| audiophile36 |
| I was told that the 126e's sound great in OB for jazz and classical music is this true? I just ordered a pair and was wondering about what type of box to use.How long does madisound take to ship? |
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| blumenco |
it is a nice driver.
the "Oh my god" range to my ear happens in the "middle" midrange zone. where the 103e has "oh my god" happening in the upper midrange frequencies and 83e being even more of a "treble" driver.
it is the least "tame" sounding (yet most dynamic) of the whizzerless standard series from fostex. it is still very nice. IMO. especially for the money...
I have tried it in a decently reinforced cardboard open baffle. next to no bass. nice and open everything else. I would recommend a box. seems to be good comments on the recommended enclosure (though complecated), I like mine in the BIBs where they permanently reside. (search BIB forum, and zilla's website) Like all the fostex banana stuff, they take a REALLY long time to break in. the bass most noticably changed on my pair.
126e in a big version BIB with a t-amp = 30-20k well balanced for 200 bucks.
madisound ships in a week.
there are also others on this forum who have far more experience with this driver and will be able to help you more perhaps.
it is a very popular driver in the u.s. the 103e seems to be correspondingly popular in japan.
Clark |
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| James D. |
Use it on an OB with a bass helper such as the Eminence Beta 15" driver... cross over at about 250 - 300Hz. Connect the drivers in series and use a cap across the Emdriver and an inductor across the 126e.
Makwe the baffle about 1300mm high and 500mm wide. Lean the baffle back by 5-8 degrees. Makes a base 450-500mm deep and make side wings that go in a straight line from the top of the baffle to the back of the base plate. Mount the Em 100-150mm off the floor and the 126 at about 750-800mm high. You will then have an OB that is flat to 40Hz and extends up as far as the fostex will allow..
James |
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| Scottmoose |
A long way.
If Nick's 167 based version of your OB I heard a few weeks back is anything to go by (crosses over about 70Hz lower I believe James) this will be an impressive system. |
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| James D. |
Yeah the 167 Nick uses goes down further than 126 will... a 127 goes a little further down but its not critical to the sound of the beastie...
I'm building a 127e based version that is about 2/3rds the size of the big beastie as its for a small flat, it uses a Beyma 8" bass helper and is flat to about 80Hz which is all my son needs :)
ciao
James |
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| Scottmoose |
| Nice. Pity we can't get Dave's phase plugs in the FE12xE series drivers. Still, can't have everything. ;) Try damping the magnet if you haven't already -makes a heck of a difference by itself. With some cone damping at strategic points the things give the Sigma a fright for about half the price. |
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| audiophile36 |
| Thank's for all the info guys.You guys seem to be the most knowledgable as one guy on A'gon suggested to use the FE126e in OB with no helper woofer and claimed the bass would be fine for jazz and classical.I don't like the idea of X-overs so I will try a double BR box for them.Dont the 127 and the 126 bth have Fs of 70hz? If so how does the 127 go deeper? Sorry this is my first expirience with Fostex drivers. |
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| Dumbass |
If someone ever writes a phrase like "bass will be fine for jazz and classical", that generally means he doesn't actually listen to jazz or classical.
I mean, large-scale symphonic is some of the most difficult material to resolve in the bass frequencies. And organ music, fuggedaboutit.
I find it a really ignorant -- but common -- idea, that people who listen to jazz and/or classical wouldn't want full spectrum sound reproduction.
[/rant] |
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| Dumbass |
| quote: | Originally posted by audiophile36
I don't like the idea of X-overs so I will try a double BR box for them. |
Ha ha, here's my second pet peeve.
If you reeeeeeeeeeeeeeally don't like crossovers, then run the 126 full-range on open baffle, and simply run the bass drivers with an active low-pass filter. That way, your 126 drivers are "pure".
If you are concerned with correct phase alignment, however, you would use an active crossover between the bass and full-range drivers.
