* POP *
[Sound effect of a head being pulled out of a dark, smelly place ]
Unless I'm wrong, I can build at least a basic rectangular "horn" with butt joints and regular 90 degree cuts. Only two pieces need to be trapezoid shaped. Yes, the mouth and throat will not be flush but that is easier to smooth out. The important parts to join are the petals of the horn and I believe basic glue and screw will work?
[Sound effect of a head being pulled out of a dark, smelly place ]
Unless I'm wrong, I can build at least a basic rectangular "horn" with butt joints and regular 90 degree cuts. Only two pieces need to be trapezoid shaped. Yes, the mouth and throat will not be flush but that is easier to smooth out. The important parts to join are the petals of the horn and I believe basic glue and screw will work?
The butt joints on the trapezoid shaped parts will not be 90 degree, they are closer to 45 degree for a 90 degree horn.
Bwaslo's Synergy calculator (linked at the bottom of his post in #10) will give you all the cut angles of a two part Synergy style horn of any desired size and dispersion.
I'm probably misusing the term "butt joint." I mean that the trapezoid piece will be cut at an angle (to the horizontal) but the cut is vertical (correct term?) and thus can be done with a humble jigsaw or other entry level power tool
I'm not planning a two-expansion Unity style horn at first; I agree that the calculator is the way to go if I have a real horn built, but that requires a real shop with real skills
I'm not planning a two-expansion Unity style horn at first; I agree that the calculator is the way to go if I have a real horn built, but that requires a real shop with real skills
A butt joint is a flush connection of two parts. A dado joint has a cut out so one part fits in a slot or "L" shaped cut out.I'm probably misusing the term "butt joint." I mean that the trapezoid piece will be cut at an angle (to the horizontal) but the cut is vertical (correct term?) and thus can be done with a humble jigsaw or other entry level power tool
You can build square or rectangular boxes using all 90 degree cuts, but not a horn.
If your jigsaw blade angle can be adjusted, the angle required for a flush butt joint in a conical horn can be accomplished with it. If it is a fixed 90 degree angle saw, you would need to use expanding glue to fill the void.
In the picture below you can see side baffle angles are 90 degree (other than the end that attaches to the HF driver baffle plate). The angle for the trap shaped lower horn part is slight, but definitely not 90 degree. If cut to 90 degree, the left part of the horn would "lean in" at the top when assembled. If you could hold it at the proper angle while gluing and screwing (very difficult to accomplish when the cut angle is not correct) there would be a gap on inside of the horn, the parts won't "butt" together.
Attachments
I'm probably misusing the term "butt joint." I mean that the trapezoid piece will be cut at an angle (to the horizontal) but the cut is vertical (correct term?) and thus can be done with a humble jigsaw or other entry level power tool
I'm not planning a two-expansion Unity style horn at first; I agree that the calculator is the way to go if I have a real horn built, but that requires a real shop with real skills
It doesn't really require much of a shop. I only have a $50 used craigslist table saw on a stand I drag out onto the pavement when I need to do some cutting. A tablesaw and a pair home-made sled boards can do amazing things even with my very ham-handed carpentry skills.
On smoothing the countours, keep in mind the wavelengths being effected and what parts of the waveguide control which frequency/wavelength bands. The higher frequency control is pretty much set in the first five or so inches of horn length (above 13kHz or so is almost entirely set inside the tweeter driver!) , so shapes further out only have much effect on longer wavelengths. The point being that shape irregularites that are small compared to a wavelength don't really do much out there. An edge that sticks out say just an eighth of an inch 6 inches down the horn is going to be pretty much benign and not worth worrying about other than maybe for cosmetics.
03-26-16 Philosophical phlatulations on current build
I’m quite happy with my SM-100-clones. They are functional, kinda-sorta sealed (foam and backer rod to mate the driver to the cone horn.); I am still adding sticks for a base and for strengthening the attachment of the waveguide to the driver enclosure.
