Open Baffle and Fostex FE12xE
Hey everyone,
I'm thinking of buying a pair of Fostex FE126Es or FE127Es to play around with in an open baffle design. However, other than just hunting around for cool designs and reading opinions, I've never built speakers. A full-range speaker should be easier to start with than something involving a cross-over right? Kinda a basic question, but I don't want to bite off more than I can chew.
Also, between the 126 and 127 in an open baffle I'm thinking the higher Q of the 127 is a better idea. I don't like the bumps in the higher frequencies though and I like that the 126 gets beyond 20khz. Thoughts between the two?
Thanks in advance.
Hey everyone,
I'm thinking of buying a pair of Fostex FE126Es or FE127Es to play around with in an open baffle design. However, other than just hunting around for cool designs and reading opinions, I've never built speakers. A full-range speaker should be easier to start with than something involving a cross-over right? Kinda a basic question, but I don't want to bite off more than I can chew.
Also, between the 126 and 127 in an open baffle I'm thinking the higher Q of the 127 is a better idea. I don't like the bumps in the higher frequencies though and I like that the 126 gets beyond 20khz. Thoughts between the two?
Thanks in advance.
Re: Open Baffle and Fostex FE12xE
I used a jiffy OB for my FE127's to start the "break-in" process while I built cabs for them. Dimensions for the OB were roughly based on the JE labs design. BTW, they don't sound great in OB, not much bass and won't play to a decent level.
Both of these drivers are better in a box IMHO, FE126 in a horn and FE127 in BR.
Jeff
l0gar said:
I used a jiffy OB for my FE127's to start the "break-in" process while I built cabs for them. Dimensions for the OB were roughly based on the JE labs design. BTW, they don't sound great in OB, not much bass and won't play to a decent level.
Both of these drivers are better in a box IMHO, FE126 in a horn and FE127 in BR.
Jeff
FE 127 Open Baffle
Hello Folks:
During the construction stage of the cabinets I was making for the FE127. I had the drivers mounted on an open baffle. The pupose of mounting on the baffle was to get a feel for the sound of the driver and to help break in the driver, stretch it a bit as it were. I am not sure about the correct technical term but the term that came springing to my lips was wow this really sucks. The sound was lifeless and thin. If I had not heard the drivers in a properly designed enclosure (Thanks Dave) I would have never used these drivers.
As Chris and Dave have indicated do not expect to much from the open baffle with these drivers. With a few strategically placed modifications to the drivers and a few of Dave's designs these little darlings really do shine, the OB method is for another project.
Good luck
Hello Folks:
During the construction stage of the cabinets I was making for the FE127. I had the drivers mounted on an open baffle. The pupose of mounting on the baffle was to get a feel for the sound of the driver and to help break in the driver, stretch it a bit as it were. I am not sure about the correct technical term but the term that came springing to my lips was wow this really sucks. The sound was lifeless and thin. If I had not heard the drivers in a properly designed enclosure (Thanks Dave) I would have never used these drivers.
As Chris and Dave have indicated do not expect to much from the open baffle with these drivers. With a few strategically placed modifications to the drivers and a few of Dave's designs these little darlings really do shine, the OB method is for another project.
Good luck
Re: FE 127 Open Baffle
I was going to mention ... if you want to get your feet wet with a reasoable but dirt cheap OB project, do have a look at used vintage drivers... for an expenditure of $10-$50 for drivers you can get something that can be quite musically satisfying for next to nothing -- you do need to be creative with sourcing baffles to keep the cost down.
A good example of this is the OB project below:
All of $10 for drivers. And the baffles were found on the side of the road for free... and then Scott (SCD above) turned them into OBs (he made the mistake of bringing his tools as we were cleaning up for the 2nd annual VI diyFEST).
I've had a series of drivers in them, and now we are going to install some unobtainium Korean OB FRs and auxilury 15" helper woofers and play with some of Lynn Olsen's baffle edge treatment ideas (i'm good for drilling hundreds of holes in the edges)
Choosing a set with unfasionablly high Q can give the illusion of decent bass even when the baffle/driver is hard pressed to support 100 Hz. A good example of more up-scale drivers are these Isophons (please excuse my pointing to one of my own active eBay auctions) http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280120483857 (these want a particularily slim baffle) or these Nationals http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280113550266. Q on the Nationals is maybe a bit low to give the best illusion of bottom -- they would need a wider baffle
SCD said:
I was going to mention ... if you want to get your feet wet with a reasoable but dirt cheap OB project, do have a look at used vintage drivers... for an expenditure of $10-$50 for drivers you can get something that can be quite musically satisfying for next to nothing -- you do need to be creative with sourcing baffles to keep the cost down.
A good example of this is the OB project below:
An externally hosted image should be here but it was not working when we last tested it.
