Jim; I finished the thread on the big box last night and at one point on page 7 you said it was bigger (wider) than it needs to be. How much narrower can it be without adversely affecting the output? I am thinking somthing between your big box and your SS15 would be good for me?
Thanks Andy
Why is the big box limited to 50 volts?
Thanks Andy
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Andy: I have modeled Jim's big TH with internal width of 20 inches with less than 1 dB loss. Jim red-lines his box to prevent the speaker from exceeding its
safe travel. His limit of 50 volts is only necessary around 41 Hz, and equates to 312 Watts. Crank it up to 60 volts (450 Watts) and you'll get a little distortion
only if you have a loud note close to 41 Hz. Crank it up to 600 Watts, and the driver might hit its limit and blow!
When you control your media, it's possible to edit the sound, reducing the sound level in selected sections, while boosting the AVERAGE power.
GoldWave and Audacity are two programs that allow you to limit or compress the signal which selectively limits the drivers excursion.
safe travel. His limit of 50 volts is only necessary around 41 Hz, and equates to 312 Watts. Crank it up to 60 volts (450 Watts) and you'll get a little distortion
only if you have a loud note close to 41 Hz. Crank it up to 600 Watts, and the driver might hit its limit and blow!
When you control your media, it's possible to edit the sound, reducing the sound level in selected sections, while boosting the AVERAGE power.
GoldWave and Audacity are two programs that allow you to limit or compress the signal which selectively limits the drivers excursion.
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I don't think I can correctly answer your question, but I'll give it a shot.
Tapped horns have 2 excursion minimums, not a single minimum like a ported cabinet. (In pa style tapped horn cabinets, they are usually close to 40 and 100hz) Between those minimums is where the driver actually hits xmax first, and ultimately is the limiting factor on how much power you can safely apply. The big box has the lower minimum below 40hz, the ss15 above 40hz. The lower in freq the excursion maximum is, it seems the less power it takes to get to xmax at that freq. Probably more important however, the big box has a larger cross section, with a lower compression ratio and therefore has less 'resistance' to driver excursion. This is probably the biggest factor on why it reaches xmax at lower power levels.
Regardless -- Personally, I would want a pair of ss15's over a big box any day, for any reason if money, etc. was of no concern.
If you want to only be 50' away from your audience a 60degree wide horn only covers 58' You for SURE want to go with a wider format horn on your PSD driver.
Bi-amp on the tops is the perfect way to address crossover. Forget the apt200, buy the goldwood horn, build the eminence suggested small ported cabinet for the kappa 15a's and be happy.
Build a pair of ss15's for each top, and you'll have the ability to exceed THX levels at 100' spacing, 50 feet from audience at 40-15000, which is your stated goal.
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Typos and Stuff.
Hi 4pyros,
As an aside, as this is my second language, I usually type into another text window just to have an easier time to proofread my entries, then copy and paste over here. Sometimes I'm so punch-drunk that I have to open a second google window, and type the word in question into it to even get close (the google is a great free spell checker
). For what it's worth, I think you started an interesting thread.
I have a LAB15 tapped horn design in the works that may be worth looking at, I'll look it over one more time, and try posting it tomorrow. I would also definitely recommend that you take jbell up on his offer to "mod" the design of the SS15 (would that make that model the SS15M?):
http://www.diyaudio.com/forums/subwoofers/170771-single-sheet-th-challenge-23.html Post #228.
jbell is a master at squeezing "blood" from a piece of plywood. Well, gotta go....
Regards,
Hi 4pyros,
As an aside, as this is my second language, I usually type into another text window just to have an easier time to proofread my entries, then copy and paste over here. Sometimes I'm so punch-drunk that I have to open a second google window, and type the word in question into it to even get close (the google is a great free spell checker
). For what it's worth, I think you started an interesting thread.I have a LAB15 tapped horn design in the works that may be worth looking at, I'll look it over one more time, and try posting it tomorrow. I would also definitely recommend that you take jbell up on his offer to "mod" the design of the SS15 (would that make that model the SS15M?):
http://www.diyaudio.com/forums/subwoofers/170771-single-sheet-th-challenge-23.html Post #228.
jbell is a master at squeezing "blood" from a piece of plywood. Well, gotta go....
