When can we get a Thomann store here in North America? =P
The 15LB100 is only $20 more than the PA310?!?!?! Then that makes the 15LB100 is an absolutely outstanding value !!!
I wish i could get that driver here in the states for such a low price.
I just did a quick & dirty HR sim of that P-Audio E15-600S and it is alright, it will work but does not have the motor strength of the 15LB100 .... According to our models The P-Audio driver would benefit from some additional internal airspace unless you don't mind the bump at 60hz and a significant rolloff down at 40hz (some people may prefer this old-school punchy PA style bass curve)...
GOOD QUESTION!! I assume Akabak is operating in halfspace (2pi) by default ...... I am sure there must be a way to add a large boundary so you can simulate Quarterspace (1pi) ..
The 15LB100 is only $20 more than the PA310?!?!?! Then that makes the 15LB100 is an absolutely outstanding value !!!
I wish i could get that driver here in the states for such a low price.
I just did a quick & dirty HR sim of that P-Audio E15-600S and it is alright, it will work but does not have the motor strength of the 15LB100 .... According to our models The P-Audio driver would benefit from some additional internal airspace unless you don't mind the bump at 60hz and a significant rolloff down at 40hz (some people may prefer this old-school punchy PA style bass curve)...
GOOD QUESTION!! I assume Akabak is operating in halfspace (2pi) by default ...... I am sure there must be a way to add a large boundary so you can simulate Quarterspace (1pi) ..
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The 15LB100 is only $20 more than the PA310?!?!?! Then that makes the 15LB100 is an absolutely outstanding value !!!
I wish i could get that driver here in the states for such a low price.
Well, before you get too excited, Dayton 310 is still 120$ and The Box is 142$ to the doorstep in Denmark🙄 But yes, The Box is a good value, especially here in Europe.
I found something in Akabak named Def Reflector, that must be it...😉
I tried the Box in a larger cabinet ca. 120l total (90+30). It reaches 35 hz, but lose some sensitivity + can handle less power due to x-max limit, so I think 100 L is optimal, as you suggest. I will try to make the cabinet higher and slimmer (H:75 W:45 D:35) and see what happens 🙂
The 15PZB40 looks like a good one ...... I am also testing out the new "Jag Fix"
Freddi ,
The 15PZB40 looks excellent in a the 100L 40hz tuned Karlflex model
The response shows useful output up to 2khz on-axis ... Do you have any polar pattern measurements for that driver? Could make a great two-way system crossed over at somewhere between 1khz to 2khz (depending on what the off-axis response allows for) 😀 ...
If i choose to use the "Large Voice Coil" option (The Jag Fix) in Loudspeaker Wizard the response goes from looking mildly underdamped to mildly overdamped which is fine (the difference is more drastic than just doubling the Le figure on the HR inputs page) .... I am assuming that a 4" diameter voicecoil must qualify as a "Large Voice Coil"
Freddi ,
The 15PZB40 looks excellent in a the 100L 40hz tuned Karlflex model
The response shows useful output up to 2khz on-axis ... Do you have any polar pattern measurements for that driver? Could make a great two-way system crossed over at somewhere between 1khz to 2khz (depending on what the off-axis response allows for) 😀 ...If i choose to use the "Large Voice Coil" option (The Jag Fix) in Loudspeaker Wizard the response goes from looking mildly underdamped to mildly overdamped which is fine (the difference is more drastic than just doubling the Le figure on the HR inputs page) .... I am assuming that a 4" diameter voicecoil must qualify as a "Large Voice Coil"
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To be clear
Clarification of the above post: Referring to B&C's response chart for an idea of what the upper end response can be (if the front of the cone is not obscured , as in aperture style "D" or "E"), and then the quick & dirty HR sim to get an idea of the bottom end will look like ...
Clarification of the above post: Referring to B&C's response chart for an idea of what the upper end response can be (if the front of the cone is not obscured , as in aperture style "D" or "E"), and then the quick & dirty HR sim to get an idea of the bottom end will look like ...
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wish I taken on and off axis graphs when I had 15pzb40 outdoors some years ago - maybe one of these days I'll get it into something light enough to carry
XLS weirdness using the RCA connections
Freddi ,
Did you say that you are using an Crown XLS series amplifier?
If so have you tried using the RCAs , or just the balanced XLR or 1/4" TRS connections?
I think i just noticed a problem ....
Using the RCA connections along with the amp's front panels set at 50% there is some sort of strange distortion that sounds like a midrange shout or some sort of ugly non-linearity that just comes and goes and only reveals itself sometimes depending on the material i am playing ..... The problem goes away when I turn the gains to 100% and at this setting the midrange sounds smooth and rich with all material, no more weirdness .......... Using HOLMimpulse software the response measurements and phase measurements are all the same regardless of whether the amp's gains are at 50% or 100% but with music there is an audible difference, what do you make of that?
