Has any one han expirience with these? The reason I ask is, I built the recommended horn for the FE206ESR and I have a peak around 150hz to 200hz, that makes them hard to listen to. The drivers have over 150hrs. on them, so I think it`s the horn. Would these reflectors or stuffing the cc help reduce this peak. I sed 1/4" adheasive foam covered with wool felt behind the driver, and everything else is according to Fostex plan. They are located in the room where I`ve never had a problem before. I feel I should have built Ron`s Dallas horn despite my limited woodworking skills.....
No xo,
Although I have a different driver (108 Sigma) and different enclosure, I have similar questions: How to deal with frequency response once the things are built. So far, I have found that getting accurate measurements is far more difficult than dealing with the problem 🙂.
I did learn that near-field measurement of the horn mouth is accurate (up to 500Hz), so you might want to try that first to see exactly what you are getting from it.
I assume you have tried different room placements for the speakers and yourself. A room node might be messing up what you are hearing.
Doug
Although I have a different driver (108 Sigma) and different enclosure, I have similar questions: How to deal with frequency response once the things are built. So far, I have found that getting accurate measurements is far more difficult than dealing with the problem 🙂.
I did learn that near-field measurement of the horn mouth is accurate (up to 500Hz), so you might want to try that first to see exactly what you are getting from it.
I assume you have tried different room placements for the speakers and yourself. A room node might be messing up what you are hearing.
Doug
Thanks for the reply. I don`t think it`s a room node, the Proac Response 1sc`s with sub, and the standard version of the FE206E in recommended horn did not have a problem. In fact both measured a little dip in that range, which is probably why the peak bothers me. Have you added stuffing in the cc or any other mods. The more I listen to these, the less I like them. After spending a fair amount of time and money I`m kinda bummed. If I turn up the volume to moderate levels they get worse and worse. Compared to the other horns (FE206E) there is just something wrong. I even wonder if my glue job was bad and there are some interior panels vibrating. I sure hope not because everything is square and I have lots of clamps and put 2 100lbs weights with serious clamps when I glued the final side on. Whatever I did, I messed up somewhere......now can I fix it?
Yeah, if you don't like them, then you have to do something. That's the bottom line, I guess.
I'm sure your glue job is fine. That would be my least worry.
I did try suffing in the cc on mine, but it sucked too much life out of the midrange and messed up the soundstage. I don't recall it affecting the mid-bass, though.
You could try building an A/B switch like I use. It's really simple. The thread is about the middle of page 2 now. That way you can tweak a single speaker and compare it to the other. Start with at least 50% changes. For instance, if you want to see what effect stuffing has, take half the stuffing out of one speaker, or add 50% more, and then start narrowing it down to what helps with your problem. The switch will give you instant feedback of your changes.
I'm sorry you're going though this. I've been down that road too.
Doug
I'm sure your glue job is fine. That would be my least worry.
I did try suffing in the cc on mine, but it sucked too much life out of the midrange and messed up the soundstage. I don't recall it affecting the mid-bass, though.
You could try building an A/B switch like I use. It's really simple. The thread is about the middle of page 2 now. That way you can tweak a single speaker and compare it to the other. Start with at least 50% changes. For instance, if you want to see what effect stuffing has, take half the stuffing out of one speaker, or add 50% more, and then start narrowing it down to what helps with your problem. The switch will give you instant feedback of your changes.
I'm sorry you're going though this. I've been down that road too.
Doug
Thanks for the advice. I would not have thought about changing one and comparing it to the other. I tried to keep stuffing minimal so dynamic range would be maximal. I plan to make some changes tonite and will post as progress is made. I have to fix these, there are positives on their overall sound, but that peak needs to go down some and we`ll be alright.
NO XO,
I ran into the same problem on my 208 sigma horns. More stuffing in the cc solved the problem.
I'll be watching your progress as I intend to build the same horn for my 206esr's.
I ran into the same problem on my 208 sigma horns. More stuffing in the cc solved the problem.
I'll be watching your progress as I intend to build the same horn for my 206esr's.
Thanks for the reply. Last nite I added some polyfil to the cc and that helped, so I think we`re on the right track. I also plan to add damping to the magnet`s back and side, and put a piece of deflex at the bottom of the cc. I`ll try these one at a time so I don`t over do it. The polyfil did not hurt the dynamics and helped without any obvious negative side effects. I will post my progress.....I hope.
That's really interesting because I got the exact opposite when I put stuffing in the cc. Any amount sucked the life out of them. I guess that's why there is no definative guide to tweaking speakers 🙂
I still haven't tried damping the magnet yet, however, and you have inspired me to get off my butt and do it!
Doug
I still haven't tried damping the magnet yet, however, and you have inspired me to get off my butt and do it!
