Hi Soldermizer,
Post #19: "...has ANYONE really read the entire "collaborative tapped horn" one?"
The tapped horn and especically the original collaborative thread were my main reason to even look at diyaudio. I have read through most - if not all - pages of that thread, and I don't feel alone.
You might take another look at Post #18, there you have a combination T-TQWT / TH that can actually be implemented.
Any, have fun.
Regards,
Post #19: "...has ANYONE really read the entire "collaborative tapped horn" one?"
The tapped horn and especically the original collaborative thread were my main reason to even look at diyaudio. I have read through most - if not all - pages of that thread, and I don't feel alone.
You might take another look at Post #18, there you have a combination T-TQWT / TH that can actually be implemented.
Any, have fun.
Regards,
Hi Soldermizer,
Just some more quick notes/comments/link: You have probably already looked at the DTS-10 thread here:
Danley DTS-10 "Super Spud" DIY kit
That's how one of these high-powered horns should be build.
Use a void-free plywood (should be about half the price of solid core doors or less) or MDF, route shallow (~ 1/8-1/4") channels for the dividers, provide access panels (w/ hurricane nuts / T-nuts) for the drivers and for damping material. Note the details about the driver mounting boards, and the supports (bracing) in that area. (Take a look at the drawing in your thread, Post #18, does the driver mounting and the fold look familiar now?)
Using 4'x8' sheets will give you more freedom with your overall size, and you might well end up w/ a higher quality product.
Also, use a PL Premium construction adhesive and screws. You need to avoid leaks, or you will not know what you have built.
Regards,
Just some more quick notes/comments/link: You have probably already looked at the DTS-10 thread here:
Danley DTS-10 "Super Spud" DIY kit
That's how one of these high-powered horns should be build.
Use a void-free plywood (should be about half the price of solid core doors or less) or MDF, route shallow (~ 1/8-1/4") channels for the dividers, provide access panels (w/ hurricane nuts / T-nuts) for the drivers and for damping material. Note the details about the driver mounting boards, and the supports (bracing) in that area. (Take a look at the drawing in your thread, Post #18, does the driver mounting and the fold look familiar now?)
Using 4'x8' sheets will give you more freedom with your overall size, and you might well end up w/ a higher quality product.
Also, use a PL Premium construction adhesive and screws. You need to avoid leaks, or you will not know what you have built.
Regards,
Oh pul-leeze, why would I consider a design from a man just because he has decades of patents to his name? 
On a more serious note, I may just have to buy a router (the "not-Linksys" type)...
Soldermizer, still looking for a loophole, convinced there must be such as thing as void-free hollow core slab doors
On a more serious note, I may just have to buy a router (the "not-Linksys" type)...
Soldermizer, still looking for a loophole, convinced there must be such as thing as void-free hollow core slab doors
Like I said, commercial NFPA fire rated doors, which AFAIK are required in all commercial buildings. My workshop tabletop is made from two closet doors that were going to be scrapped when someone changed an office plan. It pays to have an architect buddy when you're a DIYer. 1.75" thick and mostly wore out a cheap new carbide tipped blade shortening them. Flush Solid Core Hardboard (HDF) Fire Rated 20 Min Door FLUSHFR20 | Fire Rated Doors
GM
GM
Driver mounting options
Not sure I am up to anything as complex or involved as a Danley clone but I will will read it to see how quality work is done. I am still modeling simpler (one fold) TH and kin to see what gets decent response.
I am moving forward enough that I want to get the Brain Trust to comment on driver mounting. I am committed to using two of my Alpine 15" (currently in the Frankenclosure). Of the several mounting options, I believe that the push-push (force canceling) is the most valid design goal, especially considering my propensity for "alternative" methods and materials.
Push-push can be done (of course) with cones in, cones out, or the alleged distortion reduction of using push-pull but inverted phase. I have not committed to any but want to run this by youse guys:
Here is a thread about this from 2007:
http://www.diyaudio.com/forums/subwoofers/107910-push-push-subwoofer-spacing.html
I plan to have a "double horn" (or a pair of mirror images, whatever you'd like to call it.) This still leaves the three options mentioned above. But her is my scheme which would involve the irreversible step of
1. cement the magnets of the two drivers to each other. I have seen this for some FR designs but not for subwoofers. Why not? Obviously this will preforce limit me to a determined S2 (or S3) but I can sim for that value. Also, I realize that my path will probably not be able to taper much if at all (if using a single board per speaker).
