Here I go at last!
Why bother with another project? Don't I have enough with so many unfinished projects already?
The answered is that I expect great things from this one: a front/rear horn loaded FR has a certain "magic" that is hard to resist.
If you don't want a big enclosure, don't read further...
It all began with the Autograph enclosure...a corner speaker. But I wanted a full frequency speaker that didn't need a corner to sound good, as not all rooms can accept those monsters.
After the 2:3 reduced Autograph replica (with AN super10 driver) defeated easilly my former Tannoy Definition 500 (I sold them), I began, with scottmoose's and AndrewT's invaluable help to develop the design that now occupies us.
The rear Autograph horn evolved to a very long horn, with a center block composed by 3 vertical foldings which then divide into two lateral blocks that flank the center block and which progresses front-back-front on the horizontal plane, to end on a big mouth " á la Kleinhorn" , but, as I said, divided in two.
The front horn is a reduced replica of Autograph's front horn.
I made a quick and dirthy version, halas, with a no-brand 3.5" midrange (not a true fulrange), that nevertheless sounds very good. HF lacks extension, midrange is beautifull, bass is wide and has surprising extension for such a little driver...bass is not very defined though, maybe because of the driver itself, maybe because of the long horn...I should buy a good 3.5" FR, but prefer to go straight to the developed version with a bigger one.
As you may know, soundstage is Wide and deep and instruments are very well placed and discrete.
I know it looks horrible (an uncompleted) , but believe me it sounds good.
The view from above should look like this:
This one explains how the wave goes (concentrate and you'll succeed ) . The enclosure front is 90cm *90cm.
Well, here I must seek help from The Wise to tune and fine-tune the enclosures to a decent frequency response, as I can't predict the behaviour of this enclosure with different FR drivers. As this enclosures can easilly be expanded to receive bigger drivers or even better a given enclosure could receive a bigger driver than it was intended, making a little mod and using a front horn suitable for its size
I am thinking a good 6.5 incher could do well. Or a 10incher on an 8" enclosure.
I am drawing detailed diagrams with autoCAD, which should be readable and modifiable by experts like you...
The only problem is that I don't know how to share these autoCAD files on a easy way.
Using autoCAD should allow for easy expansion and modification of the model, at your will, as it will facilitate the modeling for frequency response prediction.
We can discuss the pros and cons of this idea. Believe me, it is very easy to build!
Bare in mind that this was just a "first shot" model designed with pencil and paper only, as The Good Lord led me understand
I hope you like and feel inclined to cooperate.
These could be your last speakers
Bye,
M
Ooops ! I forgot the lateral view which should look like this
Why bother with another project? Don't I have enough with so many unfinished projects already?
The answered is that I expect great things from this one: a front/rear horn loaded FR has a certain "magic" that is hard to resist.
If you don't want a big enclosure, don't read further...
It all began with the Autograph enclosure...a corner speaker. But I wanted a full frequency speaker that didn't need a corner to sound good, as not all rooms can accept those monsters.
After the 2:3 reduced Autograph replica (with AN super10 driver) defeated easilly my former Tannoy Definition 500 (I sold them), I began, with scottmoose's and AndrewT's invaluable help to develop the design that now occupies us.
The rear Autograph horn evolved to a very long horn, with a center block composed by 3 vertical foldings which then divide into two lateral blocks that flank the center block and which progresses front-back-front on the horizontal plane, to end on a big mouth " á la Kleinhorn" , but, as I said, divided in two.
The front horn is a reduced replica of Autograph's front horn.
I made a quick and dirthy version, halas, with a no-brand 3.5" midrange (not a true fulrange), that nevertheless sounds very good. HF lacks extension, midrange is beautifull, bass is wide and has surprising extension for such a little driver...bass is not very defined though, maybe because of the driver itself, maybe because of the long horn...I should buy a good 3.5" FR, but prefer to go straight to the developed version with a bigger one.
As you may know, soundstage is Wide and deep and instruments are very well placed and discrete.
