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After spending time on the forum with a hundred and one questions I knew it was time to get out the armchair and dust off some tools.
As of this evening I have managed to cup up a new sheet of Birch ply into little rectangles of wood. Enough for two boxes that one day should look like a pair of small Fonken's.
I found it was surprisingly difficult to cut accurately using a hand-held circular saw. Typical accuracy is only to within 1 or 2mm but given that the saw has a kerf of 2mm this isn't too awful. No doubt I'll manage to put something together with a bit of care but the final dimensions aren't going to be an exact match to the drawings. I'll try to focus on getting good contact between surfaces so that the joins are strong and air tight.
As of this evening I have managed to cup up a new sheet of Birch ply into little rectangles of wood. Enough for two boxes that one day should look like a pair of small Fonken's.
I found it was surprisingly difficult to cut accurately using a hand-held circular saw. Typical accuracy is only to within 1 or 2mm but given that the saw has a kerf of 2mm this isn't too awful. No doubt I'll manage to put something together with a bit of care but the final dimensions aren't going to be an exact match to the drawings. I'll try to focus on getting good contact between surfaces so that the joins are strong and air tight.
I caulk every joint, just in case, and if you do that then small gaps should just be cosmetic. I have not figured out how to get the final piece sealed for sure yet, since I can not get in there to caulk, I have just been lucky. No problems yet. Caulking the outside of the seam would work fine, but then that makes it so you can not stain.
Ed Robinson
Ed Robinson
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that's a good idea, I'll plan on that.
Well, one day into the project I'm learning how to use a friends router, how to make more wood dust than a continent of wood beetles. It pays to have good tools. I'm using a box of ceramic floor tiles to weigh down parts for gluing but despite the situation progress continues. I think it has a chance of working, and - it's going to be much better 2nd time around (if this pair works I have to make several more for the HT system)
Well, one day into the project I'm learning how to use a friends router, how to make more wood dust than a continent of wood beetles. It pays to have good tools. I'm using a box of ceramic floor tiles to weigh down parts for gluing but despite the situation progress continues. I think it has a chance of working, and - it's going to be much better 2nd time around (if this pair works I have to make several more for the HT system)
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planet10 said:
well, I got to play with this router and I just got carried away and made some holes. I started with some strange ideas of increasing Vb because the Fonken is quite inefficient user of space for small boxes but I don't think this saves much. Then I had an idea about a surface with odd holes in it being less likely to set up standing waves inside the box. In the end it just became a bout of madness - sometimes a man just has to make his mark.
I pulled out the wires from the back of my regular speaker and held them on the bare terminals of my new FE127 driver. I was quite surprised how much I liked the sound so at this point it would seem that any box will be good !
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yeah I don't think it's worthwhile making them holes. I think the rigidity is still good mind, give the small size of the box (Vb=6 litres) but for the front speakers I can afford taller boxes and the rigidity will be more important then.
now if I could just find some wool/felt/foam stuff around here somewhere in order to line the boxes....
now if I could just find some wool/felt/foam stuff around here somewhere in order to line the boxes....
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Well I lucked out, it turns out that there's a place in my own backyard that caters to DIY speaker guys: http://www.loudspeakers.ca/
I was able to get the terminal cups and some batting. This batting is so light I'm not sure how it has any influence or produces any damping at all. It's white medium density spun poly-ester, man-made, holds its shape very nicely, is about an inch thick but seems to me to be more air than anything else.
I was able to get the terminal cups and some batting. This batting is so light I'm not sure how it has any influence or produces any damping at all. It's white medium density spun poly-ester, man-made, holds its shape very nicely, is about an inch thick but seems to me to be more air than anything else.
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Hi,
I'm not that knowledgeable about the cups. I bought a small round one as this seems best size-wise and I wanted something that was both gold plated and that accepts both banana-plugs and can also screw down on bare wire.
I took the plunge tonight and set up my hand-held circular saw for the 45 degree corner cut. I had quite some trouble. I had to duct tape the blade guard out of the way - not something you could ever recommend (and there's a little groove in my work bench to remind me). I had to nail a strip of wood on the front of the box to guide the foot plate or it simply wandered off the corner. The saw didn't half groan through this job!
Still, it's done and the boxes survived ! I wasn't patient enough to put the lids on until I'd satisfied myself that the batten would do, so I'll hand finish the chamfer on those before I glue them in and then do a final sand to ensure the chamfer lines up nicely.
I do like this Onken design, it's been a lot of fun to build so far, more than I had expected. Unless they sound like cats fighting in an alley I'll most likely be happy with 'em.
