Bottlehead Forum
Other Gear => Speakers => Topic started by: JamieMcC on November 24, 2014, 01:12:41 PM
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Well this is kind of a continuation from the "Suitable full range driver options for SEX" thread which popped up a little while back as I started investigate some of the different options available to try this type of speaker with my newly ordered Sex amp (I am predominantly a headphone listener) and which culminated in the purchase of some pre owned Fostex FX120's
Moving on to the present and after trying out the Sex paired with some old Mordant Short bookshelf speakers set up in a near field configuration with much better results than I had ever anticipated (In fact it is probably the best I've ever heard them sound). Building some cabinets to house the FX120 has finally made it to the top of the to do list.
So for anyone interested I will post a pic or two of building progresses, which will be slow as it is only the odd evening I can spare at the moment.
After losing way to many hours on the different forums and lots of changing my mind I've settled on the dFonkinfx enclosure for several reasons which included.
1 consistently favourable results reported for this cabinet type
2 said to work better with Sets amps and low watts
3 They have a similar footprint to my current bookshelf speakers
So pics of progress so far plans and timber.
Normally birch ply is recommended but I had a offcut of 18mm mahogany marine ply left over from a job so as it cost me nothing I'm using that instead, its way better quality than the Birch ply but don't have a clue how or if that is relevant or not to the end results.
(https://www.head-fi.org/image/id/6738487/width/900/height/900/flags/LL)
(https://www.head-fi.org/image/id/6738486/width/900/height/900/flags/LL)
Link to plans
http://p10hifi.net/FAL/downloads/dFonkenFX-0v8-map-020709.pdf
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fp10hifi.net%2Ftlinespeakers%2FFAL%2Fbox-plans%2FFonken-3D-B.gif&hash=f1fdd3b7b3d6d7912496807401221e9ec4240b20)
A completed cabinet of how it should look
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi973.photobucket.com%2Falbums%2Fae217%2Fbm1972%2FFonken%2520Prime%2FSAM_0468.jpg&hash=6c51714044cb67929799abd8af8d223711aac48d)
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Good luck with your build Jamie.
I completed Woden Valiant for use with my Paramounts. Very happy with those.
The Fonkens look beautiful. Looking forward to your build pictures!
Take care...Dave
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It would be better to have 2 or 3 horizontal braces and a top brace but otherwise they look sharp.
Something like this...
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fgr-research.com%2Fpics%2Fbox5.jpg&hash=3cc7fb4047bc9d4663f7b385fe085938876d2e40)
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It would be better to have 2 or 3 horizontal braces and a top brace but otherwise they look sharp.
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I see where you are going. I think the effect of the sandwiching of the baffles between the two vertical sides is fulfilling that particular role by creating a row of I beams which is going to make it pretty strong and resistant to flexing
The ply I have is 18mm and the distance between the cabinets internal sides and the middle offset baffle is only 70mm'ish so its going to be pretty ridged. I suspect it would probable a take fair old weight on the top 250kg for sure!
What is interesting in your example and what I have been wondering about is the radius to the holes in the centre baffle Some builds have them some builds do not? So a little more digging on which way might suit is still in order.
Cheers
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What is interesting in your example and what I have been wondering about is the radius to the holes in the centre baffle Some builds have them some builds do not? So a little more digging on which way might suit is still in order.
I believe the radius on the internal holes helps reduce turbulance within the cabinet, against the back side of the driver, as well reducing vibration within the brace/cabinet.
Another good idea is to radius the inside of the driver hole. This does reduce reflections back onto the rear of the driver.
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Thanks, chamfering the back of the driver hole I have seen mentioned in some of the Fonken build threads and had planned on doing the same.
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Hi there,
I tried the FX120 with the SEX amp and found that it needs more power than 2 watts. I felt quickly limited. It works fine with 10 watt SET.
Kind regards
Michael
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Of course what you find satisfying varies with personal taste (listening volume), room size, distance from the speakers, room hardness/softness, power and sensitivity.
But it is good to collect data. You need all the data.
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Hi there,
I tried the FX120 with the SEX amp and found that it needs more power than 2 watts. I felt quickly limited. It works fine with 10 watt SET.
Kind regards
Michael
Thanks Michael currently I have the Sex set in a near field configuration with the speakers about 3 meters apart that have a 88dB sensitivity at a Nominal impedance of 8ohms and are recommended for use with amps rated at 15 to 60 watt RMS. The Fostex are 89db (1db is not a lot unless I am wrong, I can simulate either way a little with the 1db steps on my attenuator) the current set up actually plays to loud in the room at max volume, but is just the right volume at max to listen while having a bath across the hallway. I am using the Sex's 8ohm tap.
