Variac:
I am not necessarily endorsing Eminences, it is just that they are easily available. I wouldn't hold the fact that they have a large selection against them, though.
As far as redoing the frequency response curves-well, I guess if the new models have symmetrical magnetic fields for clarity, I would not find it unreasonable that they did some work with the cone. Most pro speakers would willingly sacrifice smoothness for a little more sensitivity. But as new materials come on the market-who knows?
Yes, I would think the Deltalite would be symmetrical given that passage, especially since every other Pro Series woofer is symmetrical as well.
Anyhow, if you simply don't feel good about Eminence, by all means avoid them.
Don't forget the Fane.
Actually, I have not used either of these, so I cannot really vouch for them that far.
The major purpose of my post was to emphasize the importance of a symmetrical magnetic field, especially if building a ported box.
Just a thought. Without a symmetrical magnetic field, most woofers will travel to the end of their excursions near resonance in a ported box-where the impedance is low at resonance.
Also without a symmetrical magnetic field, some woofers will do the same thing when in free air or in a closed box, where impedance is high at resonance.
I wonder what happens in an aperiodic box, where the impedance is in the middle at resonance-if indeed an aperiodic box can be said to have a resonance at all.
I am not necessarily endorsing Eminences, it is just that they are easily available. I wouldn't hold the fact that they have a large selection against them, though.
As far as redoing the frequency response curves-well, I guess if the new models have symmetrical magnetic fields for clarity, I would not find it unreasonable that they did some work with the cone. Most pro speakers would willingly sacrifice smoothness for a little more sensitivity. But as new materials come on the market-who knows?
Yes, I would think the Deltalite would be symmetrical given that passage, especially since every other Pro Series woofer is symmetrical as well.
Anyhow, if you simply don't feel good about Eminence, by all means avoid them.
Don't forget the Fane.
Actually, I have not used either of these, so I cannot really vouch for them that far.
The major purpose of my post was to emphasize the importance of a symmetrical magnetic field, especially if building a ported box.
Just a thought. Without a symmetrical magnetic field, most woofers will travel to the end of their excursions near resonance in a ported box-where the impedance is low at resonance.
Also without a symmetrical magnetic field, some woofers will do the same thing when in free air or in a closed box, where impedance is high at resonance.
I wonder what happens in an aperiodic box, where the impedance is in the middle at resonance-if indeed an aperiodic box can be said to have a resonance at all.
Hi Mark,
Jammin' Jersey's has the JBL 2226's that Charles (Phase_Accurate) suggested on page one for $200ea. They will give you the 97dbWm with a 40Hz f3 in a 200l box.
Find them here:
http://www.jamminjersey.com/speakers.htm#Speakers
They even have the new "Vent Gap" version capable for 600W.
Jammin' Jersey's has the JBL 2226's that Charles (Phase_Accurate) suggested on page one for $200ea. They will give you the 97dbWm with a 40Hz f3 in a 200l box.
Find them here:
http://www.jamminjersey.com/speakers.htm#Speakers
They even have the new "Vent Gap" version capable for 600W.
OK, First, How can you not be intrigued by Eminence.
I really want to like them because there is no doubt that they can offer the most for the money. They are also open minded about any project it seems. I think that they could make a very high quality audiophile 15" driver if they wanted to or if we ordered 100 of them!! or maybe one of their line sounds great already!
They are also right in the US, so I can easily work with them.
I already have a pair of woofers that are OK. (the JBL's would be better, the TAD even better!!) BUT what I am looking for is a reasonably priced audiophile woofer built along the lines of a pro woofer, that anyone can order and be assured that it's going to sound great. Exactly like Bert Doppenberg, the Oris Horn guy is selling, only 8 ohm, maybe cheaper.
It looks like all we have to do is get 50 people to order a pair each without ever hearing them, and we're in business with Eminence since their minimunm is 100 units. Talk about a group buy.
I'll bet the cost would be about $300 a PAIR!
I really want to like them because there is no doubt that they can offer the most for the money. They are also open minded about any project it seems. I think that they could make a very high quality audiophile 15" driver if they wanted to or if we ordered 100 of them!! or maybe one of their line sounds great already!
They are also right in the US, so I can easily work with them.
