JERICHO Horn Speaker

DIY Horn Speaker


Here is my HORN
It is self made. I use 21mm MDF.
The driver is a FOSTEX FE 208 SIGMA
Diameter of the Driver is 230 mm. The complete Horn has a efficency of 100 dB with 2,83 Volt input in 1 meter. The Driver has a Impedance of 8 Ohms so 2,83 Volts are exactly 1 Watt input power. The Dynamic is enormus. The plan was in the German Magazine " Klang und Ton" issue 2/96 and it is called the JERICHO HORN. I am very happy with the sound. This is the perfect speaker for single ended amp's.

Picture of the FOSTEX FE 208 SIGMA driver


Specifications of the FE 208 Sigma Driver


Click on the picture to get the plan. Use your mouse right click to save it.

Partlist for the wood :
2 Sidewalls 1170x500 mm
1 Front 742x360 mm/21
1 Back 1170x360 mm
1 Bottom 481x360 mm
1 Top 462x360 mm
Part 1 148x360 mm/35/43
Part 2 692x360 mm/45/13
Part 3 698x360 mm/6/0
Part 4 691x360 mm/0/0
Part 5 200x360 mm/21/10
Part 6 292x360 mm/25/65
Part 7 70x360 mm/45/39
Part 8 60x360mm/40/40
Part 9 95x360mm/45/45

The correction network. It is used to get a smoth frequency cure in the middle. This you can see in the frequency picture. Without the correction network you get the upper curve in the middle frequency's.
R2 and C2 are to smooth the impedance curve.
You don't need them if your amp is a transistor design
R2= 10 ... 33 Ohm, C2= 15 uF

L1=1,0mH - air coil, wire diameter 1,4mm or more
C1=2,2uF MKP or MKP-SN or better one
R1= 10 Ohm / 20 Watt Metall, I use 10 * 100 Ohm / 2Watt parallel

Frequency response of the Horn


Building Instructions

The only damping material in the Horn is about 50gr. wool just behind the driver. You can experiment with the amount of wool to get the bass respose you need for your room. 50gr. is in my opinion a good starting point. I got the best results with it.
Also a good idea is to double the back side and the side's of the mouth opening to get no coloration from "swinging" side and back wall's. See on the picture beside. This picture was send to me from someone who has build the horns. ( Sorry I forgot who it was, please give me a notice when you read this. )

Woodwork

There is nothing to say, look at the picture.

Some mail from builders

Subj: Jericho horn
Date: Di, 15 Jan 2002 18:06:19 Mitteleurop. Zeit
From: "Anil Advani"
To : UHAUMANN

Hello!
I used the basic design of the Jericho horn but modified it to take Lowther PM4A drive unit [I am using the 15 ohms variety]. Took exact 7 days 10 hours per day with 3 of us working together to complete. I used 3/4" ply wood for the entire cabinets, and rounded out each bend in the folded horn. So the cabinets are a bit larger than the original Jericho plans. I used 1/4" cork sheeting to line the entire horn length thus smoothing out the contours even more. I used a felt padding behind the driver in the compression chamber. The chamber was adjusted to a vol of 5 liters and the horn throat is 60 square cm. I also put additional side panels and a double sheet of ply for the bottom and back of the cabinets. The side panels are cut in a nice curved shape [will post photos of the speakers shortly to a website] so the whole speaker has a very pleasing look. The sound is amazing, this is like achieving audio Nirvana! The portrayal of every recording is superb, all the tiny cues and details in the recording are clearly "visible". Soundstage extends beyond the speaker boundaries and is very wide and deep. Bass is just right, not lacking - very natural. I wonder why most people who write about their impressions on horn loaded full range speakers complain about less bass - I think the bass is tight, tuneful and correct. Not lacking!


Cheers!
Anil
[from Bangladesh]

Literatur :

The plan was in the German Magazine " Klang und Ton" issue 2/96 and it is called the JERICHO HORN.


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I take no responsibility for the accuracy of information in these pages, or consequences of doing something stupid after reading these pages. (c) Ulrich Haumann, 1999 - 2010
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