I know it looks horrible (an uncompleted) , but believe me it sounds good.
The view from above should look like this:
This one explains how the wave goes (concentrate and you'll succeed
) . The enclosure front is 90cm *90cm.
Well, here I must seek help from The Wise to tune and fine-tune the enclosures to a decent frequency response, as I can't predict the behaviour of this enclosure with different FR drivers. As this enclosures can easilly be expanded to receive bigger drivers or even better a given enclosure could receive a bigger driver than it was intended, making a little mod and using a front horn suitable for its size
I am thinking a good 6.5 incher could do well. Or a 10incher on an 8" enclosure.
I am drawing detailed diagrams with autoCAD, which should be readable and modifiable by experts like you...
The only problem is that I don't know how to share these autoCAD files on a easy way.
Using autoCAD should allow for easy expansion and modification of the model, at your will, as it will facilitate the modeling for frequency response prediction.
We can discuss the pros and cons of this idea. Believe me, it is very easy to build!
Bare in mind that this was just a "first shot" model designed with pencil and paper only, as The Good Lord led me understand
I hope you like and feel inclined to cooperate.
These could be your last speakers
Bye,
M
Ooops ! I forgot the lateral view which should look like this
More thoughts. Based on my experience.
1) as I said many times before, the climbing frequency response of most FR is well matched to the frequency enhancement patern of a front and rear horn enclosure, so, with a little tweaking of the box we can avoid any corrective circuit and end with a respectable curve with only one driver.
2) having horns for mid and low should sound better than only having horn for low or for mid. The horn acts as an acoustic amplifier, this enhances the driver's sensitivity, and makes feel the music as if you were using a magnifying lens; the music "jumps" to you, with great dynamic contrasts. This is lost for the part of the spectrum not using a horn, which could cause lack of coherence.
3) If you have a preferred 3.5"-4.5" FR you could use this enclosure but the driver will be too low. As I said, the enclosure can be easilly modded to make almost any combination, including putting the driver higher. This will lenghten the rear horn a bit.
4) There is enough room to make a bigger "compression chamber" if one feels the need for it, based on, I hope, future simulations.
Can anyone recommend an easy way to share the autoCAD files for you to analize the project?
Will google-documents be good?
Thanks
M
1) as I said many times before, the climbing frequency response of most FR is well matched to the frequency enhancement patern of a front and rear horn enclosure, so, with a little tweaking of the box we can avoid any corrective circuit and end with a respectable curve with only one driver.
2) having horns for mid and low should sound better than only having horn for low or for mid. The horn acts as an acoustic amplifier, this enhances the driver's sensitivity, and makes feel the music as if you were using a magnifying lens; the music "jumps" to you, with great dynamic contrasts. This is lost for the part of the spectrum not using a horn, which could cause lack of coherence.
3) If you have a preferred 3.5"-4.5" FR you could use this enclosure but the driver will be too low. As I said, the enclosure can be easilly modded to make almost any combination, including putting the driver higher. This will lenghten the rear horn a bit.
4) There is enough room to make a bigger "compression chamber" if one feels the need for it, based on, I hope, future simulations.
Can anyone recommend an easy way to share the autoCAD files for you to analize the project?
Will google-documents be good?
Thanks
M
>>> My first front and rear horn loaded fullrange design…
For your first front and rear horn, why did you decide upon such a simple design?
Actually, its probably a good idea to combine both front and rear loading. But I would look for a more elegant way to do it. I am curious to see how your project shapes up.
For your first front and rear horn, why did you decide upon such a simple design?
Actually, its probably a good idea to combine both front and rear loading. But I would look for a more elegant way to do it. I am curious to see how your project shapes up.
Hi Godzilla,
By elegant do you mean good looking?
I only want real fullrange extension without a SW.
From what I'm hearing today (I swaped DACs) it is totally doable.
Hi Britbug ,
Sorry, MJK?
Edit: OK, I got it
I will succeed at the end, trust me. I hope some of The Wise come around and help a little to shorten the "time to marketing"
I really find building square boxes too boring
(people seem to like building square boxes, strange, isn't it?)
