tinitus said:
Yes, there was no attempt to import the impulse response at a real world spl level, since it is fo a crossover design and all the drivers for the design were measured under these settings.
MisterTwister said:
Here is the impedance that I measured that went with the FR measurement that Augerpro posted. This was an in box measurement.
John, thank you for explanation. I am aware that low inductance is very important. your woofers' impedance curve looks as impressive as it's FR.
but still, ushers' 8945p impedance curve is just as good.
I guess your woofers have better cone geometry and surround.
So if you listen to them full range and loud, do they still sound not strained?
but still, ushers' 8945p impedance curve is just as good.
I guess your woofers have better cone geometry and surround.
So if you listen to them full range and loud, do they still sound not strained?
The Supravox 285 GMF could be an option. But I don´t know whether Supravoxes are currently distributed in the US.
What I believe can be generalized: If you get well across the breakup region you get as far as the cone mass allows. So an uncompromized 12"+1" solution will "abuse" a 12" that could do much more.
What I believe can be generalized: If you get well across the breakup region you get as far as the cone mass allows. So an uncompromized 12"+1" solution will "abuse" a 12" that could do much more.
John, I really like your driver and still considering to buy a pair fore midrange duty...but waiting to see your new midrange devellopment
BUT, from measurements you show it seems that FR is 5db down from around 400hz and downwards...and down again from 800hz and upwards
Or in other words...slight peaking between 400-800hz
Is that due to a measurement error or ? any comments ?
BUT, from measurements you show it seems that FR is 5db down from around 400hz and downwards...and down again from 800hz and upwards
Or in other words...slight peaking between 400-800hz
Is that due to a measurement error or ? any comments ?
useful plots/designs for a number of 12" here http://www.prodance.cz/protokoly.php?AnchorID=67&Lng=EN
since this is linked to the search for a good waveguide, this "megaton a9090" looks like it has a good profile, but haven't been able to get hard info on it.
http://translate.google.com/transla...speakers-de250.php&hl=en&ie=UTF-8&sl=cs&tl=en
since this is linked to the search for a good waveguide, this "megaton a9090" looks like it has a good profile, but haven't been able to get hard info on it.
http://translate.google.com/transla...speakers-de250.php&hl=en&ie=UTF-8&sl=cs&tl=en
well, scratch that. The response looks decent enough http://www.megaton.cz/2005/uploads/zvukovody/megaton_A9090_de25.pdf
but they look like something out of the stone age http://www.megaton.cz/ under " 1" zvukovody "
but they look like something out of the stone age http://www.megaton.cz/ under " 1" zvukovody "
Nice find.
I visit that prodance.cz site every day, but I hadn't looked up that waveguide.
On the other hand, it doesn't go anywhere near low enough for anything except maybe a 6" midrange. You'd be much better off with the DDS ENG 1-90, which should go just a little bit lower. It should do well crossed 4th order at 1.6, or preferably 1.8 KHz. Could go a bit lower with 48dB/oct. So, with that said.. it'd actually work best if crossed to an 8" midrange in a 3-way. Thing is though, I have to go active, and a 3-way is just too much cash for me right now. So, it's either the little 10" DDS waveguide, or wait to see what happens with AE's new contraption. Anyway, if you're in the US, get it from here: http://www.assistanceaudio.com/10_DDS.html
http://www.ddshorns.com/catalog.php?page=ENG190Pro
I visit that prodance.cz site every day, but I hadn't looked up that waveguide.
On the other hand, it doesn't go anywhere near low enough for anything except maybe a 6" midrange. You'd be much better off with the DDS ENG 1-90, which should go just a little bit lower. It should do well crossed 4th order at 1.6, or preferably 1.8 KHz. Could go a bit lower with 48dB/oct. So, with that said.. it'd actually work best if crossed to an 8" midrange in a 3-way. Thing is though, I have to go active, and a 3-way is just too much cash for me right now. So, it's either the little 10" DDS waveguide, or wait to see what happens with AE's new contraption. Anyway, if you're in the US, get it from here: http://www.assistanceaudio.com/10_DDS.html
http://www.ddshorns.com/catalog.php?page=ENG190Pro
CLS said:
I'm very interested in DDS WG, but I'm not in the US.
I've emailed them several times and got zero response
I experienced the same problem, I got around by having someone in the States to purchase on my behalf and send them via the International post, much cheaper this way on the postal charges.
Ang said:
I'm really not sure how a driver with 2.1 or 2.3mH inductance could be considered for use above about 250Hz anyway.