I will listen to them for a month, April is conveniently 30 days, and then see what I’d wish to do next. Probably build a more permanent, even wooden, enclosure J
I found that Tampa has a "Maker" type club where toys such as fully equipped wood shop and even 3-D printer and CNC available. Hmmm......
The limitations of my DIY –or- justifying a lazy build
It’s worth noting that Danley offers several models that have coaxial drivers as part of – or the sole – driver in an enclosure. My current build looks to the SM-100 for inspiration. This model, based on the photos, appears to be “just” an 8” coax in the molded case (with a ported enclosure). In contrast, the SM-100’s mid/hi is a 5” coax but one of Danley’s designs (the only?) that cleverly adapts the coaxial to a “normal” conical horn, then he pipes the “woofer” part of the coax into injection ports at the appropriate places in “his” horn.
Lacking any hard data, the following is just speculation, but well informed J
The SM-60 will be a closer match to the Synergy ideal than the SM-100, without the special plumbing at the coaxial. How, and to what extent, this impacts the overall response of a driver is unclear right now.
It’d be fascinating to see an A-B comparison of (say) the SM-60 with and without its “plumbing.” Of course, it’d be nice to see detailed polars, etc. of Danley’s goods but I am not aware of these being available.
From reading about a coaxial driver’s good and bad points, it appears the worst is the intermodualtion distortion between the cone and the HF units. This is minimized to some degree by clever engineering. I have assumed by paying a premium price for my BMS coax that fine German engineering has solved all these issues J Not. If that were true, then Danley would have no need of the plumbing for the SM-60. Counter-argument: having solved that issue on one model, why would he not do the same for the plumbing-less SM-100 and similar? It would add almost nothing to the cost of injection-molded plastic. A reasonable guess is that the coax’s IM and perhaps other distortions isn’t that great an issue.
Ultimately, my best argument for the use of a coaxial is that it greatly simplifies building a psuedo-Synergy box. The spacing between HF and “mids” is fixed; no ports to drill; crossover is not included, I am using active. Tune to taste (time delay, x-over, etc.) I see no reason that Danley’s ¼ wave distance is violated.
It does impose limits on how the horn is built. My first attempt did not care much for these but it seems for a “real” effort, I would:
Try to better determine where the apex of the horn will be.
Make the whole horn’s profile 90 degrees, as that is what the BMS coax uses.
Make the transition from the circle to the square much smoother (probably with putty next time, hand-molded, sanded, etc.)
TBD: Since the coax is by definition an all-in-one unit, it should greatly ease the mounting and design of the throat and enclosure(s).
One option I’ll explore is this: design the wooden waveguide to resemble the standard Unity (but 90 rather than 60 degrees?) and make the apex suitable for an itty-bitty driver (1” or whatever). Obviously an 8” coax won’t fit there, but why can’t I mount it on an 8x8” square which is then affixed tightly as deep into the horn as practical?
Con: there may not be enough rear chamber volume (I am assuming sealed chamber.) This can be estimated before making saw dust.
Pro: an entire “horn” is available if later I want to remove the coaxial and use other drivers, for something closer to a true Unity or Synergy clone.
I’m quite happy with my SM-100-clones. They are functional, kinda-sorta sealed (foam and backer rod to mate the driver to the cone horn.); I am still adding sticks for a base and for strengthening the attachment of the waveguide to the driver enclosure.
I will listen to them for a month, April is conveniently 30 days, and then see what I’d wish to do next. Probably build a more permanent, even wooden, enclosure J
I found that Tampa has a "Maker" type club where toys such as fully equipped wood shop and even 3-D printer and CNC available. Hmmm......
The limitations of my DIY –or- justifying a lazy build
It’s worth noting that Danley offers several models that have coaxial drivers as part of – or the sole – driver in an enclosure. My current build looks to the SM-100 for inspiration. This model, based on the photos, appears to be “just” an 8” coax in the molded case (with a ported enclosure). In contrast, the SM-100’s mid/hi is a 5” coax but one of Danley’s designs (the only?) that cleverly adapts the coaxial to a “normal” conical horn, then he pipes the “woofer” part of the coax into injection ports at the appropriate places in “his” horn.
