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Angelo888
26-05-2008, 21:44
hi

my name is Angelo. I am swiss/italian, but live for more than 10 Years in brazil. Two years ago i started to dedicate myself more to Audio, and last year i started to design and build hornspeakers, and horns, made of MDF. To make these, i built a big wood lathe. With it i can turn horns up to one meter diameter.

here a link to my foto blog :

http://www.flickr.com/photos/12312992@N07/page1/

at the moment i am finishing to build for myself a 4way full frontloaded hornsystem, that can be seen also on my blog. My intend is to make my realisations also available for others,the horns, and also complete hornspeaker systems. For this purpose, i am working on a homepage. a forum, dedicated exclusively to horns, is up for one week now. I invite you to visit it and participate :

http://www.audiovoice-acoustics.com/forum/

Angelo

Jay
27-05-2008, 00:37
Beautiful workmanship on those. I have always dreamed of being able to "turn" an MDF horn. The closet I've come is my home built 7 foot folded bass horns, with the 15" driver acting as a direct radiator.

Kurt-Holz
27-05-2008, 01:29
Hi Angelo

those really are very nice looking, you put a lot of work into those,you should do well, keep us up to date on your work

regards

Kurt

BajaGringo
27-05-2008, 01:39
Just one word - WOW!!!

Filterlab
27-05-2008, 10:32
Two words; WOW WOW!

Excellent work Angelo, excellent indeed!

Filterlab
27-05-2008, 11:23
Love those ones:

http://farm2.static.flickr.com/1396/1408285284_25fba8fe3d.jpg?v=0

Filterlab
27-05-2008, 11:26
Pete (i_should_coco) will definitely love these puppies:

http://farm3.static.flickr.com/2152/2049741761_e171593517_o.jpg

Marco
27-05-2008, 12:44
If he ever decides to post here (he has registered but just seems to want to lurk)... :(

I don't know what his problem is because he's not exactly 'shy' on Wigwam :confused:

Marco.

Angelo888
27-05-2008, 15:52
hi Marco, hi all

no problem to post here. However, what should i respond to WOW !!, or similar comments like those ? Of course i apprechiate all positive compliments, but hard to respond on that. Please make specific questions , and i will be pleased to answer and share here. That's why i registered.

Angelo

Angelo888
27-05-2008, 16:03
Love those ones:

http://farm2.static.flickr.com/1396/1408285284_25fba8fe3d.jpg?v=0

Those cab's took more than 5 month , and over 250h of work, to be built. That's why i think i will hardly make a second pair for commerce. Too much work on these. The horns are Orpheans from BD-design. They have been replaced with own horns, made with MDF, and using a Radian 950pb compression driver, from 300hz up. Crossing is too low, the horn should be bigger than 20", to reproduce the lower midrange frequencies with best results. It sounds much better with the 25" horns. On them, lower midrange was absolutely wonderful,, speed, dynamics and soundstage are simply breath taking. The best i got so far. These speakers will be replaced soon with the big 4way frontloaded horn system, which is beeing built right now. It is taking also a LOT of work to make it, too. Almost 3 month working on this system, and it will be finished probably in about one month, or so.

Angelo

Angelo888
18-06-2008, 17:55
hi

today my first midbass horn got ready. It is painted with poliurethan PU, black satin , which leaves a raw surface.

mouth size is 38" / 96cm diameter, and thorat 4" /10cm.

Weight is approximately 130kg.

Fc is 145hz, and 125hz at half space.

I will use it between 150hz and 700hz, with Fane Studio 8M driver,
in my next hornspeaker system, full frontloaded, 4 way.


Angelo

http://i307.photobucket.com/albums/nn281/AudioVoice/Imagem277.jpg

http://i307.photobucket.com/albums/nn281/AudioVoice/Imagem292.jpg

http://i307.photobucket.com/albums/nn281/AudioVoice/Imagem281.jpg

more pictures at Audio Voice Acoustics forum :

http://www.audiovoice-acoustics.com/forum/showthread.php?t=227

nafanja
26-02-2009, 16:19
Tell me please.\

Do you make the tweeters with sencitivity near 96 db and frequency near 18-20 kHz?

