Dave - Honest question, I mean no offense, but how exactly is the Emken (or the Onken) an aperiodic design? The definitive thing about them seems to be that they are a "leaky" sealed enclosure... And the Em-ken seems to be more of a ported design, or even ml-tl.. just one of those mysteries of life? 🙂
If it sounds good, I guess it doesn't matter!
If the Em-ken design likes higher Q, maybe there's a Mega Emken in the future with that Fane 15" FR... 😉
What programs could I sim the Em-ken with, if any?
And what program will give excursion values for freq/dB?
If it sounds good, I guess it doesn't matter!
If the Em-ken design likes higher Q, maybe there's a Mega Emken in the future with that Fane 15" FR... 😉
What programs could I sim the Em-ken with, if any?
And what program will give excursion values for freq/dB?
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They are not aperiodic, they are a BR pushed towards being aperiodic. Resistance provided by the high ratio vents. With the alignment used you still get bass but they are less prone to losing alignment as the T/S parameters change with the dynamics of the music and how high you have the levels.
You can push them further towards aperiodic by inserting open cel foam blocks into the vents. With enuff or enuff density you will get at least close to full aperiodic. At the loss of bass extension.
dave
Ah, okay thank you - that actually makes sense. The 12lta Em-ken then I'm assuming fits the 12lta only, aka the Fane 250TC t/s parameters are too different to load it right? Or it's just an unknown?
I need to find a frequency plot for the 12lta in the Em-ken, and figure out where the helper woofer needs to come in and pick up the slack. I was planning to run the FR driver full range (naturally), and bring in the woofer low, but high enough to lend more "punch" to the FR. All about, that "punch", I know, I know... 😉
<And yet to be figured out, a budget means of crossing or at least blocking the highs to the woofer, as well as potentially crossing or at least blocking the lows to a super tweeter.... Possibly a LF highpass for the woofer needed to keep it from self destructing during movies/HT use? Need to be able to sim excursion I think.>
Any thoughts on what to use for the helper woofer? I see a lot of folks use the Eminence alpha 15 (97 db) or delta 15 (96 db), and also that Goldwood gw-1858 18" woofer (94 db). Also Dayton pa-460-8 (97 db). I'm still on a budget, so nothing $$$ unfortunately. Probably best if the woofer has an efficiency close to the FR driver, so upper 90's. Not sure if there's any reason to use a "pro" woofer? No consideration (yet) given to what type of enclosure the woofer should be in, though if it's on the bottom of a stack(under the FR box), compact is good. Requirements are mostly punch-punch, very little (occasional) boom boom required. Transitions/performance requirements range from Pink Floyd to Daft Punk to Dave Matthews to Bach...
I need to find a frequency plot for the 12lta in the Em-ken, and figure out where the helper woofer needs to come in and pick up the slack. I was planning to run the FR driver full range (naturally), and bring in the woofer low, but high enough to lend more "punch" to the FR. All about, that "punch", I know, I know... 😉
<And yet to be figured out, a budget means of crossing or at least blocking the highs to the woofer, as well as potentially crossing or at least blocking the lows to a super tweeter.... Possibly a LF highpass for the woofer needed to keep it from self destructing during movies/HT use? Need to be able to sim excursion I think.>
Any thoughts on what to use for the helper woofer? I see a lot of folks use the Eminence alpha 15 (97 db) or delta 15 (96 db), and also that Goldwood gw-1858 18" woofer (94 db). Also Dayton pa-460-8 (97 db). I'm still on a budget, so nothing $$$ unfortunately. Probably best if the woofer has an efficiency close to the FR driver, so upper 90's. Not sure if there's any reason to use a "pro" woofer? No consideration (yet) given to what type of enclosure the woofer should be in, though if it's on the bottom of a stack(under the FR box), compact is good. Requirements are mostly punch-punch, very little (occasional) boom boom required. Transitions/performance requirements range from Pink Floyd to Daft Punk to Dave Matthews to Bach...
Unknown but unlikely. miniOnken alignments are pretty driver specific.
There are a few overlaps but not many so far.
dave
Side Note:
Does anyone try to fix higher frequency beaming issues w/ any sort of acoustic lensing?