Regards,
Hey Pyros - no worries. If I didn't have spell check you wouldn't understand 1/2 of what I type.
The DCX2496 is good because it is soooo flexible. And the price is right. You can set it up exactly how you want, simple or complex. And it does delay on any or all channels. There are other very nice crossovers on the market, too. Have a look at Rane and Ashely. Very good stuff. Less flexible, but more ruggedly built than the DCX.
Whatever you get, someone here can help you with it. Don't know if you need to or want to run your rig in stereo. That's something to think about. Mono sum for your new subs is probably a good idea however you do the rest.
The DCX2496 is good because it is soooo flexible. And the price is right. You can set it up exactly how you want, simple or complex. And it does delay on any or all channels. There are other very nice crossovers on the market, too. Have a look at Rane and Ashely. Very good stuff. Less flexible, but more ruggedly built than the DCX.
Whatever you get, someone here can help you with it. Don't know if you need to or want to run your rig in stereo. That's something to think about. Mono sum for your new subs is probably a good idea however you do the rest.
TB46; I do both of those things, Post one was a word doc and google is always open in another window. I miss spell cheak but will get it back some day. Just trying to get along for now. I would like to see your design for the LAB15. But I will probly go with the SS15. I believe Jims offer to "MOD" a design was for a top or mid range using the KAPPA PRO-15 speakers I have. Andy
Jim; I know you are right but I have to ask. It seems funny to have 15" subs and 15" mids. Can I do with 12" mids or do I need the 15" to pick up whare the SS15s leave off?
Trying to work out of the Eminence catalog. Thay have some 2" horn flares with 90 degree dispersion, can you recommend any fo them?
One big question I have now is the spacing of the sets at 50' feet from the audience using two SS15s on there sides? and 90 degree horns on the HF drivers is 100 foot spacing going to be the best or should I go with something closer, 75' 50'? Andy
Trying to work out of the Eminence catalog. Thay have some 2" horn flares with 90 degree dispersion, can you recommend any fo them?
One big question I have now is the spacing of the sets at 50' feet from the audience using two SS15s on there sides? and 90 degree horns on the HF drivers is 100 foot spacing going to be the best or should I go with something closer, 75' 50'? Andy
AFAIK, the QSC stuff is 2 output only. So you'd need more than one for 3-way. Something like a Rane AC 22S or Ashly XR-1001 would be a good and simple start for you. What is Jim using?
I do like to have my subs on a separate send so that I can keep things like vocals out of them. No boom-thump on the announcements. Also easier to dial the low freqs. in or out that way. Every sound guy has his own tastes.
To tell the truth, I've been using Meyer Sound active speakers for so long, I've almost forgotten what a crossover or amplifier are.
I do like to have my subs on a separate send so that I can keep things like vocals out of them. No boom-thump on the announcements. Also easier to dial the low freqs. in or out that way. Every sound guy has his own tastes.
To tell the truth, I've been using Meyer Sound active speakers for so long, I've almost forgotten what a crossover or amplifier are.
Comparison between 3015LF and LAB15
Hi again,
Here is a comparison between the jbell Stadium Horn and a model of a LAB15 tapped horn. I used the Par flare for both models, as it supposedly more closely reflects what we build. Both models end up with about 607-608 Liter internal volume. I used Ang=2.0 x Pi and Eg=2.83. As modern high powered amplifiers are generally pretty stiff in their voltage output, I think the small difference in Re between the drivers doesn't matter.