Doug
Taperwood, what kind of stuffing did you use and how much of it? I used a small amount of polyfil from Parts Express, and pulled it apart as much as I could so it was loose, and filled the cc to about the bottom of the driver. The resonance is not totally gone and it sounded better,but my Rat Shack SPL meter deteced only 1db reduction, which I presumed would be inaudible...or incorrectly measured. The more I use the meter, the happier I am with tuning by ear. As in health and fitness, the mirror tells you more than the scale.
Oh I just use the polyfill from the fabric store. I guess I'm not that picky. I've heard it's the same stuff. I tried about five different iterations of stuffing in the cc. After that I sort of gave up trying to get any improvement for now and concentrated on other things.
Ditto on the meter. It's a double-edged sword, and don't forget it's only accurate to +/- 2 dB. When I do frequency sweeps with it, it's always off by 1 or 2 dB when I return to my 1000Hz reference. I've decided the meter is good for zeroing in on what you know is wrong, but for fine tuning the ear is best.
If you stumble across anthing that tones down the mid/upper range a bit (3500-7500Hz), let me know.
Doug
Ditto on the meter. It's a double-edged sword, and don't forget it's only accurate to +/- 2 dB. When I do frequency sweeps with it, it's always off by 1 or 2 dB when I return to my 1000Hz reference. I've decided the meter is good for zeroing in on what you know is wrong, but for fine tuning the ear is best.
If you stumble across anthing that tones down the mid/upper range a bit (3500-7500Hz), let me know.
Doug
Last nite I covered the magnet with foam tape,1/4'' thick X 1 & 1/4" wide, basically weather stripping, and covered the bottom of the cc with 1" deflex. I kept the polyfil in and moved it up so most of it is directly behind the driver. I only had 45 min. to listen, and I`m very happy with the results. That sort of droning resonance is pretty much gone and now, I really like these speakers. If my opinion changes with extended listening I`ll post what I hear...at this point huge improvement.
Cool! Nice work on the cabinets. They are bigger than I imagined, looking at the plans. Are they in cherry?
Doug
Doug
FE206ESR
Hi,
No they are done in Walnut with a clear finish, and yes they are BIG. We estimate they weigh around 150# each.
Mike
Hi,
No they are done in Walnut with a clear finish, and yes they are BIG. We estimate they weigh around 150# each.
Mike
I think they are magnificient! Congratulations on what looks like a really nice job!
We picked the wood for mine: Russian wild cherry tree. I cannot wait to start!
We hired a wood worker to cut the pieces right and the whole thing will come down to about $220 canadian (wood and cuts). We did not have much of a choice as the stores did not seem to offer much help, and we are not equiped to cut this accurately. But we should be able to glue it right!😀
We picked the wood for mine: Russian wild cherry tree. I cannot wait to start!
We hired a wood worker to cut the pieces right and the whole thing will come down to about $220 canadian (wood and cuts). We did not have much of a choice as the stores did not seem to offer much help, and we are not equiped to cut this accurately. But we should be able to glue it right!😀
Here is an interesting experient that should not cost anything other than time:
1. remove all stuffing - except minimal amounts on the driver frame/magnet used to reduce reflections from bleeding through the cone. Try to make sure such material provides as little acoustic resistance as possible.
2. stuff the horn mouth with a pillow.
Note that it will attenuate the response from the lower midrange down (considerably), BUT typically something extraordinary occurs with respect to the mids and upper mids (..that is not related to simply attenuating the midbass).
1. remove all stuffing - except minimal amounts on the driver frame/magnet used to reduce reflections from bleeding through the cone. Try to make sure such material provides as little acoustic resistance as possible.
2. stuff the horn mouth with a pillow.
Note that it will attenuate the response from the lower midrange down (considerably), BUT typically something extraordinary occurs with respect to the mids and upper mids (..that is not related to simply attenuating the midbass).
ehhhh... kinda...
yeah in alot of builds stuffing the mouth kills bass. acoustic impedance is one of the prime determiners of the effect of qts on bass from a horn. you change the design by changing acoustic impedance and would need to shorten or lengthen the horn as a result.
one thing to try is to change the dimentions of the compression chamber itself. you can't make it much bigger, but you can make it smaller. that would raise the resonance frequency of the compression chamber to a point that looks like what would normally be a dip at 500 hz... the japanese seem to like bags of sand.... THIS ALSO provide mechanical damping instead of acoustic damping. mechanical keeps the rest of the horn from resonating. acoustic would kill the sound.
will this work? no idea, but I certainly see alot of CC with some sand bags, both on japanese websites and in the reccommended enclosures. I think that sometimes, especially with the special edition stuff from fostex, the sortof assume that we know what to do with them, and how to get them to our personal tastes so they give us sparing instructions. interpretation and creative implimentation brings about the very audio society we have here, no doubt.
in BLH I find that polyfill, deflex, synthetics, is geerally undesirable. instead stick with natural materials. river rock, sand, wool felt.
the wool felt I like is that used to seal doors with. found in most hardware stores.
for the magnets I glue on wool felt to just the front side of the magnet. this takes away that immediate reflection.
some can be used in the compression chamber. gradually increasing (very gradually) with alot of listening in between tweaking.