Angelo888
27-02-2009, 14:01
hello Nafanja

sensitivity and power response depends more of the driver used. A horn gives usually a gain of 3 - 6db, while it functions as a acoustic high and lowpass filter. In the 18 - 20khz region, a horn has no function anymore, the wavelength are too short.

Angelo

Angelo888
04-04-2009, 01:34
hi all

some time since i posted last time at this forum.

here my finished system. I don't think there is more room for improvement, after some tweaks in the last few month - i am very satisfied with the result now.

here the thread at my forum with full description of the system:

http://www.audiovoice-acoustics.com/forum/showthread.php?t=405

http://i307.photobucket.com/albums/nn281/AudioVoice/Som3.jpg

http://i307.photobucket.com/albums/nn281/AudioVoice/Som4.jpg

Cobra2
28-04-2009, 09:14
WOW!!!

Arne K

Angelo888
26-08-2009, 00:47
hi all

a few month ago i got a deal at ebay, and took the chance to buy and try a pair of Vitavox AK154 woofers. They were at pretty bad shape, so i restaured and refurbished the cones. I replaced a pair of Beyma 15" LX60's woofers with it. The difference is quit remarkable. I wrote some comments at my forum :

http://www.audiovoice-acoustics.com/forum/showthread.php?t=195&page=3

Angelo

Spectral Morn
26-08-2009, 08:55
hi all

some time since i posted last time at this forum.

here my finished system. I don't think there is more room for improvement, after some tweaks in the last few month - i am very satisfied with the result now.

here the thread at my forum with full description of the system:

http://www.audiovoice-acoustics.com/forum/showthread.php?t=405

http://i307.photobucket.com/albums/nn281/AudioVoice/Som3.jpg

http://i307.photobucket.com/albums/nn281/AudioVoice/Som4.jpg

I'll second that wow and raise you with a WOW!!!!!

Thats a lot of speakers, how does it sound ?


Regards D S D L

Angelo888
26-08-2009, 13:28
best to let talk someone else than me, that heard my system :

see the last post :

http://www.audiovoice-acoustics.com/forum/showthread.php?t=650

and :

http://www.audiovoice-acoustics.com/forum/showthread.php?p=2479#post2479

translated :

Sunday, the 23 of August , i and fellow Edison Freire had the opportunity to meet in the city of Aracaju, Mr. Angelo and his system.
Consisting of a beautiful amplifier SE, Italian, and a set of Loudspeaker based Horns and Sub woofers.
I confess that I was very impressed with the refinement of the construction of the speaker system . All MDF, it has a finish worthy of the best Italian lutiers, which demonstrates that its builder, Angelo himself, brings into the vein, the art of the great Italian designers of all time.
The sound is an impressive naturalness and an incredible sensitivity.
I think it is right of every audiophile one day be able to see and hear such a system.

Isaac Sandes

Angelo888
21-10-2011, 02:48
hi guys

its a couple of years, i don't post at this forum. Here a update of my system:
I replaced Coral H104 tweeter with Beyma TPL-150 Air Motion Transformer mid/tweeter , with a wave guide made by my own.

Here how the system looks like today :

http://i893.photobucket.com/albums/ac134/audiovoice1/012-2.jpg

this is the inroom frequency response graph, measured at 1m distance from the speakers:

http://i893.photobucket.com/albums/ac134/audiovoice1/sistematodocomS2.jpg

more pictures and descriptions, at my forum :

http://www.audiovoice-acoustics.com/forum/showthread.php?p=5136#post5136

Angelo

Magna Audio
21-10-2011, 09:57
Look great.
I was toying with the idea of a big wood lathe but went down the conical path (for the time being at least...) The upper mid I build was so good I thought I'd apply it to all horns and see.
Are you considering a tapped horn? I have found they integrated well once sorted (I originally had crossover and Zobel issues) they work really well doing nice deep bass support on normal stuff and where there is sub bass you hear that too. They are fast too not ponderous booming away.

