Back to the 138 esrs. Any thoughts of how would these perform in front loaded horns?
It does not want to have so much Gain from the Horn in the ower Frequences

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Sure it does. More gain the better. You can always loose what you don't need. Rather hard to boost what isn't there to begin with.
Another question, if you were to build the recommended BR enclosure for the f120a from the fostex site and later replaced it with 138es-r, would not that be an improvement?
And please tell me if Im wrong here doesnt a more optimal box like the swans etc only effect the lower frequency below 2000hz...?
And please tell me if Im wrong here doesnt a more optimal box like the swans etc only effect the lower frequency below 2000hz...?
sharptouch said:Another question, if you were to build the recommended BR enclosure for the f120a from the fostex site and later replaced it with 138es-r, would not that be an improvement?
I couldn't find an enclosure on the Fostex or Madisound site specifically recommended for the F120A, but from my personal experience with several "factory" designs for other FE & FF series drivers, they can be (to put it diplomatically) hit or miss.
This driver will probably never be as popular as the far more affordable FE/FF series, and not only due to the price & limited availability issues. For some DIYers, the sub 90dB sensitivity and single digit power levels of their beloved SET tube amps is a tough combo. Therefore there will likely be few experimental designs. One that I can assure does work very well indeed is an adapted version of the Planet10 Fonken design. A few folks managed to hear these briefly at Dave's August love-fest, and subsequently Bud Purvine spent several months further fine-tuning the enclosures and possibly the drivers.
And please tell me if Im wrong here doesnt a more optimal box like the swans etc only effect the lower frequency below 2000hz...?
more optimal for which driver T/S parameters & applications?
I couldn't find an enclosure on the Fostex or Madisound site specifically recommended for the F120A
Factory BR: http://www.fostexinternational.com/docs/speaker_comp/ff_enc.shtml
Another question, if you were to build the recommended BR enclosure for the f120a from the fostex site and later replaced it with 138es-r, would not that be an improvement?
Very unlikely. A box is designed for a specific driver, so stuffing something that wasn't intended to go into it rarely works well.
And please tell me if Im wrong here doesnt a more optimal box like the swans etc only effect the lower frequency below 2000hz...?
'Different' rather than 'more optimal' would be the operative phrase here, and as Chris points out, it depends on which driver you're talking about anyway. Assuming there is a Swan for that unit, it might be more optimal, it might not, depending on your own taste, system and preference.
How high up a horn nominally works depends on the design upper corner frequency. You certainly don't want it working up to 2KHz. 300Hz is about the practical limit, depending on the design, give or take, or you'll run into imaging problems, and also issues with the outputs from the two distinct sources combing with each other.
Man, that almost looks like it would make a real nice Mid-Low FLH driver; just a little too low efficiency.Scottmoose said:
You tell me.
300Hz exponential horn (I don't like the exponential flare, but it's quick). St = 6.895in^2. Sl = 159.63in^2. Length 22.6in. Vb = 0.5 litres.
Another 5 - 10 dB efficient...
I was wanting to do the same with a pair of 108ESR-IIs I've got; nice tone, but, same problem.
It's hard to find something to work in that range ~ 200Hz - 1000Hz without going to GOTOs, etc.
Sure would have saved a lot of money...
Robert
The FE138ES-R are available in Europe.
I have information from the distributor that only 25 pairs will be sold in Germany.
http://www.audioconnexion.de/Photos/fe1380esr.jpg
I have information from the distributor that only 25 pairs will be sold in Germany.
http://www.audioconnexion.de/Photos/fe1380esr.jpg
Picture of fostex fe138esr in nagaoka TL
Anyone try the Nagaoka TL for the fe138esr? The sigma basckets are easy to mount in front horns since they have a front mounted rubber gaskets. The TL sounds very good. Driver images well treble is extended. Bass in TL is very defined and detailed sometimes surprises me with deep rumbles on HT.
Anyone try the Nagaoka TL for the fe138esr? The sigma basckets are easy to mount in front horns since they have a front mounted rubber gaskets. The TL sounds very good. Driver images well treble is extended. Bass in TL is very defined and detailed sometimes surprises me with deep rumbles on HT.
