Frugel-Horn Mk3

My apologies for pushing this OT a little (I'll claim an interest in the twin 3" driver option of FH3!) ..Fostex decided to continue the FE83En - I assume there must be a customer who buys a decent quantity of them to make it worth their while. I thought maybe the application for the FE83 could be as a tweeter but Fostex still advertise it as 'full range'. I'm a bit confused, it seems inconsistent with the comments I've received recently about how awkward the FE83 is to work with given it's current T/S parameters verses the FF85 - the recommendation from Scottmoose is to use the FE83 only in a large horn - in which case I'd be better off using the 126En. I'm not expecting you to know what's going on inside Fostex but is there something that I'm missing here ?
 
frugal-phile™
Joined 2001
Paid Member
The japanese like the little drivers. I still expect that is where most of the Fostex still go to Japan.

When i was looking at 3" for a small driver the FE8x both needed boxes near as big as the mFonken to get any bass. FF85 was the only one that fit. And it works better all round. With its exotic surround it really is a budget Sigma.

dave
 
frugal-phile™
Joined 2001
Paid Member
The japanese like the little drivers. I still expect that is where most of the Fostex still go to Japan.

When i was looking at 3" for a small driver the FE8x both needed boxes near as big as the mFonken to get any bass. FF85 was the only one that fit. And it works better all round. With its exotic surround it really is a budget Sigma.

dave
 
Well, I'm still trying to imagine how many 'full size' horns the Japanese want to build that it justifies this driver being introduced and why, if a full size horn is needed, they don't prefer the 126 with it's higher sensitivity and lower Fs. The A5/6 appears to be much more flexible for smaller enclosures so the same question doesn't seem to be relevant there. I'm a curious person !

With regards double driver FH3 - is there something 'clever' to be done by positioning a 2nd 3" driver so that it is located at a strategic point along the horn in terms of reducing ripple in the FR ?
 
Well, I'm still trying to imagine how many 'full size' horns the Japanese want to build that it justifies this driver being introduced and why, if a full size horn is needed, they don't prefer the 126 with it's higher sensitivity and lower Fs. The A5/6 appears to be much more flexible for smaller enclosures so the same question doesn't seem to be relevant there. I'm a curious person !
Who knows with what rigid calculus (if any?) a particular manufacturer ( Fostex in this case) assesses the needs of their most selected client base?

i.e. how well did it work for the long time largest auto manufacturer? :D

For more than a few decades, much has been posited over the different cultural/musical sensitivities of the Japanese "audiophile" & DIY market, and how that might affect the design and marketing strategies of electronic and speaker manufacturers.



With regards double driver FH3 - is there something 'clever' to be done by positioning a 2nd 3" driver so that it is located at a strategic point along the horn in terms of reducing ripple in the FR ?
I'd beware of thinking out loud over attempts at "cleverness"; just build it, (measure if you like) and verify with other listeners first before prematurely going public ;)



and, yes, you are addicted :up:
 
BTW, what particular 'ripple' are we discussing here?

I'm thinking of the ripple in the frequency response that one expects from a horn that is smaller than it would ideally be if there were no limitations (what MJK calls 'consistent') and the reason why the 'pipe' has to be suffed behind the driver. Maybe my thinking is all screwed up.

Anyhow, I figure that the FH3 has resonances between the pointy closed end and the choke point just before the flare - why people have said it looks like a Voigt. And I am learning that with these things you put the driver in a place to reduce harmonics / resonances to smooth out the FR. So if you have two drivers maybe you have another degree of freedom that allows the constructor to cancel additional harmonics that one driver alone can't do.

In my ignorance I think this allows a twin-driver FH3 to be a better horn than a single driver FH3.

just build it, (measure if you like) and verify with other listeners first before prematurely going public ;)
and, yes, you are addicted :up:

I'm afraid that my crazy thoughts often spill out prematurely onto the forum, all to my embarassment I'm afraid! Actually, I have no equipment for measuring speaker performance but my interest grows and perhaps I should think about how to do that.
 
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Bigun;

all kidding aside, my gut feeling is that dual FF85K would work best if installed as close together as possible - we'll likely play with that ourselves sometimes after the long weekend

Probably two drivers some distance apart creates their own nasty surprises with interference effects at the listening position so your gut feeling is to be trusted.
 
Probably two drivers some distance apart creates their own nasty surprises with interference effects at the listening position so your gut feeling is to be trusted.


actually, I should have said "we'll play with that ourselves in the FH3 sometime after the long weekend" - my gut feeling was based on trying dual FF85K in a "milli" sized box a while back - sounded quite well, but the experimental paint finish was a disaster
 
Well in that case I'll look out for some interesting reports sometime next week !