I already have a pair of woofers that are OK. (the JBL's would be better, the TAD even better!!) BUT what I am looking for is a reasonably priced audiophile woofer built along the lines of a pro woofer, that anyone can order and be assured that it's going to sound great. Exactly like Bert Doppenberg, the Oris Horn guy is selling, only 8 ohm, maybe cheaper.
It looks like all we have to do is get 50 people to order a pair each without ever hearing them, and we're in business with Eminence since their minimunm is 100 units. Talk about a group buy.
I'll bet the cost would be about $300 a PAIR!
Variac:
I didn't realize you were serious. I thought you were just speculating on something that might have been because you were not interested in Eminence's other offerings.
Intriguing. Getting diyAudio to essentially make their own brand.
Somebody would have to be willing to put them into his garage or basement and be willing to send them to the various members.
I didn't realize you were serious. I thought you were just speculating on something that might have been because you were not interested in Eminence's other offerings.
Intriguing. Getting diyAudio to essentially make their own brand.
Somebody would have to be willing to put them into his garage or basement and be willing to send them to the various members.
>I'm pretty ignorant, but I'm thinking a cast alu frame from the conventional Delta, so that they can stack 2 neo magnets on it to compensate for a heavier cone that will have an Fs around 38 Hz and sooooth response. Waddayou think?
====
I think you need to educate yourself on wide BW HE driver design. If you're going to start with an Eminence design, then the DeltaLite series would be my choice.
====
>I wonder what happens in an aperiodic box, where the impedance is in the middle at resonance-if indeed an aperiodic box can be said to have a resonance at all.
====
Depends on the tuning in relation to Fs, but performance wise, there's no strong audible resonant box output and Fs can be damped to Re, but only a stuffed pipe or compression horn can make a truly flat impedance response.
GM
====
I think you need to educate yourself on wide BW HE driver design.
If you're going to start with an Eminence design, then the DeltaLite series would be my choice.====
>I wonder what happens in an aperiodic box, where the impedance is in the middle at resonance-if indeed an aperiodic box can be said to have a resonance at all.
====
Depends on the tuning in relation to Fs, but performance wise, there's no strong audible resonant box output and Fs can be damped to Re, but only a stuffed pipe or compression horn can make a truly flat impedance response.
GM
Well, clearly I'm not the guy to spec 'em, but those Eminance guys are dying to help and you guys are speaking right up!
I doubt that we would get 50 people to order the drivers without hearing them. BUT things might change if some audio authority would attest that they sound good. That's why that Bert guy is selling piles of them.
At the moment this is just a mental exercise- I wouldn't presume
to really do this on my own!!
So, I tried adding weight to the cone in Win Isd and the response output mainly gets higher at Fs, but doesn't go lower. Now a 300 liter cabinet goes down plenty low, but that's one big cabinet.
What parameters need to be changed to lower the response in a reasonable sized box of say... 120 liters?
My need isn't really very wide bandwith for home stereo. I guess maybe it is for HE. The actual usable flat range would only be from 40hz to 300 or 400 Hz
I agree the the Deltalite is the most appealing on most factors. I just want it to go down to 40hz!!!
I doubt that we would get 50 people to order the drivers without hearing them. BUT things might change if some audio authority would attest that they sound good. That's why that Bert guy is selling piles of them.
At the moment this is just a mental exercise- I wouldn't presume
to really do this on my own!!
So, I tried adding weight to the cone in Win Isd and the response output mainly gets higher at Fs, but doesn't go lower. Now a 300 liter cabinet goes down plenty low, but that's one big cabinet.
What parameters need to be changed to lower the response in a reasonable sized box of say... 120 liters?
My need isn't really very wide bandwith for home stereo. I guess maybe it is for HE. The actual usable flat range would only be from 40hz to 300 or 400 Hz
I agree the the Deltalite is the most appealing on most factors. I just want it to go down to 40hz!!!
As I mentioned before, here they give the ground rules-
Looks like 100 is the minimum
http://editweb.iglou.com/eminence/eminence/pages/products02/oem/welcome.htm
The other option is to convince them that there is a market for the product. After all, they made the Labhorn driver
Good to have your experience on hand
Looks like 100 is the minimum
http://editweb.iglou.com/eminence/eminence/pages/products02/oem/welcome.htm
The other option is to convince them that there is a market for the product. After all, they made the Labhorn driver
Good to have your experience on hand
I have no interest in a 25 hz product. Too many compromises.