By the way which type of enclosure did you have your FX120's in?
This also kind of raises another question about the switchable impedance settings on the Sex what happens if I run speakers like the Fostex which have a Nominal impedance of 8ohms off of a different tap could I damage the speakers?
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hi,
i currently run them in a double bass reflex enclosure http://zimmer64.files.wordpress.com/2012/10/20121010-180254.jpg
you dont damage them on the other impedance taps.
michael
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This also kind of raises another question about the switchable impedance settings on the Sex what happens if I run speakers like the Fostex which have a Nominal impedance of 8ohms off of a different tap could I damage the speakers?
This is reasonably unlikely.
The 8 Ohm tap provides a nice balance between power and damping for an 8 Ohm speaker (and distortion for that matter). If you go to the 4 Ohm tap, you will lose some power but gain more damping. Noise and distortion will also drop a bit. If you go to 16 Ohms, you'll lose damping and increase distortion.
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Thanks for the feed back guys its all very helpful.
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I really like this design. I want to build a pair of these for my Stereomour, but there is a problem.
The driver Fostex FE127en are discontinued, so no longer available.
Do you have the Fostex FE127en already?
During my search they say the FF125wk is a good follow up on the FE127en.
But this driver in the Fonken is a mismatch, so you will need a different design.
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I really like this design. I want to build a pair of these for my Stereomour, but there is a problem.
The driver Fostex FE127en are discontinued, so no longer available.
Do you have the Fostex FE127en already?
During my search they say the FF125wk is a good follow up on the FE127en.
But this driver in the Fonken is a mismatch, so you will need a different design.
Hi not 100% sure if I am reading your post correctly but I am using the Fostex FX120 the dFonkenFX enclosure is designed/tuned for that driver.
I haven't actually got much further with the build at the moment other than gluing up the baffle sections, next time I am in the shop I will try and remember take a some of pics of progress (or lack of) I have been contracting full time for a different yard so spend hardly any time at the work shop just a few minuets here and there at best of late so home projects in my workshop are on hold for a while.
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Hi not 100% sure if I am reading your post correctly but I am using the Fostex FX120 the dFonkenFX enclosure is designed/tuned for that driver.
I haven't actually got much further with the build at the moment other than gluing up the baffle sections, next time I am in the shop I will try and remember take a some of pics of progress (or lack of) I have been contracting full time for a different yard so spend hardly any time at the work shop just a few minuets here and there at best of late so home projects in my workshop are on hold for a while.
My bad! I thougt you wanted to build a Fostex Fonken, but it's a dFonkenFX :)
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Ok a few pics of where the build is at the moment
Baffles spacers glued up in one piece and will later be to cut into four sections
(https://www.head-fi.org/image/id/6823410/width/900/height/900/flags/LL)
Then cut down to size in preparation for gluing to the cabinet sides here they are dry fitted. Still need to cut the base tops fronts and backs.
(https://www.head-fi.org/image/id/6823411/width/900/height/900/flags/LL)
Decided it might be a good idea to mask up and paint the internal areas of the side baffles black as they will be a bit difficult to get at if I leave it to later on.
(https://www.head-fi.org/image/id/6823415/width/900/height/900/flags/LL)
Next step is to glue the sides and side baffle together then make a start on the other sides of the speakers enclosure.
(https://www.head-fi.org/image/id/6823416/width/900/height/900/flags/LL)
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Happy New Year all
I am hoping for some thoughts and advice on selecting some binding posts for this speaker build. I naively thought binding posts were just binding posts but on looking there is a bewildering selection of options brass, copper plated, gold plated, solid copper gold plated the list seems to go on and on.
Do you guys have any suggestions or preference for a particular materials that you have found work well when using SETs topology?
Cheers
Jamie
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I've read a lot of positive comments on Neutrik SpeakOns lately. They are not expensive, and I can't see much to object to. I am always suspiscious of the large amount of brass and the dependence on plastic inexpensive binding posts seem to have generically. I will probably use SpeakOns on my upcoming builds.
If you want simple, cheap, and impeccable connection, bring your lead wires through the back of your cab with some sealant, solder on ring tongues, and clamp similar ring tongues on your speaker cables to the speaker leads using hanger bolts or brass machine screws. That way the bolts/screws and clamping nuts are not in the path.
Skip
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I hadn't thought of doing away with the connectors altogether it sounds like a good idea to me thanks.
