is possible, does it and if yes how does it influence the backwave radiated through the horn mouth compared to a non BR loaded horn?
To be honest, I have to say I don't know, in both cases
I just don't have enough theoretical knowledge about BL-Horns to tell.
best
LC
Nothing ground breaking but here are pics of my latest BIB. Basically, they are the same as the 168S (older style with wizzer) but replaced with the cheaper Fostex 165k. Regardless of price I prefer the 165k and those will be the drivers that stay in my BIBs for a while. Both drivers are excellent.
http://www.zillaspeak.com/bib-godzillabib.asp
A few words about the 165k. This driver surprised me. It doesn’t look like much at all. But it’s richer and fuller sounding than the 168S. Comparing them side by side the 168S exhibits a phasey quality I never noticed before (wizzer?) and sounds thinner and dryer. The 165k is more fun to listen too and somehow rounder overall. It bops along in a more relaxed fashion and is very enjoyable. I’m glad I spent less and got more with this driver. Definitely worth a listen!
I will be away on business at a Microsoft convention most of next week. Everyone have a great week and enjoy the music!
Godzilla
http://www.zillaspeak.com/bib-godzillabib.asp
A few words about the 165k. This driver surprised me. It doesn’t look like much at all. But it’s richer and fuller sounding than the 168S. Comparing them side by side the 168S exhibits a phasey quality I never noticed before (wizzer?) and sounds thinner and dryer. The 165k is more fun to listen too and somehow rounder overall. It bops along in a more relaxed fashion and is very enjoyable. I’m glad I spent less and got more with this driver. Definitely worth a listen!
I will be away on business at a Microsoft convention most of next week. Everyone have a great week and enjoy the music!
Godzilla
I'm still having problems understanding this resonator bit. Example, if I take a 600 ml. plastic water or soft drink bottle and blow softly over the neck a note is produced. I know my lips produce an air vibration over the neck, presumably quite a complex vibration, but one note is produced and all other tones are suppressed. If I then fill the bottle one third full with water and blow over the neck with as far as I can tell the same sort of breath and therefore the same vibrations caused by the lip of the neck in the airstream, a higher tone is produced. The resonator is producing a higher output of one tone each time. If this is so could it not be of use to correct dips?
jamikl
jamikl
Greets!
Hmm, between the link I posted and Dave's explanation, I don't understand why you can't 'see the forest for the trees', but for sure a Helmholtz resonator can't fill a dip unless it's a minor one up in the vent's 1/2 WL pipe resonance, which is what you don't want it to do and one reason why it should be stuffed.
GM
Hmm, between the link I posted and Dave's explanation, I don't understand why you can't 'see the forest for the trees', but for sure a Helmholtz resonator can't fill a dip unless it's a minor one up in the vent's 1/2 WL pipe resonance, which is what you don't want it to do and one reason why it should be stuffed.
GM
peterbrorsson said:
Yep. That's why i qualified my comment. Without Ron's comment i would have called the elipse better with no qualifiers.
But Ron has software that literally allows him to see the wavefronts, so when he says something i pay attention.
Also keep in mind that any suprabaffle should have a trailing edge. The trailing edge makes a heavily champered circle into something closer to a sphere, which Olson's graph show as best.
If you have seen the iBIBj drawings it shows at least one layer of trailing edge -- more would be better.
dave
Going to step in hee and make some comments on what i have seen in my sims.
If you take a very large area flat baffle and IB loading you see the true FR curve.If you add a given shape baffle that has a given diffraction pattern the end result is a combination of the two.
A circular baffle will support a spherical wavefront an ellipse that is narrow will support a wavefront that takes on the shape of the baffle at a given frequency. As the frequency rises the support of the shape becomes less.
It all comes down to what wave length needs support and what shape you want the wave to be at a given frequency. Remember, at a given frequency the baffle is a secondary transducer with a wavefront that takes on the shape of the baffle. The edges of the baffle produce a later timed slightly attenuated wave. All in all its easier to design in a spherical baffle or a near pyramid shape because there is less edge diffraction than having to desing in the diffraction pattern to match the natural FR curve.
I believe that matching the two is what TC (RIP my friend) did on the Abby to produce the pleasing sound.
Audio is funny, so many opinions!
In my work i am not allowed to have opinions. Objective always wins over subjective.
ron
If you take a very large area flat baffle and IB loading you see the true FR curve.If you add a given shape baffle that has a given diffraction pattern the end result is a combination of the two.
A circular baffle will support a spherical wavefront an ellipse that is narrow will support a wavefront that takes on the shape of the baffle at a given frequency. As the frequency rises the support of the shape becomes less.
It all comes down to what wave length needs support and what shape you want the wave to be at a given frequency. Remember, at a given frequency the baffle is a secondary transducer with a wavefront that takes on the shape of the baffle. The edges of the baffle produce a later timed slightly attenuated wave. All in all its easier to design in a spherical baffle or a near pyramid shape because there is less edge diffraction than having to desing in the diffraction pattern to match the natural FR curve.
I believe that matching the two is what TC (RIP my friend) did on the Abby to produce the pleasing sound.
Audio is funny, so many opinions!
In my work i am not allowed to have opinions. Objective always wins over subjective.
ron