BHTX said:
We had 2 come from US Speaker that were horrible. The ones coming direct from DDS are not any better though. I had a reliable customer who is using them inform me that 7 out of 7 in one shipment were unuseable. The next shipment he had 3 out of 10 that were bad. Every one of the "good" ones still requires that you grind the throat opening, grind the back so you can get bolts in, etc.
tinitus said:
The 400-800hz rise you see is simply because these are close mic measurements with the driver not on any baffle. Simulate a round 15.5" diameter baffle with the same mic distance and you will see similar results. If measured on an infinitely large baffle this area is nearly flat. It will vary though depending on what baffle size you use.
BHTX said:
See above. Any resonance issues you can clearly see in an impedance curve. Smooth rounded humps are damped quite well and will be shown to disappear quickly in a CSD plot. Measured on an appropriately large baffle, the TD15M is +/- 3dB all the way up to 4KHz.
John
tinitus said:
You can see info on the new 6.5" midrange here:
https://www.aespeakers.com/phpbb2/viewtopic.php?f=1&t=1705
We're at right around 94dB 1W on the 6.5".
John
Ang said:
Take a look at the new Scanspeak Illuminator dome tweeter...looks like it may be crossed very low, maybe with help from a waveguide
A ToneTubby Alnico may work as woofer/mid
despite the enthusiasmen when it was first introduced I have not seen a single report from a user in here, other than I have read that NelsonPass have tried it with a fullrange(?)
Last time I looked at TT site, all driver specs were gone, but I remember at least they have high Qts, and seems logical since they are designed fore open back box(guitar)
Passive crossing at around 1khz, with BSC in mind, should work as charm with the Illuminator dometweeter in waveguide...but compared to a CD it may be a bit restricted in terms of high SPL
If you use a CD/waveguide I think double woofers are needed...in paralel with BSC or as 2.5way
I'm still trying to understand why people would want to use guitar speakers in any kind of a home/hifi type system. The purpose of a guitar speaker is to have crazy breakup to give it's own unique sound.
An example of an eminence alnico guitar speaker would be their Red Fang. take a look at the response.
http://www.eminence.com/pdf/redfang.pdf
There are resonances at 250hz, a bad one at 900hz, then the crazy cone breakup from 1600hz up to 4KHz. The magnitude and frequencies that these breakups occur at determines their "sound" or "coloration". The Red fang has "Vintage British sound with warm undertones and high-end sparkle." The Tone Tubby Alnico drivers are going to have some kind of unique characteristics to their response as well. This is great for guitar, but not at all for an open baffle speaker. The reason for doing a dipole is to get rid of the coloration coming from the enclosure. Why then would you use a driver that has these issues on it's own? These kind of resonances and breakups are what we work so hard to eliminate so our drivers can reproduce exactly what is put into them, not create their own sound.
Alnico alone does help somewhat as it is more resistant to flux field modulation than ceramic magnets. This is why people often regard Alnico drivers to sound so good. A motor with ceramic magnets and a full copper sleeve on the pole though is even more resistive to flux modulation than an alnico motor alone. We're working on getting some properly sized alnico to match the BL of our ceramic motors. Then we'll have both Alnico and the full copper sleeve.
John
An example of an eminence alnico guitar speaker would be their Red Fang. take a look at the response.
http://www.eminence.com/pdf/redfang.pdf
There are resonances at 250hz, a bad one at 900hz, then the crazy cone breakup from 1600hz up to 4KHz. The magnitude and frequencies that these breakups occur at determines their "sound" or "coloration". The Red fang has "Vintage British sound with warm undertones and high-end sparkle." The Tone Tubby Alnico drivers are going to have some kind of unique characteristics to their response as well. This is great for guitar, but not at all for an open baffle speaker. The reason for doing a dipole is to get rid of the coloration coming from the enclosure. Why then would you use a driver that has these issues on it's own? These kind of resonances and breakups are what we work so hard to eliminate so our drivers can reproduce exactly what is put into them, not create their own sound.
Alnico alone does help somewhat as it is more resistant to flux field modulation than ceramic magnets. This is why people often regard Alnico drivers to sound so good. A motor with ceramic magnets and a full copper sleeve on the pole though is even more resistive to flux modulation than an alnico motor alone. We're working on getting some properly sized alnico to match the BL of our ceramic motors. Then we'll have both Alnico and the full copper sleeve.
John
Ribbons/OB mids/sealed Altec 416 midbass + subs
http://www.diyaudio.com/forums/multi-way/100392-beyond-ariel-781.html and http://www.enjoythemusic.com/magazine/equipment/1009/lowther_high_efficiency.htm
Gary uses AE 15” subs with passive radiators.
