Hi lejaybo, I have fiddled with using 2 FE126E's per cab and the advantage I found is that you can re-inforce the bass at the point where it dips due to baffle step. But this isn't deep bass -- it's more like upper bass / lower midrange. Also, using the second driver in this fashion requires an inductor of a specific value on the second driver (a BSC calculator comes in handy). Alternatively, you can just let the second driver run full range but it splashes a lot of HF around the room -- some people like it.
So far, I've tried sealed, aperiodic, BR and horn, all with and without subs. I just bought a cheapo $11 woofer with (supposed) Fs of 28Hz to try next. If you haven't bought your drivers yet, the FE127E is easier to work with (easier to tame). A BiB is a logical choice when bass is mentioned, though I haven't yet built the BiB for this driver.
Have you checked out the bipole cabs for the "diyAudio reference" project? It's a range of FE127E/FE126E cabs: http://www.planet10-hifi.com/boxes-fostex.html#diyRef
Also, while this is not quite what you're looking for, check out this bipole design for the FE127E for some theory on bipole: http://diyaudioprojects.com/Speakers/FE127E_SB/FE127E_SB.htm
So far, I've tried sealed, aperiodic, BR and horn, all with and without subs. I just bought a cheapo $11 woofer with (supposed) Fs of 28Hz to try next. If you haven't bought your drivers yet, the FE127E is easier to work with (easier to tame). A BiB is a logical choice when bass is mentioned, though I haven't yet built the BiB for this driver.
Have you checked out the bipole cabs for the "diyAudio reference" project? It's a range of FE127E/FE126E cabs: http://www.planet10-hifi.com/boxes-fostex.html#diyRef
Also, while this is not quite what you're looking for, check out this bipole design for the FE127E for some theory on bipole: http://diyaudioprojects.com/Speakers/FE127E_SB/FE127E_SB.htm
lejaybo said:
That is called a FAST system. They are becoming more popular. You'll need to bi-amp or have very efficient woofer(s) to do a passive design without padding down the FE126 (and if you are doing tat you might as wll use FE127/103/83/FF85
For the FE126e the simpliest cabs that will get you decent bass are a metronome or a BIB... otherwise you should be looking at a horn
For 2 FE126 you best bet is likely a bi-polar Metronome.
dave
lejaybo said:
From the front the FE126 & FE127 are the same... as Vallyman says there is a large difference when it comes to boxes. The FE127 is also a bit smoother, but perhaps with a bit less jump. The FE126 benefits even more from a higher output impedance amp than the FE127, so in that respect would be more suited to your amps (that last bit is mostly about bass -- not a consideration with a FAST.
The most prominent FAST system lately have been variation son the MJK open baffle, We have recently completed Tysen (bit not had an opportunity to talk about it much). Any system that uses a full range as a mid tweeter with a helper woofer(s) is a FAST. XO is typically in the 100-400 Hz range,
dave
I ran something like that.
I now run a dual 4" bamboo in a single box that naturally rolls at 200hz (way higher due to baffle step).
I also use a 12" with an 80hz fmod for bass.
A higher freq f-mod would help bass more.
http://viewmorepics.myspace.com/ind...ID=180422547&albumID=1552714&imageID=24436495
This works well at 1 listening spot.
You have to be exactly the same distance to both drivers.
When my wife sprawls on the other couch, she is lower and closer to the speaker. I have highs where I am, she does not.
I noticed the sound was good at 1 end of my couch but worse at the other end.
Last week, I places a cd under the middle of the bottom of the cabinet and my highs greatly improved. And it sounds better at the bad end of the couch.
I sit about 12' away from the speaker.
Soon I'll be using 1 driver in open baffle.
I abandoned the 4 driver focused array project.
2 drivers = less excursion = cleaner sound.
but crossing to a woofer near 200hz kills 3 birds with 1 stone.
less excursion.
cleaner voice.
and larger listening spot (vertically).
Crossing at 200hz works better than running 2 4" drivers.
I see why baffle step works well given the drivers arn't too expensive. I didn't see that as an option for the $50 tang band bamboo drivers.
But if you are a transparancy guy (like me), you will not find an active crossover that is as clean as hooking to the speakers without it. You lose detail big time through active crossover, especially at my low listening levels.
Norman
I now run a dual 4" bamboo in a single box that naturally rolls at 200hz (way higher due to baffle step).
I also use a 12" with an 80hz fmod for bass.
A higher freq f-mod would help bass more.
http://viewmorepics.myspace.com/ind...ID=180422547&albumID=1552714&imageID=24436495
This works well at 1 listening spot.
You have to be exactly the same distance to both drivers.
When my wife sprawls on the other couch, she is lower and closer to the speaker. I have highs where I am, she does not.
