Any effect of those unshielded drivers on your screen? Also, that looks like a pretty short horn so it's surprising the bass you seem to be hearing. It would be interesting to see measurements since what you think of as low bass may or may not be the same as I or others.
Anyway, good work. I'm hoping to play with a TL/MLTL or some such with some Fountek FE85's I have (3" so I'm not expecting much from them).
I tried multiple variations, and I only ever ended up with one file. This was on my iPad. I think I've done it before from my computer. Just a minor annoyance.
Look at the big speakers that are on the outside, these go down to <30hz. While what I hear is not nearly that low, I do know what bass will sound like. These little things are pretty satisfying.
I didn't see any impact on the screen.
I still don't know what the internal folds and geometry looks like but can imagine it sounds like a rear firing BLH. Funny how my first micro BLH was also made using a USPS box and tape. The path will probably be too short to have any bass lower than 100Hz is my guess.
The browser in iOS on iPad and iPhone only supports one pic at a time.
The browser in iOS on iPad and iPhone only supports one pic at a time.
That's what I thought too, but it does seem lower.
Well, before I sent the above message I plugged my iPad in and checked by ear, and it went down to 72 before it started falling off. And while I won't swear to it, it sounded pretty flat down from the 125hz preset I used to start.
Just imagine my box, closed on all sides. 12x12x6 internally. Now take the rear panel, and swing it in from the top, and fold the last quarter of it straight up in the center. That's exactly what I did on the cardboard box. If you swing it in at 45° the length would be 1.414*6 when it crossed the center based on good ol' Pythagorous. The angle I used was slightly greater than 45, so maybe more like 1.5*6 or 9", with 3" pointing up.
Like I said, if I knew what I was doing, it would never work.
Well, before I sent the above message I plugged my iPad in and checked by ear, and it went down to 72 before it started falling off. And while I won't swear to it, it sounded pretty flat down from the 125hz preset I used to start.
Just imagine my box, closed on all sides. 12x12x6 internally. Now take the rear panel, and swing it in from the top, and fold the last quarter of it straight up in the center. That's exactly what I did on the cardboard box. If you swing it in at 45° the length would be 1.414*6 when it crossed the center based on good ol' Pythagorous. The angle I used was slightly greater than 45, so maybe more like 1.5*6 or 9", with 3" pointing up.
Like I said, if I knew what I was doing, it would never work.
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Maybe you can draw a sketch. Still don't get it. You have the rear panel folded in to form the mouth and just the one 25% section folded in again? That would give you a large rear chamber, a small constriction vent leading to the expansion mouth. It is sounding more like a BVR (big vent reflex than a BLH) which may explain why you are getting sub 100Hz output. Again a sketch would help. In the future don't forget to take photos of the build before buttoning it all up.
If the back is open, then sort of. It is much narrower, and then square sides. Also, the diagonal internal baffle, where it bends slightly in the diagram, is bent straight up in mine. And no stuffing at all, although I was going to play with that at some point.
My daughter is probably going to take them from me, so I'll be finishing up the second one in foamcore in the next few days and I'll take an open side pic. I may have to buy a second set of FE126's, but I guess the newer EN version.
My daughter is probably going to take them from me, so I'll be finishing up the second one in foamcore in the next few days and I'll take an open side pic. I may have to buy a second set of FE126's, but I guess the newer EN version.
Some neat stuff here by kenpeter. http://www.diyaudio.com/forums/subwoofers/258433-light-air-slot-loaded-band-pass-sub-8.html#post4084491
So after listening to these all evening, into the wee hours, I found that having both drivers in the same design box sounds even better.
One thing though, and this doesn't really have anything to do with the box, is that these are my first high efficiency speakers. As such, I'm hearing all the noise that my system puts out. My 6B4G push-pull amp hums like crazy, I have at least one noisy tube, and when I hooked the speakers to a class D amp, I heard all kinds of buzzes being picked up by the input cable, power supply, and the amp itself. When I switch in phono I get even more hum. With my 83db (if that) speakers I didn't hear it at all from my listening position, and would only hear the hum up close.
One thing though, and this doesn't really have anything to do with the box, is that these are my first high efficiency speakers. As such, I'm hearing all the noise that my system puts out. My 6B4G push-pull amp hums like crazy, I have at least one noisy tube, and when I hooked the speakers to a class D amp, I heard all kinds of buzzes being picked up by the input cable, power supply, and the amp itself. When I switch in phono I get even more hum. With my 83db (if that) speakers I didn't hear it at all from my listening position, and would only hear the hum up close.
Even with 95dB sensitive drivers, you should not have all that hum and noise in a good class D amp with appropriately shielded input wires and filtering on the output. I have 108dB sensitive drivers when in a tractrix horn and my TPA3116D2 does not have hum or noise issues. Make sure you don't have ground loops and use shielded RCA cables between the source and amp. Tie things to earth ground if possible. What class D amp are you using.
Now that I see the inside of your speaker box, it is not a horn - maybe a very short TL. The longest path is less than 18in x 2 due to the expanding mouth. I am guessing it probably has an fb of 125Hz at best. It is probably close to a semi open baffle. You can get a lot more deeper bass if you made a longer maze like TL that slowly contracts.
Now that I see the inside of your speaker box, it is not a horn - maybe a very short TL. The longest path is less than 18in x 2 due to the expanding mouth. I am guessing it probably has an fb of 125Hz at best. It is probably close to a semi open baffle. You can get a lot more deeper bass if you made a longer maze like TL that slowly contracts.
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It is a type of acoustic lens for a compression driver made by stacking plates.
https://m.youtube.com/watch?v=RU4n48kTqSk
https://m.youtube.com/watch?v=RU4n48kTqSk