fostex 103 cabinet in 3/4" plywood

fostex 103 cabinet in 3/4" plywood

After building a TQWT and a Zigmahornet I decided to try the Fostex recommended backhorn for the 103. Since 15mm plywood was unavailable I redrew the plans using 3/4" ply and converted all dimensions to inches. Are there any changes I need before I start construction.
 

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Zigmahornet

Hi Faitour, I have heard good things about the Zigmahornet and was planning to build one soon. What makes you choose another design now? something you disliked about the Zigma? and may I ask you to indicate me a link with plans of the Zigmas? I have found a site with pics of it, but no plan.

Jean Hiraga (from l'Audiophile) seem to insist on using thin baltic birch like 12mm and 15mm for his smal tqwp designs rather than pressed wood.

Keep us posted about your results.

Sylvain
 
Faitour,
It looks good to me, kind of a pain to convert them isn't it? I converted a swan-101a in 3/4" wood for my brother's fostex 103, ended up turning out pretty good. I'm sure you will be quite pleased with the BLH. Only thing else I would think of is to bevel out the back side of the driver opening, I've found this to really help with my fostex 108. But maybe you were already planning on doing that anyways.
Fellow North Carolina speaker geek.
Joe
 
Re: Zigmahornet

Sylver300B said:
Hi Faitour, I have heard good things about the Zigmahornet and was planning to build one soon. What makes you choose another design now? something you disliked about the Zigma? and may I ask you to indicate me a link with plans of the Zigmas? I have found a site with pics of it, but no plan.

Jean Hiraga (from l'Audiophile) seem to insist on using thin baltic birch like 12mm and 15mm for his smal tqwp designs rather than pressed wood.

Keep us posted about your results.

Sylvain

Hi Sylver300B
I liked the Zigmahornet alot but I thought that I might get a little more bass out of the backhorn cabinet. I am using a Pilot 246 stereo amp to drive the Zigmahornets and I use the center channel to drive a passive sub to fill out the bass. The wife thinks the Zigmahornets are cute so the new cabinets will have to sound better to get them into the living room. I too had a hard time finding plans for the zigmahornet but I did find a poor jpeg of a plan that I redrew. If I can find the drawing I can email it to you.
 
Re: Re: Zigmahornet

Faitour said:

I liked the Zigmahornet alot but I thought that I might get a little more bass out of the backhorn cabinet.

I imagine you'll get more than a little. I have not heard the zigmahornet, but my brother did listen to them in comparison to his Swans (both with fostex 103). He said the zigmahornet was lacking quite a bit on the bottom end in comparison to the swans. I would imagine the recomended cabinet would give similar results to the swans.
Joe
 
Faitour said:
Why are they not listenable yet? Is there alot of tweaking that needs to be done on them? From what I could see on the plans there didn't seem to be any stuffing required.

At the moment they have a very closed in midrange which makes them unlistenable. We managed to make the Buschorn IIs with FE108es do something similar and we know how we did that, so that is where we will be playing next. I have a bunch of spacers which will allow me to change the size of the compression chamber (the FE103A has a bit higher Q than the FE103).

dave
 
Hi Joe et all,
having built and listened to the Zigmahornet and the Swan 101a (FE108EZ) and also the Fostex recommended backhorn for FE103, my opinion is as follows.

The Zigma is a very nice speaker, yes, in comparison to the 101a it lacks bass but on its own its not that bad. If you need bass then add a sub.

The 101a (which my wife refers to as E.T.) is so far my overall favorite of all the 4" based enclosures I have built. Clean and clear with great bass, yes bass, looking at the driver you would not believe it but run some test tones through it and listen. It does however take some effort as there are IIRC some 30+ pieces of wood per cab but I think its well worth the effort.
The Zigma is much easier.

The Fostex recommended horn does not work for me, simply put it does not sound right and nothing I did ever did made it sound right.
They have been to returned to the soil from whence they came.

I still think the FE103e is the better of the two drivers though, its midrange truly shines.
Maybe with more time the 108EZ would sound as good in the mids but I somehow hold little hope in that regard.

BTW, 15mm plywood is sold as 5/8th's. Almost all plywood is metric nowadays and much of it from Brazil. 13mm is sold as 1/2" etc.


Andrew
 
Re: zigmahornet plan

Sylver300B said:
Many thanks for the nice clean plan! at last, somehting clear..

You are welcome.

I've been meaning to do that for some time. The CAD program i use allows me to generate the drawing in metric and then auto-magically adds the dual unit measurements so the drawing is universal.

dave
 
Josephjcole said:


The 101a is just a variant on the popular (in japan at least) "Swan" series of BLH's. I built one for my brother using a fostex 103 with very good results.

Joe

Wow!! Compared to the Swan, the Zigmahornet looks like the little ugly duck.. But I must admit that my skills are more in line with the Zigmas.. an easy tuned pipe to build.

And how about the Swans? real bass from a 4" driver? I mean, is all this complexity well deserved? or a simpler design with a sub would do? just asking.

Gee, would I like to have you guys living next door and have a listen to our creations..

Sylvain
 
Zigmahornet after thought..

Just a thought. (I know, I think too much..:cannotbe: )

Everyone say the Fe 103 is a terrific driver, but of course, due to its size, it has quite limited low end, but then, why not "2" drivers or even, an array of "4" Fe 103 in a Zigma or Swan cabinet?

Would this ruin the magic midrange?

Sylvain
 
Re: Zigmahornet after thought..

Sylver300B said:
Everyone say the Fe 103 is a terrific driver, but of course, due to its size, it has quite limited low end, but then, why not "2" drivers or even, an array of "4" Fe 103 in a Zigma or Swan cabinet?

I used FE103 versions in bipoles to good effect, and as we design our new horn will keep an eye to adapting it for bipole drivers.

dave