Karlson has his K-aperture, and JBL had some interesting waveguides (not sure they'd actually be termed waveguides), like this:
http://www.jblpro.com/pub/obsolete/Acoustic_Lens_Family1.pdf
I wondered if this would be a way to widen the sweet spot, adding something like this to the front of a BR or sealed (or whatever) enclosure... (though I'm sure the use of such devices have their own negative side effects)
Back on subject:
Thinking more about the enclosure to mount the full range driver in, I suddenly had a thought - does it even really matter? BR (and basically all other enclosures) simply give better low end extension, and they have minimal if any effect on the mids/highs coming off the front of the driver (perhaps the Karlson design is the exception)... <Please correct me if I'm wrong here, I know there's more to it than putting it this simply>
The bass in this case will be handled by a helper woofer, probably up to 100-150 hz where it crosses to the FR right? So now I'm not so sure it matters... sealed, mltl, blh, br... all about the same*** after 100-150 hz right?
***Of course this is dependent on the particular design, no doubt a box could be made to influence higher mid-bass frequencies above the crossover point and thus even with the helper woofer could sound quite different depending on the box design...
Does anyone try to fix higher frequency beaming issues w/ any sort of acoustic lensing?
Karlson has his K-aperture, and JBL had some interesting waveguides (not sure they'd actually be termed waveguides), like this:
http://www.jblpro.com/pub/obsolete/Acoustic_Lens_Family1.pdf
I wondered if this would be a way to widen the sweet spot, adding something like this to the front of a BR or sealed (or whatever) enclosure... (though I'm sure the use of such devices have their own negative side effects)
Back on subject:
Thinking more about the enclosure to mount the full range driver in, I suddenly had a thought - does it even really matter? BR (and basically all other enclosures) simply give better low end extension, and they have minimal if any effect on the mids/highs coming off the front of the driver (perhaps the Karlson design is the exception)... <Please correct me if I'm wrong here, I know there's more to it than putting it this simply>
The bass in this case will be handled by a helper woofer, probably up to 100-150 hz where it crosses to the FR right? So now I'm not so sure it matters... sealed, mltl, blh, br... all about the same*** after 100-150 hz right?
***Of course this is dependent on the particular design, no doubt a box could be made to influence higher mid-bass frequencies above the crossover point and thus even with the helper woofer could sound quite different depending on the box design...
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Does anyone try to fix higher frequency beaming issues w/ any sort of acoustic lensing?
Phase plugs are needed in most whizzer cone drivers.
It matters, but used as a midTweeter one can consider sealed or aperiodically damped midTL.
With a sealed box, one can target a Q=0.707 and then use the natural 2nd order rolloff as part of the XO. An additional 2 orders can be added to match a 4th ordr rolloff of the woofers. For the 12LTA — bs\ased on sim — would be 130-150 litre box and an XO just above 80 Hz.
dave
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I was planning on phase plugs - I meant going a little more crazy and using some sort of waveguide like those JBL bits I linked, or incorporating a Karlson K-aperture into the box design (so sort of a sealed enclosure but with a "veiled hood" coming around and nearly forming a second chamber in front of the driver). Probably academic as I'm not sure how you'd sim it.
How does it matter? I'm not sure I understand, think I'm missing something here...
Using the FR driver down to 80 hz would still keep the FR magic but limit excursion to keep things from getting muddy when there is simultaneous deeper bass and mids/treble...
Large helper woofer would have bigger Sd than the FR, so will move more air and thus be more "punchy" (?) according to what I've read here, so maybe it needs to be crossed higher at more like 175hz, given GM's "punch" range?
Feels like I'm stuck and can't have it both ways...
Also, still more tempted to use the Fane 12-250tc over the 12lta just because of its top end freq response - might not need that supertweeter in this case. But reading elsewhere, the measured Qts of the Fane is more like .91?! That's nuts! So maybe not worth trying?
http://www.prodance.cz/data/attachments/Sovereign_12_250TC.pdf
Here's the Fane 250tc discussion where that measured freq response was linked from.