I'm not that knowledgeable about the cups. I bought a small round one as this seems best size-wise and I wanted something that was both gold plated and that accepts both banana-plugs and can also screw down on bare wire.
I took the plunge tonight and set up my hand-held circular saw for the 45 degree corner cut. I had quite some trouble. I had to duct tape the blade guard out of the way - not something you could ever recommend (and there's a little groove in my work bench to remind me). I had to nail a strip of wood on the front of the box to guide the foot plate or it simply wandered off the corner. The saw didn't half groan through this job!
Still, it's done and the boxes survived ! I wasn't patient enough to put the lids on until I'd satisfied myself that the batten would do, so I'll hand finish the chamfer on those before I glue them in and then do a final sand to ensure the chamfer lines up nicely.
I do like this Onken design, it's been a lot of fun to build so far, more than I had expected. Unless they sound like cats fighting in an alley I'll most likely be happy with 'em.
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Bigun said:
The little ones are goof (smaller hole cut into the box, but the solid ones with gold are to be avoided...
You got these ones? (everyone sells these)
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These are preferred (but a lot of people think they look cheesy)
An externally hosted image should be here but it was not working when we last tested it.
dave
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Well, a pair of new Fonkens are born.
The terminal cups are held in with duct-tape for now and the box isn't sealed (I will caulk it on the outside prior to finishing).
Compared with my floor-standing PMC FB1s you clearly notice something is missing. It's the extended LF. The bass is fine and it's tight, but of course it can't go as deep. No complaints. I think the tuning is close to where it should be, I thought I heard a bit of 'boom' but then a couple of tight drums dispels any doubt.
Imaging is amazing, I can't easily do an A-B with my PMCs but the Fonkens are at least as good, if not better.
There is something not yet right though. The high's are a bit harsh, slightly confused, a 'fuzzy' edge to them. It ain't smooth enough. Male voices are superb, female voices suffer at the high end from the 'fuzzy' edge.
Of course the drivers have had no time to break in yet (not sure how much change to expect after break-in) and I strongly suspect that there isn't enough damping on the inside-back of the box directly behind the driver (which I could readily fix if I get convinced of the need).
It's quite a record for me, entering a new 'hobby', contemplating and finalizing a design for what - maybe 2 weeks at most (accelerated by planet10) and then building it to this point in 5 days.
It's looking dangerously like this might result in more Fonken offspring
The terminal cups are held in with duct-tape for now and the box isn't sealed (I will caulk it on the outside prior to finishing).
Compared with my floor-standing PMC FB1s you clearly notice something is missing. It's the extended LF. The bass is fine and it's tight, but of course it can't go as deep. No complaints. I think the tuning is close to where it should be, I thought I heard a bit of 'boom' but then a couple of tight drums dispels any doubt.
Imaging is amazing, I can't easily do an A-B with my PMCs but the Fonkens are at least as good, if not better.
There is something not yet right though. The high's are a bit harsh, slightly confused, a 'fuzzy' edge to them. It ain't smooth enough. Male voices are superb, female voices suffer at the high end from the 'fuzzy' edge.
Of course the drivers have had no time to break in yet (not sure how much change to expect after break-in) and I strongly suspect that there isn't enough damping on the inside-back of the box directly behind the driver (which I could readily fix if I get convinced of the need).
It's quite a record for me, entering a new 'hobby', contemplating and finalizing a design for what - maybe 2 weeks at most (accelerated by planet10) and then building it to this point in 5 days.
It's looking dangerously like this might result in more Fonken offspring
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Bigun said:
With break-in the bottom should improve, and the top end should smooth a bit. The issues caused by the 7 k peak and the cone self-noise will not completely dissappear. The pre-treatment that i do mostly cures that. The rest of my regimine adds a couple layers of icing, and some ice cream & whip cream.
dave
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I'll give it a week or so, seal the box and finish it off then listen some more. I have read about your treatments but hadn't thought of putting my hand to the cone yet - but now that I've got this far I may just as well put that on the list of things to have a go at.
And now that you mention it, those cones have a kind of French Vanilla colouring...
And now that you mention it, those cones have a kind of French Vanilla colouring...
Bigun said:
Gareth - if you hadn't had the opportunity to fully break the drivers in (as in 200-300hrs ) before installation, I'd suggest holding off on playing with stuffing of the box.
The current issues that you're having with the upper midrange with bone stock drivers will be somewhat ameliorated by the break-in, but at the very least Dave's (pre-EnABL) "tri-foil" pattern/puzzle coat treatment would be highly recommended. But, for the full-meal deal, try the EnABL.
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