Frugel-Horn Mk3 Builds & Build Questions

I am a new at building speakers and will be starting with Mk3's as my first build. I have already cut out most of the pieces and should start assembly of the cabinet this follow weekend. I have purchased CHP-70's to put int he MK3's. For the first 100 hours it is recommended to keep the volume low. Should I use the finished Mk3 cabinets or can mount them to a piece of wood and run them for 100 hours on a low volume so they are ready for use when the cabinets are done?
 
I am a new at building speakers and will be starting with Mk3's as my first build. I have already cut out most of the pieces and should start assembly of the cabinet this follow weekend. I have purchased CHP-70's to put int he MK3's. For the first 100 hours it is recommended to keep the volume low. Should I use the finished Mk3 cabinets or can mount them to a piece of wood and run them for 100 hours on a low volume so they are ready for use when the cabinets are done?


or even the cardboard box in which they were shipped - set to low simmer with your favorite thrash metal headbanger "music" on repeat and let 'er rip


100hrs is only a little over 4 days

OK, kidding about the music choice- Mark has pretty good recommendations for driver break-in on the commercial section of the forum
 
I recently completed construction of a pair of these gorgeous speakers, and have been using FE126en's in them. In some respects, the sound of the speakers as I have them configured is impressive -- they image like crazy and bass response is fast and tight, sufficient for my taste even without corner loading -- but, for all the messing around with stuffing I've done, I've been unable to get high frequencies to sound natural. What treble there is is quite shrill, yet it seems to roll off quite significantly much lower than I would like, and sounds somewhat muffled in many cases. I don't have the means to measure and quantify this, but I do know that they are, in their present state, not easy to listen to for extended periods of time, unlike, say, my KEF 107's, PSB Platinum M2's, T6's, and even the humble B25's.

I made the brilliant and not-at-all shortsighted decision to glue them together /before/ experimenting with stuffing, so access to the interior cavities is quite limited.

The amp I'm using is an Aleph Mini I recently completed, and which has sounded to me incredible on every pair of speakers I've tried it on. I've somewhat scrutinized it on the test bench too, hooking it up to the Sencore power amp analyzer I'm fortunate enough to have access to, as well as obsessively ensuring via signal generator and scope that both channels perform as close to identically as I could ever hope for... but I digress

I've tried driving them with a Dared VP-845, a Cambridge 840W, an Odyssey Stratos, and a Gainclone as well, and the story was the same, so I am sufficiently convinced that the problem is not arising from a mismatch of amp and speaker.

I would be most grateful for guidance as to how I should proceed
 
Since the cabinet only functions in the LF, it has little impact on the high frequencies per se. There are a few caveats to that, but assuming you've got some damping behind the driver, and haven't tried to cram half a sheep into the horn, it's more likely the innate HF character of the FE126En which isn't to your taste. What you describe is almost exactly in line with its basic FR; it peaks up a bit around 7KHz (less than the old FE126E, but this hasn't been completely erradicated), and is about done by ~15KHz. So, you're probably either going to need a different drive unit, or add a super tweeter.
 
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Fostex drivers are rather notorious for extended break-in periods ( several hundred hours before they fully settle in), and the FE126E certainly benefits from corner loading that can likely help in tilting the tonal balance more to your taste - or not.

The forward dynamic presentation and frequency peaky/ HF tilted response of the FE126E or FE166E is simply not to all folk's liking. No amount of EQ / digital correction will eliminate those issues without deleterious effects on the music.

Fora such as these can /should advise caution ( i.e. YMMV) when trying any new design topology or device make/type, but if this is your first experience with Fostex in general, or the FE126E in particular, there'd be no way to know that for sure.

You might well be a candidate for other driver, and there are several* known to work in the FH3 - many of which will likely fit in the same cutout if your drivers weren't recessed for a flush fit.

