Scott and Dave has done a lots of work to create a beautiful work of art, starting with basic boxy design, shockingly simple to make (I am making one now just with a circular saw), they have created a curvy Chang cabinet.
Just beautiful and stylish.
I am hopeful all question re: Curvy Chang can be posted here so we can all follow.
gychang
original boxy Chang cabinet:
curvy Chang here:
Just beautiful and stylish.
I am hopeful all question re: Curvy Chang can be posted here so we can all follow.
gychang
original boxy Chang cabinet:
An externally hosted image should be here but it was not working when we last tested it.
curvy Chang here:
An externally hosted image should be here but it was not working when we last tested it.
One of the best looking designs yet
I really like the rendering by marce.
I'm still working on my Harvey's. If a curvy Harvey turns up, I may have to break down and build them just because they look so cool. I can't justify getting any more drivers right now otherwise I would build the Curvy Changs.
We'll have to work on the name though... Curvy Bruce, Curvy Harvey and Curvy Chang sounds like a couple of drag queens.
I really like the rendering by marce.
I'm still working on my Harvey's. If a curvy Harvey turns up, I may have to break down and build them just because they look so cool. I can't justify getting any more drivers right now otherwise I would build the Curvy Changs.
We'll have to work on the name though... Curvy Bruce, Curvy Harvey and Curvy Chang sounds like a couple of drag queens.
Some more numbers:
Curve radius 2011mm
Centre of curve to baffle: 28mm (1.1 inches)
narrow part in middle of side (Waist): 356mm
widest part of side: 511mm (7.2 inch extension)
Note: the side measurements are for a full depth side panel and a 240mm wide back panel.
For a recessed FE207E the driver brace is slightly less than 208mm deep. File it to fit then put some thin foam tape on it.
Curve radius 2011mm
Centre of curve to baffle: 28mm (1.1 inches)
narrow part in middle of side (Waist): 356mm
widest part of side: 511mm (7.2 inch extension)
Note: the side measurements are for a full depth side panel and a 240mm wide back panel.
For a recessed FE207E the driver brace is slightly less than 208mm deep. File it to fit then put some thin foam tape on it.
Hi again,
must agree with GYChang, as soon as I saw the curvy chang I fell in love with its looks.
I've downloaded the new plans and will ponder over them. (NB Dave, the way I drew them in inventor is what gave me the silly angle, I should have looked and realised that it would be impossible to build to that accuracy and a sensible angle would be appropiate.)
Thinking about the back mounted treble, what I think I'll do if I go that way is have a circular insert with the FT17 rear mounted that bolts into a recess in the baffle. This way it will be possible to extract the tweeter without much trouble.
must agree with GYChang, as soon as I saw the curvy chang I fell in love with its looks.
I've downloaded the new plans and will ponder over them. (NB Dave, the way I drew them in inventor is what gave me the silly angle, I should have looked and realised that it would be impossible to build to that accuracy and a sensible angle would be appropiate.)
Thinking about the back mounted treble, what I think I'll do if I go that way is have a circular insert with the FT17 rear mounted that bolts into a recess in the baffle. This way it will be possible to extract the tweeter without much trouble.
Full set of CAD plans for flat & curved builds are now up on the Frugal-horn site if anyone didn't know: http://www.frugal-horn.com/spawn.html -scroll down to near the bottom.
Marce, I like that idea. The horn assembly could be turned on a lathe easily. But how often would you need to extract the tweeter? If you had to replace it you could reach through the 180mm main driver hole.
If your're over 40 you may not need the tweeter with the FE206E. You high end hearing is most likely "relaxed" enough not to need it.
One question that hasn't been answered in detail is how to stuff it. "As a normal Bass reflex" was the answer. I must say loathe working with fibreglass and woll is hard to find here. I'd prefer polyester.