I think it might have to do with this USB sound interface not liking the load it is seeing on it's outputs, or something like that *shrug* ...
I am going to switch to a different sound interface with balanced outputs so i maybe it won't matter anymore, but i just thought i might say a something about this quirk ...
Freddi ,
Did you say that you are using an Crown XLS series amplifier?
If so have you tried using the RCAs , or just the balanced XLR or 1/4" TRS connections?
I think i just noticed a problem ....
Using the RCA connections along with the amp's front panels set at 50% there is some sort of strange distortion that sounds like a midrange shout or some sort of ugly non-linearity that just comes and goes and only reveals itself sometimes depending on the material i am playing ..... The problem goes away when I turn the gains to 100% and at this setting the midrange sounds smooth and rich with all material, no more weirdness .......... Using HOLMimpulse software the response measurements and phase measurements are all the same regardless of whether the amp's gains are at 50% or 100% but with music there is an audible difference, what do you make of that?
I think it might have to do with this USB sound interface not liking the load it is seeing on it's outputs, or something like that *shrug* ...
I am going to switch to a different sound interface with balanced outputs so i maybe it won't matter anymore, but i just thought i might say a something about this quirk ...
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re: XLS - mine is hooked up from an ancient Dell soundcard to a RCA jack - current gain level around 3 o'clockj - probably lower gains at times - like 10 o'clock - its seemed to sound ok with RCA inputs
here's a cheap Selenium driver on an Altec 511B 491Hz sine tone a month ago or so off my Crown - the mic preamp/phantom supply is an M-Audio "Buddy" - not sure of the gain setting
I've added distortion at times with aural "exciters" 😀
here's a cheap Selenium driver on an Altec 511B 491Hz sine tone a month ago or so off my Crown - the mic preamp/phantom supply is an M-Audio "Buddy" - not sure of the gain setting
I've added distortion at times with aural "exciters" 😀
Gear chat
That Selenium graph seems acceptably clean, no gross harmonic distortion problems there, certainly not anything that will be obvious to the listener ....
Nothing looked out of place in my measurements either, even when i used the THD option in HOLMimpulse, it looked fine, but i could hear something that didn't sound right until i turned the gains up higher on the amp then everything straightened out, weird eh? It probably has something to do with this wonky usb sound interface i am using (also contains the balanced mic preamp and phantom power supply) , this interface might also have something to do with with the Dayton mic's flaky behavior .... Time for it to go i think
Do you like your M-audio pre? I am replacing this interface with one from M-audio, just waiting for it to be delivered 🙂 I also have a few cheap Lexicon brand usb sound cards/recording interfaces , i use one for playback (from a PC) connected to the system in the living room and one in the bedroom for playback and they work incredibly well for that, they sound better than any typical PC soundcard and you can find them selling for bargain basement prices on ebay, i also noticed that there are many of these sorts of things selling locally here at pawn shops in the Phoenix area (i would imagine the same could also be the case in some other towns across the country) ...
You are using an Aural Exciter , like the Aphex units?
That Selenium graph seems acceptably clean, no gross harmonic distortion problems there, certainly not anything that will be obvious to the listener ....
Nothing looked out of place in my measurements either, even when i used the THD option in HOLMimpulse, it looked fine, but i could hear something that didn't sound right until i turned the gains up higher on the amp then everything straightened out, weird eh? It probably has something to do with this wonky usb sound interface i am using (also contains the balanced mic preamp and phantom power supply) , this interface might also have something to do with with the Dayton mic's flaky behavior .... Time for it to go i think
Do you like your M-audio pre? I am replacing this interface with one from M-audio, just waiting for it to be delivered 🙂 I also have a few cheap Lexicon brand usb sound cards/recording interfaces , i use one for playback (from a PC) connected to the system in the living room and one in the bedroom for playback and they work incredibly well for that, they sound better than any typical PC soundcard and you can find them selling for bargain basement prices on ebay, i also noticed that there are many of these sorts of things selling locally here at pawn shops in the Phoenix area (i would imagine the same could also be the case in some other towns across the country) ...
You are using an Aural Exciter , like the Aphex units?
Hi Matthew, it seems that a hight of 75 cm is to much, because of too long internal path, function of quarter-wave. The bass reaches to deep (30hz) but falls in amplitude at the same time.
Maybe I could imploy the parasitic chamber in the bottom, as you have done on some models. How would that look node-wise?
Maybe I could imploy the parasitic chamber in the bottom, as you have done on some models. How would that look node-wise?