You can guess what is coming next
Suggestions for suitable Sexy speaker cables anyone, come on you guys must have some tried and tested favourite solutions ;D
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18 ga. solid makes for a very coherent sound that can be a bit subdued, but curbs some harshness. I've used twisted 14 ga. silver-plated, teflon insulated (multistrand) for years. Both DIY and DH Labs. The following link has an interesting variant: http://inlowsound.weebly.com/diy-speaker-cables.html
I'll be trying the ones on the Inlow link sometime this year. Acme Jr. has a good selection of silver-copper-teflon wire and good prices.
Skip
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Hi Jamie,
Check these out: http://www.electracable.com/tubeconnector.htm (http://www.electracable.com/tubeconnector.htm) . They're a super easy install and very low mass.
My personal favorite if you want both banana and spade capability is the Cardas CCBP. Made of straight billet copper and solid as a tank.
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fmeniscusaudio.com%2Fimages%2Fcopper.jpg&hash=fde15fe386e384d364dcbeae49376513a16b7311)
Regarding internal wire, I like 12 gauge silver plated copper in Teflon from Apex Jr., or if I want to splurge I get the Cardas 11.5g. Just be wary, Cardas wire that thick requires a solder pot. Another good option is the Neotech UP-OCC in Teflon.
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Hi Jamie,
Check these out: http://www.electracable.com/tubeconnector.htm (http://www.electracable.com/tubeconnector.htm) . They're a super easy install and very low mass.
My personal favorite if you want both banana and spade capability is the Cardas CCBP. Made of straight billet copper and solid as a tank.
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fmeniscusaudio.com%2Fimages%2Fcopper.jpg&hash=fde15fe386e384d364dcbeae49376513a16b7311)
Regarding internal wire, I like 12 gauge silver plated copper in Teflon from Apex Jr., or if I want to splurge I get the Cardas 11.5g. Just be wary, Cardas wire that thick requires a solder pot. Another good option is the Neotech UP-OCC in Teflon.
Hi thanks for the links I will take a look
A few pics of progress which is a little further on than these pics suggest with the centre baffle also cut and fitted but I ran out of battery juice on the camera that day.
(https://www.head-fi.org/image/id/6898517/width/900/height/900/flags/LL)
(https://www.head-fi.org/image/id/6898518/width/900/height/900/flags/LL)
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Looking good! Is that Great Stuff oozing out from the seams? :D
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The stuff oozing out is Gorilla glue it foams up a little as it cures. As the plywood had some marks and dents in it before starting it was always going to be covered (paint, vinyl, veneer still undecided on the finish) so I haven't bothered to be to neat and tidy or mask up. All the excess that has squeezed out will quickly disappear with a quick sand over with the DA.
Up to date shot.
(https://www.head-fi.org/image/id/6910048/width/900/height/900/flags/LL)
(https://www.head-fi.org/image/id/6910049/width/900/height/900/flags/LL)
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The speakers in their unfinished state are home for some testing before sealing up and starting on finishing them.
They are lot more sensitive to placement than my old bookshelfs but once in the sweet spot they float a nice detailed image. Something which I thought my old speakers did but after now hearing the Fostex its obviously they didn't.
The eagle eyed will notice the surround of the speaker are not silver their previous owner painted the surrounds black and one of the reasons I picked them up for a good price, The good news is the other speaker surround not pictured is now back to the origional silver metal finish the paint easily came off with a thumb nail I was worried the surface had been abraded to take the black paint but luckily it wasn't and the underneath is just like new.
I was excited to get them home and hooked up and forgot to take a side by side pic.
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fcdn.head-fi.org%2Fa%2Fa5%2F900x900px-LL-a5bddde6_006.jpeg&hash=b6e897609d6b8f92e63d39452bd9d3c6b0bec417)
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Very nice Jamie!
You did a great job. I have been thinking after I am done the beepre and eros I might revisit diy speakers and making a Fonken. Lookin' good!
Take care. Looking forward to hearing more....Dave
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Impressive work! Cheers!
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Why on earth would they have painted the gorgeous machined aluminum frame of the FX120 black!?!
Let us know what you think of the sound... Same driver as our Mako Stand Mounts and Floorstanders. Have been building and shipping several pairs of these lately.
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Hi Clark, the speakers have been playing most of the day and they sound quiet appealing to me. But I have nothing to really suitable to reference them against.
For the type of music I generally listen to they work well I like the vocal presentation and wasn't expecting as much bass as they are delivering this has exceeded my expectations and is sufficient for my listening needs.
I'm planning to do some experimenting with dampening/stuffing material over the next few weeks. I don't have a clue what results this will achieve but at least it will give me some reference and a better idea of the changes differing material makes. I am quiet fortunate as next door to my workshop is a small upholster who I get on well with, he always has lots of different felts, foams and suitable stuffing looking material offcuts in his wheelie bin skip and is happy for me to help myself to anything that looks suitable.
