Frugel-Horn Mk3

I've made a mistake on a pair of frugels - basically I've made them too wide - outside measurements on the inside. They don't sound as good :)))!!

Anyway, I'm sure I'm not the only person to have ever done this, and given that I can't take them part without thrashing them, can anyone suggest a simple way of reducing the box volume to match the "correct" measurement?


Fran

Fran
 
I've made a mistake on a pair of frugels - basically I've made them too wide - outside measurements on the inside. They don't sound as good :)))!!

Anyway, I'm sure I'm not the only person to have ever done this, and given that I can't take them part without thrashing them, can anyone suggest a simple way of reducing the box volume to match the "correct" measurement?


Fran

Fran

on this design it's not a simple matter of volumetrics but rather the CSA (width) along the total path length that needs adjustment .

I've had occasion to open up a small back-loaded horn myself - it's messy as hell, but can be accomplished with a router and mortising bit once any screws are removed.
 
I know the older Buschorns were adapted to suit different drivers by varying the internal width (simply making the cabinet wider or thinner). You might try asking the designer what would be a more suitable driver and save your frugels as they are. Also, simply adjusting stuffing might help. You will get a different alignment than in the plans, but it may also work.

Back in the days of rules of thumb, it was a lot easier. You had a design for a nominal driver size and then you stuffed to satisfaction. These days, the simulations look so precise and there are dozens of radicals preaching orthodoxy. :)
 
I've made a mistake on a pair of frugels - basically I've made them too wide - outside measurements on the inside. They don't sound as good :)))!!

If you say they do not sound as good that is interesting data but are you sure that the added width is the problem? I pulled up my MathCad simulation of the Frugal-Horn Mk3 and input the extra width and the SPL response curves looked very similar. The wider version had a touch more bass SPL output but all the peaks and dips in the response curves looked the same. The enclosure should only impact the low bass output so if the problem is higher up it might be something else. Maybe try swapping the drivers between the wide and narrow FH3's too see if the drivers are a little different.

Martin
 
Moved for better sound

Moved these to a slanted ceiling corner in our bedroom.. tremendously improved lower end. Much happier....I now no longer need a lower end unit or sub to help out.. All is good.. Just please send snow for xmas...
 

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Thanks guys,

MJK: the other bit of information relates to the driver behaviour. I noticed that the alpairs in the wider cabinets had a lot more cone excursion - they almost seemed to float forwards and backwards in a slow manner - i.e. not in time with bass notes etc. In the narrower cabinets they play a lot louder with very little cone excursion. The absence of this behaviour I think is what allows them to sound better in the narrower cabinets.


Fran
 
Moved these to a slanted ceiling corner in our bedroom.. tremendously improved lower end.

that's not really surprising - coupling to slanted ceiling has dramatically increased the effective size of horn mouth

Much happier....I now no longer need a lower end unit or sub to help out.. All is good.. Just please send snow for xmas...


by all accounts you may not need to wait that long - stock up on shovels and hot cocoa mix

cheers
 
MJK: the other bit of information relates to the driver behaviour. I noticed that the alpairs in the wider cabinets had a lot more cone excursion - they almost seemed to float forwards and backwards in a slow manner - i.e. not in time with bass notes etc. In the narrower cabinets they play a lot louder with very little cone excursion. The absence of this behaviour I think is what allows them to sound better in the narrower cabinets.

That does not sound like an enclosure related problem. Sounds more like an issue with the source or the amp, remember the old turntable rumble/record warp getting to BR speaker's woofers back in the 70's.

Martin
 
Nope, not either of those - seen with a variety of sources and amps and the behaviour was not noticed with the same equipment when I used the "correct" cabinets (listening to it right now). Seen with both the older alpair 7s and the newer mk3 ones. Same improvement in sound with either alpair version too. But apart from that, there's a hardness that the bigger cabinets can have when pressed with more dense material, or older soul recordings that were often hard to begin with. The "correct" cabinets are much more forgiving to that material.


Either ways, I'm kinda sorted on this issue and am happy!! Bass weight is very good, sibilance is very natural (something I'm sensitive to), and tonal reproduction is very good. The frugels absolutely are lightening fast in their sound - electrostatic fast. This is very noticeable when compared to regular commercial box speakers. Soundstaging is good, better with suprabaffles, the soundstage is filled between the speakers, and doesn't extend outside them, and the depth is good. Placement is easy - really toe-in is the only parameter that needs careful adjustment IMHO. I've had them in big rooms, small rooms, 4W to 300W amps and they are just excellent performers. They beat the big sachiko horns by a country mile.

Fran



Ps.
I'm hoping to go semi-commercial and offer these as flat packs or built soonish, there's a few bits that have to fall into place first (not least the license!!). I'll post here when & if it happens. It may not be of much interest to anyone here due to the weight for shipping, but maybe for some in the UK or Europe.
 
frugal-phile™
Joined 2001
Paid Member
But apart from that, there's a hardness that the bigger cabinets can have when pressed with more dense material, or older soul recordings that were often hard to begin with. The "correct" cabinets are much more forgiving to that material.

It could be because the box is a little bit bigger (150/140)% or you could have a leak

dave
 
frugal-phile™
Joined 2001
Paid Member
I have a question regarding FH mk3. Do they need to be placed against a all to function well or they will work well when placed in the back drop of an absorbent wall or open space ( in the middle of the room ) ?

Jay

Depends on driver. To get the best bass out of FE126 you'll want it at least near a wall. With A7 & EL70 you can pull them out a fair bit.

dave
 
Dimension 4

I've had these drivers since 1986. They're from a company out of Dayton, Ohio. I've called a contact number on the web with no luck.... has been disconnected. They still sound amazing. I'm going to try them out in a Mk3 build. Really wish I could get some T/S specs on them. Anyone have any leads or info on them?
 

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