2. Using this scheme (or the two "rears" of the speaker near the mouth unglued) also allows the very easy hook-up option of easy access to the speaker terminals, of which each Alpine has many (dual voice coil). This would allow maximum flexiblity for hooking them up, including driving from two channels of an amp, hooking them up incorrectly and canceling all the low frequencies, and other options I've yet to try. And even hooking them up so they work optimally
The main downsides I see are:
1. Will not have the alleged distortion cancelation if used push-pull inverted.
2. More prone to mechanical noise being near the port.
I have "spec-ed" 3/4 " pressure-treated plywood for the interior panels. It was reasonably priced, very heavy and Lowe's cut it for me
I envision building a sort of frame for the speaker pair, whether glued or braced more conventionally. This framework will "float" in the bigger enclosure at least at first, allowing for fine-tuning of the "design" such as it is.
This is unacceptable for the innards of my subwoofer:
Not sure I am up to anything as complex or involved as a Danley clone but I will will read it to see how quality work is done. I am still modeling simpler (one fold) TH and kin to see what gets decent response.
I am moving forward enough that I want to get the Brain Trust to comment on driver mounting. I am committed to using two of my Alpine 15" (currently in the Frankenclosure). Of the several mounting options, I believe that the push-push (force canceling) is the most valid design goal, especially considering my propensity for "alternative" methods and materials.
Push-push can be done (of course) with cones in, cones out, or the alleged distortion reduction of using push-pull but inverted phase. I have not committed to any but want to run this by youse guys:
Here is a thread about this from 2007:
http://www.diyaudio.com/forums/subwoofers/107910-push-push-subwoofer-spacing.html
I plan to have a "double horn" (or a pair of mirror images, whatever you'd like to call it.) This still leaves the three options mentioned above. But her is my scheme which would involve the irreversible step of
1. cement the magnets of the two drivers to each other. I have seen this for some FR designs but not for subwoofers. Why not? Obviously this will preforce limit me to a determined S2 (or S3) but I can sim for that value. Also, I realize that my path will probably not be able to taper much if at all (if using a single board per speaker).
2. Using this scheme (or the two "rears" of the speaker near the mouth unglued) also allows the very easy hook-up option of easy access to the speaker terminals, of which each Alpine has many (dual voice coil). This would allow maximum flexiblity for hooking them up, including driving from two channels of an amp, hooking them up incorrectly and canceling all the low frequencies, and other options I've yet to try. And even hooking them up so they work optimally
The main downsides I see are:
1. Will not have the alleged distortion cancelation if used push-pull inverted.
2. More prone to mechanical noise being near the port.
I have "spec-ed" 3/4 " pressure-treated plywood for the interior panels. It was reasonably priced, very heavy and Lowe's cut it for me
I envision building a sort of frame for the speaker pair, whether glued or braced more conventionally. This framework will "float" in the bigger enclosure at least at first, allowing for fine-tuning of the "design" such as it is.
This is unacceptable for the innards of my subwoofer:
Attachments
Last edited:
Making progress -- slowly -- in cannibilizing the old Frankenclosure. After much fruitless activity with screwdriver and pliers I said something that rhymes with 'bucket' and got out the drill and drilled out the remaining bolts. Easier. Minimal to no iron filings in speaker motors. Great! I have most of the wood I need for the new box and a plan (sort of).
I need to put the 15-inch mounting holes in the two baffles. The 15-inch hole is a special size and is back ordered at Home Depot
I need to put the 15-inch mounting holes in the two baffles. The 15-inch hole is a special size and is back ordered at Home Depot
More photos!
A rare glipse of the Lair of the Soldermizer. I finally got off my lazy , um, sofa and cut the holes for the drivers. Here is a photo of my "work shop". Note strategic use of furniture to save money on buying sawhorses.
Next: how to glue these cellulose rectangles without buying clamps (buy clamps, perhaps?). Also beg the neighbor to help me move it into the living room.
A rare glipse of the Lair of the Soldermizer. I finally got off my lazy , um, sofa and cut the holes for the drivers. Here is a photo of my "work shop". Note strategic use of furniture to save money on buying sawhorses.
Next: how to glue these cellulose rectangles without buying clamps (buy clamps, perhaps?). Also beg the neighbor to help me move it into the living room.
Attachments
Look at the backside, there's a vent hole, so the drivers need to be either spaced apart 'X' distance from each other or 'Y' distance from a parallel wall. Find out from Alpine what 'X', 'Y' is to determine the minimum distance between driver/baffle or dual drivers/baffles.
GM
Hi GM! Actually I have decided to go with a more conventional (not glue together the magnets) in other words -- dual-opposed push-pull (I should know what these are called by now! We need some government regulation in our hobby [grin] ) ... the best of both worlds, the cancellation of forces (even I can understand that one!) as well as the more dubious "cancels second harmonics" benefit.