I find generally that in alot of builds with these high efficiency BLHs that people use wayyy too much damping. at least in my opinion. we do not want to use an anvil to smash an ant, as in the rest of the world of overbuilt, overengeneered, and ultimately bad sounding audio.
in 99db efficient enclosures, we get that much more sensitivity to change. a handful of stuffing gets amplified into a truckload... same as the bass is so magically acoustically reinforced. are our souls sensitive enough to weigh the small changes we must make in this realm?
also, the p-16 sound reflectors can have a profound effect on the overall sound of a horn. I think that in alot of fostex reccommended enclosures, they benifit immensely from the use of such. course, that means that you have to pay 10 bucks a hit, and fostex makes a little more money, but the p-16s are awesome because they do not kill the sound at all, the clean it. yay! implimentation matters though... ideal placement can be different from room to room.
well, hope any of that helps. these backloaded horns are strange but ultimately very very rewarding beasts. I by no means claim to have all the answers here. just suggestions from having tried everything else and simply come back to natural materials myslelf. honestly, I have heard verry few back horn setups I considered to be even remotely refined and acceptable to listen to. I am not even sure why I try sometimes. t.v. run run, ipod, loud music, next big thing, we loose our finer sensitivities. back loaded horns take a long time to tune to a room. I am working on a year now on the sound of the 166es-r horns I have. still tweaking minorly. getting more refinement daily. have patience, grasshopper.
Clark Blumenstein
yeah in alot of builds stuffing the mouth kills bass. acoustic impedance is one of the prime determiners of the effect of qts on bass from a horn. you change the design by changing acoustic impedance and would need to shorten or lengthen the horn as a result.
one thing to try is to change the dimentions of the compression chamber itself. you can't make it much bigger, but you can make it smaller. that would raise the resonance frequency of the compression chamber to a point that looks like what would normally be a dip at 500 hz... the japanese seem to like bags of sand.... THIS ALSO provide mechanical damping instead of acoustic damping. mechanical keeps the rest of the horn from resonating. acoustic would kill the sound.
will this work? no idea, but I certainly see alot of CC with some sand bags, both on japanese websites and in the reccommended enclosures. I think that sometimes, especially with the special edition stuff from fostex, the sortof assume that we know what to do with them, and how to get them to our personal tastes so they give us sparing instructions. interpretation and creative implimentation brings about the very audio society we have here, no doubt.
in BLH I find that polyfill, deflex, synthetics, is geerally undesirable. instead stick with natural materials. river rock, sand, wool felt.
the wool felt I like is that used to seal doors with. found in most hardware stores.
for the magnets I glue on wool felt to just the front side of the magnet. this takes away that immediate reflection.
some can be used in the compression chamber. gradually increasing (very gradually) with alot of listening in between tweaking.
I find generally that in alot of builds with these high efficiency BLHs that people use wayyy too much damping. at least in my opinion. we do not want to use an anvil to smash an ant, as in the rest of the world of overbuilt, overengeneered, and ultimately bad sounding audio.
in 99db efficient enclosures, we get that much more sensitivity to change. a handful of stuffing gets amplified into a truckload... same as the bass is so magically acoustically reinforced. are our souls sensitive enough to weigh the small changes we must make in this realm?
also, the p-16 sound reflectors can have a profound effect on the overall sound of a horn. I think that in alot of fostex reccommended enclosures, they benifit immensely from the use of such. course, that means that you have to pay 10 bucks a hit, and fostex makes a little more money, but the p-16s are awesome because they do not kill the sound at all, the clean it. yay! implimentation matters though... ideal placement can be different from room to room.
well, hope any of that helps. these backloaded horns are strange but ultimately very very rewarding beasts. I by no means claim to have all the answers here. just suggestions from having tried everything else and simply come back to natural materials myslelf. honestly, I have heard verry few back horn setups I considered to be even remotely refined and acceptable to listen to. I am not even sure why I try sometimes. t.v. run run, ipod, loud music, next big thing, we loose our finer sensitivities. back loaded horns take a long time to tune to a room. I am working on a year now on the sound of the 166es-r horns I have. still tweaking minorly. getting more refinement daily. have patience, grasshopper.
Clark Blumenstein
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