xrk971: I saw you have a kind of foam collectionwhich one do you prefer and why?
How does one pick a favorite child?
Depends on what you want them to do. They all have their place.
All around best is the mini Karlsonator.
Best hifi sound is Nautaloss with sub in a FAST.
Best simple to make for background music is flat wall MLTL.
Most cool is Cornu.
I forgot to mention the speaker I listen to the most is the one mounted in the bedroom on the wall: the flat BIB or FIB. It has enough bass, great overall balance and just about anything sounds good on it at moderate levels.
The throat is formed naturally by the two pieces which spiral outwards. You do not actually cut the throat opening. 3 inches is the axial spacing between the front and back panel. I would make it 2.5 inches as my simulation showed that was the best to balance the bass with the highs.
You might want to post questions in the Cornu thread - others may be able to answer there and your questions will help others trying to build it too.
http://www.diyaudio.com/forums/full-range/225622-ever-think-building-cornu-spiral-horn-now-you-can.html
Good luck.
X
You might want to post questions in the Cornu thread - others may be able to answer there and your questions will help others trying to build it too.
http://www.diyaudio.com/forums/full-range/225622-ever-think-building-cornu-spiral-horn-now-you-can.html
Good luck.
X
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The Simplest FC OB Speaker Ever
If you are lazy and want to make the easiest FC speaker ever and you have always wondered what an open baffle (OB) speaker sounds like you might want to try this...
Get qnty 4 of these exciters from PE for $3.50 ea x 4 = $14: HiWave 25mm SoundPax Exciter Turns Virtually Anything Into A | 309-149
Get 2 sheets of FC ($2)
Glue the exciters to the back of the FC panel (2 each, slightly off center so you are not on the fundamental drumhead vibrational mode.
Hook them up in parallel for a 4 ohm load and connect to a nice class D amp like the TPA3116D2 and you are in for some OB cheap thrills!
You have a 20 x 30 in OB that actually reaches 50 Hz and sounds kind of nice. It lacks the airiness of a top end and can use a piezo tweeter but over the range that it works it is amazingly even. Don't let the cheap price and small size fool you - it can put out some decent SPL. For best results hang by string suspended in mid air for a really nice OB sound that can fill the room.
Here are some measurements of the frequency response (near field at 12 in away) with impedance as seen by amp (pretty flat near 4 to 6 ohms), harmonic distortion, and impulse response.
Don't mind the little blocks of gray foam - I was going to wall mount them but they sound so much better away from a wall as an OB. The little FC frame around the edges is optional - I made it for wall mounting but that can be omitted too.
Have fun with it.
If you are lazy and want to make the easiest FC speaker ever and you have always wondered what an open baffle (OB) speaker sounds like you might want to try this...
Get qnty 4 of these exciters from PE for $3.50 ea x 4 = $14: HiWave 25mm SoundPax Exciter Turns Virtually Anything Into A | 309-149
Get 2 sheets of FC ($2)
Glue the exciters to the back of the FC panel (2 each, slightly off center so you are not on the fundamental drumhead vibrational mode.
Hook them up in parallel for a 4 ohm load and connect to a nice class D amp like the TPA3116D2 and you are in for some OB cheap thrills!
You have a 20 x 30 in OB that actually reaches 50 Hz and sounds kind of nice. It lacks the airiness of a top end and can use a piezo tweeter but over the range that it works it is amazingly even. Don't let the cheap price and small size fool you - it can put out some decent SPL. For best results hang by string suspended in mid air for a really nice OB sound that can fill the room.
Here are some measurements of the frequency response (near field at 12 in away) with impedance as seen by amp (pretty flat near 4 to 6 ohms), harmonic distortion, and impulse response.
Don't mind the little blocks of gray foam - I was going to wall mount them but they sound so much better away from a wall as an OB. The little FC frame around the edges is optional - I made it for wall mounting but that can be omitted too.
Have fun with it.
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Well,
Thank you xrk971, it is interesting...
Basically, I am not looking for the simplest speaker
I don't know full range driver and I would like to have a 'cheap' test .
I like jazz with good bass.
My second motivation is for my wife, she is Yoga teacher and would like a good but simple portable audio system, with a nice design.
I would like to build it by myself, I ordered a 3116 amp, and thinking on speakers...
I had a look on your Tear Drop foam speakers. I really like the design (good job). It may be a good option, but it is too big. I need something small, let say 8' long.... So I need to think a little bit about that.
Thank you xrk971, it is interesting...
Basically, I am not looking for the simplest speaker
I don't know full range driver and I would like to have a 'cheap' test .
I like jazz with good bass.
My second motivation is for my wife, she is Yoga teacher and would like a good but simple portable audio system, with a nice design.
I would like to build it by myself, I ordered a 3116 amp, and thinking on speakers...
I had a look on your Tear Drop foam speakers. I really like the design (good job). It may be a good option, but it is too big. I need something small, let say 8' long.... So I need to think a little bit about that.
From what you describe the 0.4x Karlsonator will work well for your wife. It is compact and portable and sounds very nice for yoga lessons.
Prezden,
I am far from being a master at anything I think Grandcalmar is probably the current FC master.
Are you talking about this speaker?