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Jamie, without being familiar with your specific cabinets I couldn't make any concrete recommendations on how much or with what to stuff them, but it sounds like you've got the time and resources to experiment so I am sure you'll find a happy medium in due time. Enjoy them... looks like you had fun!
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That looks very nice. It will be interesting to see what you choose for the final finish. I'm wondering if the magnet is tight against the divider? If done carefully and the attachment fasteners are used with captive nuts on the rear of the baffle, only the cone can move.
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A quick update I have reached a point after some experimentation with different kinds of damping materials where I am happy to call it a day and finally seal up the speaker enclosures.
It has been a surprise the difference in the stuffing medium and the density of the stuffing can make to the sound signature, after tying some felts and foams (there is a upholster and canvas maker next door to my works with a big bin off offcuts that I could rummage through.
In the end and which came as a bit of a surprise I have settled on a thin, stretchable, high fill non-woven cloth made of polyester which I know as bleed cloth and use regularly for vacuum forming composites to soak up surplus resin as its squished out under vacuum. Its also inexpensive and have rolls of the stuff to hand. Loosely packed inside it resulted in the most pleasing results to my ear. Compared to no stuffing being used the difference was easily noticeable with better bass and a clearer fuller tonally softer midrange. I have not a clue how it works but the trial and error approach has been worth it and I am over the moon with the end results.
(https://www.head-fi.org/image/id/7140104/width/900/height/900/flags/LL)
(https://www.head-fi.org/image/id/7140105/width/900/height/900/flags/LL)
In preparation to seal up the cases I settled on some solid copper, silver plated binding posts from Vintage audio ak Valab they arrived yesterday and have really impressed me with their quality the pics on the site really don't do them any justice but when held in the hand and seen up close in the flesh are very nice. So I will shortly snip off my speaker leads which at the moment have been soldered to the speaker cables and replace with these
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi.ebayimg.com%2F00%2Fs%2FNTMwWDUwMA%3D%3D%2Fz%2FXpEAAOSwQJ5USUF2%2F%24_12.JPG&hash=9390f2f891f0be88790655cf6416884a0868fc0e)
http://www.ebay.co.uk/itm/CMC-858-LU-AG-Silver-Plated-Long-Arm-Speaker-Binding-Pots-2-pairs-/281627884325?
So its start to think a bit more on how to finish the outsides of the enclosures and its not going to be veneering or anything fancy I just don't want them to be out of commission for more than a day or two as am enjoying them so much.
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Finally after nearly three years of dithering and looking at bare ply cabinets they have been finished off.
I think the FX120 in the dFonken enclosure has been a great success and its really nice to have them back in rotation while I do a bit of work on my open baffle speaker project as having two large slabs of mdf sat either side of the tv has seen waf levels at historic lows :o but holy smoke are they sounding good.
(https://cdn.head-fi.org/g/6919073_l.jpg)
(https://cdn.head-fi.org/g/9935628_l.jpg)
(https://cdn.head-fi.org/g/9935631_l.jpg)
(https://cdn.head-fi.org/g/9935630_l.jpg)
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I'm expecting to see you post one of these days about making your own carbon fiber recone for an existing driver.
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Lol I think making carbon cones is a bit above my pay grade
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I have a pair of Fostex F120as in a sealed box and love them. They are augmented by subs so don't really need any more bass reinforcement, but I've been thinking about trying a fOnken enclosure just to see what the difference is. I am eyeing the Fonken-steens from Planet10. Is that what these are?
EDIT: I took a closer look at your first post (reading is fundamental) and answered my own question. The Fonken-steen is twice the size.
One thing I noticed is that the mids and treble really cleaned up when I added a capacitor to roll them off at around 300hz, especially at higher volume. Obviously not an option if you aren't running subs, but I figured I'd mention it in case you are.
Also: can you tell me more about your OB project? I have a pair of 12" Zeniths that are destined for the same treatment if I can find the time.
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Hi the enclosure is one of these http://p10hifi.net/FAL/downloads/dFonkenFX-0v8-map-020709.pdf
The bass with the Fonken enclosure still surprises me at times ok its not anything like having a dedicated sub or some 15" bass drivers tucked away my subs are run off of a different amp and more than a few times running the FX120 of the Sex amp the bass produced has surprised me enough to make me get up out of the chair and check if the bass amp was on or not.
I have updated my OB post.
https://bottlehead.com/smf/index.php?topic=9690.0