Ideas for increasing Karlflex height ..
Sebastian,
Yes, using a parasitic chamber at the bottom is one way to get the extra height, but it is a complicated way .....
Another way (without any extra complication) would be to in increase the height of both the main vent and the Freddi-mod absorber cavity (currently both at 2.5" tall or 6.3cm) ... The effect would be a beneficial increase in front chamber volume because the Freddi-mod cavity is part of the front chamber, and the fundamental tuning (FB) would also shift upward since the main vent's cross sectional area has been increased (also requiring that the main vent be made slightly shorter so there is is no excessive CSA pinch at the turn where it connects to the rear chamber) ...............S1 length would also be made shorter by the exact amount taken up by the new taller absorber cavity.............. These changes would take away from the total path length of this taller cabinet, helping to maintain a proper tuning ......... You could also move the baffle back (into the cab) by another 3cm which would further increase the front chamber volume (which is great) while shortening the main vent allowing another small upward shift in tuning .....
If the resulting response looks exceedingly underdamped (saddle shaped) then the cabinet width could be reduced by a couple of inches to reduce internal volume ....
Sebastian , if you prefer i can make the changes in the script and post it, or if you welcome the exercise you can do it .... Let me know 🙂
Sebastian,
Yes, using a parasitic chamber at the bottom is one way to get the extra height, but it is a complicated way .....
Another way (without any extra complication) would be to in increase the height of both the main vent and the Freddi-mod absorber cavity (currently both at 2.5" tall or 6.3cm) ... The effect would be a beneficial increase in front chamber volume because the Freddi-mod cavity is part of the front chamber, and the fundamental tuning (FB) would also shift upward since the main vent's cross sectional area has been increased (also requiring that the main vent be made slightly shorter so there is is no excessive CSA pinch at the turn where it connects to the rear chamber) ...............S1 length would also be made shorter by the exact amount taken up by the new taller absorber cavity.............. These changes would take away from the total path length of this taller cabinet, helping to maintain a proper tuning ......... You could also move the baffle back (into the cab) by another 3cm which would further increase the front chamber volume (which is great) while shortening the main vent allowing another small upward shift in tuning .....
If the resulting response looks exceedingly underdamped (saddle shaped) then the cabinet width could be reduced by a couple of inches to reduce internal volume ....
Sebastian , if you prefer i can make the changes in the script and post it, or if you welcome the exercise you can do it .... Let me know 🙂
Matthew, thank you so much, I will try to armwrestle with Akabak following your tips. If I lose, then I'll cry for help 😀
Alright , and hey check out this driver =)
Ok, sounds good, you know where to find me 😀
In the meantime i have to post about this great deal on an 18" driver! It is from PRV , those Brazilians make some great stuff sometimes!
This driver (link below) would be fantastic in a 24" x 24" x 24" cube shaped Karlflex! I don't want to get ahead of myself though , i still have to finish the Sketches for the basic K-flex box ... . Great deal for $170
PRV Audio 18SW2000 18" High Power Pro Audio Subwoofer 8 Ohm
Ok, sounds good, you know where to find me 😀
In the meantime i have to post about this great deal on an 18" driver! It is from PRV , those Brazilians make some great stuff sometimes!
This driver (link below) would be fantastic in a 24" x 24" x 24" cube shaped Karlflex! I don't want to get ahead of myself though , i still have to finish the Sketches for the basic K-flex box ... . Great deal for $170
PRV Audio 18SW2000 18" High Power Pro Audio Subwoofer 8 Ohm
New Item
By the way guys , here is this used (but new to me) M-audio interface off of Ebay, you can get these for peanuts right now 😀
It sounds good and Win7 had no problems loading up the drivers for it automatically .... I haven't tried it on the Win Xp box yet (My Akabak machine) ... Those problems i was having with inconsistent audio quality (using the Crown's RCA inputs) are now solved with this M-audio unit , sounds solid! 🙂 ... Hopefully my Dayton mic will also now be fully reliable on this one
..
By the way guys , here is this used (but new to me) M-audio interface off of Ebay, you can get these for peanuts right now 😀
It sounds good and Win7 had no problems loading up the drivers for it automatically .... I haven't tried it on the Win Xp box yet (My Akabak machine) ... Those problems i was having with inconsistent audio quality (using the Crown's RCA inputs) are now solved with this M-audio unit , sounds solid! 🙂 ... Hopefully my Dayton mic will also now be fully reliable on this one
.. An externally hosted image should be here but it was not working when we last tested it.
About that PRV 18
hmmm ...
I wonder why PRV does not provide a voicecoil inductance (Le) figure for that 18" driver?
If someone were really interested in buying one or a few of those i bet we could get someone down at PE to get a measurement for us ..
hmmm ...
