I made this out of poster board paper
With the Selenium horn in back it was pretty narrow up and down, but 180 degrees across. Sounded pretty amazing too. I did the potato masher because it's easier to build than the zig-zag louver type. The flat louver lens is pretty large. They all sound quite good. JBL and every one else moved to constant directivity horns because they could be cast from plastic cheap, not because they sounded any good. The JBL lenses had each plate a different hole pattern for the hardware stack up.
With the Selenium horn in back it was pretty narrow up and down, but 180 degrees across. Sounded pretty amazing too. I did the potato masher because it's easier to build than the zig-zag louver type. The flat louver lens is pretty large. They all sound quite good. JBL and every one else moved to constant directivity horns because they could be cast from plastic cheap, not because they sounded any good. The JBL lenses had each plate a different hole pattern for the hardware stack up.
don't forget for treble to try a K-tube. for a one-inch format driver - use 1"ID pipe or rolled paper, etc. half-ellipse shape ~5.3" long with 1/8" starting gap. Elevate the tube somewhat above horizontal (assuming the slot is "down"). I have some Karlson "X15" with original CTS woofer and clones of one set of metal K-tube - they measure rough partly due to diameter transitions -going from 1" driver exit to a funky inner piece which is sliced then to 1.8" or so ID aluminum tube with parabolic slot. They sound very much like a plate lens IIRC.
make your tube kinda like this
make your tube kinda like this
An externally hosted image should be here but it was not working when we last tested it.
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Are you talking about this MLTL?
The vent CSA is 2.4 in^2 and you want to use a 1.38in inside dia round pipe? I would normally run a sim in Akabak and check but my computer is still down. Ignoring wall drag on pipe vs rectangular slot, the area and length are inversely proportional. So I estimate length of 1.38in dia pipe to be 1.66 in long for same tuning.
I'm basicly talking about that wall-mltl.
All in all this good news as this will allow me some very welcome adjustments I have not finished the build yet.
I'm working very carefully to not damage the print on the front-plate.
A 11litre cabinet and a 3.5cm dia pipe which is 4cm long gives me a tuning of about 60Hz.
Right?
Will this be too high?
If a bass reflex program says 60Hz that is perfect. I have found the MLTL action will bring it about 5Hz lower than the BR prediction. So you will probably end up measuring a 55Hz bass corner.
check this out
these might be a good candidate for a scale down foamboard version :
Ampeggio Due Acryl - Voxativ Loudspeakers
these might be a good candidate for a scale down foamboard version :
Ampeggio Due Acryl - Voxativ Loudspeakers
Thanks for the link - that is indeed and interesting design and probably good for wall mount. Very easy to make in foam core - and I have just the driver to try - the new Dayton PS95-8. Now, I just need to find some time as I have a couple of other projects going.
An externally hosted image should be here but it was not working when we last tested it.
It really probably won't be too different from my Flat BIB design in sound.
The KaZba dual 8 inch is up and running. More info here:
http://www.diyaudio.com/forums/full-range/271011-rockin-kazba-dipole-k-aperture-z-baffle-dipole.html
Sound clips here:
http://www.diyaudio.com/forums/full-range/271011-rockin-kazba-dipole-k-aperture-z-baffle-dipole-6.html#post4270896
It sounds fantastic in a FAST with the Nautaloss on top.
http://www.diyaudio.com/forums/full-range/271011-rockin-kazba-dipole-k-aperture-z-baffle-dipole.html
Sound clips here:
http://www.diyaudio.com/forums/full-range/271011-rockin-kazba-dipole-k-aperture-z-baffle-dipole-6.html#post4270896
It sounds fantastic in a FAST with the Nautaloss on top.
I just started experimenting with speaker building and I love the foam-core method of quickly prototyping. Thanks xrk971.
I can hardly keep up with all the exotic builds described in this thread, but I thought I'd report on the few mundane builds with cheap speakers that I did (see pics).
1. FH2 enclosure, FE83 driver (height reduced to 30 inches)
2. Ad-hoc enclosure, topology derived from this thread, FE83 driver
3. TABAQ, TB W3 1053SC driver (also height reduced to 30 inches)
The 30 inch height is a consequence of the foam board dimension and my laziness. And I didn't include a BSC circuit.
