Never did go into the particulars here Neo; why did you build this; "if you build it, he will come"?
It must have been hard to build and to move around.
It must have been hard to build and to move around.
Interesting...
I built this for a friend almost 15 years ago IIRC. He had been into audio practically all of his life and were discussing stuff he previously had which included massive bass arrays. And so I ran some numbers and came up with something "new". IIRC it is 8-4'x8' sheets and is ~350#. The sides and baffle are 2.25" and the rest is 1.5", the port opening is 20.5"x5". So sure - getting this thing moved into a house is a chore. Even though it is HEAVY I can move it around on carpet by myself, and without the drivers in it I can also stand it up by myself. I'm not in the greatest shape either. Anyway this became mine a couple years back and it's at another friends place, but they are afraid to use it because they might break the house or something. It's OK for the home theater bass but the stuff I do now is WAY more fun even though it lacks in the lowest couple octaves.
One of my other friends had it for a bit. He wanted to mount a stripper pole to it, but this guy also built a half pipe in the house between the living room and kitchen so this is no biggie really...
One of my other friends had it for a bit. He wanted to mount a stripper pole to it, but this guy also built a half pipe in the house between the living room and kitchen so this is no biggie really...
Actually not, as my computer is also linked to the TV, so I get both screens showing!
But does that account for room boost, and transient response? As I said, I have done it this way before, and like the sound.
And no, I don't want to buy new drivers; I'm poor, remember? Besides, the wood is cut!
@ Etocynned
Here is a small scale example how to tune a box with semi built box and clamps.
These are flare ports to give this box a bit of low end; I guess I could have thought this with out calculator (hours), but instead trimmed the wood flares as needed to reach the 60HZ tuning.
The box does go down to 50hz which is very good for this FR driver.
Here is a small scale example how to tune a box with semi built box and clamps.
These are flare ports to give this box a bit of low end; I guess I could have thought this with out calculator (hours), but instead trimmed the wood flares as needed to reach the 60HZ tuning.
The box does go down to 50hz which is very good for this FR driver.
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Huh? No it's Richard; have I missed something here? I usually do!Is your name Doug?
double trouble
awkward....I think the train has left the station; the pieces are cut yes? you have this idea about a sealed box yes?
One fellow did post something about Iso sealed boxes (I'll try to get this right). Since the one woofer is compressing the air inside the box and the opposite woofer is "floating" outside - they get out of sync (air builds up between the cones). This is more of a problem the louder you play it and less of a problem with a ported box.
btw, they do manufacture mechanical coupled Iso drivers.
Onward!...post pics when done, looking forward to your results.
awkward....I think the train has left the station; the pieces are cut yes? you have this idea about a sealed box yes?
One fellow did post something about Iso sealed boxes (I'll try to get this right). Since the one woofer is compressing the air inside the box and the opposite woofer is "floating" outside - they get out of sync (air builds up between the cones). This is more of a problem the louder you play it and less of a problem with a ported box.
btw, they do manufacture mechanical coupled Iso drivers.
Onward!...post pics when done, looking forward to your results.
You have it backwards... isobaric works better in a sealed box than a ported box. The "outer" driver of an air-coupled isobaric pair is always going to move further than the "inner" driver. The difference in excursion is proportional to the difference between the volume between the drivers and the volume of the box. With a ported box, the box gets very "stiff" (acts like a very small box) at port resonance.
The main idea is correct; I'd be okay with 1/2 credit.
e.g. I had a good size, Iso, 2 pair, 10" "floppy" cone woofers box. The weirdness was one pair did fine, the second pair simply did not work. If it was turned up, one driver was pegged into the basket (room side). I did see others have had this issue.
I did try resealing it, didn't change a thing. My guess here is that a speaker with a tighter suspension would be a better choice. (it might self correct)
OR a smaller cone, as far as I know, never had a problem with the 8" mcm woofers.*
Something to think about, would a small 1/16" vent hole, be better or worse?
* my buddy never sent the response curve, however in the the spirt of diy gave me a calibrated microphone and said "DIY my friend"....Need to look and download RTA?
e.g. I had a good size, Iso, 2 pair, 10" "floppy" cone woofers box. The weirdness was one pair did fine, the second pair simply did not work. If it was turned up, one driver was pegged into the basket (room side). I did see others have had this issue.
I did try resealing it, didn't change a thing. My guess here is that a speaker with a tighter suspension would be a better choice. (it might self correct)
OR a smaller cone, as far as I know, never had a problem with the 8" mcm woofers.*
Something to think about, would a small 1/16" vent hole, be better or worse?
* my buddy never sent the response curve, however in the the spirt of diy gave me a calibrated microphone and said "DIY my friend"....Need to look and download RTA?
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299-114 vs 29-305
Dan,
Thanks again for showing me the light (how to clip pics and edit).
Check this out...Could this be the 8ohm version of the 4 ohm 299-114
Dayton classic 29-305 (too bad they cost $20 and not $8)
Dan,
Thanks again for showing me the light (how to clip pics and edit).
Check this out...Could this be the 8ohm version of the 4 ohm 299-114
Dayton classic 29-305 (too bad they cost $20 and not $8)
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