Where did you get 9.5 from?
First lets sort out the mystery of Altec horn loading midbass with measurements;
828G loads around 180hz
816A about 180hz as well
dual 515's in 817 loads around 120-140hz
dual 515's in 210a again loads around 180hz
View attachment 64061
These are roughly where there is actually horn loading. Altecs use horn, direct radiator and bass reflex all at the same time in some of them.
Also, please also note not all horn loading is the same. As you can see from the examples some short horns are seemingly loading as low as my large horn. Please check the efficiency gain. Having those large throats does not let you load like you would like. Although I have an 12" driver, I do not have 12" throat.
Yes, it does but there is no horn gain there.So figure 3 is showing 100 db at 100 Hz?
Yes, it does but there is no horn gain there.
Where is the horn gain stopping
From figure 3, what I am seeing is, the top line (horn cabinet) is averaging around 105 db and going down to 100 db at 100Hz, and flatlining at 100 db till 60ish Hz, after which it drops off (must be the Fc of the horn).
You can never turn the vents off, shown on the bottom line, and they must be contributing, but they take over alone (no horn) towards the bottom and are giving 90db at 20Hz, as per the graph.
You've probably seen this, but was looking at subs and saw that Funk Audio custom makes these dual 15" FLHs and thought you might be interested...From figure 3, what I am seeing is, the top line (horn cabinet) is averaging around 105 db and going down to 100 db at 100Hz, and flatlining at 100 db till 60ish Hz, after which it drops off (must be the Fc of the horn).
You can never turn the vents off, shown on the bottom line, and they must be contributing, but they take over alone (no horn) towards the bottom and are giving 90db at 20Hz, as per the graph.
You've probably seen this, but was looking at subs and saw that Funk Audio custom makes these dual 15" FLHs and thought you might be interested...
https://www.funkaudio.ca/store/p46/15.H_Horn_subwoofer_Custom_order.html
Got it. Would you also consider dual FLH for low bass?Thanks. Just to clarify the 15 inch dual woofer front loaded horns I was writing about are for Midbass. These are for the next level down. this is one 15 for the lower bass. Leif has made himself one 21 inch. There are other solutions as well including the open baffle type multiwoofer with a slit in the middle of the plane that Western electric had demoed at Munich last year. But all those require space.
Got it. Would you also consider dual FLH for low bass?
Thanks. Good to know.It is not as important to me. I don't think I am adamant on a type of solution there. It should roll over properly from the Midbass horn, and give sufficient weight, ambience, detail. I have heard good Midbass with a big front loaded horn, sealed subs, and there are also cheap horn loaded DIY alternatives the size of a small fridge to be kept in the corner. All could work.
Thanks. Good to know.
Will bear that in mind.The main thing for me is the dual woofer FLH for the Midbass. That is what integrates the speaker and is the Achilles heel of most, in fact nearly all speakers. The upper mids, highs, and lower bass can be managed to preferences. Want density and roll off? Easy. Want clean extended highs? Equally easy. And so on.
The main thing for me is the dual woofer FLH for the Midbass. That is what integrates the speaker and is the Achilles heel of most, in fact nearly all speakers. The upper mids, highs, and lower bass can be managed to preferences. Want density and roll off? Easy. Want clean extended highs? Equally easy. And so on.