If you are indeed concerned with correct phase alignment, furthermore, the last thing you would want to do is put the drivers in a vented cabinet, as phasing between the driver and the vent outputs is really messy. |
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| Godzilla |
http://www.zillaspeak.com/fostex127eSSB.asp
I really like the 127e in just about anything you can put it in. Its limitations are bass and an excitability that many of the mods apparently address (dammar, etc…). Recently a music lover friend was at my home listening to them and commented the sound was really warm… they can sound warm up against the wall and without a tweeter.
SI amp and Fostex 127e = great sound (regardless of price!)
Never tried them in an open baffle but expect a powered sub of choice would blend beautifully… without the sub I’d guess they’d be light in the bass.
Peace,
Godzilla |
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| Dumbass |
| quote: | Originally posted by Godzilla
I really like the 127e in just about anything you can put it in. |
Another nice thing about the 127e are the loads of plans that came out of the reference project.
Looks like the 126 could be used as replacement, with a bit of series resistance. |
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| Scottmoose |
To answer your question, the 127 doesn't 'go lower' per se. What James was refering to is the higher Q, which lends itself better to OB or box applications than the lowish Q 126, if you don't want to add extra filters.
If you've decided against OB (still a good idea if you stick a decent bass driver on, and flter it off, as James suggests) I'd build a horn over a DBR. DBR is OKish, but it'll still need baffle-step compensation, and is generally less efficient. The horns, if positioned, should not, and will allow the driver to articulate better. |
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| MJK |
| quote: | | If someone ever writes a phrase like "bass will be fine for jazz and classical", that generally means he doesn't actually listen to jazz or classical. |
I have used that statement to describe some of my ML TL speakers and I listen almost exclusively to acousitc jazz. I also attend live acoustic jazz concerts that typicaly to feature a couple of horns backed by a piano-upright bass-drum trio in an excellent acoustic venue. When the group is playing the bass and drum provides support but the dominant sound is the horns or the piano. The bass output does not shake your insides. To me this is the way recorded jazz should sound and is cosistent with the way I "voice" or balance my speaker designs.
Now when I used to listen to rock, or am subjected to the modern music my three kids insist on listening to, the bass beat is the main feature of the music. For electronic or rock music feeling the bass is part of the listening experience and I am not sure my speaker designs will do this adequately. One would probably be better using a dedicated woofer or sub for this type of performance.
I think orchestra and big band jazz falls between these two reference points. Feeling the wall of sound from the orchestra is part of the enjoyment. If I were to describe my ML TL speaker design's ability to meet this challenge I would probably use a descriptive word such as adequate. It would really depend on the quality of the recording, the volume level of playback, the room, and probably the power available from the amp.
So when somebody describes their speaker design as "bass will be fine for jazz and classical" I know exactly what they mean and have a good idea of the tradeoffs they have made. The only thing I worry about with this description is "shout", in which case the speaker design does not provide a balanced SPL output but is tilted up producing a rising response hence no bass. |
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| Bob Brines |
| quote: | Originally posted by Dumbass
If someone ever writes a phrase like "bass will be fine for jazz and classical", that generally means he doesn't actually listen to jazz or classical. |
And further more, anyone who thinks that an F3 of 60 Hz gives adequate bass has never heard real bass.
Bob |
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| Dumbass |
| quote: | Originally posted by MJK
I have used that statement to describe some of my ML TL speakers and I listen almost exclusively to acousitc jazz.
[. . .] |
Point taken. The phrase still irks me. Even in the "mildest" acoustic jazz you have all kinds of low-frequency content that adds to the music. And in classical music, well, Wagner poses the biggest challenge to my system in terms of dynamic contrast.