What frequencies are you crossing at? What efficiencies do you have / measure?
Do you find that sound coming off the tweeter hitting the backs of the other horns and interfering a bit to be a problem? I experimented with acoustic absorption there and found it beneficial. Cleans the already pure horn sound up a little further. 5 way really is the way to go I think.

Do you have one amp and L-pads? I still use passive crossovers but use 5 amps, one per channel and level adjust on the line side.

I can't get your last link to work - says No Thread specified. If you followed a valid link, please notify the administrator

Angelo888
21-10-2011, 11:53
hi Steve


Look great.
I was toying with the idea of a big wood lathe but went down the conical path (for the time being at least...) The upper mid I build was so good I thought I'd apply it to all horns and see.

your horns look great, too.:)



Are you considering a tapped horn?

Yes, i am playing with the idea to try out a tapped horn. I know there is improvement possible in the bass section of my system, nevertheless, that i like my basshorn very much. It extends wonderfully down to below 30hz, and has great punch and control. But there are also shortcomings, which i would like to overcome with time. What i would like to have, is more even and extended vertical radiation of bass, ideally from a bass row. The exit of the Tapped horn is relatively small, what indicates directionality. So maibe a bass row of for example 4x 12" woofers each side , and a tapped horn below, would be interesting.



I have found they integrated well once sorted (I originally had crossover and Zobel issues) they work really well doing nice deep bass support on normal stuff and where there is sub bass you hear that too. They are fast too not ponderous booming away.

yes, i have read many positive things about these.


What frequencies are you crossing at?

i lowpass the bass horn at 150hz/24db
i highpass low midrange horn at 150hz /6db, lowpass at 1,2khz/12db, the Beyma at 1,8khz/6db, and the S2 blends in at 700hz, but is padded down with Lpad. It just helps to broaden up a little bit soundstage. Its not essencially necessary, and since S2 is a rather expensive driver, and a wast to use in that way, i am selling it, and will replace it with a pair of Coral M100's, which are laying around....



What efficiencies do you have / measure?

The whole system is adjusted to match the efficiency of the Beyma, about 102db/wm. S2, and lower midrange horn are padded down, and the bass horn is active.


Do you find that sound coming off the tweeter hitting the backs of the other horns and interfering a bit to be a problem? I experimented with acoustic absorption there and found it beneficial. Cleans the already pure horn sound up a little further.

It never disturbed me, but definitively worth to make a experiment , and see if it brings some benefit.


5 way really is the way to go I think.

Well, the Beyma actually eliminates the need of a dedicated midrange channel, since it covers nicely above 1,2khz. There are some very interesting 2 way solutions with it.


Do you have one amp and L-pads?

I use the bass horns active, with Inosic RAS300 plate amp, and the other channels Viva Solista SET amp. Lower midrange, and Midrange S2, i use LPad.


I still use passive crossovers but use 5 amps, one per channel and level adjust on the line side.

Many go this route. Have you been able to make direct comparisons , do you feel multi amping improves sound perceavably ?

you can go to my forum, and select DIY Hornspeakers, AV finished.

http://www.audiovoice-acoustics.com/forum/

Angelo

Magna Audio
21-10-2011, 14:22
Thanks for the answers - Very nice ideas there.

I found that removing the L-Pads from my mid, upper mid horns & tweeters and using line level attenuation to be of great benefit to clarity and dynamics for those drivers.
Like a veil being lifted. They were good before but became stunningly clear in comparison without L-pad. Of course I needed 5 amps - 5 lots of speaker cable, 5 line signals to the amps etc. etc. but worth it.

I am trying bigger and bigger amps on the tapped horns.
I use 600W Eminence Kappa Pro LFII's for the tapped horns and a good big amp does grab them nicely.
I have started using SE amp on the upper mid and will expand that to mid horn soon I think.