I don't have any measurements (no decent mic yet), but I'll give my subjective impressions. The FH2 sounded excellent, clear mids and highs with a healthy full bass. The ad-hoc enclosure sounded almost as good, with just slightly less bass. For both the above, the higher notes were bright and forward, to the point where some people may describe them as harsh. The TABAQ was quite disappointing in the bass department - very weak, but the mids and highs were clear and in no way harsh.
Comments are welcome. Also, I have a couple of FE85's waiting for an enclosure. I'd be glad of any suggestions.
Also, if anyone has any recommendations for a decent mic for making measurements, I'd love to hear them.
I can hardly keep up with all the exotic builds described in this thread, but I thought I'd report on the few mundane builds with cheap speakers that I did (see pics).
1. FH2 enclosure, FE83 driver (height reduced to 30 inches)
2. Ad-hoc enclosure, topology derived from this thread, FE83 driver
3. TABAQ, TB W3 1053SC driver (also height reduced to 30 inches)
The 30 inch height is a consequence of the foam board dimension and my laziness. And I didn't include a BSC circuit.
I don't have any measurements (no decent mic yet), but I'll give my subjective impressions. The FH2 sounded excellent, clear mids and highs with a healthy full bass. The ad-hoc enclosure sounded almost as good, with just slightly less bass. For both the above, the higher notes were bright and forward, to the point where some people may describe them as harsh. The TABAQ was quite disappointing in the bass department - very weak, but the mids and highs were clear and in no way harsh.
Comments are welcome. Also, I have a couple of FE85's waiting for an enclosure. I'd be glad of any suggestions.
Also, if anyone has any recommendations for a decent mic for making measurements, I'd love to hear them.
Attachments
Udoitall,
Fantastic work! I haven't seen anyone besides Jim Shearer and Bcmbob who are brave enough to try the homage to the the FH3. Looks very nice - surprised it works with the Fountek FE85.
If you want a good speaker to try - make the 0.4x Karlsonator - but I recommend you buy some Vifa TC9FD's. A much better driver for smooth mids and nice highs with good bass extension. The Faital Pro 3FE25 is also an excellent driver. I avoid aluminum comes due to fact that they tend to ring and sound sibilant.
Fantastic work! I haven't seen anyone besides Jim Shearer and Bcmbob who are brave enough to try the homage to the the FH3. Looks very nice - surprised it works with the Fountek FE85.
If you want a good speaker to try - make the 0.4x Karlsonator - but I recommend you buy some Vifa TC9FD's. A much better driver for smooth mids and nice highs with good bass extension. The Faital Pro 3FE25 is also an excellent driver. I avoid aluminum comes due to fact that they tend to ring and sound sibilant.
Thanks. Gotta pay homage to the FH3. Just one of those things that's the right thing to do.
And it sounds great!I'm sold - Vifa's on the way, but I can't wait, I'm going to try the 0.4x Karlsonator with the FE85's I have lying around. I'm particularly keen to try a Karlson type build because of some plans I have for building outside speakers this summer - see this post
and this thread.
By the way, I'd like to try some of these builds in a FAST configuration. Any recommendations for driver and enclosure for the subwoofer? Preferably foam-core prototypable
?
Here is a good foam core sub I am currently using for FAST:
http://www.diyaudio.com/forums/full-range/268524-xki-xs-ab-initio-karlson-6th-order-bandpass-26.html#post4226956
Those drivers are no longer available but you could easily adapt design to dual MCM 55-2421's as XKi or as simple PP slot loaded 6th order as shown here:
http://www.diyaudio.com/forums/subwoofers/258433-light-air-slot-loaded-band-pass-sub.html
There is a plan by TB46 in that thread for the dual MCM's.