*Alpair7 and Mark Audio CHR or CHP70 are on that list.
 
frugal-phile™
Joined 2001
Paid Member
You have some latitude of adjustment of the HF range by playing with toe-in. You may be able to adjust to get lower & mid treble to be acceptable, this will in all likelihood kill the top octave (which a supertweeter should bring back).

Chris' comment about light bass making the top sound too much should also be heeded.

In the end you may just well be one of those who finds the not so good in the FE126 not tolerable.Different ear/brain have different tolerance to different shortfalls (and they all have short-falls). That is one of the beauties of Scott's design brilliance on this design, that at unlike most boxes that are tightly constarined to the driver(s) they accomodate, one can change the personality of these by changing drivers (and adjusting damping to suit).

Whether it is insomnia, meditation, or purposely mind-altering substances (chocolate anyone :)), that help bring all those little ideas you have accumulated over the years together with a leap of creativity into something special, i'm pretty sure that FH3 is the result of one of those leaps.

If you find that you cannot tame the FE126En, you certainly have sufficient power to overcome the downside of EL70/CHP70 (efficiency) and benefit from a less forward midrange and more extended highs (well at least in the EL70). Do note that the EL70 break-in time exceeds that of the Fostex. Alpair7 (at a cost, $ & the "ability" to bring the warts of your other kit to the fore) brings much the same benefits along with more finese.

And we should ask Ben how he feels about the drivers in his long list of possibilities. SOUND WITH STYLE - CUSTOM LOUDSPEAKERS Frugel Horn MK3 kit flat pack Mark Audio Fostex Tang Band (even if you do tame the FE126)

dave
 
The forward dynamic presentation and frequency peaky/ HF tilted response of the FE126E or FE166E is simply not to all folk's liking. No amount of EQ / digital correction will eliminate those issues without deleterious effects on the music.

I always describe the FE126e as being a "front row" speaker. If you listen to jazz, you've got that table right by the stage with the musician's toes right by your head. If you would find more enjoyment sitting in the back row of a smokey jazz club, the FE108EZ is a better option. My only experience with MA drivers thus far is the 10.2...which puts me in within range of seeing the musicians face, but not so close as to hear every breath.
 
Thanks all for the numerous informative replies. I actually have a pair of CHP-70's I have not yet tried, as my baffle cutout diameter is just big enough to make fastening the driver a challenge. Fortunately, I was not ambitious enough to sink the Fostex into the baffle, so it's just a matter of devising a sufficiently robust kludge to mount them. It'll be a few weeks before I can actually work on these more; having a broken ankle and being off to college sort of impairs productivity with respect to these things. When I do, I'll be sure to post results and perhaps some photos.
 
Unless I misunderstand how the mounting holes are cut, it shouldn't take too much work to get the CHPs to fit as driver cutout opening is within .5mm of that of the FE126E. Note that even though the CHP's mounting flange is wider than the average of the Fostex, due to the pincushion shaped basket of the latter, it won't cover the screw holes, but that'd be an easy fix.



The new FF125WK would fit as a drop-in, but we haven't had time to fully break those in and test in the FH3 mules - they certainly couldn't sound worse than the FE138ESRs.
 
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The issue I ran into when test-fitting the CHP was that I had sized the cutout for the Fostex just liberally enough that the CHP's mounting holes are necessarily far too close to the edge of the hole -- there is not quite enough material to screw into. This shouldn't be too challenging to fix, especially if a supra-baffle is employed.
 
The issue I ran into when test-fitting the CHP was that I had sized the cutout for the Fostex just liberally enough that the CHP's mounting holes are necessarily far too close to the edge of the hole -- there is not quite enough material to screw into. This shouldn't be too challenging to fix, especially if a supra-baffle is employed.


If you do decide to add a supra-baffle, you should consider hogging out a bit of the existing baffle to allow "breathing" room through the material of second layer - something like this - new part for our flat-pak kits - allows for attachment of supra-baffle plates via threaded inserts ( excuse the nasty camera photo)
 

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