I'm guessing approx 20mm thick polyester on all internal surfaces, tacked in place with the odd staple. Keep it well clear of the ports, put a bit extra across the hump. Then it if sounds too dead tear it off one wall. Is that too much?
If your're over 40 you may not need the tweeter with the FE206E. You high end hearing is most likely "relaxed" enough not to need it.
One question that hasn't been answered in detail is how to stuff it. "As a normal Bass reflex" was the answer. I must say loathe working with fibreglass and woll is hard to find here. I'd prefer polyester.
I'm guessing approx 20mm thick polyester on all internal surfaces, tacked in place with the odd staple. Keep it well clear of the ports, put a bit extra across the hump. Then it if sounds too dead tear it off one wall. Is that too much?
I could have sworn I'd answered this somewhere -I must be getting old or something. I'd treat it as an MLTL & do what GM suggested to me for such boxes: line the internal top, rear (keeping the vents clear) and one sidewall with a suitable material, carpet underlay, stiff acoustic fibreglass like Bob Brines uses for his cabinets or something similar. That should do the job nicely.
Hi Dave,
i was being to clever for my own good, trying to set up a workplane using existing geomatry, a set of DWG,s or DXF's would be very usesful, if you dont mind, pre 2008 release cos I havn't loaded it yet.
If you have any drawings of the drive units, that would be a great help, and save me having to measure one of my FT17's, as I think I'll go for the rear mounted tweeter.
marcdotenglandatdeepseaplc.com
i was being to clever for my own good, trying to set up a workplane using existing geomatry, a set of DWG,s or DXF's would be very usesful, if you dont mind, pre 2008 release cos I havn't loaded it yet.
If you have any drawings of the drive units, that would be a great help, and save me having to measure one of my FT17's, as I think I'll go for the rear mounted tweeter.
marcdotenglandatdeepseaplc.com
Scottmoose said:
Greets!
I resemble those remarks! Also, due to the vent layout it's ideal for just lining the top and diagonally suspending a 'curtain' of insulation batting down to the bottom, with any additional fine tuning being done by the simple expedient of placing some on the bottom as required.
FYI, Owens-Corning Miraflex R-25 is an excellent 'itchless' fiberglass insulation alternative.
GM
I like rear mounted tweeters because they are hidden from view but are audible and adjustable. Wiring for the rear requires different caps etc to sound good compared to what would be used for forward facing.
But, some may not like rear mounting. Has anyone come up with interesting solutions for front mounting tweeters on speaker cabinets like this other than what TC did?
I thought of hanging the tweeter from the side. I will draw it up later to see if it sparks any better ideas.
Here's the idea...
http://www.zillaspeak.com/sidemountedtweeter.asp
It doesnt look pretty but it would work.
Godzilla
But, some may not like rear mounting. Has anyone come up with interesting solutions for front mounting tweeters on speaker cabinets like this other than what TC did?
I thought of hanging the tweeter from the side. I will draw it up later to see if it sparks any better ideas.
Here's the idea...
http://www.zillaspeak.com/sidemountedtweeter.asp
It doesnt look pretty but it would work.
Godzilla
apologies for not mentioning contribution from ronc and not attributing curvy Chang graphics to marce.
No problem, i am use to being forgotten. Kind of like being an offensive lineman (words of Dick Butkus).
The only drawback i can see with the BVR type alingments is the limited BW of the action. Thats why the Chang (or whatever) sims better on my programming is the larger baffle area produces a lower frequency hand-off. Actually even the slight inset and curve around the baffle is a slight horn loading.
ron
No problem, i am use to being forgotten. Kind of like being an offensive lineman (words of Dick Butkus).
The only drawback i can see with the BVR type alingments is the limited BW of the action. Thats why the Chang (or whatever) sims better on my programming is the larger baffle area produces a lower frequency hand-off. Actually even the slight inset and curve around the baffle is a slight horn loading.
ron
Godzilla.
Rear mounting in this case we're actually talking about putting the FT17H in the front baffle, but frob the back, extending the horn flare out to integrate smoothly into the front baffle.