There is also this really cool design with dual 55-2421's:
http://www.diyaudio.com/forums/attachments/subwoofers/429073d1405690957-light-air-slot-loaded-band-pass-sub-xrk971_55-2421_ppsl_short.pdf
For subs with 8in driver use at least 3/4in XPS foam insulation sheathing. Or laminate of foam core cardboard foam core sandwich.
http://www.diyaudio.com/forums/full-range/268524-xki-xs-ab-initio-karlson-6th-order-bandpass-26.html#post4226956
Those drivers are no longer available but you could easily adapt design to dual MCM 55-2421's as XKi or as simple PP slot loaded 6th order as shown here:
http://www.diyaudio.com/forums/subwoofers/258433-light-air-slot-loaded-band-pass-sub.html
There is a plan by TB46 in that thread for the dual MCM's.
There is also this really cool design with dual 55-2421's:
http://www.diyaudio.com/forums/attachments/subwoofers/429073d1405690957-light-air-slot-loaded-band-pass-sub-xrk971_55-2421_ppsl_short.pdf
For subs with 8in driver use at least 3/4in XPS foam insulation sheathing. Or laminate of foam core cardboard foam core sandwich.
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This is a good place to start on how to make a simple FAST with a miniDSP and foam core:
http://www.diyaudio.com/forums/full-range/249984-cheap-fast-ob-literally.html
http://www.diyaudio.com/forums/full-range/249984-cheap-fast-ob-literally.html
I'm moving to an island on the other side of the world for a couple of years soon and have been contemplating my options on bringing a decent sounding system with me. Shipping runs about $2.50 a pound, freight gets handled fairly roughly, and I'll have to pay to ship them back home or leave them behind, so a pair of 50 pound towers is out of the question.
I'm considering shipping a pair of TC9FDs with the intent of making a pair of mini-karls once I'm on the island. How long can I expect a pair of foam core "cabinets" to last? I hope to get a couple of years out of them and I'm toying with the idea of using a Gorilla Glue/construction adhesive to bolster the hot glue to help out with durability. Is this even necessary?
I'm considering shipping a pair of TC9FDs with the intent of making a pair of mini-karls once I'm on the island. How long can I expect a pair of foam core "cabinets" to last? I hope to get a couple of years out of them and I'm toying with the idea of using a Gorilla Glue/construction adhesive to bolster the hot glue to help out with durability. Is this even necessary?
Mine have lasted 2 years indoors. If humid island environment, maybe spray the foam core with art spray on protective lacquer. Make sure it is foam safe and doesn't melt foam. Another is water-based waterproof clear acrylic paint used for wood projects. Just paint on - or use colorful paint to make it any color you want.
Bring more than a pair of TC9FD's maybe 6, they are small and light. Bring a hot melt glue gun and 3 bags of glue sticks, that should last you.
Another great driver to bring is Faital Pro 3FE25. Kind of like TC9FD in smoothness but 6dB more sensitive.
Bring a couple of TPA3116D2 amp boards or TDA7492 amp boards and laptop bricks.
Bring some utility knives, a ruler, wire crimpers, crimp quick disconnects for speaker tabs, speaker wire, cheap binding posts or cheap $1 terminal cups with spring clips, you can have lots of fun.
Bring more than a pair of TC9FD's maybe 6, they are small and light. Bring a hot melt glue gun and 3 bags of glue sticks, that should last you.
Another great driver to bring is Faital Pro 3FE25. Kind of like TC9FD in smoothness but 6dB more sensitive.
Bring a couple of TPA3116D2 amp boards or TDA7492 amp boards and laptop bricks.
Bring some utility knives, a ruler, wire crimpers, crimp quick disconnects for speaker tabs, speaker wire, cheap binding posts or cheap $1 terminal cups with spring clips, you can have lots of fun.
Thanks. Gotta pay homage to the FH3. Just one of those things that's the right thing to do.
I'm sold - Vifa's on the way, but I can't wait, I'm going to try the 0.4x Karlsonator with the FE85's I have lying around. I'm particularly keen to try a Karlson type build because of some plans I have for building outside speakers this summer - see this post
and this thread.
By the way, I'd like to try some of these builds in a FAST configuration. Any recommendations for driver and enclosure for the subwoofer? Preferably foam-core prototypable
Any luck on the 0.4x K's?