Lacking any hard data, the following is just speculation, but well informed J
The SM-60 will be a closer match to the Synergy ideal than the SM-100, without the special plumbing at the coaxial. How, and to what extent, this impacts the overall response of a driver is unclear right now.
It’d be fascinating to see an A-B comparison of (say) the SM-60 with and without its “plumbing.” Of course, it’d be nice to see detailed polars, etc. of Danley’s goods but I am not aware of these being available.
From reading about a coaxial driver’s good and bad points, it appears the worst is the intermodualtion distortion between the cone and the HF units. This is minimized to some degree by clever engineering. I have assumed by paying a premium price for my BMS coax that fine German engineering has solved all these issues J Not. If that were true, then Danley would have no need of the plumbing for the SM-60. Counter-argument: having solved that issue on one model, why would he not do the same for the plumbing-less SM-100 and similar? It would add almost nothing to the cost of injection-molded plastic. A reasonable guess is that the coax’s IM and perhaps other distortions isn’t that great an issue.
Ultimately, my best argument for the use of a coaxial is that it greatly simplifies building a psuedo-Synergy box. The spacing between HF and “mids” is fixed; no ports to drill; crossover is not included, I am using active. Tune to taste (time delay, x-over, etc.) I see no reason that Danley’s ¼ wave distance is violated.
It does impose limits on how the horn is built. My first attempt did not care much for these but it seems for a “real” effort, I would:
Try to better determine where the apex of the horn will be.
Make the whole horn’s profile 90 degrees, as that is what the BMS coax uses.
Make the transition from the circle to the square much smoother (probably with putty next time, hand-molded, sanded, etc.)
TBD: Since the coax is by definition an all-in-one unit, it should greatly ease the mounting and design of the throat and enclosure(s).
One option I’ll explore is this: design the wooden waveguide to resemble the standard Unity (but 90 rather than 60 degrees?) and make the apex suitable for an itty-bitty driver (1” or whatever). Obviously an 8” coax won’t fit there, but why can’t I mount it on an 8x8” square which is then affixed tightly as deep into the horn as practical?
Con: there may not be enough rear chamber volume (I am assuming sealed chamber.) This can be estimated before making saw dust.
Pro: an entire “horn” is available if later I want to remove the coaxial and use other drivers, for something closer to a true Unity or Synergy clone.
Tampa HackerSpace Visit
Tonight I visited my local "HackerSpace" down in Tamper.
Tampa Hackerspace ? 4931 W. Nassau St., Tampa, FL 33607
I endured a business meeting, but then got to meet several members who shared some of their projects with me. I got a quick tour of the wood shop. They also have CNC, a laser cutter, 3-D printers, and a machine shop. They are presenting this Saturday at a "HackerCon" also in Tampa, which I plan to attend. While I haven't joined yet, the idea of having access to high tech tools, as well as an unpredictable pool of very talented people (many engineers there, software geeks, etc.) for $50/mo. or whatever is increasingly alluring. A well executed Synergy horn pair might be in my future after all. Not only that, but I may be able to corrupt others into the hobby of audio and if my mooching skills will allow, I will have them doing the hard work for poor, dumb old me (this works better when you're a 21-year-old blonde, rather than a 54-year-old graying geek...).
Guys, if you live near a major metro area, you owe it to yourself to consider a similar club. You'll still be able to get away from the wife, but she'll have a harder time tracking you down (just tell 'em you're at the bar ). While there is a certain pride of ownership and bragging rights in owning tools, do you really need $100,000 worth of workshop to build a $2000 pair of speakers
Tonight I visited my local "HackerSpace" down in Tamper.
