Frugel-Horn Mk3 Builds & Build Questions

Picked up my FH3 Flat-Pack from Bob (Big Wood Studio) this morning.
No I didn't drive all the way from Houston, I just drove up from King of Prussia.
 

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frugal-phile™
Joined 2001
Paid Member
luigiman,

The Tang Band W5-2143 would work in the FH-XL design - Scottmoose has confirmed this:

Frugel-Horn XL for Alpair 10.3/10p, Fostex FF165wk, more

OK, looks like Scott answered the question posed to him earlier today in another thread where the same query was made. Boy that guy is good.

Speaking of Dr Scott, you can see the influence of his big double mouth BVRs in these:

Liionidas-eXotic-2.jpg


Given what we know, i find these guys kinda sketchy (specs are quite inconsistent at a minimum) but some people seem to like them.

dave
 
Hey all! I have been lurking a bit here and got a flat pack delivered by Bob at Big Wood Studios. Really excited to get these built, but will take some time as school has started back up.


The flat pack came with a flush mount rebate cut in the front panel without any chamfer to the rear (no supra baffle) and I have a pair of MA Pluvia 7 PHD, and MAOP 7's to put in these.


Is there any performance to be gained by chamfering the rear of the driver cutout with the MAOP 7 or PHD 7? I have searched and searched this thread, but I only find methods of chamfering, and not the reasoning (and how to tell which drivers may or may not benefit from such a thing).



It is my understanding that chamfering the rear of the rebated driver cutout could possibly leave too little mounting support so I'm trying to figure out whether it's even something I should consider.


Thanks for your time and all the info this thread has brought! I'm super excited to get these together and singing! (drivers are already broken in :D)
 
Yes there needs to be a chamfer. Bob needs to fix that. Easy way is with a big-*** rasp.

dave

Dave, Thanks for the quick reply!

How deep and what angle is advisable for the chamfer? I have seen designs on the Woden Design website that had a 45° rear chamfer on the driver mount, but I didn't see this on any of the frugal horn plans.

Is there a general rule of reason to this that would make it easy to figure out by oneself regardless of driver?

Cheers all, and thanks for all the info on this site!
 
frugal-phile™
Joined 2001
Paid Member
Is there a general rule of reason to this that would make it easy to figure out by oneself regardless of driver?

If any of the rear of the cone sees a 90° edge that needs to be chamfered off. 45° is preferred. Given the back of the MA bezels is flat, that is where the chamfer should start. Some, particualrily stamped baskets have a bit of basket towards the back at the inside edge of the driver cutout.

You don’t want the back of the cone to be in any ore of a “tunnel” than you can avoid.

dave
 
Reima,

Please find attached an image of a chamfer I did recently. Maybe Dave can comment too.

Obviously this was done before gluing up. But it's very much possible to do one even after gluing up. Needs a rasp, sand paper, patience and some elbow grease. :)

It might be a good idea to place the driver in the cutout and mark the holes for the screws first, so that when you chamfer the inside of the cutout, you leave more material adjacent to the screws.
 

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