Fullrangedriver Forum

As you've clearly found in your research, to do proper justice to TL design of any type, the enclosure must be optimized to the the specific driver's TS parameters. 

There are many more mathematically savy folks who have already crunched the numbers for enclosures for either of the mentioned flavour of drivers.  AFAIK, the best library of these designs is :

http://www.planet10-hifi.com/boxes.html

FWIW, I've built many of the mono and bipole MLTL designs posted on Dave's site, as well as the mini-onken, for both the CSS & Fostex.  I've also recently built a pair of the 48" triangular TL per the Jordon design, and have posted my comments regarding same on another thread.

I make no apologies for the fact that my particular taste continues to return me to the Fostex drivers in every case where a comparable design is suitable to either brand.

Of all of the enclosure designs I've built using either the FE127E or any combination of WR125/ tweeter & FR1256, my absolute favorite is the mini-onken.   With the slot ports and internal driver brace (essential!), a little trickier than a simple unfolded TL, but better sounding to my ear, and much higher WAF at mia casa.


Having said that, my favorite of all is the FE108E Sigma in Ron Clark's A126 design BLH. My initial pair was seat of the pants modified from Ron's drawings, and I've been too busy with other projects to follow up if he's revised his plans to optimize for the 108.  If you can live with the room requirements, it's been my experience it can satisfy more than any MLTL.

Last edited by chrisby (2006-03-31 14:49:02)

Chrisby,

Thanks for the input, you confirmed what I suspected that designs are built round the driver and not vice versa. The A126's certainly look like lovely speakers but unfortunately my situation dictates that I use something in the style of the VTL enclosure, to make the speakers as unobtrusive as possible and take up less space in the room.

Ghpicard,

Thanks for the suggestions of the PAWO. I had already considered using that design but from what I understood from reading various threads related to it there were issues with the sound quality that were still to be resolved? It certainly fits the bill in terms of the sort of design I was looking for though.

Thanks for the replies, guess I need to do some more homework and see if I can find a suitable design(s) and if not try and learn enough to make one.

Cheers,
Ewan

westend wrote:

The recommended Fostex design for the FE126 has a lot of WAF, I'm told. Chriby built a pair recently so he could answer as to the comparative quality of the sound. I saw a pic of them over at Decware and they looked very nice.

After compensating for difference in sensitivity, I found the monopole MLTL for FE127 preferable to the Fostex hybrid BR/Horn for FE126, particularly in the extension and clean articulation of the bass. 

If you don't have the space to accomodate a BLH at least the size of the Hornshoppe, or the wall space for something like the Cornu spiral horn don't bother with the FE126 or 108.  As I've stated, Ron's A126 is the best I've heard to date with these particular drivers.

Not to sound like a broken record ( any of you young-ens ever heard a vinyl LP? ), but the mini-Fonken delivers the bestest bang for buck in any of the cabinet designs I've built for the CSS drivers or the FE127, and sorry Tom but that includes a group concensus on two pairs of the PAWO design. 

Yes, Doctor Dave the mad tweakologist from Planet10 is working on some treatments for the series of Fostex drivers under discussion, hampered only by the current shortage of inventory and time.  We've currently got a pair of the 127's running in the Fonkens, and it's quite an improvement, and hope to fire up the 126s in horns this weekend.

Updates forthcoming, possbily including some measured graphs, pictures, etc.

cheers

Chris

There is no reason you couldn't try adapting the Fonken to a VTL/PAWO aspect. The biggest worry with any of the shallow cabs is the early reflection off the back wall -- Max's FR125 bipoles in this format illustrate the problem as well.

I haven't published the exact Fonken design yet, but other than the spacing of the slot port dividers it is exactly the same as the miniO. You might find you need to fill the bottom with sand to make the design as large as the PAWO or VTL (or you could just make it smaller.

dave

Yes, A108, A126... maybe A<other drivers>,

We've had the 108 in our A126 -- with too much CC, still sounded awesome -- more finesse than the stock FE126 and lacking the rough edges the stock FE127 & 126 both display. We had them set aside while we played with the proto-Frugel-Horns. The success of the updated Fonken had us pulling them back out to listen to the newly modded FE126...

One thing that i just can't get over is how good the bass is on the A126.

dave

Greets!

FWIW, the FE108ES requires a teeny CC if SS driven, so maybe will work if dialed in with some series R.

GM

So theoretically speaking, I could build an "A108" "jus" changing CC volume ?

Will it work, yes, is it the optimum design for the 108,no.
ron

planet10 wrote:

There is no reason you couldn't try adapting the Fonken to a VTL/PAWO aspect. The biggest worry with any of the shallow cabs is the early reflection off the back wall -- Max's FR125 bipoles in this format illustrate the problem as well.
dave

Oddly enough I'd had this mad idea last night to take the mini-Onken design and try to flatten it, but from your post/comments it sounds like it wasn't such a mad idea. I assume if I were to attmept this I'd need to retain the box volume of 13L and the port lengths/volumes but adapt them to alternative orientations to allow the box shape to be flatter? Also do you have a link to the Fonken design, or any information on it that I could see?

Regards,
Ewan

planet10 wrote:

Just posted Fonken plans in the box plan library ... I'd suggest stacking the ports along the back, mirror image the boxes, then you can set them in or out and use that to help tune for the room.

http://www.planet10-hifi.com/boxes.html

dave

Note: Fonken is a planet10-hifi commercial product but non-commercial use is encouraged

Hi dave!

Im finally getting my fe127e drivers on monday (12 pcs, going for three pairs of speakers) and was going to start the build on your recommended Ref 127 bipole later that night.. Now im getting secound thougths

With your latest experience with the fonkers and everything, wich do you prefere?

Should I stick with the ref 127 bipole or is the fonken a better alternative? Going to use them with mod T-Amp if you remember our discussion.

How does this look?  ... same height as PAWO, 1" wider, 1 1/2" thinner. Will need a stand of some sort (and attention to early reflections off the back).



I'm hoping to get the wall one even skinnier -- how many people actually have walls they could mount them on?

dave

Last edited by planet10 (2006-04-01 20:55:23)

Someone knew i couldn't just do 1... hopefully these 3 give some ideas...



Limited by the driver depth -- based on the golden section

planet10,

Wow! Thanks for the links to the Fonken and for the modified/flat versions. I think the Wall Fonken design pretty much hits my design criteria spot on, plus the girlfriend has just looked at the design and said she wouldn't object to having them in the lounge .  Just a couple of quick (and probably obvious) questions regarding the design, I'm right in assuming that the ports are the same size/length as the standard Fonken and the baffle is still 3/4" thick?

Thanks again for the modified designs/ideas, it's much appreciated.

Regards,
Ewan