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Custom 3-way horn

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3-way custom
51K views 60 replies 26 participants last post by  Champster  
#1 ·
Here is a quick rundown on the build of the speakers I use in my 2-channel rig. This is the second version. The previous were corner horns with JBL guts.

First some MDF and Baltic birch to build the skeleton.

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#2 ·
Here is a closeup of the four layers of kerf MDF that make up the sides. I have filled it with glass beads used in bead blasting. This stuff is finer than sand and pours like water.

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#3 ·
Here I'm starting to veneer the cabinets with sapele pommele. I used Heat Lock glue that you roll on and let dry. I then afixed the veneer with a steam iron (don't tell the wife).

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#5 ·
These are the feet I machined from some 6061 billet aluminum bar, cut it into 4" slugs and trued up on a metal lathe. There are three per speaker. They had to be able to handle the 300+ pounds per speaker.

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#7 ·
Here is the same speaker from the back showing the open back for the Altec 511B horn with the Altec 802-8G driver. The blue bag around the throat is 2 1/2 pounds of lead shot.

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#9 ·
Thank you. They are a labor of love.

By the way, I used the image button to insert the pics. It is using the cap IMG tag.
 
#10 ·
Here is a picture with the grills on. They are made from a metal mesh covered with some JBL blue grille cloth.

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#13 ·
View attachment 20502
Your speakers look fantastic !

But I have to ask : View attachment 20500


Paul P
I feel I would be a bit prejudice on the point, but people who have heard them agree, they are incredible. They are dynamic, fast, liquid midrange, open, airy and a bottom end that make you think there is a sub somewhere. They can articulate at very low output and still shake the walls when you throw the power on. If anyone is every in the San Antonio area, drop me a line and we'll have a few drinks and spin some vinyl or CD's. Be sure to bring some music you like and are familiar with.

Remember the only person who has to like your stereo is you.
 
#15 ·
Love the beautiful veneer. I need to get started on my speakers soon. I am in envy of everyone on here turning out beautiful pieces of work like this one and mine are sitting in the shed waiting to be started.

Awesome job!!!
 
#17 ·
Each driver has its strong points for making the mix. The JBL 2235H has tight bass and power handling. The Altec 802-8G has the tangerine phase plug and when mounted on the Altec 511B has a beautiful liquid midrange. The JBL 077 gives me that top end sizzle that my other designs were lacking.

The cross over is based on an Altec N501 and JBL 3106. I added the attenuators so I could dial in the horns to taste.

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#22 ·
After listening to a large cinema 3 way loudspeaker from KRIX I think I am very interested in building a 2 way or 3way horn design such as yours.

I was wondering roughly how much would your loudspeakers cost to build minus the wood.

I might have a question or two I'll send to your inbox in regards to horns.
 
#24 ·
I apologize anways. I felt kind wierd after asking the price question.

I have a million questions now in regards to a 2 or 3 way speaker design but I will leave those questions for another thread.

Thanks for causing my bank account to decrease even faster.:bigsmile:
 
#25 ·
I apologize anways. I felt kind wierd after asking the price question.
No apology needed; if you don't ask, you don't get to find out.

I have a million questions now in regards to a 2 or 3 way speaker design but I will leave those questions for another thread.
Look forward to it. If you're not stuck on using vintage components, there are lots of other options.

Thanks for causing my bank account to decrease even faster.:bigsmile:
I know that feeling. What started about 3 years ago as a simple 2ch build has now grown bigger than Ben Hur and much more expensive.
 
#26 ·
AHAHA:D

I wont be using vintage parts. Brand new for me unless I find a deal somewhere. And knowing my luck I will be buying everything brand new.
 
#27 ·
Without veneer there is somewhere around $2000 in these speakers. Most of that from the drivers. The woofers are JBL 2235H, the horns use Altec 802-8G drivers and Altec 511B horns. The tweeters are JBL 077. You can ball park each driver around $200. Then add the cost of baltic birch, MDF and outsourcing CNC machine time. The crossover parts can all be had from Parts Express.
 
#28 ·
Wow these speakers are really something. Can you please provide more detail on the finish? Stain, lacquer , etc. I tried the ironing method using diluted wood glue and had problems applying it evenly. I had small bumps/valleys on the veneer that only become visible with a reflective finish. But yours look impeccable. Maybe I should try using a roller instead of a brush.
 
#29 ·
This is the first time I've ever used the Heat Lock glue and it worked flawlessly.

Pour some glue out
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Spread it with a rubber glue roller
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Let the glue setup
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Do the same to the actual cabinet, so both veneer and cabinet have glue.

Then using an old tshirt and steam iron, I "ironed" the two together. Iron was set med/hi with steam. Working from one corner and going slowely to the other side to avoid trapping any air.
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#30 ·
As for the finish, it is DEFT gloss lacquer. I brushed several heavy coats first. Let it dry for a week and then block sanded it smooth. I then added several more coats with a spray can. This is labor intensive and lacquer does shrink, so you have to go back and add more coats and spray again to remove any orange peel or grain pits.

You can get a good gloss with a urethane with less work. For a piano finish a final sanding with some 600, then some 1000 and end by rubbing it out with some 3M Perfect-It automotive polsih.

If you really want a ultra thick high gloss, you can use a two part epxy bar top finish. It would be like putting 30 coats of lacquer in one step and you don't have to do anything else.
 
#31 · (Edited)
great looking speakers and photos,,

have you ran any measurements on the speakers yet,,??

I'm curious as I have a set of Altec A7-500 with the N-800E cross over and have thought about some minor changes,, the bass is only good to 40HZ and really drops from there,, the horn and driver as you have stated are something to be heard that few speakers will compare,,

curious what you feel the JBL tweeter brings to the overall package and how low does the woofer go since it is about the same vintage as my Altecs with 15" woofers,,

thanks

Derry
 
#32 ·
Here are the specs on the JBL 2235H. It really is a awesome driver that does subwoofer/bass duty. I've had people ask if there is a sub somewhere. No, that's all JBL speaker.

http://www.jblpro.com/pages/components/2235h.htm

I tried Altec 416-8C first and the bass just wasn't there. They need a larger cabinet.

The 077 tweeter adds the high end "sizzle" that was lacking with only a 2-way.
 
#33 ·
Hi

I'm very impressed by the job you did.

as the Altec Horn is no longer avialable do you think is it possible to adapt your design to other horn and compression speaker maker? (B&C)

As the direct radiating woofer has not the efficiency of the horn high frequency range system it is necessary I guess to attenuate the two high frequency ways isn't it?

Design "Voice of the Theatre" like need a little more room...

I'm not very smart with manual labor I will nedd the help of a carpenter to built such a cabinet! lol.

Did the "sonic" adjustment of the speaker was difficult to perform

Is it possible to get the drawings of the cabinet?
 
#36 ·
Thanks for the kudos. They are a labor of love, something to be proud of and, most importantly, the sound is sublime.