However I meant flat in room to 40hz, which would mean there is some bass below that. I agree that people latch onto specs that they don't understand-including myself.
Still, I think a great sounding product that goes down to 40 would appeal to a good sized group of knowledgable DIYers (at least 50? hmmmmm)but maybe you are right in that Eminence wouldn't see a big enough market to produce it on their own.
However I meant flat in room to 40hz, which would mean there is some bass below that. I agree that people latch onto specs that they don't understand-including myself.
Still, I think a great sounding product that goes down to 40 would appeal to a good sized group of knowledgable DIYers (at least 50?
hmmmmm)but maybe you are right in that Eminence wouldn't see a big enough market to produce it on their own.A) If all you want to do is to get down to 40 Hz in a 4 Ft³ box, wouldn't a 10 inch do? Remember that at resonance, a woofer in a ported box only has to travel ¼ the distance to produce the same bass output that the same woofer would in a sealed box. At resonance, a 10" woofer in a ported box is the equivalent of a 20 inch woofer in a sealed box.
B) For a while now, I have been thinking of taking a typical non-symmetrical magnetic field woofer, removing the dust cap, and gluing iron slugs or washers on the end of the pole piece to see if I can prevent the "suck-out" phenomenon. Just remove the dust cap, run the speaker, and keep adding slugs until it doesn't move to the end of it's travel at resonance. Of couse, the slugs would be just a little less than the diameter of pole piece. Very thin "shim stock" is easily available at hardware stores for really thin washers . Of course, I would not run the speaker while I was gluing, LOL. If such an experiment works, then you can vastly increase your selection of drivers by this method.
I would probably have to fabricate a larger dust cap to allow for the extra room, but that does not apear to be a huge problem.
B) For a while now, I have been thinking of taking a typical non-symmetrical magnetic field woofer, removing the dust cap, and gluing iron slugs or washers on the end of the pole piece to see if I can prevent the "suck-out" phenomenon. Just remove the dust cap, run the speaker, and keep adding slugs until it doesn't move to the end of it's travel at resonance. Of couse, the slugs would be just a little less than the diameter of pole piece. Very thin "shim stock" is easily available at hardware stores for really thin washers . Of course, I would not run the speaker while I was gluing, LOL.
If such an experiment works, then you can vastly increase your selection of drivers by this method.I would probably have to fabricate a larger dust cap to allow for the extra room, but that does not apear to be a huge problem.
GM said:
I meant in reference to the "suck out" peneomenon. With no pronounced impedance changes at resonance in an aperiodic box, I wonder if the woofer will exhibit the 'suck out" phenomenon. After all, it mostly seems to happen as resonance is approached in the ported and even "free air" situations.
reply
How about the Eminence Magnum pro series then?
the 15 pro ho and 15 pro lf have copper shorting rings and aluminium phase plug with a cloth dust cap over that.
www.eminence-speaker.com
How about the Eminence Magnum pro series then?
the 15 pro ho and 15 pro lf have copper shorting rings and aluminium phase plug with a cloth dust cap over that.
www.eminence-speaker.com
>That's why that Bert guy is selling piles of them.
====
Don't know that he is, but he appears to have done his level best to ~replicate the Altec 515-G series, which is considered by many of the cognoscenti as the best sounding 15" LF/midbass driver ever made, which would go a long ways toward sonic credibility.
====
>So, I tried adding weight to the cone in Win Isd and the response output mainly gets higher at Fs, but doesn't go lower.
====
Then there's something wrong with either how you inputted it or the program (I know WINISD has some 'bugs' and don't trust it one whit) since adding mass lowers Fs/eff, raises Qts, increasing Vb/lowering Fb for a max flat alignment.
mass(m) = (22.428*dia^4(cm))/(Fs^2*Vas(liters))
m' = m + mass added
mass ratio(mr) = m'/m
Fs' = Fs/mr^0.5
Qes' = Qes*mr^0.5
Qms' = Qms*mr^0.5
then: Qts' = (Qes'*Qms')/(Qes'+Qms')
Vas is unchanged
n0' = 9.614*10^-10*Fs'^3*Vas(liters)/Qes'
SPLeff' = 112.02+10*Log(n0)
====
>Now a 300 liter cabinet goes down plenty low, but that's one big cabinet.