All of $10 for drivers. And the baffles were found on the side of the road for free... and then Scott (SCD above) turned them into OBs (he made the mistake of bringing his tools as we were cleaning up for the 2nd annual VI diyFEST).
I've had a series of drivers in them, and now we are going to install some unobtainium Korean OB FRs and auxilury 15" helper woofers and play with some of Lynn Olsen's baffle edge treatment ideas (i'm good for drilling hundreds of holes in the edges)
Choosing a set with unfasionablly high Q can give the illusion of decent bass even when the baffle/driver is hard pressed to support 100 Hz. A good example of more up-scale drivers are these Isophons (please excuse my pointing to one of my own active eBay auctions) http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280120483857 (these want a particularily slim baffle) or these Nationals http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280113550266. Q on the Nationals is maybe a bit low to give the best illusion of bottom -- they would need a wider baffle
An externally hosted image should be here but it was not working when we last tested it.
Yes that was a surpisingly good dsounding tailgate project. It is quite amazing what you can make when you have few "Audio-nut-bars" together and all the things needed to make an instant set of speakers. A couple of quick calculations,( what is the square root of 2 again?) a pencil, a drill, a jigsaw and before you know what happened those vintage Loyds drivers never sounded so good.
If I recall they started to sound even better as the sun went down. Not sure if that was due to the temperature drop or the lubrication. It was definitely a fun afternoon.
I am definitely looking forward to this summer. Should I bring my tools again?
If I recall they started to sound even better as the sun went down. Not sure if that was due to the temperature drop or the lubrication. It was definitely a fun afternoon.
I am definitely looking forward to this summer. Should I bring my tools again?
asoprs said:
I wandered over to this thread from the Frugal horn thread (which I stumbled upon looking for class AB+ tube output topolgy [a standard PP AB amp with a floating ground tied to the plate of a class A tube IIRC])
Anyhow, I'm thinking of buying/building a Frugal horn flatpack, and I had a couple of questions about modding the FE 126e's.
I also have some sources to get the materials that no one has put forth yet.
Dammar can be had from Dick Blick, along with decoupage (puzzlecoat)
Several Varnishes
http://www.dickblick.com/categories/varnishes/#damarvarnishes
Mod podge:
http://www.dickblick.com/zz029/16/
also, Blick has 5lbs of non-hardening modeling clay for 7 bucks, which should work for the basket damping:
http://www.dickblick.com/zz332/32/
Unfortunately, Blick doesn't have thick felt.
But, a quick google search tells me the Felt People (who else?) do. I just sent out an email asking for samples. They have %100 industrial wool in 1" thickness, but they don't have prices listed. I'll post back when I hear from the Felt People.
This stuff might also work well to coat paper cones. It's very flexy PVA glue. Doesn't do what its marketed to (won't protect against stonechips) but, it might be the ticket for speaker cones.
its $25/gallon
http://www.strippablecoating.com/products/Paintshield_5720.aspx
Now, if I get this straight, we want the Decoupage to soak into the cone, right? My experience in autobody leads me to believe that thinning the stuff down 10:1 and spraying it on real thin will allow it to soak in more thoroughly. you can put an infinitely thinner coat on of anything by spraying it (provided its sprayable in the first place), but thats just my two bits.
What I don't entirely understand is whether the dammar is supposed to sit on the surface, or is it supposed to soak in also. presumably you've recommended dammar because its stiffer than the decoupage, but still flexible enough to not completely kill the frequencies it is effecting.
What I'm wondering is if dammar is really the best product, as there are a zillion different varnishes (or shellacs, lacquers, enamels for that matter). If it would be better if the spot varnish sat on the surface, shellac might be the best bet.
Thanks for the very interesting and thought provoking thread,
McGuire
Ok. Once I get one pair of 126's in good sounding order with the current techniques, I might experiment a bit and try different techniques/products.
Do you think it would be better if the puzzlecoat soaked in more, or not? (seat of the pants guess is fine my me, but you've had a lot more experience that I with modding speakers)
Also, has anyone seen 126's cheaper than $42.75 (from madisound)?
McGuire
Do you think it would be better if the puzzlecoat soaked in more, or not? (seat of the pants guess is fine my me, but you've had a lot more experience that I with modding speakers)
Also, has anyone seen 126's cheaper than $42.75 (from madisound)?
McGuire
Hi
I am just completing my MT-TL monopoles (finally) with FE127E.
See: http://www.diyaudio.com/forums/showthread.php?postid=528564#post528564
I am going to line them with felt as per thread instructions.
I am not quite sure about the stuffing though. I have two packs of Monacor MDM2 300g/m2, but I am not sure how much to put in the cabinets. Each pack contains two 630mmx330mmx35mm sheets.
