Remove the partition in the middle to ceate a single volume.
The bottom and top braces should be rotated so that they connect the baffle, back and vent shelfs.
I would place the centre of the 2 drivers at the 1:1.618 line.
dave
It is a BR. Put them where you want. Not a good idea to get them too close to the vents.
dave
Getting there. the back to front brace can be 2 much less extensive. As they are drawn they will impinge on the box volume.
dave
dave
Hello all
Not sure if I posted my final version of the '346' (3.46 liters) BR cabinet for the FE83, as it's undergone a lot of changes, so here it is
Not sure if I posted my final version of the '346' (3.46 liters) BR cabinet for the FE83, as it's undergone a lot of changes, so here it is
Thank you Chris, I'd forgotten. Is a 1/4" off center enough to make a difference? I changed a couple things, I'd deeply appreciate your assessment. It is here
Philips when the were still into speakers did research into tge best location of a vent in a br enclosure. They found that closest to the bass driver gives best result. What brings you to this conclusion, which is quite te opposite?
It depends on the design specifics, since 'best' is a floating point that varies with definition. Assuming reasonably pure Helmholtz behaviour, then typically you'll have max gain etc. from a close position. That was after all how the first reflex boxes were designed. Whether you actually want that is another matter of course, plus there may be Eigenmodes to consider depending on the physical dimensions of the enclosure.
i did a 3.3L BR version, a roughly 4.5" X 6.5" X 8" box, and put the driver on the 4.5" X 6.5" face, with two ports uFonken style right below the driver, and with lining/stuffing/bracing to the best i could, although now i know the port location might be too close to the driver.
anyway, it seems to have more bass then earlier versions, although not as well defined as the ufonken. its clearness is sort of between the early BR346 and the uFonken, but with more "air" than the uFonken. quite pleasant to listen to all day long. (the word clearness is used to mean that when a box sounds less clear, the effect feels to me like listening to an amp having a THD number that's not low enough).
all i've done so far are cardboard mockups.
although the FE83 shouts in nearfield listening, it does give more details, while some distance away the sound would become more balanced.
that's what i've found out so far. now some questions,
how are the two drivers to be wired up in a single volume mono box? and any special things i'd need to do to the amp driving the box? anyone?
anyway, it seems to have more bass then earlier versions, although not as well defined as the ufonken. its clearness is sort of between the early BR346 and the uFonken, but with more "air" than the uFonken. quite pleasant to listen to all day long. (the word clearness is used to mean that when a box sounds less clear, the effect feels to me like listening to an amp having a THD number that's not low enough).
all i've done so far are cardboard mockups.
although the FE83 shouts in nearfield listening, it does give more details, while some distance away the sound would become more balanced.
that's what i've found out so far. now some questions,
how are the two drivers to be wired up in a single volume mono box? and any special things i'd need to do to the amp driving the box? anyone?
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Wire the drivers parallel and make sure your amp A) can handle a 4 ohm load (prolly can) and B) sounds good doing it
You're most welcome narmex. And, yes, the FE83 has some shout in it but I think you'll find it reduced a lot by a solid cabinet, with a firm driver brace, and the clay/putty between the magnet and the frame (a handful of Duct Seal is less than three bucks at Home Despot). I'm compelled to try a full eNaBLE process on a pair, and to yank a dustcap and lash up a few different phase plug shapes on my lathe, but held back by intimidation and it being way out of my comfort zone.. Then again, I might just be being lazy, I dunno. I do have to move my fam and my shop at the end of the month...
I am beginning to really like ufonken cabinet with my FE83, initially not very much but the sound rapidly improved. I think minimal "shout" is a good word to describe the residual characteristics of the pair. Next larger cabinet will be with Duct Seal..., experiement continues.
What are the dimensions of the port(s)? I like the idea of trying this. I have 8 pairs of these speakers and am looking for a build I like.
Thanks,
Mike
oh man, i know that one. for me, it's hard trying to do anything without stability. hope you are not throwing away too much goodies that got collected over time 🙂
yes, when i settle on one version i like, i'll build a real box. i'm slow, i like to listen to the mockups for a while and not make judgement on them in a hast. also, i'm enjoying them too much, when you get them to sound good, you don't want to touch them anymore, you just want to listen to them.
be brave, enable! well, trying it on a junk driver first could be one way to start 🙂 good luck with moving!
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they are:
4.5" wide, the width of the box
3/8" tall
5.5" deep, into the interior of the box
with a spacer in the middle that's 1" wide, ufonken style
on the bottom of the front face of the box
please be aware that dave mentioned that having the ports too close to the driver may not be a good thing.
maybe you'd want to mock it up in cardboard first, in order to get a rough idea about it before wasting your time energy and resources on a real wood box.
happy building and listening!
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