====
It's the price you pay for efficiency.
====
>What parameters need to be changed to lower the response in a reasonable sized box of say... 120 liters?
====
You can juggle numbers to get the desired Vb/response, but the easiest is to spec (in this case) Vas = Vb = 120L, Fs = Fb = 0.707*40Hz = 28.28Hz, Qts = 0.403.
The greater Vas is and/or the lower Qes is, the higher efficiency is.
====
>My need isn't really very wide bandwith for home stereo. I guess maybe it is for HE. The actual usable flat range would only be from 40hz to 300 or 400 Hz
====
Then the driver ideally needs a smooth BW from 28.28-1600Hz. You can narrow it up to 28.28-800Hz if 4th order/adj. TD is used, but most DIYers don't like to go this route.
====
>I agree the the Deltalite is the most appealing on most factors. I just want it to go down to 40hz!!!
====
I didn't suggest using it as is, but using it as a base design to mod to suit.
====
>I wonder if the woofer will exhibit the 'suck out" phenomenon.
====
With highly damped box and driver resonances, I don't see how it can. I certainly don't recall seeing it happen in all the aperiodic designs I've built. The driver just rolls off at ~6dB/octave, like when mounted on an open baffle.
GM
====
Don't know that he is, but he appears to have done his level best to ~replicate the Altec 515-G series, which is considered by many of the cognoscenti as the best sounding 15" LF/midbass driver ever made, which would go a long ways toward sonic credibility.
====
>So, I tried adding weight to the cone in Win Isd and the response output mainly gets higher at Fs, but doesn't go lower.
====
Then there's something wrong with either how you inputted it or the program (I know WINISD has some 'bugs' and don't trust it one whit) since adding mass lowers Fs/eff, raises Qts, increasing Vb/lowering Fb for a max flat alignment.
mass(m) = (22.428*dia^4(cm))/(Fs^2*Vas(liters))
m' = m + mass added
mass ratio(mr) = m'/m
Fs' = Fs/mr^0.5
Qes' = Qes*mr^0.5
Qms' = Qms*mr^0.5
then: Qts' = (Qes'*Qms')/(Qes'+Qms')
Vas is unchanged
n0' = 9.614*10^-10*Fs'^3*Vas(liters)/Qes'
SPLeff' = 112.02+10*Log(n0)
====
>Now a 300 liter cabinet goes down plenty low, but that's one big cabinet.
====
It's the price you pay for efficiency.
====
>What parameters need to be changed to lower the response in a reasonable sized box of say... 120 liters?
====
You can juggle numbers to get the desired Vb/response, but the easiest is to spec (in this case) Vas = Vb = 120L, Fs = Fb = 0.707*40Hz = 28.28Hz, Qts = 0.403.
The greater Vas is and/or the lower Qes is, the higher efficiency is.
====
>My need isn't really very wide bandwith for home stereo. I guess maybe it is for HE. The actual usable flat range would only be from 40hz to 300 or 400 Hz
====
Then the driver ideally needs a smooth BW from 28.28-1600Hz. You can narrow it up to 28.28-800Hz if 4th order/adj. TD is used, but most DIYers don't like to go this route.
====
>I agree the the Deltalite is the most appealing on most factors. I just want it to go down to 40hz!!!
====
I didn't suggest using it as is, but using it as a base design to mod to suit.
====
>I wonder if the woofer will exhibit the 'suck out" phenomenon.
====
With highly damped box and driver resonances, I don't see how it can. I certainly don't recall seeing it happen in all the aperiodic designs I've built. The driver just rolls off at ~6dB/octave, like when mounted on an open baffle.
GM
Bull: I've stumbled on the Magnum pro HO before and you are right: It fits all my requirements on paper. The efficiency is down to about 95.5 dB but that is the price you pay for the lower response and that's enough dB for me. The area that I wantedto be flat is flat according to the graph. My biggest concern is that there is some negative effect due to it's emphasis on handling huge amounts of power-maybe we lose some subtlety?
GM: what do you think?
I don't know how many Bert is selling, but got the idea that he has moved the crucial minimum first order!
