How tolerant is foamcore to heat, as in an auto? It would be neat to have a pair of Karlsonators as rear speakers.
I don't think it can handle intense sun heating and cooling. It would peel and warp is my guess. In a car just get a high Qts driver and mount in a panel cutout.
Lance in Foam Core with RS100-4
I have always been a fan of Scottmoose's Lance TL, designed for the FF85wk. I decided to have a go at in foam core. It is a very small speaker about 10in tall x 7 in deep x 4 in wide. Plan for it is here:
http://wodendesign.com/downloads/Woden-FF85-Lance-Laby-1v01-180214.pdf
About 1.25 sheets of 30x20in foam core is enough to make a pair of speakers. The pieces are relatively easy to cut as they are all rectangles. I added some bracing which is needed for thin foam core but not if using 1/2in ply.
Here is the build process (took 2 hrs to make)...
Cut all the pieces for a pair of speakers:
Glue walls and dividers together (note cardboard layer for driver mounting):
Finished - a smart looking desktop speaker:
Here are the measurements 6 in away from a back wall:
Here is the measurement far from a wall:
Here is the output from the rear TL vent:
I can highly recommend this build - sounds very nice. Just don't push low frequencies or you approach 100% HD below 50Hz. 🙂
It sounds very nice, the bass extension is around the 80Hz range and although is not quite as deep as a 0.4x Karlsonator (70Hz), it is very satisfying to listen to. The intended use is as a desktop computer monitor 6 in away from a back wall so there is no need for BSC. A fun speaker and very easy to make.
I have always been a fan of Scottmoose's Lance TL, designed for the FF85wk. I decided to have a go at in foam core. It is a very small speaker about 10in tall x 7 in deep x 4 in wide. Plan for it is here:
http://wodendesign.com/downloads/Woden-FF85-Lance-Laby-1v01-180214.pdf
About 1.25 sheets of 30x20in foam core is enough to make a pair of speakers. The pieces are relatively easy to cut as they are all rectangles. I added some bracing which is needed for thin foam core but not if using 1/2in ply.
Here is the build process (took 2 hrs to make)...
Cut all the pieces for a pair of speakers:
Glue walls and dividers together (note cardboard layer for driver mounting):
Finished - a smart looking desktop speaker:
Here are the measurements 6 in away from a back wall:
Here is the measurement far from a wall:
Here is the output from the rear TL vent:
I can highly recommend this build - sounds very nice. Just don't push low frequencies or you approach 100% HD below 50Hz. 🙂
It sounds very nice, the bass extension is around the 80Hz range and although is not quite as deep as a 0.4x Karlsonator (70Hz), it is very satisfying to listen to. The intended use is as a desktop computer monitor 6 in away from a back wall so there is no need for BSC. A fun speaker and very easy to make.
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So far, I have not sold any, you interested? Most get stored, many wait about in the speaker lab for their turn again. I use many as MP3 player speakers in other parts of the house.
No. I have a bunch speakers I need to design enclosures for. I've just been too lazy to do so.
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I like that small design. Would anyone be able to comment on this vs. the Kanspea that Madisound sells? The Kanspea cabinets add very little cost as part of the kit when buying the drivers. These would be for my office, driven with a 3116 amp, or possibly my other daughter would take these to school for her dorm room.
You probably should ask that in the Woden 3 inch designs thread. I haven't tried any Fostex drivers so can't comment. The TL would sound better is my guess. Although I have also designed a dual chamber reflex (DCR) for the RS100-4 in the exact same footprint (very small) as the above box and it reaches deeper to 67Hz fb. Output will be down a bit but for near range at a desk it's not an issue. I can post plans if you are interested. I was actually going to build FC prototype but haven't had a chance yet.
These are terrible photos taken with my phone of my MLTL builds.
They're out of 3mm MDF as foamcore is elusive and expensive here.
I tried one in stereo and really liked it, so I built another and am running each as a single channel driven by two Sure TA2024 amps.
I am waiting for two Sure 3116 amps to try. They are hanging in my workshop.
Thanks X.
Paul
They're out of 3mm MDF as foamcore is elusive and expensive here.
I tried one in stereo and really liked it, so I built another and am running each as a single channel driven by two Sure TA2024 amps.
I am waiting for two Sure 3116 amps to try. They are hanging in my workshop.
Thanks X.
Paul
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Coit,
Very nice work! Interesting to use each as a speaker for stereo. Do you have any horizontal comb effects with two full range drivers space that far apart?
Very nice work! Interesting to use each as a speaker for stereo. Do you have any horizontal comb effects with two full range drivers space that far apart?
None whatsoever.The room is about 6.3mx5.7mx2.5m.
I am impressed by how good and even they sound when I am walking around.
I am impressed by how good and even they sound when I am walking around.
DCR Bluetooth speaker with RS100's
I built a portable BT speaker using Dayton RS100-4's in a dual chamber reflex box. The box was tuned for extension down to 60Hz. Works very nicely with an 8 watt Sure TPA3110D2 amp and a PE BT module.
More info here:
http://www.diyaudio.com/forums/multi-way/267585-project-big-bluetooth-spkr.html#post4176790
I built a portable BT speaker using Dayton RS100-4's in a dual chamber reflex box. The box was tuned for extension down to 60Hz. Works very nicely with an 8 watt Sure TPA3110D2 amp and a PE BT module.
More info here:
http://www.diyaudio.com/forums/multi-way/267585-project-big-bluetooth-spkr.html#post4176790
OK - I'm going to have to do some reading in this thread. I'll be working from a temporary office for several months, and was trying to decide what I can do, (on the cheap) to have halfway decent sound - without building something elaborate.
I have a couple of Dayton Audio RS75-4's laying around, looking for something to do, Those, with a cheapo class D might fit the bill perfectly. 😀
I have a couple of Dayton Audio RS75-4's laying around, looking for something to do, Those, with a cheapo class D might fit the bill perfectly. 😀
Try building the mini Karlsonators 0.4x scale with your RS75's. That is an easy, fast project that sounds great.
Thanks for the suggestion. Time to use my Google-foo. I'll post back if i make something presentable, (that doesn't look like a grade school art project)😀
I can almost feel the hot glue burns on my fingers already. 😉
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Here is link to 0.4x K'nator.
http://www.diyaudio.com/forums/full-range/239338-mini-karlsonator-0-53x-dual-tc9fds-56.html#post3880182
Hot glue burns are a badge of manliness. 🙂
X
Did you or anybody else look at how a CLD foamcore box stacks up to panel damping as discussed in various BBC papers?
http://downloads.bbc.co.uk/rd/pubs/reports/1977-03.pdf
Did you or anybody else look at how a CLD foamcore box stacks up to panel damping as discussed in various BBC papers?
http://downloads.bbc.co.uk/rd/pubs/reports/1977-03.pdf
Pnix,
Thanks for the link to the paper - I have not seen it before so can't comment on comparison to BBC results. However, I have found that a CLD formed using two layers of foam core sandwiched with a thick layer of latex caulking compound dramatically reduces harmonic distortion in a foam core horn. It also increased the absolute SPL level because less of it went into vibrating the structure.
More info here:
http://www.diyaudio.com/forums/full-range/259293-prv-5mr450-ndy-fast-applications-13.html#post4036324
Without CLD:
After CLD applied:
What was neat was that I was playing music through the horn as I was applying the CLD panels and could hear it transform in front of my ears. Very cool and definitely something to be aware of as a tool to extract the most performance from a speaker. It may not be as dramatic with a box, but a horn, it makes all the difference.