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kloss have you found the 91.5 db rating to be accurate? any and how much db box loss/the tl? how deep into low watt set's can you go with them in a small room without compromising dynamics? would the fostex rec. (odd lost in space low budget sci fi flick looking), blh help if using a low watt set?
fe138esr
91.5 seems to be correct. I only tested in my home. Will test a pair at madisound. The TL doesnt cause loss. The bass is strong for such a small driver. In the swan TL it performs about the same. I preferred the tall nagaoka TL to the swan. Soundstage is taller you dont hear the TL since its so tall in the swan its slightly more colored.
91.5 seems to be correct. I only tested in my home. Will test a pair at madisound. The TL doesnt cause loss. The bass is strong for such a small driver. In the swan TL it performs about the same. I preferred the tall nagaoka TL to the swan. Soundstage is taller you dont hear the TL since its so tall in the swan its slightly more colored.
Kloss,
Is that a TL you designed, or the Nessie looking cab design that comes with the drivers?
What are you using for a tweeter?
That's a tiny picture, hard to make out...
Robert
Is that a TL you designed, or the Nessie looking cab design that comes with the drivers?
What are you using for a tweeter?
That's a tiny picture, hard to make out...
Robert
kloss, i didnt think they were both transmission line designs. the "nessie" almost looks like a benjamin olney acoustic labyrinth/folded pipe length ~25% of the wavelength of the Fs and xsectional ~the same as Sd. the swan looks more like a tl. i had thought both were horns. thanks for telling us why you choose the nessie over the swan. seems to me like one 5'x5' sheet of bb (~62lbs), would be enough for one speaker, how did they end up 100lbs? a listening session between them and the spawn bvr some have built would be interesting, any guess of the outcome?
The Nessie is just a straightforward resonant tube (well, two of different cross sections), ususally tuned to ~ 1/2 wave Fs. The Swan is nominally a BLH with the expansion created by a cascade of straight manifolds.
FYI, strictly speaking, a TL is a straight line damped to ~aperiodic levels, & with a near flat impedance curve. That's where it gets its name (although as it happens, Bailey's line was slightly tapered).
FYI, strictly speaking, a TL is a straight line damped to ~aperiodic levels, & with a near flat impedance curve. That's where it gets its name (although as it happens, Bailey's line was slightly tapered).
Scottmoose said:(although as it happens, Bailey's line was slightly tapered).
Bailey's line had about a 1.7:1 taper, a pre-chamber (as in daline) and is slightly mass-loaded with a restricted terminus. It is the model on which the Radfords, IMFs, and TDLs are all based.
http://p10hifi.net/planet10/TLS/classics/Bailey-WW-TL-map.pdf
dave
It should be noted that the TL in Vivra's US Patent (which preceeded Bailey) is a straight, end loaded pipe.
http://p10hifi.net/planet10/TLS/classics/Vivra-TL-patent-US4164988.pdf
dave
http://p10hifi.net/planet10/TLS/classics/Vivra-TL-patent-US4164988.pdf
dave
FE138ES-R report in the German Magazine Hobby Hifi is out.
Some Mesurements and the suggestion of a filter. For the Enclosure they suggest the Fostex BK 108, but they did not build it, just simulated.

Some Mesurements and the suggestion of a filter. For the Enclosure they suggest the Fostex BK 108, but they did not build it, just simulated.
Super tweeter is LCY K100
Would post another picture but all I have is to large or to small. The TL is nagaokas design for fe138esr. They are heavy much is doubled ply. Some solid cherry. I still think most BLH designs are really TL but YMMV.
Would post another picture but all I have is to large or to small. The TL is nagaokas design for fe138esr. They are heavy much is doubled ply. Some solid cherry. I still think most BLH designs are really TL but YMMV.
Re: Super tweeter is LCY K100
Are you sure? Nagaoka passed away some years ago.
If it expands toward the mouth, it's a horn. Impedance matching at Fc might be a design goal, but it doesn't determine whether something is a horn or not.
Kloss said:The TL is nagaokas design for fe138esr
Are you sure? Nagaoka passed away some years ago.
I still think most BLH designs are really TL but YMMV.
If it expands toward the mouth, it's a horn. Impedance matching at Fc might be a design goal, but it doesn't determine whether something is a horn or not.
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