Full range drivers, Fostex / Audio Nirvana / Lowther etc

[Borats Baby]

I'm looking at build a pair of speakers using full range drivers.

I cant afford Lowthers but like the look of the Fostex FE206E or Audio Nirvana Super 8 cast chassis.

Both available from here

Question is this :

Am I ever going to get any bass from these units. I'm talking below 40hz as this is what i crave the most.

Is there a cabinet design that really get the most out of these types of units.

Any thoughts chaps.

AN do a 12 inch version of the super 8. Will this be a better bet. ???????

Thanks

BB

[jonjin]

I remember looking at this recently... Fostex, Audio Nirvana, www.diyhifisupply.com, Pi speakers etc etc... basically, I don't think a single full-range speaker will ever give you <40 kHz. You'd need a seperate woofer for that!

JJ

[murray johnson]

A friend of mine made some of the 'BigFun' backloaded tractrix horns and uses Lowther PM6A's in them. These do bass below 40Hz when standing in corners. The downside is the size. These things are about 40" high, 40" deep and maybe 12-15" wide. Get a tape measure out and see how big that actually is. They do sound lovely with a 3W SE amp driving them. I'm sure the cabinets would work with the Fostex 8" units in them but they as a project it is a fairly major undertaking. (He had access to a £100,000 CNC Saw!) Doing it in 19 & 25mm Ply with a jigsaw might be trickier.




The design & construction tips for making these may be found on the web. The designer was someone called Ketil Parow. There is also a smaller 'Allfun' horn but I haven't heard those.

I have all the info on another computer if you can't find it.

[HoopsOnToast]

i would recomend the Hemp Acoustics drivers, especially the FR8....
http://www.spectrumaudio.de/breit/hempFR810HQ.html

can be used in a reasonable sized simple ported enclosure, although if they do interest you, wait until the new ones they have just released apear on the market.

spectrum audio is a really good site, guy there is very helpfull and fast delivery from germany aswell!

the Fostex FE-207 can be used in a ported enclosure aswell, MLTL are also on the cards aswell that should give you decent bass into the low 40's without having to have a horn.

if you dont play all that loud, the CSS FR125S is good, a 4.5" driver that will work in a ported or bipole of reasonable size (small compared to the others) but you will only really get around 90dB as it is only

[murray johnson]

This weekend I received a pair of Fostex FE83 drivers to try in my 'Buschhorn' single driver backloaded horn project. I had been using some Visaton FRS 8's but I suspect these rather cute little Fostex drivers may be a good deal better.


Longer term I have some work to do with the rather lovely 500Hz tractrix horns that the woodmeister Kiang has kindly made for me.

I'll post progress as it happens.

[Anthony]

murray johnson wrote:

This weekend I received a pair of Fostex FE83 drivers to try in my 'Buschhorn' single driver backloaded horn project. I had been using some Visaton FRS 8's but I suspect these rather cute little Fostex drivers may be a good deal better.


Longer term I have some work to do with the rather lovely 500Hz tractrix horns that the woodmeister Kiang has kindly made for me.

I'll post progress as it happens.

i think you'll find the fruit is just going to fall straight out the bottom.

seriously though, those look absolutely beautiful. kiang has some serious skills.

[enbee23]

murray johnson wrote:

This weekend I received a pair of Fostex FE83 drivers to try in my 'Buschhorn' single driver backloaded horn project. I had been using some Visaton FRS 8's but I suspect these rather cute little Fostex drivers may be a good deal better.


Longer term I have some work to do with the rather lovely 500Hz tractrix horns that the woodmeister Kiang has kindly made for me.

I'll post progress as it happens.

Horntastic! Those are gorgeous.
I really want to get my lugs on some speakers in that vein, just to see for myself what all the fuss is about. One day...

[Purite Audio]

Nice horns Murray how are you going to implement them? Keith.

[JPG]

Borats Baby- Have a look at the 'Bruce' Double Frugel Horn.

There is an output at 20Hz, but it is very low about -30dB compared to the 50Hz and up flat response. The response below 40Hz drops, but it is there- I don't know whether there is enough low-frequency for you there.

The Sachiko has a better LF response, but it is bigger, and the plans are still being drawn. It should be fairly simple to build though- it is just flats and rigt-angles, no 43.5 degree type angles there.

There is a long discussion on the DIYaudio.com site about these, which can be accessed through the link above.

JPG

[murray johnson]

Hi Keith,

Drivers mounted to 500Hz horns really need to be crossed over an octave higher ie 1KHz. I have some old alnico 1" JBL 2461's or of course the Vvox units either of which will be happy from 1KHz up. It's what you put below that is the issue. My current bass horns wouldn't really be happy going that high.

I've two options really. Ideally I'd get some larger 80 Hztractrix flares to run from 150Hz or so upwards with an appropriate 8-12" driver or make something like a Karlson or Fulmer style cabinet (see the Karlson website) with a high eff 12" in it. I have some Rola 12" field coil drivers I want to use so this may be theeasier option. I do have to work within the constraints of the room size I have ie 4x4.5m soI can't do anything silly.



On topic. BB this page is a good resource for single driver experimentation.

http://www.melhuish.org/audio/links.html

[purplepleaser]

Very nice.

[Purite Audio]

Murray do you have the address of the Karlson site, I have found a couple of their designs, your horn is beautiful, does the maker have a site? Keith.

[i_should_coco]

Not Murray, but Karlson info is here:

http://home.planet.nl/~ulfman/

Have thought about a pair of these in the past, but not sure. The response looks pretty ragged, though they're supposed to have a nice "kick".

Cheers,
Pete

[Purite Audio]

Thanks Pete.

[konig]

the TNT BFB?

http://www.tnt-audio.com/clinica/bfb_e.html

[anubisgrau]

a big audio nirvana driver (12") was quite a disappointing experience for me, lightweight and not very accurate in 250 liter box.

[jonjin]

anubisgrau wrote:

a big audio nirvana driver (12") was quite a disappointing experience for me, lightweight and not very accurate in 250 liter box.

Thanks for that... there seems to be alot of hype on the manufacturer's website though.

JJ

[HoopsOnToast]

anubisgrau wrote:

a big audio nirvana driver (12") was quite a disappointing experience for me, lightweight and not very accurate in 250 liter box.

did you try them in open baffle? they are supposed to be good for that ;)

[PARAGON]

Building the Sachiko is taking a while - my jigsaw nearly caught fire the other day, I think it may go on strike...!

However, it seems all the effort will be woth it in the end.

[anubisgrau]

HoopsOnToast wrote:

anubisgrau wrote:

a big audio nirvana driver (12") was quite a disappointing experience for me, lightweight and not very accurate in 250 liter box.

did you try them in open baffle? they are supposed to be good for that ;)

it performed much better with a different amp - dropping a classic jean hiraga amp (not sure but i think around 20W of pure class A) in instead of 2A3 SET brought abetter overall balance. it definitely has apotential - the overall tone is correct, for even response it just needs a carefuly tailored cabinet instead of a wierd, huge sextagonalbass reflex box. i have no other explanation why would a 8" fostex go subjectivelydeeper than AN.it also seems to benefit from a shorter listening distance - not really a nearfield, but close.