Frugel-Horn Mk3 Builds & Build Questions

Kevin - not all drivers need corner reinforcement in FH3s - certainly it's been my experience that the Mark Audio and TangBand drivers tried to date don't. I have systems in two different rooms - the smallest of which is approx 320ft^2, and the upstairs a much larger open plan. While temporary experimentation has shown me that both would be plenty large enough for even the FHXL - were it not for furniture and WAF - I'm restricted to smaller footprint floor standers with direct forward & top mounted drivers. On the occasions I've played the FH3 & XLs at home they've been primarily been with Alpair 7.3 or 10s, and situated with the rear mouth at least 1ft from back wall, and approx 8ft apart in a 15ft wide room.

Modes are related to ratios of room dimensions, and while something like the FE126 in the FH3 won't rattle the china off the shelves, they will still excite standing waves. The trick in smaller rooms - particularly square ones - is that the physical bulk of treatment required to fully tame bass and other acoustic issues can aggressively impinge on the already constrained space.

In addition to a surfeit of professional and advanced DIYers' websites, formulas and project plans, there's some interesting reading to be found here:
DECWARE / Articles and Papers On Hi-Fi

DECWARE - Article about Setting up a Listening Room without Treatments

Colorful, sometimes grammatically torturous, I've always found Steve's scribblings entertaining and often enlightening.
 
Thanks, Chris. I will check that out directly. The actual room dimensions are 12ftx15ft but I realize that's almost as bad as square.

I figured from what I've read so far that the room would need a lot of treatment, like pretty much total coverage (floor to ceiling corners, HF absorbers in upper edges, and a cloud near the speakers and one over the listening area).
There's not much furniture (bed and computer desk) and no WAF, so I don't care too much about how much space it takes or how ugly it looks as long as I'm relatively sure I'm not fighting a losing battle. I'm not building a studio nor am I looking for the perfect soundstage, but I'd like to get as close as realistically possible.

I have the fe126en's right now but am going to move to the A7.3 by spring (also if you could PM me the price for the supra-baffles you said you still have along with shipping to US 07083, it turns out I'm not as keen as I was on making my own).

Thanks for your help.
Kevin
 
Hi everybody,

I am just about to start building my pair with MA 7.3 drivers. I have a 15mm birch plywood (11 layers). When i rebate approx. 9-10mm I will end up with 5-6mm. Is this enough to support the drivers or maybe I can glue extra 4mm wooden ring inside (behind the driver)?

Thanks for the help,
Philip
 
Philip - I've built dozens of pairs of flat pack kits for that exact driver using 15mm BB, and if you use the (excellent) supplied screws and carefully pre-tap the pilot holes, I think you've got nothing to worry about. As I've said before, this ain't the cylinder head of a Cummins diesel engine you're torquing down.

Don't forget to chamfer the rear side of driver opening, and scallop around the location of the 4 mounting screws
 

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Can't imagine why it would be a bad idea. While it's been several decades since I've owned a Yammy, and both units cited have more power than the Alpairs need, I wouldn't create the expectation of disappointment. Whatever amp you do select, be aware that break-in is real with these drivers, and you'll need more than a couple of days to be sure about anything.
 
Hello to all!


A7.3's are in the house! I'm planing a solid wood FH3 (can't get good plywood, but I have a nice mahogany :)
I do have a small/hobby/hand tool/woodworking shed, so I think I can do it properly (we'll see) Any advice is welcome...


One question, as I noticed in plans,

inside measurements are staying the same as one changes thickness of a stock...

(all makes sence...)
but, as front grows in thickness, driver is "coming" more out of a box...
How much is reasonable tolerance for this?
I'm asking this for some handtool/construction reasons...
Difference between 12 and 18mm ply is 6mm :) but is, let say, 15mm too much?!


I hope I explained this good... :/ My English is not so...
 
Well I’ve had my Frugel-Horn Mk3s for some years now with both Fostex and mark audio drivers in them and although I like the mark audio drivers better they don’t suit my line up of SETs very well . So I must opt for the Fostex fe126en enabled . These drivers do sound fantastic with the Bottlehead stereomour 45’s! Anyway I’m installing a permanent Supra baffle on the mk3’s and installing the fostex’s. I also built the xl’s which are the finest speakers i’ve heard to date in their range and price. I never even finished them or have moved them!!! Thanks for slowing down my search for a better speaker Dave and company !! It’s been a long and expensive trek after 44 years! As you will, I’ll always be searching for better , but not now . thanks again
 
Mahagony. :^)

Mahogany-FHXL.jpg


As long is there is lots of breathing space for the back of the driver you will be fine.

dave


May I ask how are fronts attached to boxes on these?
Rabbet, or some tongue and groove inside, or just glued to the rim?
What is good way to join baffle?

I'm still thinking trough a construction of my boxes, and I'm not sure if I want them with baffle in front, or flush with sides... But I'm having fun :)