Also, I have read that only two thirds (2/3) of the transmission line should be filled. Is this 2/3 of the whole cabinet (A), or the whole of the top half and 2/3 of the bottom (B)? This is my primary question. I think that I am there with the stuffing density, I am going to use a pack in each initially.
Please see photo for clarification. The photo shows a cross section of the cabinet. My port is built into the base.
I am just completing my MT-TL monopoles (finally) with FE127E.
See: http://www.diyaudio.com/forums/showthread.php?postid=528564#post528564
I am going to line them with felt as per thread instructions.
I am not quite sure about the stuffing though. I have two packs of Monacor MDM2 300g/m2, but I am not sure how much to put in the cabinets. Each pack contains two 630mmx330mmx35mm sheets.
Also, I have read that only two thirds (2/3) of the transmission line should be filled. Is this 2/3 of the whole cabinet (A), or the whole of the top half and 2/3 of the bottom (B)? This is my primary question. I think that I am there with the stuffing density, I am going to use a pack in each initially.
Please see photo for clarification. The photo shows a cross section of the cabinet. My port is built into the base.
Attachments
Harderror said:
Tom, would you mind sharing a little more detail on what you ended up with for a final setup on the Pioneer A11EC80s? I've got a quad of these sitting around and was doing some searching to get ideas. I was thinking of an MTM t-line, then a single driver bipole. Just playing around, but very interested in experienced recommendations.
Thanks!
tpremo55 said:
Wow, that was a long time ago. I haven't used those drivers in a long time. I ended up using them in the Fonken box for a long time. Then I built an MLTL for them that worked reasonably well. They are now just collecting dust though. I wouldn't build the MLTL I did either though because it was a modified TL from another design. It worked but not as well as I would have hoped. The one thing I can tell you is that this driver puts out a great deal more low end than the FE127 so any box the FE127 works in, this one will too, albeit with a bit more bass. I would opt for a Dipole if you have 4 of them. The harshness of this driver is bit of a pain to deal with. In the end, I sealed the cones (with elmers) be careful as too much will take away all high frequency. Used bluetack to damp the frames as these sing quite readily on this driver. Put a small ring of felt at the center of the driver (around the phase plug but not touching it) which calmed a couple of the peaks and of course I made and installed the phase plugs. The driver became my work system for a while (in the Fonken box) and it sounded quite good.
This driver was a fun project overall and I don't think you can go wrong messing around with it. Like I said, Dipole is probably the way to go.
Tom
Harderror said:
Thanks again Tom.
I've been more of a multi-way speaker designer than a single driver, but the fact that I have these speakers on hand has pushed me into a new area of research. I'm doing a lot of reading on mods to the cone and basket. I've made my own phase plugs in the past (for a Seas P17RCY) and have used plumbers putty on the basket. I've never coated the cone with anything...
Is there a recommended source of information with the benefits and drawbacks of the various coatings? I'm just getting setup with SoundEasy measurement (have the Behringer mic and MobilePre external card). So I may be able to trial and error some.
While I read a lot about people having high expectations for these drivers, I have noted that most of the efforts resulted in 'ho-hum' reviews. Has anyone been really happy with their design? Anyone try these to a liking in a ML-TL or other TL?
Thanks!
Todd
Member
Joined 2009
Paid Member
is it too late to ask ?
If I read it right the last post was nearly a year ago - is this thread now over with ? - it took me some time to wade through it all from start to finish and found it the best thread I've ever read on any forum.
I want to build some (eventually all 5 + sub) speakers (first time around for me) for a new HT with the emphasis on sound quality. I want to do it so that won't be as expensive as simply adding more speakers to the pair of PMC FB1's I already own. And I expect to enjoy the process along the way.
question: still not sure if there is much difference (listening) between the monopole and folded monopole ? The straight monopole looks like a good option for wall mounting.
question: the complexity of the fonken cabinet isn't a worry so the comments about it being better than the monopole caught my interest. It may be better, but is it marginal or more of a 'matter of personal taste' in terms of the sound ?
Many thanks.
If I read it right the last post was nearly a year ago - is this thread now over with ? - it took me some time to wade through it all from start to finish and found it the best thread I've ever read on any forum.
I want to build some (eventually all 5 + sub) speakers (first time around for me) for a new HT with the emphasis on sound quality. I want to do it so that won't be as expensive as simply adding more speakers to the pair of PMC FB1's I already own. And I expect to enjoy the process along the way.
question: still not sure if there is much difference (listening) between the monopole and folded monopole ? The straight monopole looks like a good option for wall mounting.
question: the complexity of the fonken cabinet isn't a worry so the comments about it being better than the monopole caught my interest. It may be better, but is it marginal or more of a 'matter of personal taste' in terms of the sound ?
Many thanks.