The learning continues...

Can you tell me, what is the as-designed cut-off frequency for the FH3 (I guess it's not supposed to be driver dependent but just in case it is I'll specify the FE126En) when used in 'free space' and 'against a wall' ??

Is this the same as the cut-off of the low pass filter formed by the choke, and is it the same as the mouth cut-off ?

If my questions don't make any sense to anybody I won't be surprised - these things are still a bit mysterious to me !
 
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...what is the as-designed cut-off frequency... Is this the same as the cut-off of the low pass filter formed by the choke, and is it the same as the mouth cut-off ?

Hi Biggie, you want the horn to have a certain bandwidth. If the low-pass was in the very same range as the mouth's cutoff, it would be a very quiet horn :) So it must be higher.

From what I've read (not claiming to really understand), the F3 of the total design would be based on the quarterwave action, the bandwidth of which is below the horn action. In other words, the "mouth cut-off" is where the horn runs out of bandwidth but there's something else below that, filling in the very low end, which is a function of the design's effective length (rather than mouth size). Or so I've read :)

In my limited experience, the horn loading adds a lot of excitement to the sound. When a soundtrack or orchestra suddenly kicks in with tympani or brass, it's very dynamic and effortless. The only quasi-problem I've encountered is that the horn-loaded bandwidth can outshine the non-horn loaded but that's a nice problem to have.

This design, by the way, looks exceedingly clever and yet at the same time, beautifully simple and compact.
 
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Hi Biggie, I stress that I'm just a newb but here is another way to think of it.

The horn's response is a hump (maybe a nice flat plateau in-room). The choke low-pass would be the right side of the horn's hump (which will ideally sum flat with the rest of the system).

It seems the system's response, going from lowest frequency to highest, would be: quarter-wave response, blending / summing with the horn action's low end, across a plateau of the horn's flat bandwidth, moving on to the low pass of the choke, chosen so that it sums nicely with baffle diffraction (presumably), then on to just the direct radiation of the driver at some point.

(Of course room modes are another set of variables so this imperfect description is idealized, I guess.)
 
So What Becomes Of The FH1 Owners?

I'm one of the 15 intrepid souls that built the original FH1 flat pack kit. It's funny how time flies; I've been so busy listening (and enjoying them) that I haven't even put the supra-baffles on yet! I'll get to that in the next decade.

I must admit a tinge of jealousy regarding the rework of our mighty little speaker; the FH3 looks a LOT easier to build, and I like its sweeping, curvy design aesthetic even more than the FH1. What really makes me jealous is the assumed improvement in performance. The original FH1 had some issues in "cuppiness" and took a fair bit of time to tune and get right. A wee bit too fussy - and not forgiving enough for the average home-builder, if you ask me...

I just learned through this thread that the FE126E driver has been discontinued. As Murphy's Law has it, I'll probably now end up needing a replacement driver - since they are no longer available.

My question is, what other drivers might be a good drop-in replacement for the 126E? Will the new 126eN play well in the original FH1 with some chamber tuning?

Regards all,
Dennis
San Diego, CA
 
My question is, what other drivers might be a good drop-in replacement for the 126E? Will the new 126eN play well in the original FH1 with some chamber tuning?

Regards all,
Dennis
San Diego, CA


well as far as Fostex is concerned (and for all they care if DIYers don't share their POV), and the numerous owners of Horneshoppe Horns who've already followed Ed's lead - the FE126eN is the drop in replacement / upgrade (don't be surprised to find a temporary surfeit of the earlier model showing up on the used market)
 
RJBond:

Believe it or not, the biggest fix for "cuppines" was to just break in the driver! I also played with wall damping and tuning (size) the CC and discovered that it was just too finicky for my own personal agenda, hence my earlier comments. No fault of the designers, I now understand the strong implication that this is not a out-of-the-box "kit" per se - but rather a platform for one to tinker and experiment with. It will probably not sound quite right just by building to the print. One needs to tweak the driver, CC, etc. to make it shine. And shine it does once things are right.

I decided to enter the horn arena with these because I have rather limited speaker placement space in my room; their small size and visual aesthetic were big draws. All in all I feel it was a successful project. The fact that the FH1 platform has now been abandoned for a different internal structure speaks loudly...there are apparently better ways now learned to achieve the same objectives.

Go back through this thread and do everything that the experienced builders have suggested. I think you will ultimately be happy, but it will take some effort.

Cheers,