Anyway, this enclosure can be made of 6mm MDF for the 3.5-4.5incher, as there is plenty of space to put reinforcements. I used spare plywood (9mm) from other projects for the side panel, with external reinforcement: very cheap.
I also consider, given the size of, say, an 8" version, to build blocks that could be assembled/disassembled with bolts.
Did you notice that bass and midrange/HF have a "coaxial" patern of emision? I chose a 90º angle for the bass horn mouth to match the front horn's firing angle
When you walk around the room you always have at least two "half-mouths" facing you: the soundstage never disapears and the "sweetspot" is not a spot but big area.
Ample soundstage + depth of image + great voices + dynamics= opera (sorry)
Glad that you replied, guys.
Cheers,
M
By elegant do you mean good looking?
I only want real fullrange extension without a SW.
From what I'm hearing today (I swaped DACs) it is totally doable.
Hi Britbug ,
Sorry, MJK?
Edit: OK, I got it
I will succeed at the end, trust me. I hope some of The Wise come around and help a little to shorten the "time to marketing"
I really find building square boxes too boring
(people seem to like building square boxes, strange, isn't it?)
Anyway, this enclosure can be made of 6mm MDF for the 3.5-4.5incher, as there is plenty of space to put reinforcements. I used spare plywood (9mm) from other projects for the side panel, with external reinforcement: very cheap.
I also consider, given the size of, say, an 8" version, to build blocks that could be assembled/disassembled with bolts.
Did you notice that bass and midrange/HF have a "coaxial" patern of emision? I chose a 90º angle for the bass horn mouth to match the front horn's firing angle
When you walk around the room you always have at least two "half-mouths" facing you: the soundstage never disapears and the "sweetspot" is not a spot but big area.
Ample soundstage + depth of image + great voices + dynamics= opera (sorry)
Glad that you replied, guys.
Cheers,
M
Hi again,
In fact I only want to simulate the rear horn response, because I fear having TOO MUCH BASS. The behavior of the front horn is familiar to me. I also want to simulate how much midbass is enhanced.
I think that different driver sizes will need perhaps different rear horn design.
I think a good start will be a 6.5" driver and its corresponding enclosure. Smaller drivers' resonance is higher and that would make a dirty midbass response, I guess
For example, I hear that some midbass notes "shout" at me with my little driver and low bass notes are clean.
Have you heard a piano through a front/rear horn loaded FR??? (Kleinhorn-like, that is)
Response (attack) is fast; maybe a little delayed in my long horn, but that increases the sens of recording hall volume
As the mouth of the rear horn is big, the apparent sound source for bass frequencies of large bass instruments is also large. That, added to the natural bass harmonics and room reverberations, makes a lovely experience.
Silly me, I discovered that it was much easier to share diagrams than I thought. If anyone wants the original autoCAD files just send an email.
This is the center block; left is front. Follow the labyrinth and you will see that it "ends" on the left inferior corner, which in reality ends with two windows that feed each one the lateral foldings blocks, that are shown on the next diagram...
As my skills with CAD are minimal, I did not draw the width of the wood used.
You will have to consider it, of course, if you'd like to play with the boxes.
If you want to use a driver of 6.5", just multiply each dimension by 6.5/4 (the present enclosure accepts 3.5"-4.5" drivers). Dimensions can be modified as your imagination allows.
Edit: oops! The diagrams are too small! I will change them tomorrow. Sorry.
In fact I only want to simulate the rear horn response, because I fear having TOO MUCH BASS. The behavior of the front horn is familiar to me. I also want to simulate how much midbass is enhanced.
I think that different driver sizes will need perhaps different rear horn design.
I think a good start will be a 6.5" driver and its corresponding enclosure. Smaller drivers' resonance is higher and that would make a dirty midbass response, I guess
For example, I hear that some midbass notes "shout" at me with my little driver and low bass notes are clean.