I see three advantages: Closer acoustic centre to the main driver, less diffraction due to a smoother match with the baffle, hides that cheap looking chrome ring.
Speaking if diffraction and reflection, should felt or similar be applied to the inside edge of the curve around these drivers?
Planet10 drew this:
Rear mounting in this case we're actually talking about putting the FT17H in the front baffle, but frob the back, extending the horn flare out to integrate smoothly into the front baffle.
I see three advantages: Closer acoustic centre to the main driver, less diffraction due to a smoother match with the baffle, hides that cheap looking chrome ring.
Speaking if diffraction and reflection, should felt or similar be applied to the inside edge of the curve around these drivers?
Planet10 drew this:
Attachments
In any passive XO the secondary driver energy production plane will be closer to the listener as there is at least a 1/4 wavelength difference at a given frequency between the two drivers at the target XO point.
ron
. This is an evaluation of first order crossovers at a 90 deg phase change.
2. This is an evaluation of physical plane (vertical plane placement) of the energy producing points of two transducers.
3. This has impact on the order of wave points ( ie: points on a sine wave) and the time /distance of the arrival of the wave points to a given greater position.
If you look the given general concensus is that adding a first order crossover will give a 90 degree phase change. This means that the secondary transducer will see the signal at a later time than the first. The time that the second transducer will see the signal is based upon the V of the signal transfer circuit plus the added phase differential. I am not going into the " speed of electronic conductance" as this means very little in audio.
Given that at a 90 deg. phase difference that the signal will become effective the distance is:
dis=(V/F)/4.
where: dis= distance
V= velocity of the medium
F=frequency in Hertz
This is fairly simple as at 1/4 wavelength it is a 90 degree phase change. So the time/distance of the phase change is dependant on the velocity of the medium ( air) and the frequency.
Conclusion: Proper placement of the transducers in respect to the listener position should be taken into account for the difference for the phase point of the added delay of first order crossovers. Physical alignments of the planes of energy production should be adjusted for the phase difference.
ron
ron
. This is an evaluation of first order crossovers at a 90 deg phase change.
2. This is an evaluation of physical plane (vertical plane placement) of the energy producing points of two transducers.
3. This has impact on the order of wave points ( ie: points on a sine wave) and the time /distance of the arrival of the wave points to a given greater position.
If you look the given general concensus is that adding a first order crossover will give a 90 degree phase change. This means that the secondary transducer will see the signal at a later time than the first. The time that the second transducer will see the signal is based upon the V of the signal transfer circuit plus the added phase differential. I am not going into the " speed of electronic conductance" as this means very little in audio.
Given that at a 90 deg. phase difference that the signal will become effective the distance is:
dis=(V/F)/4.
where: dis= distance
V= velocity of the medium
F=frequency in Hertz
This is fairly simple as at 1/4 wavelength it is a 90 degree phase change. So the time/distance of the phase change is dependant on the velocity of the medium ( air) and the frequency.
Conclusion: Proper placement of the transducers in respect to the listener position should be taken into account for the difference for the phase point of the added delay of first order crossovers. Physical alignments of the planes of energy production should be adjusted for the phase difference.
ron
I'm going passive to start with, then when I find or build a nice 5-10W amp at the right price I will bi-amp it with an active crossover. I nearly bought a behringer crossover but it won't go higher than 9.3kHz so I'll have to build one. I like the idea of that transformer coupled high voltage solid state amp you mentioned elsewhere Ron.
The fancy digital Behringer Xover has delay adjustment but I'm wary of that much digital processing of the signal.
It's good you pointed that out ron, some might have been thinking that the time alignment might have worked with passive XO
The fancy digital Behringer Xover has delay adjustment but I'm wary of that much digital processing of the signal.
It's good you pointed that out ron, some might have been thinking that the time alignment might have worked with passive XO
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