Tampa Hackerspace ? 4931 W. Nassau St., Tampa, FL 33607
I endured a business meeting, but then got to meet several members who shared some of their projects with me. I got a quick tour of the wood shop. They also have CNC, a laser cutter, 3-D printers, and a machine shop. They are presenting this Saturday at a "HackerCon" also in Tampa, which I plan to attend. While I haven't joined yet, the idea of having access to high tech tools, as well as an unpredictable pool of very talented people (many engineers there, software geeks, etc.) for $50/mo. or whatever is increasingly alluring. A well executed Synergy horn pair might be in my future after all. Not only that, but I may be able to corrupt others into the hobby of audio and if my mooching skills will allow, I will have them doing the hard work for poor, dumb old me
(this works better when you're a 21-year-old blonde, rather than a 54-year-old graying geek...).Guys, if you live near a major metro area, you owe it to yourself to consider a similar club. You'll still be able to get away from the wife, but she'll have a harder time tracking you down (just tell 'em you're at the bar
). While there is a certain pride of ownership and bragging rights in owning tools, do you really need $100,000 worth of workshop to build a $2000 pair of speakers
A little T & A ... Brief tangent: Thermoacoustics
Yet more useless (to me) wisdom learnt from being too close to engineers
I'd never heard of "thermoacoustics", among other things, a type of refrigeration. Based on my "research" (one article), it would compete economically with a typical home refrigerator, but more difficult scaling to larger systems. It is related to audio because you need an acoustic source to make it work.
https://en.wikipedia.org/wiki/Thermoacoustic_heat_engine
I'm not aware of any commercial products, but ... Mr. Danley, you once made a ball of molten matter levitate on a sound wave; perhaps it's time you design us a new a/c or fridge. After all, it gets pretty hot down in Georgia....
How about a speaker that cools our beer
Yet more useless (to me) wisdom learnt from being too close to engineers
I'd never heard of "thermoacoustics", among other things, a type of refrigeration. Based on my "research" (one article), it would compete economically with a typical home refrigerator, but more difficult scaling to larger systems. It is related to audio because you need an acoustic source to make it work.
https://en.wikipedia.org/wiki/Thermoacoustic_heat_engine
I'm not aware of any commercial products, but ... Mr. Danley, you once made a ball of molten matter levitate on a sound wave; perhaps it's time you design us a new a/c or fridge. After all, it gets pretty hot down in Georgia....
How about a speaker that cools our beer
Obviously not, but it could allow a DIYer to create a $2k design with a fit, finish worthy of a $20 k retail pair, which would give your friends a serious case of envy that's priceless!
GM
Ghost speakers -- DSL's Go-2 line...
I stumbled upon these while googling coaxial stuff: Curiously, Danley has a line of speakers called the Go-2 that do not appear on his web site. I've looked a few times, and they are invisible. But maybe I'm just an Ijit
Danley Sound Labs Go-2 Series
I stumbled upon these while googling coaxial stuff: Curiously, Danley has a line of speakers called the Go-2 that do not appear on his web site. I've looked a few times, and they are invisible. But maybe I'm just an Ijit
Danley Sound Labs Go-2 Series
Why (maybe) Danley uses ports w/ coaxes not always
I had previously asked basically, of the DSL speakers that have a coaxial (cone) driver, why there is one that uses a variation of the Unity, Synergy patent (mids go through a port hole), this is the SM60M; but then there are others (e.g. the SM100) that appear to be a regular 8" coaxial with no special Unity magic.
Here is a post that clarifies why the SM60M used a 5" coax, and not an 8":
http://www.diyaudio.com/forums/multi-way/168903-tapped-horn-feeding-unity-horn.html#post2221575
Left unanswered is my question as to how the two variants of coax implementation fare in polar and other measurements.
I had previously asked basically, of the DSL speakers that have a coaxial (cone) driver, why there is one that uses a variation of the Unity, Synergy patent (mids go through a port hole), this is the SM60M; but then there are others (e.g. the SM100) that appear to be a regular 8" coaxial with no special Unity magic.