Also, the idea that a low-Q 4-1/2" driver in open baffle would produce enough bass for any sort of music is, well, crazy to me. |
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| audiophile36 |
| I think I'm gonna go OB and place a woofer box behind each baffle.Is there a size or particular driver that will keep up with the little Fostex? I would mount the woofer in the baffle but I only have hole cutters up to 6". |
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| Dumbass |
| quote: | Originally posted by audiophile36
I think I'm gonna go OB and place a woofer box behind each baffle.Is there a size or particular driver that will keep up with the little Fostex? I would mount the woofer in the baffle but I only have hole cutters up to 6". |
Decibel Dungeon's implementation is quite nifty:
http://myweb.tiscali.co.uk/nuukspot...dspeakers5.html |
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| MJK |
| quote: | | Even in the "mildest" acoustic jazz you have all kinds of low-frequency content that adds to the music. And in classical music, well, Wagner poses the biggest challenge to my system in terms of dynamic contrast. |
My ML TL design has measured and calculated bass output down to 40 Hz, it is very deep and tight. However, I would be kidding myself if I thought the design would move air like a 10, 12, or 15 inch dedicated woofer driver. The ML TL does a good job on acoustic jazz but does not produce that desired bass thump that can be felt and heard when playing loud rock or electronic music. That is the point I am trying to make.
| quote: | | Also, the idea that a low-Q 4-1/2" driver in open baffle would produce enough bass for any sort of music is, well, crazy to me. |
I agree completely! That is why I have 2 15" Eminence woofers per side crossed over belw 200 Hz in my OB design. |
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| audiophile36 |
Thank's for the link,
those open baffles with the clear sides look awesome! |
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| holdent |
Modeling the FE126E in MJK's excellent OB MathCad model shows the problem with the FE126E on its own in an OB. I picked a 24" x 32" OB and placed the FE126E up 18" on the centerline (the red curve below). To show how much can be improved with a woofer I added an Eminence Alpha 15A (15" woofer) next (the green dotted curve). Here's the sim including the combined FE126 and Alpha 15A (the blue curve):
This model avoids use of a xover which probably isn't advisable. The Alpha 15A has a typical woofer response peak (in this case around 2000 Hz) which will make the midrange sound very harsh for this combo. As well the FE126E has a limited Xmax so you'll want to roll it off below 100 Hz.
Note that I used a distance from the back wall of 100 in. Every OB I tried modeling performs worse the closer to the back wall its placed -- its bass falls off and there will be response irregularities (in the upper bass and lower midrange). I think I know what's happening but hope MJK will comment on this and provide a solution/workaround? |
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| blumenco |
It seems that alot of the fostex stuff benefits from being placed up against the back wall. When I look around alot of japanese sites, that is usually the way that I see things large and small actually implimented. I would credit this to the smaller rooms in most japanese homes, necessitating "space saving" systems. hence the folded horns and generally tall and slender fostex factory designs, etc.
as far as bass for classical goes, I do feel that it is most important to have it be "tuneful" bass rather than "hip hop" bass. of course, this does not take away from the stringent criterias of having immense slam when called for, immense anything really. acoustic instruments at realistic volumes are really hard to do well.
I did not understand that the driver would have a helper woofer. I would surely love to hear such a system some time.
however, I picked up this alarm clock radio from the thrift store today and happened to have a few drivers laying around....
I find that it serves extremely well for doing "background" classical music, which does not require alot of bass. the thing barely puts out .8 watts per channel before major distortion. Yes, y'all, I have decended into the realm of lower -fi. I think it sounds nice though when not distorting. and hey, I have to have SOMETHING to tote around campus to do my assigned listening on (I am a music major).
so I guess when I graduate, look for a Cain and Cain model alarm clock! |
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| MJK |
| quote: | | Note that I used a distance from the back wall of 100 in. Every OB I tried modeling performs worse the closer to the back wall its placed -- its bass falls off and there will be response irregularities (in the upper bass and lower midrange). I think I know what's happening but hope MJK will comment on this and provide a solution/workaround? |
The rear wall reflection is a problem faced by all speakers. For an OB it is worse because an equal in magnitude, but 180 deg out of phase, signal is being reflected off the rear wall and can cause cancallation of the signal from the front at specific frequencies. This is what creates the irregularities in the combined SPL response.
In reality, the large baffle probably blocks or attenuates some of this signal from arriving at the listening position so that the peaks and nulls are most likely less than calculated. I debated how to include, or not include, this reflection in the worksheets and finally decided to include the rear wall since it can be removed by the user if the distance is increased to a large value.