In the meantime...who would have thought a hacksaw would be useful in building a sub? (Recommended by sales droid at Lowe's for cutting PVC pipe -- which will be (I hope!) a satisfactory bracing for some panels. Film at 11.
In the meantime...who would have thought a hacksaw would be useful in building a sub? (Recommended by sales droid at Lowe's for cutting PVC pipe -- which will be (I hope!) a satisfactory bracing for some panels. Film at 11.
Nearing the end...
I finally have sealed the last piece (top) on the current box. How well it will work remains to be seen. I am not highly optimistic
I will give you a better report when some testing is done.
Meanwhile, I have ascertained that my big subwoofer box is too big to move out of the room in which I assembled it. On the upside, it is right next to my listening room so with sufficient amplification should work ok.
If I remove one of the windows it would probably fit through the opening thus made. It's reassuring to know I can have it moved into the living room at some point, otherwise it will "convey" when the house is sold
I finally have sealed the last piece (top) on the current box. How well it will work remains to be seen. I am not highly optimistic
I will give you a better report when some testing is done.
Meanwhile, I have ascertained that my big subwoofer box is too big to move out of the room in which I assembled it. On the upside, it is right next to my listening room so with sufficient amplification should work ok.
If I remove one of the windows it would probably fit through the opening thus made. It's reassuring to know I can have it moved into the living room at some point, otherwise it will "convey" when the house is sold
Pondering...
I am still listening, testing, and tracking down the renegade buzzes that are the result of (dare I admit it?) building an enclosure out of 4 -- hollow -- door slabs. I was warned against but cheapness got the better of me
Rather than, uh, comment on their sound yet, I found a golden quote from Mr. Van Alstine ("Audio Basics", Mar. 1990 issue): Regarding a different woofer (not mine) he had this to say: "If the bass does not sound like herd of whales farting, then [the average consumer thinks that] it cannot be any good." I don't know about the cetacean flatulence, but many people here would say my current build is lower than whale s---t
I am still listening, testing, and tracking down the renegade buzzes that are the result of (dare I admit it?) building an enclosure out of 4 -- hollow -- door slabs. I was warned against but cheapness got the better of me
Rather than, uh, comment on their sound yet, I found a golden quote from Mr. Van Alstine ("Audio Basics", Mar. 1990 issue): Regarding a different woofer (not mine) he had this to say: "If the bass does not sound like herd of whales farting, then [the average consumer thinks that] it cannot be any good." I don't know about the cetacean flatulence, but many people here would say my current build is lower than whale s---t
It's done...
Here is a post-mortem of the Ijit Mark II. Based on results, I'm going to name it "Frankenclosure II" instead. That's not completely fair, as this affront to the hobby of speaker-building actually had some modelling and planning. I will post the Hornresp and dimensions should anyone care (maybe already did?).
Bragging (?) rights: This project is built completely without any fasteners. I did use some nails to temporarily tack stuff. It is built from nearly all off-the-shelf parts. The only cutting done was at Lowe's for the two interior baffles and by my own self for the two circle holes for the drivers.
Parts list (more or less):
2x slab door, hollow, 24" wide. by ? 80" high (standard height).
2x slab door, hollow, 36" wide.
1x 4x8' sheet of 3/4 ply
Bottle(s) of Gorilla Glue
Silicone caulk for sealing
2x gallons of rubberized driveway sealer for desperate final sealing
Finish was a witches brew of clear polyurethane varnish, blue oil-based paint, and white latex. It produces the "interesting" finish you see here (and on my walls and floor and me...)
As noted before, it is too big to move out of the room in which I assembled it. Fortunately it is right next to my listening position. How does it sound? Not perfect but does provide some bass which was the original goal anyway
Curious: I got more stuff rattling with my older attempts, including the easy of easies, the Sonotube TL that got me started on this accursed hobby
Next time I should just buy a Danley perhaps.
For all those here who tried to help me, a word of thanks. My gift to you is this: I have temporarily satisfied my inner mad scientist (or become too embarrassed?) and will not likely undertake any new projects until I've recovered.
Here is a post-mortem of the Ijit Mark II. Based on results, I'm going to name it "Frankenclosure II" instead. That's not completely fair, as this affront to the hobby of speaker-building actually had some modelling and planning. I will post the Hornresp and dimensions should anyone care (maybe already did?).
Bragging (?) rights: This project is built completely without any fasteners. I did use some nails to temporarily tack stuff. It is built from nearly all off-the-shelf parts. The only cutting done was at Lowe's for the two interior baffles and by my own self for the two circle holes for the drivers.