I noticed the sound was good at 1 end of my couch but worse at the other end.
Last week, I places a cd under the middle of the bottom of the cabinet and my highs greatly improved. And it sounds better at the bad end of the couch.
I sit about 12' away from the speaker.
Soon I'll be using 1 driver in open baffle.
I abandoned the 4 driver focused array project.
2 drivers = less excursion = cleaner sound.
but crossing to a woofer near 200hz kills 3 birds with 1 stone.
less excursion.
cleaner voice.
and larger listening spot (vertically).
Crossing at 200hz works better than running 2 4" drivers.
I see why baffle step works well given the drivers arn't too expensive. I didn't see that as an option for the $50 tang band bamboo drivers.
But if you are a transparancy guy (like me), you will not find an active crossover that is as clean as hooking to the speakers without it. You lose detail big time through active crossover, especially at my low listening levels.
Norman
well.................
Now the dual driver box is too deep (21") and is swapped out for a mtm with lineaum tweet (not time aligned, ewwwwwwww, but f3 is closer to 80hz). Maybe I'll hook up the bamboos later tonight.
I should have ran an extra set of binding posts, but worst case scnario, I figured I'd run them like a von schweikert.
http://www.vonschweikert.com/media/images/opening2.jpg
The dual driver von schweikert has cleaner midrange than their design with a single mid (imagine that with 2 drivers).
Bipole could have been an option also.
An open backed box is hopefully in the works as soon as I can talk to my carpenter. It's 2' tall, 2' wide, and 10" deep. Driver is on the bottom edge and 9.2" from the right edge. It will be sitting on a dual 15 bass module. Lots of differing distances from the driver to back side will make for lack of suckouts present on an open baffle where a driver is mounted exactly in the center.
With the Feq of the open baffle and the large front baffle, it will make it to 200hz easy.
Best mids I ever had was a tang band w3-871s on an open baffle.
But the dual bamboo design, it was my first build on my path.
With the loudness button on, it fills in the mids nicely.
Without it, there is a midrange suckout and zero bass.
That's what you get with a box front baffle 8" wide and 13" tall and 21" deep. I could fix all this with +3db at 500hz and +6db from 250hz down on a 10 band equalizer.
Run wide open, it wanders away below 700hz (baffle step corner). Then sealed box rollof below 200hz (qtc .45 to simulate open baffle lack of back pressure, f3=178hz).
In the very narrow vertical sweet spot, it is wonderfull (with loudness on and the 12" for bass). Without all this help, it sounds horrible.
Remember 12' away, placing a cd under the middle of the bottom made a big difference with a dual 4" (5" frame) drivers setup.
Just like the omega minuet that was an inspiration.
http://www.dagogo.com/images/SG-NYC-Omega-Minuet-front.jpg
Norman
Now the dual driver box is too deep (21") and is swapped out for a mtm with lineaum tweet (not time aligned, ewwwwwwww, but f3 is closer to 80hz). Maybe I'll hook up the bamboos later tonight.
I should have ran an extra set of binding posts, but worst case scnario, I figured I'd run them like a von schweikert.
http://www.vonschweikert.com/media/images/opening2.jpg
The dual driver von schweikert has cleaner midrange than their design with a single mid (imagine that with 2 drivers).
Bipole could have been an option also.
An open backed box is hopefully in the works as soon as I can talk to my carpenter. It's 2' tall, 2' wide, and 10" deep. Driver is on the bottom edge and 9.2" from the right edge. It will be sitting on a dual 15 bass module. Lots of differing distances from the driver to back side will make for lack of suckouts present on an open baffle where a driver is mounted exactly in the center.
With the Feq of the open baffle and the large front baffle, it will make it to 200hz easy.
Best mids I ever had was a tang band w3-871s on an open baffle.
But the dual bamboo design, it was my first build on my path.
With the loudness button on, it fills in the mids nicely.
Without it, there is a midrange suckout and zero bass.
That's what you get with a box front baffle 8" wide and 13" tall and 21" deep. I could fix all this with +3db at 500hz and +6db from 250hz down on a 10 band equalizer.
Run wide open, it wanders away below 700hz (baffle step corner). Then sealed box rollof below 200hz (qtc .45 to simulate open baffle lack of back pressure, f3=178hz).
In the very narrow vertical sweet spot, it is wonderfull (with loudness on and the 12" for bass). Without all this help, it sounds horrible.
Remember 12' away, placing a cd under the middle of the bottom made a big difference with a dual 4" (5" frame) drivers setup.
Just like the omega minuet that was an inspiration.
http://www.dagogo.com/images/SG-NYC-Omega-Minuet-front.jpg
Norman
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