Have you heard a piano through a front/rear horn loaded FR??? (Kleinhorn-like, that is)
Response (attack) is fast; maybe a little delayed in my long horn, but that increases the sens of recording hall volume
As the mouth of the rear horn is big, the apparent sound source for bass frequencies of large bass instruments is also large. That, added to the natural bass harmonics and room reverberations, makes a lovely experience.
Silly me, I discovered that it was much easier to share diagrams than I thought. If anyone wants the original autoCAD files just send an email.
This is the center block; left is front. Follow the labyrinth and you will see that it "ends" on the left inferior corner, which in reality ends with two windows that feed each one the lateral foldings blocks, that are shown on the next diagram...
As my skills with CAD are minimal, I did not draw the width of the wood used.
You will have to consider it, of course, if you'd like to play with the boxes.
If you want to use a driver of 6.5", just multiply each dimension by 6.5/4 (the present enclosure accepts 3.5"-4.5" drivers). Dimensions can be modified as your imagination allows.
Edit: oops! The diagrams are too small! I will change them tomorrow. Sorry.
"For example, I hear that some midbass notes "shout" at me with my little driver and low bass notes are clean."
Max, I certainly will not put myself in the wise group, but I have learned a few things about prototyping in the last couple of years. I wish you well on your project. It looks interesting. To comment on your quote above, have you fully braced and secured the cabinet, making it as solid as you would on a final build? Without doing that, you will never know whether a "shout" or honk, etc., is in the design or something with the cabinet itself.
Doug
Max, I certainly will not put myself in the wise group, but I have learned a few things about prototyping in the last couple of years. I wish you well on your project. It looks interesting. To comment on your quote above, have you fully braced and secured the cabinet, making it as solid as you would on a final build? Without doing that, you will never know whether a "shout" or honk, etc., is in the design or something with the cabinet itself.
Doug
Hi Doug
Thanks for your comment. Yes, I think I have put enough reinforcement. The first lateral folding run parallel walls so it is easy to use spare cut wood to glue it and make a stiff enclosure.
I re-read some of Scottmoose's comments on my other thread... http://www.diyaudio.com/forums/showthread.php?threadid=86221&perpage=25&highlight=&pagenumber=3
...and I think I will increase a lot the compression chamber of this enclosure to avoid midbass contamination. (I think he has not shown here because he knows I did not make my homework = studying the theory ).
Cheers,
M
Thanks for your comment. Yes, I think I have put enough reinforcement. The first lateral folding run parallel walls so it is easy to use spare cut wood to glue it and make a stiff enclosure.
I re-read some of Scottmoose's comments on my other thread... http://www.diyaudio.com/forums/showthread.php?threadid=86221&perpage=25&highlight=&pagenumber=3
...and I think I will increase a lot the compression chamber of this enclosure to avoid midbass contamination. (I think he has not shown here because he knows I did not make my homework = studying the theory
).Cheers,
M
I deleted my previous images because they were too small.
These should be good.
Central block. Remember, these are good for little FR, like 3.5" to 4.5". You can "expand" or mod the enclosure as you wish.
Lateral panels that flank the central block. First folding goes from front to rear and second one the oposite way.
A view from the ceiling should look like this. I tried to mark potential compression chamber area. I also marked other front horn size for bigger drivers
Frontal aspect.
This is only a concept, but you get the idea...
These should be good.
Central block. Remember, these are good for little FR, like 3.5" to 4.5". You can "expand" or mod the enclosure as you wish.
Lateral panels that flank the central block. First folding goes from front to rear and second one the oposite way.
A view from the ceiling should look like this. I tried to mark potential compression chamber area. I also marked other front horn size for bigger drivers
Frontal aspect.
This is only a concept, but you get the idea...
I haven't shown here before Max because I'm a bit innundated at the moment.