Parts list (more or less):
2x slab door, hollow, 24" wide. by ? 80" high (standard height).
2x slab door, hollow, 36" wide.
1x 4x8' sheet of 3/4 ply
Bottle(s) of Gorilla Glue
Silicone caulk for sealing
2x gallons of rubberized driveway sealer for desperate final sealing
Finish was a witches brew of clear polyurethane varnish, blue oil-based paint, and white latex. It produces the "interesting" finish you see here (and on my walls and floor and me...)
As noted before, it is too big to move out of the room in which I assembled it. Fortunately it is right next to my listening position. How does it sound? Not perfect but does provide some bass which was the original goal anyway
Curious: I got more stuff rattling with my older attempts, including the easy of easies, the Sonotube TL that got me started on this accursed hobby
Next time I should just buy a Danley perhaps.
For all those here who tried to help me, a word of thanks. My gift to you is this: I have temporarily satisfied my inner mad scientist (or become too embarrassed?) and will not likely undertake any new projects until I've recovered.
Attachments
Giving up (again)...
The Soldermizer is calling the latest build a failure. The "Blue Whale", is actually a white elephant! Various tweaks (Great Stuff foam) failed to damp the resonances that are most likely due to the hollow core doors used, but it could be due to the half-assed bracing I used. Who knows? The important thing is I was able to sa(l)vage the two Alpine 15" drivers. Only needed a screwdriver and hammer to remove them. So gorilla glue is not invincible! They don't appear damaged.
"Like a dog returneth to his vomit, the fool returneth to his folly." -- somewhere in the Good Book
Applied to my queasy DIY history, this means: why not resurrect Frankenclosure I (still serving as a coffee table, having not made it to the bonefire yet.) I will try my luck at a sealed cabinet, maybe add some more bracing. No additional materials needed and I can use my favorite Gorilla Glue to patching things together.
Lessons learned:
0. Not a damned thing!
1. Unconventional methods usualy give unconventional (and disappointing) results.
2. Would have-could have: If I'd had some way to inject concrete into the hollow core doors, I might have solved the resonance problem Why not just order a concrete septic tank for my next enclosure
3. I will go with sealed for a while until the DIY urge strikes again.
4. Name needed for the new one. Hmmm...to be determined.
5. The option still exists to do some horrible mutation of the El-Pipe-O: I have two big subs, a box, and still the currently-unused 10 1/2 12" sonotube and length of 12" flexible duct from earlier subwoofer builds.
[cue sounds of thunder and lightning and maniacal laugher reverberating in the basement]
The Soldermizer is calling the latest build a failure. The "Blue Whale", is actually a white elephant! Various tweaks (Great Stuff foam) failed to damp the resonances that are most likely due to the hollow core doors used, but it could be due to the half-assed bracing I used. Who knows? The important thing is I was able to sa(l)vage the two Alpine 15" drivers. Only needed a screwdriver and hammer to remove them. So gorilla glue is not invincible! They don't appear damaged.
"Like a dog returneth to his vomit, the fool returneth to his folly." -- somewhere in the Good Book
Applied to my queasy DIY history, this means: why not resurrect Frankenclosure I (still serving as a coffee table, having not made it to the bonefire yet.) I will try my luck at a sealed cabinet, maybe add some more bracing. No additional materials needed and I can use my favorite Gorilla Glue to patching things together.
Lessons learned:
0. Not a damned thing!
1. Unconventional methods usualy give unconventional (and disappointing) results.
2. Would have-could have: If I'd had some way to inject concrete into the hollow core doors, I might have solved the resonance problem
Why not just order a concrete septic tank for my next enclosure 3. I will go with sealed for a while until the DIY urge strikes again.
4. Name needed for the new one. Hmmm...to be determined.
5. The option still exists to do some horrible mutation of the El-Pipe-O: I have two big subs, a box, and still the currently-unused 10 1/2 12" sonotube and length of 12" flexible duct from earlier subwoofer builds.
[cue sounds of thunder and lightning and maniacal laugher reverberating in the basement]
Yes. After exactly a year of subwoofer perpetrating, I have learned a lot, mainly to listen to the smart ones. I have satisfied myself it is easy to assemble functional sub's ... Sonotube or flexible duct. Slightly more effort to build an appalling but effective cabinet. The fine craftsmanship I shall leave to you fine craftsmen!
After sitting around useless for most of the year, it suddenly occurred to me that why yes I could cut up the old failed subwoofer with a electric chainsaw. So I did that and now it is out waiting pick up by the trash people. Problem: they refused to pick it up!
An externally hosted image should be here but it was not working when we last tested it.
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