If you are then check out the Nautaloss thread: http://www.diyaudio.com/forums/full-range/247598-nautaloss-ref-monitor.html
This is by far the best sounding FC speaker I have built. It is probably hifi studio reference quality. It is a FAST 2-way system though using active bi-amping and a DSP for crossover. Not expensive given that the drivers cost under $70 (8 total) and the miniDSP is $90, and you probably have enough TPA31xx amps to serve as the bi-amps.
The speaker is a super easy build. If you build the Nautaloss sub that is more challenging due to sheer size (full sheet of FC per side panel). Lots of fun and it sounds great.
Here is the quad driver sub (you see 2 but those are face-to-face mounted in push-pull):
This is the performance this system can achieve (yes, that is -50 dB total harmonic distortion above 200 Hz):
And here is the polar response of the full range Vifa Nautaloss II tops from 0 deg to 90 deg - pretty good for any driver at any price:
I am far from being a master at anything
I think Grandcalmar is probably the current FC master.Are you talking about this speaker?
If you are then check out the Nautaloss thread: http://www.diyaudio.com/forums/full-range/247598-nautaloss-ref-monitor.html
This is by far the best sounding FC speaker I have built. It is probably hifi studio reference quality. It is a FAST 2-way system though using active bi-amping and a DSP for crossover. Not expensive given that the drivers cost under $70 (8 total) and the miniDSP is $90, and you probably have enough TPA31xx amps to serve as the bi-amps.
The speaker is a super easy build. If you build the Nautaloss sub that is more challenging due to sheer size (full sheet of FC per side panel). Lots of fun and it sounds great.
Here is the quad driver sub (you see 2 but those are face-to-face mounted in push-pull):
This is the performance this system can achieve (yes, that is -50 dB total harmonic distortion above 200 Hz):
And here is the polar response of the full range Vifa Nautaloss II tops from 0 deg to 90 deg - pretty good for any driver at any price:
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Dual Chamber Reflex Bookshelf Speaker
After seeing how Grandcalmar was able to use a single sheet of FC and bend it at corners to reduce the joints that were needed, I thought why not use a single sheet of FC and wrap it around a rounded corner baffle to get a smooth seamless effect? Oh, and while I am at it, why even make a rectangular prism anymore? Curves are FC's friend! I really like the profile of Wesayso's tower and basically wanted a similar shape but smaller for a single driver. I also have never made a dual chamber reflex (DCR) before so I thought I would combine that into this build too. The speaker is about 6 in wide x 14 in high x 11 in deep and uses a single Vifa TC9FD. The slot vents are 4.0 in x 0.5 in x 4.7 in long. The fabrication method was very different from my previous builds and is closest to building a curved front horn. Once you figure it out, the method is very efficient as there are 5 parts to the structure including the internal separator wall. It was built completely with hot melt glue so it went together fast. I think aesthetically, this is one the prettier speakers I have made. The Akabak model shows that having such a svelte front cross section really requires baffle step compensation. I need to get parts for BSC circuit as I want this to be a simple to use speaker that I can move about with just a small class D amp. For now, I am using it EQ'd and it sounds very nice - still mono but very clear and I am quite sure the soundstage in stereo will perhaps be one of the best I have heard of all my speakers. The clarity is very good and I think the curved edges on the baffle make a difference! Definitely a keeper though and justifies building the stereo pair at this point.
After seeing how Grandcalmar was able to use a single sheet of FC and bend it at corners to reduce the joints that were needed, I thought why not use a single sheet of FC and wrap it around a rounded corner baffle to get a smooth seamless effect? Oh, and while I am at it, why even make a rectangular prism anymore? Curves are FC's friend! I really like the profile of Wesayso's tower and basically wanted a similar shape but smaller for a single driver. I also have never made a dual chamber reflex (DCR) before so I thought I would combine that into this build too. The speaker is about 6 in wide x 14 in high x 11 in deep and uses a single Vifa TC9FD. The slot vents are 4.0 in x 0.5 in x 4.7 in long. The fabrication method was very different from my previous builds and is closest to building a curved front horn. Once you figure it out, the method is very efficient as there are 5 parts to the structure including the internal separator wall. It was built completely with hot melt glue so it went together fast. I think aesthetically, this is one the prettier speakers I have made. The Akabak model shows that having such a svelte front cross section really requires baffle step compensation. I need to get parts for BSC circuit as I want this to be a simple to use speaker that I can move about with just a small class D amp. For now, I am using it EQ'd and it sounds very nice - still mono but very clear and I am quite sure the soundstage in stereo will perhaps be one of the best I have heard of all my speakers. The clarity is very good and I think the curved edges on the baffle make a difference! Definitely a keeper though and justifies building the stereo pair at this point.
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Total volume is 755 cubic inch, upper chamber is 2/3 vol and lower is 1/3 vol. Ports are 2 square in CSA slots as described and vent between chambers is 2 square in CSA but 1.5 in long. Tuned to 50 Hz.
Sure you can do dual drivers but that will make cabinet get bigger. Dipole or bipole will not work in this particular cabinet as tail is tapered. However a rectangular prism box would work.
Sure you can do dual drivers but that will make cabinet get bigger. Dipole or bipole will not work in this particular cabinet as tail is tapered. However a rectangular prism box would work.
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