I use the tapped horns 90Hz down to 20Hz and at that long wavelength there is very little directionality really. I run the tapped horns in the corners and gain more efficiency that way but they do not boom at the levels I listen to, even loud levels. You can pressurise the room so its uncomfortable if you want to or make ornaments vibrate on demo's but that is not really hifi:)

Ah you have S2's - yes they are expensive and interesting to see you are dropping them from the line up...

Once again thanks for sharing us your excellent project.

Angelo888
23-10-2011, 23:44
Thanks for the answers - Very nice ideas there.

I found that removing the L-Pads from my mid, upper mid horns & tweeters and using line level attenuation to be of great benefit to clarity and dynamics for those drivers.Like a veil being lifted. They were good before but became stunningly clear in comparison without L-pad. Of course I needed 5 amps - 5 lots of speaker cable, 5 line signals to the amps etc. etc. but worth it.

Your report is quit interesting and relevant. You are not the only one to mention that. I am thinking to use more one amp to driver my lower midrange horns. A complete active package seems also interesting to me. Digmoda makes some advanced plate amps for multi amping, with crossovers and room correction. They use ICE power amps. Thats a alternative i am studying. Don't know IMHO if ICE power amps do combine with high efficiency horns. A other alternative i was thinking about is to use Hiraga Le Classe A power amp. There is one at ebay right now, and its price seems reasonable as well. But there are two versions. One with 20 Watts, another with 30 Watts. The one with 30 Watts seems quit superior according to Stephano Bertoncello. There are some DIY versions of that amp. But i am not in hurry. I am studiyng which direction to go. I read with interest about your experience with Class T amps. I had a Trend's Audio T-amp a few years back. But it had too much treble, and clipped very easily.



I am trying bigger and bigger amps on the tapped horns.
I use 600W Eminence Kappa Pro LFII's for the tapped horns and a good big amp does grab them nicely.

I have measured my lower midrange horns, and they start to get out of steam starting at 200hz. I doubt the tapped horns work clean up to 150hz. And that is a very important frequency range, from 70hz to 150hz. Thats where all the beat comes in.



I use the tapped horns 90Hz down to 20Hz

I think even at 50hz there is directionality. Made some sweet spot experiments in the last few days, and i was impressed, putting a 50hz sin wave, and walking around the room, how perception of the signal changed. In the middle of the room, signal was reduced at least 50%.......


I run the tapped horns in the corners and gain more efficiency that way but they do not boom at the levels I listen to, even loud levels. You can pressurise the room so its uncomfortable if you want to or make ornaments vibrate on demo's but that is not really hifi:)

hehehe, thats cool. I like that.....:)


Ah you have S2's - yes they are expensive and interesting to see you are dropping them from the line up...
.

Well , i like they are still in high demand and rare. So i can sell them , without loosing money..... The Beyma's are definitively MUCH better above 1,2khz, no way of going back to compression drivers......

Angelo

Magna Audio
07-11-2011, 16:02
Sorry for the delay in replying - I kind of lost this thread for some reason...

yes the tapped horns only work upto 100Hz really. I cross at 90Hz. I have those fairly big mid bass horns working from 90 upto 330Hz.

Interesting about your 50Hz studies - I definitely prefer the tapped horns in the corners to swapping the other way with the drivers - seems right like that sound wise. Perhaps it is direction.

I was looking at miniDSP but remain a bit unconvinced. I'm getting a really good sound now with the corrections I've made to the Tapped and mid bass so they integrate nicely and are a real strength. Together they make bass like no box solution I've come across. Of course miniDSP might do even more for me - oh well that might be a longer term aim now.

Tell me more about the Beyma's. How high do they run up too?

I am looking at Raal Lazy Ribbon tweeters - nice but expensive. With luck I will be able to test a pair in my system for to see how they sound... Essential at that sort of money.