New 12" Full-Range: Fane 12-250TC
New 12" Full-Range: Fane 12-250TC
The enclosure matters and doesn't leave the midrange and treble unaffected. The loudspeaker unit is a part of the loudspeaker system. The system behaves differently if it is constructed differently, if there are different physical phenomena happening. A driver on an open baffle is moving in free air, but in a sealed box it is pushing and pulling into that volume etc. So when they say that a driver does well in a certain type of enclosure, tuned to a certain alignment, what they really mean is that this gives a system that works well mechanically. It pays off in optimal sound.
I do tend to re-use drivers in different projects and it is very clear that the enclosure makes a difference to performance. It's like finding the right pressure for the tires of your car, or something like that. My advice is always BiB at the moment, I am having so much fun with mine.
I do tend to re-use drivers in different projects and it is very clear that the enclosure makes a difference to performance. It's like finding the right pressure for the tires of your car, or something like that. My advice is always BiB at the moment, I am having so much fun with mine.
Ivo - I agree, I should have been more clear in the context of my statement; I meant the mids/highs didn't seem to change much in the context of looking at frequency plots in WinISD while changing the box type and size between sealed/vented. Air in the tires is probably a fair comparison - depends on the vehicle, terrain, and speed. (aka Speaker driver, type of music, frequency). BIB is a bit large with the 12" FR, have you tried it? It's about as big as I could possibly permit in the living room... But not sure how it'd fair in a shoot-out, 12" BIB versus 12" sealed/ported/etc w/ 15 or 18" sealed/ported/etc helper woofer... No doubt the bib sound is impressive given that it's only a single full range driver per channel; but compared to the low end grunt of a 15" or 18" woofer?
I meant to comment more on this but had lost my train of thought earlier... I like the idea of using the natural roll off vs using electronics, but on the high freq rolloff of the woofer, or low freq rolloff of the FR? Or Both, if they could be made to align..?
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I had a pioneer b20 that sounded better in a .577 qtc than .707
I think it has to do with less back pressure on the cone or simply more box, i couldn't tell you why.
I think open baffle folks are onto a similar thing (no back pressure).
I think it has to do with less back pressure on the cone or simply more box, i couldn't tell you why.
I think open baffle folks are onto a similar thing (no back pressure).
More of a fantasy than an idea, and why, for what reason? Use both to achieve alignment. I've heard some people on this forum advocate using a fullrange and woofer both run without any crossover, again why? I don't think they can be interested in anything even remotely hi-fi
Right all basic T/S box calculators are blended in/done by the effective upper mass corner [fhm = 2*Fs/Qts'], so at best it will also show any rising impedance due to its inductance and IIRC it has to be defaulted to 'on' in WinISD 0.7 [the version you should be using]. Better to switch to at least Hornresp or LA's TL/horn and of course the AkAbak program.
Qts' = Qts + any added series resistance: mh-audio.nl - Home
GM
Qts' = Qts + any added series resistance: mh-audio.nl - Home
GM
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I'd probably try open baffle if it seemed like it would work jammed up against a wall or in a corner.. but alas, its a living room not a listening room 🙁
Just a thought, wasn't sure if drivers could even be chosen to work this way. Some reading had led me to be concerned about things being out of phase using crossovers. Probably a larger fear is just buying more and more stuff to try and get the sound right.. only to give up if I can't make it work, and buy a prepackaged kit or something similar.. hoping to do it once, and do it right.
Oh... this I did not realize. Thanks, suddenly things make more sense!
Thanks GM, this has been more of a learning curve than anticipated. Not attempting to become an acoustic engineer overnight, but would be rather disappointed if I make something that doesn't sound good! WinISD version 0.44, so apparently I've got an earlier version.. I'll have to look for version 7. I have HornResp but haven't played with it as much as WinISD as it seemed less intuitive. I need to spend more time playing with it.
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Unlikely to happen. It is addictive. No matter how well the initial implentation is the urge to try something different will lead to more…
dave
Was in a hurry, actually 0.7.0.950 now: WinISD - WinISD 0.7.0.900 available for download | Facebook
Anybody know about Leonard Audio or where the TL software, manual is archived? My links are dead, ditto Google's!
GM
Anybody know about Leonard Audio or where the TL software, manual is archived? My links are dead, ditto Google's!
GM
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Dunno, but last Wayback Machine archive seems to have been last year & with a bit of jiggling (might just be my rubbish ISP acting the goat as usual) it downloaded: Download | Leonard Audio
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