Anyway, adjusting the filter chamber size will adjust the upper cut-off point of the back-horn, although we need to take the driver's mass-corner into account & also balance pressures with the front horn too. You might find it worth reading Leach's paper on horn design, although it's worth keeping in mind that Leach went all-out for maximum efficiency / gain and not everyone approves of that. As it happens I do: you can always damp down what you've got too much of; it's a bit trickier to boost what you don't have in the first place. http://users.ece.gatech.edu/~mleach/papers/HornPaper/HornPaper.pdf
If you want me to model the back-horn response, I'll do it when I get a spare moment. I'll need the volume of the back-chamber (preferably it's length, width & height, though I can fudge it if necessary) the location of the driver in the chamber (far end of the chamber from the throat, same end as the throat, or some point between them), the throat CSA, the mouth CSA, pathlength and type of flare used. If you haven't stuck to a mathematical expansion, I can do that too; just give me the CSA of the horn at different points along it's length. I'd suggest at each bend.
Anyway, adjusting the filter chamber size will adjust the upper cut-off point of the back-horn, although we need to take the driver's mass-corner into account & also balance pressures with the front horn too. You might find it worth reading Leach's paper on horn design, although it's worth keeping in mind that Leach went all-out for maximum efficiency / gain and not everyone approves of that. As it happens I do: you can always damp down what you've got too much of; it's a bit trickier to boost what you don't have in the first place. http://users.ece.gatech.edu/~mleach/papers/HornPaper/HornPaper.pdf
If you want me to model the back-horn response, I'll do it when I get a spare moment. I'll need the volume of the back-chamber (preferably it's length, width & height, though I can fudge it if necessary) the location of the driver in the chamber (far end of the chamber from the throat, same end as the throat, or some point between them), the throat CSA, the mouth CSA, pathlength and type of flare used. If you haven't stuck to a mathematical expansion, I can do that too; just give me the CSA of the horn at different points along it's length. I'd suggest at each bend.
Hi Scottmoose
What? Do you mean physically innundated? I hope not.
Don't worry, I am also almost exhausted with my many jobs and many projects, so I'll go slowly with this one.
Believe me, this enclosure promises...
I will draw the back horn unfolded. This will make things clearer and will permit an easier calculation of the CSA's.
I plan to design also the bigger prototype, wich in fact is my main goal.
I share your view about damping abundance...
Efficiency...I don't know if it is maximal but surelly you could use a flyweight amp with them.
It should be easy to accomodate the size and form of the horn for a better behavior. I think of it as a flexible design. It is not apparent from the drawings but once you begin the built you realize how flexible it could be.
Thanks for your kind offer.
Good luck.
M
What? Do you mean physically innundated? I hope not.
Don't worry, I am also almost exhausted with my many jobs and many projects, so I'll go slowly with this one.
Believe me, this enclosure promises...
I will draw the back horn unfolded. This will make things clearer and will permit an easier calculation of the CSA's.
I plan to design also the bigger prototype, wich in fact is my main goal.
I share your view about damping abundance...
Efficiency...I don't know if it is maximal but surelly you could use a flyweight amp with them.
It should be easy to accomodate the size and form of the horn for a better behavior. I think of it as a flexible design. It is not apparent from the drawings but once you begin the built you realize how flexible it could be.
Thanks for your kind offer.
Good luck.
M
Thanks Scottmoose for the paper. It'll take me 2 or 3 years to digest it
I'm having troubles to export the diagrams from AutoCAD to jpg or other...
I copied the best I could on Paint. As per your previous guidelines (the other thread) I made a long horn with almost no expansion at first and then a final expansion to the mouth. Maybe I exaggerated things here It looks like those horns that the Lama's use for their celebrations 
I feel that the throat is not wide enough: 10.5cm * 12cm
I expanded the compression chamber to: 24*24*12cm
The mouth is : 90*66cm
Anyway, I am considering a speaker with a good 4.5", so nice is the music I'm getting...if it weren't for the stress at loud passages...
The driver barely moves but I am used to "bigger is better"
So, during tea time, I played with variations of the theme, focused on the weaknesses of my present enclosure: in this version the driver is placed at a higher level and compression chamber can be increased in size at will. It also allows for a wider throat. The length of the rear horn is shorter with a faster expansion...but the enclosure can be taller and the mouth can even be increased in height.
