Frugel-Horn Mk3

frugal-phile™
Joined 2001
Paid Member
CHR70, CHP70, EL70, Alpair 7 or FE126En

There are no universal designs, but...

From many of the other designs, we know that people want to put different drivers in the box (no matter what the box). In this one, we hope that we can say, "try it, it may well work". We want to know.

We have tried all these (well not the CHP) in the alphas and performance was satisfactory (if you think that is faint praise then consider that our standards are high). These drivers have a fair range of parameters.

For those who will go ahead and try other drivers, look at the key parameters of the specified drivers and if your alternate drivers are inside the envelope formed by the set of TSP then you have a good chance. No guarantees thou.

With a 3" driver you may well have to use a pair per box. Maybe i should try the quad of FF85 i have in FH3 before i install the new set of drivers into the Twin uFonken.

One thing i do know, neither BOFU or FE166eSR will work. One critical parameter kills the idea. Driver diameter > box width :)

dave
 
Could this be scaled for a 166esr? I've been dying to replace my Fostex boxes and this looks a little easier to build then the Austin A166.
I've a pair of 166es-r's an would be interested in following that build. Also curious to know what you don't like about the 166es-r fostex recommended box or did you install them in a fostex bk16?

Btw, i'm located around philly too so if you decide to do the A166 i may be able to help lend a hand on it's angled cuts with my dewalt 10" sliding compound miter saw.
Considered them myself, but don't have good corner space and read of bad results using the standard A166/lower powered amps, plus Ron Clark said they put a good amount of back pressure on the driver so not for wimpy amps. I like my 3watt Fi 2A3 so passed. I don't know how different a redesign of the frugel MkiIII's for the 166es-r would be wrt 3watts of 2A3 power?
 
With a 3" driver you may well have to use a pair per box. Maybe i should try the quad of FF85 i have in FH3 before i install the new set of drivers into the Twin uFonken.

Now that's an interesting idea. :)

One thing i do know, neither BOFU or FE166eSR will work. One critical parameter kills the idea. Driver diameter > box width :)

Yes, a bit of a hitch, that. ;) And you can't just widen it because the drivers require different things; volume, horn length & flare etc. will all need to be changed, making for complete new box designs from scratch.

A166 should be a good box for the ES-R; that's what I'd be inclined toward too.
 
It was not my intention to 'stuff a bofu in and see what happened'. To accomodate a vas of 1.75 cf and an fs of ~45hz you'll no doubt "need a bigger boat". That will mean increased width to accomodate the driver size and line length to increase both the volume and fs requirements. I guess what I was looking for was a cabinet similar in proportions that could accomodate a larger driver. Without knowing the measurements of the fh3. I know theres more to it then multiplying the measurements by x- it's truly a science and something I admire all of your work for.

If such a "boat" couild be built, I'm guesstimating this new one to be ~ 48"x 10" x 12" (roughly 2.2sf if using 3/4" ply). Yup- those are some big cabinets. I'm confident we start really playing with the numbers a bit, they could lose a little girth and be as sexy as their protoge, the fh3.
 
mini - FH3

How about a smaller FH3 to accommodate a single FE83 in each cab for desktop use. I've been considering the Busch Mk1 as a starting point, but the simpler FH3 looks to be a better option.

What needs to change for the FE83 ?

Or is this a crazy idea, horns on desks for goodnessakes
 
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This is more of a serious build for a desk top dont you think

Not at all. I've seen OB on desks, I've seen some neat TLs (Alpair driver) on some desks, we've got Fonkens, 2-ways, Sprial Horns...we've got 'em all. So how about a mini-FH ?

Anyhow, a busy desk ain't so bad ;)
 

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Yeah, this would keep me busy for months if I had one like that.

So back to understanding the new FH3 and horns in general. If I use a small driver and don't ask it to go down as low as the larger driver then I should be able to use a shorter horn with a smaller mouth. Something around 500mm high would be ideal for desktop use as it is close to the top of most monitors/ears.

I really like this FH3, nice curves, simpler construction but great thought, art and science behind it's design. If only I needed a pair of floorstanders. Perhaps I can find an excuse :D
 
How about a smaller FH3 to accommodate a single FE83 in each cab for desktop use. I've been considering the Busch Mk1 as a starting point, but the simpler FH3 looks to be a better option.

What needs to change for the FE83 ?

Everything. A complete new design, from scratch. You can't just shrink or expand this one; the dimensions are critical.

Desktop back-horns in general isn't an ideal way of going about things; esp. not with rear-firing termini. You won't get many benefits & will likely run into a few phase / integration problems.
 
Hi!

Been lurking for a while trying to decide on a design to have a crack at and was always pretty intimidated by the original FH, but this one is getting me excited as the internals look significantly simpler! Two questions...

1. Is it the current (early) opinion that the 126En version does (or will) sound better than the original Frugelhorn? Even if it sounded as good or even slightly worse, the simpler construction still makes it a great design!

2. Is there any point in mounting two 126En's on each cabinet for increased sensitivity? (Sorry if that's a dumb question).

Taz (Audio Philistine).
 
Everything. A complete new design, from scratch. You can't just shrink or expand this one; the dimensions are critical.

Desktop back-horns in general isn't an ideal way of going about things; esp. not with rear-firing termini. You won't get many benefits & will likely run into a few phase / integration problems.

Well, that's the trouble with being a newbie to these things, what looks to be simple often turns out not to be the case !

What I didn't want to consider is a pair of BR boxes, just too boring even if they work well. I may just have to get some wood and do somethings crazy.....