That Altec seems to be revered as the best - I guess based on that model? What were the years it was made? (just curious) In what ways does Bert's seem to match the Altec?
here are his specs:
Fs - 38.9 Hz, Re - 13.6 ohm, Mms - 66 gr., BL - 28.5, Qts - 0.25, Qes - 0.26, Qms - 5.12, Vas - 258.2 liter, Vd - 513 dm3, Rms - 3.16, Sd - 855 cm2, Coil height - 7mm, Air Gap height - 14mm, Sensitivity - 99.6dB, Power - 150Watt, Overal diameter - 388 mm
Maybe you are on to how to make the great driver- copy the Altec! I would imagine that this has ben tried before? It must not be easy to get right. Maybe it's just that the pro market has gone chasing power handlig rather than quality sound
I 'm pretty sure the Altec uses an Alnico magnet, so if you believe that this is important, Eminence might still be able to come through since they still make guitar speakers with alnico. I'm kinda hoping that the Neo magnets exibit the positive characteristics of alnico- based on no evidence except that they are different than ferrite. Well also I have discovered that some TAD speakers use Neo mag drivers now so thats a recomentdation...
I know a 10" would make the cabinet smaller, in fact the 12"
Deltalite seems fine for about a 150 liter cab. . It's just that I have a 15" now and it seems to work almost like a flat panel! the movement is so small that I can't help thaink that that is why the sound is so un distorted. Besides, 15" are the big fad these days.....
GM: what do you think?
I don't know how many Bert is selling, but got the idea that he has moved the crucial minimum first order!
That Altec seems to be revered as the best - I guess based on that model? What were the years it was made? (just curious) In what ways does Bert's seem to match the Altec?
here are his specs:
Fs - 38.9 Hz, Re - 13.6 ohm, Mms - 66 gr., BL - 28.5, Qts - 0.25, Qes - 0.26, Qms - 5.12, Vas - 258.2 liter, Vd - 513 dm3, Rms - 3.16, Sd - 855 cm2, Coil height - 7mm, Air Gap height - 14mm, Sensitivity - 99.6dB, Power - 150Watt, Overal diameter - 388 mm
Maybe you are on to how to make the great driver- copy the Altec! I would imagine that this has ben tried before? It must not be easy to get right. Maybe it's just that the pro market has gone chasing power handlig rather than quality sound
I 'm pretty sure the Altec uses an Alnico magnet, so if you believe that this is important, Eminence might still be able to come through since they still make guitar speakers with alnico. I'm kinda hoping that the Neo magnets exibit the positive characteristics of alnico- based on no evidence except that they are different than ferrite. Well also I have discovered that some TAD speakers use Neo mag drivers now so thats a recomentdation...
I know a 10" would make the cabinet smaller, in fact the 12"
Deltalite seems fine for about a 150 liter cab. . It's just that I have a 15" now and it seems to work almost like a flat panel! the movement is so small that I can't help thaink that that is why the sound is so un distorted. Besides, 15" are the big fad these days.....
Here's the specs on the Magnum 15 HO:
http://www.partsexpress.com/pdf/290-580.pdf
Bull wins, this was exactly what I was asking for- except, I wonder how it sounds?
Sells for about $245 ea at Parts Express
http://www.partsexpress.com/pdf/290-580.pdf
Bull wins, this was exactly what I was asking for- except, I wonder how it sounds?
Sells for about $245 ea at Parts Express
And the difference between Kappa Pro LF and Magnum Pro LF Is??
Below is a WinISD simulation for both the eminence Kappa Pro 15LF and the Magnum Pro 15 HO. Each are in a 4 Ft³ box tuned to 40 Hz.
Differences?
Less than 1 dB difference at 50 Hz. And the difference goes down from there.
Kappa achieves symmetrical magnetic field with an extended pole piece. Magnum uses Faraday ring.
Kappa lists for $189. Parts Express should sell cheaper. Magnum more expensive.
Kappa Pro 15 LF in red.
Magnum Pro 15 HO in blue.
Below is a WinISD simulation for both the eminence Kappa Pro 15LF and the Magnum Pro 15 HO. Each are in a 4 Ft³ box tuned to 40 Hz.
Differences?
Less than 1 dB difference at 50 Hz. And the difference goes down from there.
Kappa achieves symmetrical magnetic field with an extended pole piece. Magnum uses Faraday ring.
Kappa lists for $189. Parts Express should sell cheaper. Magnum more expensive.
Kappa Pro 15 LF in red.
Magnum Pro 15 HO in blue.
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