In black is the modded center block. Red line is the music flow. In green is the first lateral folding. In orange is the final lateral folding. Sorry for the intricate and bad drawing.
From front it should look like this:
Cheers,
M
Trying to figure it out...
I'm having troubles to export the diagrams from AutoCAD to jpg or other...
I copied the best I could on Paint. As per your previous guidelines (the other thread) I made a long horn with almost no expansion at first and then a final expansion to the mouth. Maybe I exaggerated things here
It looks like those horns that the Lama's use for their celebrations I feel that the throat is not wide enough: 10.5cm * 12cm
I expanded the compression chamber to: 24*24*12cm
The mouth is : 90*66cm
Anyway, I am considering a speaker with a good 4.5", so nice is the music I'm getting...if it weren't for the stress at loud passages...
The driver barely moves but I am used to "bigger is better"
So, during tea time, I played with variations of the theme, focused on the weaknesses of my present enclosure: in this version the driver is placed at a higher level and compression chamber can be increased in size at will. It also allows for a wider throat. The length of the rear horn is shorter with a faster expansion...but the enclosure can be taller and the mouth can even be increased in height.
In black is the modded center block. Red line is the music flow. In green is the first lateral folding. In orange is the final lateral folding. Sorry for the intricate and bad drawing.
From front it should look like this:
Cheers,
M
Trying to figure it out...
OK, when I get some free time I'll see what it looks like. What driver are you using?
Leach's paper is not the most readable if you're not into the old mathematics. Much easier to follow (& a pleasent read in its own right) is Dinsdale's article, which you'll find here: http://www.volvotreter.de/dl-section.htm scroll to the bottom of the page & you'll see the 3 pdf files.
Leach's paper is not the most readable if you're not into the old mathematics. Much easier to follow (& a pleasent read in its own right) is Dinsdale's article, which you'll find here: http://www.volvotreter.de/dl-section.htm scroll to the bottom of the page & you'll see the 3 pdf files.
Hi Scottmoose and Cloth Ears,
I will read your interesting links.
About the driver, as I said I'm using a no-name midrange now but I planned something like Fostex' FE126E 4.5" FULL RANGE.
What software do you use to predict response? Maybe I could use it and save your time (or confirm results)
(or is it too complicated?)
Cheers,
M
PS: yesterday I swaped to my modded Paradigm M3 big monitors; there's no way I could be happy with bass reflex systems anymore
I will read your interesting links.
About the driver, as I said I'm using a no-name midrange now but I planned something like Fostex' FE126E 4.5" FULL RANGE.
What software do you use to predict response? Maybe I could use it and save your time (or confirm results)
(or is it too complicated?)
Cheers,
M
PS: yesterday I swaped to my modded Paradigm M3 big monitors; there's no way I could be happy with bass reflex systems anymore
Martin King's MathCad worksheets. The annual charge is $25 for the complete set, which IMO is excellent value for money -especially as Martin periodically updates them, and you get all those updates included in the price. Hornresp. and AkaBak are very fine pieces of (free!) software, although the latter should be avoided at all costs if you don't like heavy math and equations, while the former is not quite as flexible in some ways as MathCad (although it offers a couple of features Martin's worksheets do not). I use all three, but MathCad dominates -about 98% of what I do is modelled in it. I cannot recommend it highly enough, and it's pretty easy to use too.
One thing to remember about all modelling software though: that's just what it is: modelling software. It won't design the enclosure for you, just allow you to look at what it does, and fine-tune it. The person driving it still needs to know how to design an enclosure, and also to know what the software tells you, and also what it doesn't tell you.
One thing to remember about all modelling software though: that's just what it is: modelling software. It won't design the enclosure for you, just allow you to look at what it does, and fine-tune it. The person driving it still needs to know how to design an enclosure, and also to know what the software tells you, and also what it doesn't tell you.
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