Here is a post that clarifies why the SM60M used a 5" coax, and not an 8":
http://www.diyaudio.com/forums/multi-way/168903-tapped-horn-feeding-unity-horn.html#post2221575
Left unanswered is my question as to how the two variants of coax implementation fare in polar and other measurements.
The SM100 and SH100 use a short horn extending the 8". Using a co-ax reduces the parts count and ease of construction, but still has the HF behind the LF, which with the Synergy passive crossover design still results in smooth phase response. The wide dispersion horn results in a shallow cabinet that fits it's typical application, down firing above a preacher for the SH100, or as a floor monitor (SM100).
Polar response of the SH100 narrows more in the HF than the more usual Synergy speakers due to the horn geometry, and frequency response is not as smooth.
Polar response for many of the DSL products are available on their website in the EASE format IIRC, which requires a Windows machine for viewing.
Attachments
Tamper MakerCon report
Weltersys, thanks! You've provided a, well, "welter" of information. I haven't tried the EASE viewer but yes on the CLD viewer. AS is the horn described, also "shallow" is my understanding of a lot of the finer details of the data viewers. I've never played on stage (nor been a preacher
) but I think my coax knock-off should be refined for home use
Intrigued by the hacker/maker option, I attended this function at the sorta-local state fairground. They had everything from a live steel drum band (music camp for rich white children ), to "Ghostbusters" truck, to electric go-kart race, to the more typical hacker stuff like mini-robots, competitions, educational stuff for demos at schools and so on. There even was a 3-D printer created in part with 3-d printer made parts Applicable to audio DIY, the HackerSpace stuff (3-d Printer, wood shop, etc.) + some prototyping kits for circuits would be most applicable.* Honorable mention to the old guy who automated a miniature home brewery 
* Sorry! I am being redundant, and repeating myself.
Here is a photo of the closest thing to a speaker I saw. It's the drain in the men's room
Weltersys, thanks! You've provided a, well, "welter" of information. I haven't tried the EASE viewer but yes on the CLD viewer. AS is the horn described, also "shallow" is my understanding of a lot of the finer details of the data viewers. I've never played on stage (nor been a preacher
) but I think my coax knock-off should be refined for home use Intrigued by the hacker/maker option, I attended this function at the sorta-local state fairground. They had everything from a live steel drum band (music camp for rich white children
), to "Ghostbusters" truck, to electric go-kart race, to the more typical hacker stuff like mini-robots, competitions, educational stuff for demos at schools and so on. There even was a 3-D printer created in part with 3-d printer made parts Applicable to audio DIY, the HackerSpace stuff (3-d Printer, wood shop, etc.) + some prototyping kits for circuits would be most applicable.* Honorable mention to the old guy who automated a miniature home brewery * Sorry! I am being redundant, and repeating myself.
Here is a photo of the closest thing to a speaker I saw. It's the drain in the men's room
Attachments
Last edited:
Subwoofer survey
Is your subwoofer loud enough? Here are some questions to ask.
1. The people one house over complain about the racket.
2. The people one county over complain.
3. Twenty-something punks driving in their street rods with one-note 1000 watt subs thumping away, complain about YOUR noise.
4. Wife acceptance factor isn't a factor, and you did not even notice she'd left you until you found a divorce court summons nailed to your front door.
5. Your local electrical grid experiences brown-outs in sync with beats and explosions from your home theatre.
6. The nearest military munitions range complains about the noise.
Sent from my NV570P using Tapatalk
Is your subwoofer loud enough? Here are some questions to ask.
1. The people one house over complain about the racket.
2. The people one county over complain.
3. Twenty-something punks driving in their street rods with one-note 1000 watt subs thumping away, complain about YOUR noise.
4. Wife acceptance factor isn't a factor, and you did not even notice she'd left you until you found a divorce court summons nailed to your front door.
5. Your local electrical grid experiences brown-outs in sync with beats and explosions from your home theatre.
6. The nearest military munitions range complains about the noise.
Sent from my NV570P using Tapatalk
- Status
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