Thus, because I want to use OBs in a small room-where the left OB would produce little, if any, LF response being too close to the sidewalls and only 3 ft of open space behind it-I thought of setting a midrange OB (and maybe a ribbon tweeter to the side or above it) atop each Altec box. Sealed speakers are more forgiving of less than ideal room placement and the Altecs, handling 700Hz to 70Hz, would thus take boundary problems away from the OBs above it.
I would be using one of my Rythmik 12" sealed servo subs between the Altec 416s.
What midrange driver would you most recommend for this app?
The Altec 414 http://www.greatplainsaudio.com/downloads/414-8B%20Spec%20Sheet.pdf that someone tested here in an OB? http://www.audiocircle.com/index.php?topic=60454.0 However, its 96db to the Altec 416’s 98db.
Maybe one of the Alnico or other drivers from Supravox? http://www.supravox.fr/anglais/les_hp.htm
The Eminence Definimax 12", which had strongly recommended for a midrange
http://www.eminence.com/pdf/Definimax_4012HO.pdf
Or the Beta 12 LTA? http://www.eminence.com/pdf/Beta_12LTA.pdf
They are 96.2 and 97.7db, respectively. The latter seems especially popular among OB builders, plus being a perfect sensitivity match for the Altec 416.
Which might be the ideal midrange for my situation?
Tweeter selection obviously will be the tough choice, given the sensitivities of the drivers to be used below it. Though $$$$, it looks like the only game in town is the RAAL Lazy ribbon.
https://www.madisoundspeakerstore.com/ribbon-tweeters/raal-lazy-ribbon-9-ribbon-tweeter/ Excellent dispersion and > 100db.
Do you think this hybrid OB idea will sound good?
Will it do so without active crossovers?
Please advise on drivers.
Thank you.
I’m a newbie to DIY speaker design. However, I do have a pair of GPA Altec 416 midwoofers in low diffraction sealed boxes. http://www.greatplainsaudio.com/downloads/414-8B%20Spec%20Sheet.pdf The 3 cu ft boxes cut their low end off below 70Hz. The boxes (with rounded prefab corners from http://www.tapeease.com/ ) were designed by fellow diyaudio.com member Gary Dahl, who uses them below his Azurahorn/Radian combo. Gary uses the Altecs from 70Hz up to 700Hz. Indeed, he chose the 416s for his midbass drivers because of their frequently acclaimed tonality-almost certainly due to its Alnico magnet and the low distortion from its underhung voice coil.
http://www.diyaudio.com/forums/multi-way/100392-beyond-ariel-781.html and http://www.enjoythemusic.com/magazine/equipment/1009/lowther_high_efficiency.htm
Gary uses AE 15” subs with passive radiators.
Thus, because I want to use OBs in a small room-where the left OB would produce little, if any, LF response being too close to the sidewalls and only 3 ft of open space behind it-I thought of setting a midrange OB (and maybe a ribbon tweeter to the side or above it) atop each Altec box. Sealed speakers are more forgiving of less than ideal room placement and the Altecs, handling 700Hz to 70Hz, would thus take boundary problems away from the OBs above it.
I would be using one of my Rythmik 12" sealed servo subs between the Altec 416s.
What midrange driver would you most recommend for this app?
The Altec 414 http://www.greatplainsaudio.com/downloads/414-8B%20Spec%20Sheet.pdf that someone tested here in an OB? http://www.audiocircle.com/index.php?topic=60454.0 However, its 96db to the Altec 416’s 98db.
Maybe one of the Alnico or other drivers from Supravox? http://www.supravox.fr/anglais/les_hp.htm
The Eminence Definimax 12", which had strongly recommended for a midrange
http://www.eminence.com/pdf/Definimax_4012HO.pdf
Or the Beta 12 LTA? http://www.eminence.com/pdf/Beta_12LTA.pdf
They are 96.2 and 97.7db, respectively. The latter seems especially popular among OB builders, plus being a perfect sensitivity match for the Altec 416.
Which might be the ideal midrange for my situation?
Tweeter selection obviously will be the tough choice, given the sensitivities of the drivers to be used below it. Though $$$$, it looks like the only game in town is the RAAL Lazy ribbon.
https://www.madisoundspeakerstore.com/ribbon-tweeters/raal-lazy-ribbon-9-ribbon-tweeter/ Excellent dispersion and > 100db.
Do you think this hybrid OB idea will sound good?
Will it do so without active crossovers?
Please advise on drivers.
Thank you.
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