I am open to suggestions on how to better model this effect as long as they represent solid physics and not fudges. I am still thinking about and working on the OB worksheets so hopefully slight improvements will be developed over time. |
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| Scottmoose |
| Out of interest Martin, how does the time delay affect things? Assuming the rear reflection, even though it's nominally 180 degrees out of phase with the front, is delayed a few miliseconds, that should theoretically prevent or reduce some cancelations shouldn't it? |
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| MJK |
Scott,
Time delay is factored into the calculation. There is a time delay and also a distance attenuation of the rear wave magnitude. |
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| blumenco |
perhaps it is the stored energy/acoustic impedance created by the small gap/long path with the wall (creating more of an independant action/reaction system with the front) (as well as closer gap giving higher frequency standing waves) that gives the back wave such an audible and modelable effect on the front wave with close to wall placement of open baffle?
owing to impedance and close dimentions, close to back wall placement seems closer to an ever growingly smaller volume sealed box, but not, being too "leaky" with the front and with extreme, yet undamped, rectagular dimensions giving unpredictable energy storage...giving the unevenness?
In listening tests, I have confirmed this "weird when close to wall OB effect." it can be quite profound.
its just fudge though. sorry. just using my imagination here.
I understand that I must sound like a dimwit here at times, using little theory to back up presuppositions. using as many conditionals as possible with technical explainations. (though they should be there anyways, no matter how certain a model). eventual graduate school in acoustics should remedy this. my current school offers nothing remotely acceptably in this realm of physics, other than the independant studies within which I am already enrolled.
delves into the realm of theory of complexity, like everything in acoustics, but promises to be more approximately modelable than say, the weather in walla walla.
Clark |
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| Rudolf |
| quote: | Originally posted by Scottmoose
... how does the time delay affect things? |
Time delay is phase delay. The rear reflection is NOT nominally 180 degrees out of phase with the front. This only holds true for frequencies where the baffle to rear wall distance is 1/2 wavelength or a multitude of that.
I can´t understand why people try to keep room effects out of their simulations when they have such big influence. The baffle-to-wall distance is perfectly suited to "taylor" the speaker response around 100 Hz and below. And it can be utilised to counterbalance the first floor bounce dip (which btw has magically disappeared from holdents diagram :( )
So I really appreciate that MJK has included these reflections in his worksheets. I already try to make up my mind whether the influence of the ceiling reflection should be included too. :rolleyes:
Rudolf |
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| Dumbass |
| quote: | Originally posted by holdent
Modeling the FE126E in MJK's excellent OB MathCad model shows the problem with the FE126E on its own in an OB. I picked a 24" x 32" OB and placed the FE126E up 18" on the centerline (the red curve below). To show how much can be improved with a woofer I added an Eminence Alpha 15A (15" woofer) next (the green dotted curve). Here's the sim including the combined FE126 and Alpha 15A (the blue curve):
[snip] |
Nice sim and graph, shows why the 126 by itself in open baffle is a non-starter.
Since the 126 drops off around 200Hz anyway, I think a smaller baffle would be appropriate. Linkwitz Orion is roughly 13" wide, and the midrange driver crosses to the pair of woofers at 120Hz:
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| Scottmoose |
| quote: | Originally posted by MJK
Scott,
Time delay is factored into the calculation. There is a time delay and also a distance attenuation of the rear wave magnitude. |
Martin,
I assumed that would be the case, but I wasn't certain as I haven't been working that much on dipoles yet -too much time with horns I fear... ;) Thanks for confirming. |
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| kaybee |
here is one way to regain a bit of bass in OB.
be it 103e or whatever...
make your OB in decent size, at least
70cm x 80cm and then, after you angle it a bit
Place the Whole Darn thing
about 1-4 feet Away from an empty CORNER of room.
i presume you are not having thick towels , mattresses,
or carpets UNDER all this, or too nearby ?
experiment.
if you dont have subwoofer anxiety,
usually this is quite enuff good clean bass
from most CDs.
the rule of pi.
be good.
k |
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