I did just one layer of polyfil I got from a furniture maker...semi rigid sheets (1/2”) that glue in nicely, then used dense, loose cloth, in the V as it scoots down to the bottom naturally and piles up. There was a point where that pile became too dense. ‘ Backed it off a notch and found just the right loading for my room. If I move, the cloth can come out for new loading experiments. I used one “drape” of that same dense cloth in the forwardmost chamber which has only one side with the sheet polyfil. That sounded right to me.
What I mean by drape is more like a deep hammock, it spans the short distance across that part of the horn but hangs down, towards the ground about 7 inches lower than its two attaching point which are themselves 4 inches lower than the driver. I thought I could put more loose poly fill in that drape if needed...but it wasn’t needed. Everyone needs to find their own sweet spot, there are lots of variables. I offer up what worked for me.
Oh, the glue was spray glue, Gorilla makes one, so does 3M (No 77). Very sticky stuff, use gloves and great ventilation!
Cheers!
What I mean by drape is more like a deep hammock, it spans the short distance across that part of the horn but hangs down, towards the ground about 7 inches lower than its two attaching point which are themselves 4 inches lower than the driver. I thought I could put more loose poly fill in that drape if needed...but it wasn’t needed. Everyone needs to find their own sweet spot, there are lots of variables. I offer up what worked for me.
Oh, the glue was spray glue, Gorilla makes one, so does 3M (No 77). Very sticky stuff, use gloves and great ventilation!
Cheers!
I wouldn't worry too much; so long as you've got a basic amount of lagging in the throat and first part of the horn (aka the pointy bit), you won't find massive variations and unless you really cram the stuff in, which isn't recommended in most cases😉 it largely comes down to detail changes in output around the top of the horn's operating passband. The room and positioning variations are likely to have as much or more impact on behaviour.
Glad you're enjoying them! Makes it all worthwhile. 🙂
Glad you're enjoying them! Makes it all worthwhile. 🙂
Not unless you cram so much in that you actually cause the air to mass-load and deform the cone / suspension. These are back loaded bass horns; they only function over a relatively narrow BW above which they roll off, so the HF, other than the extreme condition mentioned above, is unaffected as it is direct radiation from the driver, not output from the box.
Only one more question. The counter bevel , I think bezel you call it ? What will I hear or not hear if I would do that ? Don’t like weakening the baffle around the driver area even thou I used 13 ply plywood?
I guess your 13ply is 18mm (3/4")? If so, it will still be plenty strong after flush mounting the driver and adding a chamfer on the inside.
I can't say what you'd hear, as I have done this on the two pair I've built; but my guess would be that there could be some "shout" quality added by not having as optimal air flow around the back of the speaker. I don't think you have to worry about strength.
I didn't use mine on a 10p because it was too tight a fit with the hole jig I have. Wanted to make sure a I could get the drivers out from the front if I needed.
1/ i know why they exist. 2/ once the driver bolted to the baffle they offer no real extra stiffness, 3/ they mean a deeper rebate, less meat on the backside, 4/ they create a diffraction edgenear the cone.
dave
I have 4 pairs of Mark Audio drivers and i have never heard a smidgen of shout out of them. Just terrific sound! A thinner, stronger frame is coming for the mark audio drivers so won’t much matter if mounted on top or flush mounted. Patiently waiting, lol!!!!!
Hey guys,
First time poster here AND fresh to dyi audio scene so excuse my noobishness. I had a chance to audition a pair of FHMK3 and it was love at first sound. Decided to build me a pair of FHXL for more meaty bass as I tend to listen to electronic music. That being said, I've had a few quick questions:
1. My room is fairly small (H 254cm x L 511cm x W 351cm metric; H 8"33' x L 11"52' x W 16"77' imperial). Will these work? Are there any need to adjust the amount of stuffing for this type of room?
2. I've got my eye on Emotiva A-100 amp to drive my FHXL (A11MS drivers). Will this combo work?
Again, excuse my ignorance 🙂
First time poster here AND fresh to dyi audio scene so excuse my noobishness. I had a chance to audition a pair of FHMK3 and it was love at first sound. Decided to build me a pair of FHXL for more meaty bass as I tend to listen to electronic music. That being said, I've had a few quick questions:
1. My room is fairly small (H 254cm x L 511cm x W 351cm metric; H 8"33' x L 11"52' x W 16"77' imperial). Will these work? Are there any need to adjust the amount of stuffing for this type of room?
2. I've got my eye on Emotiva A-100 amp to drive my FHXL (A11MS drivers). Will this combo work?
Again, excuse my ignorance 🙂
Pass DIY Addict
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Attaris: Welcome to DIY Audio! There are lots of great people with tons of knowledge here, so it's a GREAT place to learn. Your room is about the same size as my family room where my FHXL speakers live. This is plenty of room for them to sing - they fit rather well, not too small and not too large for this space. You can see my build by clicking the link in my signature. Your amp will be just fine for these speakers.
A final thought- DIY gets addictive, so start saving up some money for your "next" project 🙂
A final thought- DIY gets addictive, so start saving up some money for your "next" project 🙂
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Much appreciated Eric. Yeah, I figured as much that this hobby is going to stretch my finances yet again. Had a great experience with headphones before getting curious about speakers 😀
It will not cost a tenth of what it would if you walked into any HighEnd stereo shop in these United States , and you’ll have a lot of fun. If it’s building speakers or soldering a amp kit together it’s fun , yeah you’ll make mistakes, we all do , but if you choose DIY and in particular single driver speakers ( FHXL) you’ll get better sound. Ask questions , no matter how small, there’s a lot of really smart people to answer them!!!!
I fully echo this. Since I started with diy audio 3 years ago I have sneaked into audiophile world with limited finances, something I would otherwise not have been able to afford – building speakers, head amps, preamps, a power amp and lately a DAC. So, once you started there is no end, but it is such a rewarding hobby.
The FHXLs with Alpair drivers will certainly not disappoint!
It's very refreshing to see a welcoming community. Now, since I've been encouraged to ask questions - here's a few:
Do XL plans need any modifications for a pair of 11MS drivers? I figured stock ones would be fine but better safe than sorry.
I find it hard to come by any wool felt here. What other decent options do I have for damping?
Thanks!
Do XL plans need any modifications for a pair of 11MS drivers? I figured stock ones would be fine but better safe than sorry.
I find it hard to come by any wool felt here. What other decent options do I have for damping?
Thanks!