From the Eminence data sheets:
Kappalite 3015LF:
- Xmax=9.6mm
- Xlim=17mm
- Power Ratings=450/900W
LAB15:
- Xmax=11.8mm
- Xlim=22mm
- Power Ratings=600/1200W
From Hornresp:
jbell's Stadium horn w/ 3015LF reaches:
- Xmax w/ 180W/8Ohm @ 41Hz Eg=37.95V
- Xlim w/ 560W/8Ohm @ 41Hz Eg=66.93V
tb46 model horn w/ LAB15 reaches:
- Xmax w/ 450W/8Ohm @ 38Hz Eg=60.00V
- Xlim w/ 1570W/8Ohm @ 38Hz Eg=112.07V
In other words the 3015LF would struggle @ its rated power limits while the LAB15 still has excursion to spare. Obviously there would be a premium price attached to the LAB15 and amplifier combination, but when you are looking for low frequency extension and high output it looks like a promising driver.
Let me know what I got wrong.
Regards,
P.S.: Had to break the picture up into three parts, just stick 'em on top of each other.
Hi again,
Here is a comparison between the jbell Stadium Horn and a model of a LAB15 tapped horn. I used the Par flare for both models, as it supposedly more closely reflects what we build. Both models end up with about 607-608 Liter internal volume. I used Ang=2.0 x Pi and Eg=2.83. As modern high powered amplifiers are generally pretty stiff in their voltage output, I think the small difference in Re between the drivers doesn't matter.
From the Eminence data sheets:
Kappalite 3015LF:
- Xmax=9.6mm
- Xlim=17mm
- Power Ratings=450/900W
LAB15:
- Xmax=11.8mm
- Xlim=22mm
- Power Ratings=600/1200W
From Hornresp:
jbell's Stadium horn w/ 3015LF reaches:
- Xmax w/ 180W/8Ohm @ 41Hz Eg=37.95V
- Xlim w/ 560W/8Ohm @ 41Hz Eg=66.93V
tb46 model horn w/ LAB15 reaches:
- Xmax w/ 450W/8Ohm @ 38Hz Eg=60.00V
- Xlim w/ 1570W/8Ohm @ 38Hz Eg=112.07V
In other words the 3015LF would struggle @ its rated power limits while the LAB15 still has excursion to spare. Obviously there would be a premium price attached to the LAB15 and amplifier combination, but when you are looking for low frequency extension and high output it looks like a promising driver.
Let me know what I got wrong
.Regards,
P.S.: Had to break the picture up into three parts, just stick 'em on top of each other.
Attachments
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Hi Andy,
The box width has to be wide enough to allow the speaker to fit, 20" external sounds fine (anything above 17"). I just don't have the time right now to work on a folding. I also have not found the time to test the LAB15 drivers I have on hand, and I would be reluctant to spend a great deal of time on a design and build without having actual, measured T/S parameters. Maybe you can get additional information from Eminence. I did want to provide some food for thought for the experts though. Also, there is a lot of room to play once you say "money doesn't matter" as long as it's Eminence, e.g.: in the same size box a parallel dual of LAB15s limited to flat to 40Hz (-10dB @ 30Hz) will get past 105dB @ Eg=2.83V with a relatively nice frequency response for a tapped horn.
Regards,
The box width has to be wide enough to allow the speaker to fit, 20" external sounds fine (anything above 17"). I just don't have the time right now to work on a folding. I also have not found the time to test the LAB15 drivers I have on hand, and I would be reluctant to spend a great deal of time on a design and build without having actual, measured T/S parameters. Maybe you can get additional information from Eminence. I did want to provide some food for thought for the experts though. Also, there is a lot of room to play once you say "money doesn't matter" as long as it's Eminence, e.g.: in the same size box a parallel dual of LAB15s limited to flat to 40Hz (-10dB @ 30Hz) will get past 105dB @ Eg=2.83V with a relatively nice frequency response for a tapped horn.
Regards,
Hi Andy,
Just noticed that in Post #51 your are saying: "...go with the SS15. I believe Jims offer to "MOD" a design was for a top or mid range...". You better refer back to that thread, the offer there was for modifying the SS15. The SS15 seems to be a great sub, great price/performance ratio.
Regards,
Just noticed that in Post #51 your are saying: "...go with the SS15. I believe Jims offer to "MOD" a design was for a top or mid range...". You better refer back to that thread, the offer there was for modifying the SS15. The SS15 seems to be a great sub, great price/performance ratio.
Regards,
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