I wonder why PRV does not provide a voicecoil inductance (Le) figure for that 18" driver?
If someone were really interested in buying one or a few of those i bet we could get someone down at PE to get a measurement for us ..
Matthew. I have been toying in Akabak but I'm just not quite satisfied with the outcome. Response to ragged or LF to low in amplitude 😕
I have a ? about how to compensate for the K-aperture in multiple parts height, when you increase height in Duct P2 and P3. How does that relate? Or am I looking at this the wrong way?
I have a ? about how to compensate for the K-aperture in multiple parts height, when you increase height in Duct P2 and P3. How does that relate? Or am I looking at this the wrong way?
Ack-My-Back
Sebastian,
Increasing the height of Duct P2 and P3 (Interchamber vent and Freddi-mod) would mean that the front chamber section above the driver would be longer and that requires adding a few more pipe characters before an entry in the last section (as you can see it is already done in the first three entries) of that Akabak code which unfortunately tunes things a little lower , but we can bring the tune back up by shortening the interchamber vent and opening up the front chamber a bit by moving the baffle back further and that is done by reducing the length of P2 and increasing the "HD" measurements in the first section of Aperture code (defines the depth of the front chamber) ...
EXAMPLE: You could add 2.6cm to all of those "HD" entries in the first aperture code section, this would be moving the baffle back by 1 inch and opening up the front chamber by increasing it's internal volume .... FB should shift upward..... Then reduce the length of P2 by the same amount (2.6cm) in order to further shift the FB upward..... Feel free to reduce the length of P2 further if you need to (this length can be removed from the other end of the vent, the rear-chamber end if necessary in the sketch and build) ..
Let me know where your tuning ends up 🙂
by the way , your F0 and F1 lengths should have decreased when you increased the height of P2 and P3 ..
NOTE: Actual response will extend higher than what Akabak shows you (when using Aperture style "D" and "E" )
ANOTHER NOTE: Since the new aperture style "E" is so incredibly simple i might be able to replace the aperture, front chamber and slot sections of the code (the majority of this script) with only a waveguide and a duct , and that would greatly reduce the complexity and size of this script 😀 ... I will have to look into this ..... It would make adjusting the simulations so much easier and more fun! Less hassle
.....
Sebastian,
Increasing the height of Duct P2 and P3 (Interchamber vent and Freddi-mod) would mean that the front chamber section above the driver would be longer and that requires adding a few more pipe characters before an entry in the last section (as you can see it is already done in the first three entries) of that Akabak code which unfortunately tunes things a little lower , but we can bring the tune back up by shortening the interchamber vent and opening up the front chamber a bit by moving the baffle back further and that is done by reducing the length of P2 and increasing the "HD" measurements in the first section of Aperture code (defines the depth of the front chamber) ...
EXAMPLE: You could add 2.6cm to all of those "HD" entries in the first aperture code section, this would be moving the baffle back by 1 inch and opening up the front chamber by increasing it's internal volume .... FB should shift upward..... Then reduce the length of P2 by the same amount (2.6cm) in order to further shift the FB upward..... Feel free to reduce the length of P2 further if you need to (this length can be removed from the other end of the vent, the rear-chamber end if necessary in the sketch and build) ..
Let me know where your tuning ends up 🙂
by the way , your F0 and F1 lengths should have decreased when you increased the height of P2 and P3 ..
NOTE: Actual response will extend higher than what Akabak shows you (when using Aperture style "D" and "E" )
ANOTHER NOTE: Since the new aperture style "E" is so incredibly simple i might be able to replace the aperture, front chamber and slot sections of the code (the majority of this script) with only a waveguide and a duct , and that would greatly reduce the complexity and size of this script 😀 ... I will have to look into this ..... It would make adjusting the simulations so much easier and more fun! Less hassle
.....
can you fudge "E" in hornresp? the Audio Buddy is ok - especially for the $12 I paid 😀 - seen mentions of its phantom voltage ranging from 27 (loaded with one mic) -40vdc
A $12 Audio Buddy is affordable audio companionship
Almost, but not quite, with one more horn segment i could get it even closer ..... The Quick & Dirty HR method is a good way to determine if a driver will work in a Karlflex (in a given box size, and tuning) ..
Great score at $12! 🙂 That voltage sag problem from a lack of Phantom supply current is also something that one of my Lexicon units suffers from, so i don't even bother hooking up condenser microphones to that one (at least not without an external phantom supply), i just use it for playback and that works well 🙂
By the way i did end up having to download the driver pack for this M-Audio interface .... Win7 will load the drivers for playback but doesn't allow access to the pre-amp section in software until you manually load up some drivers ... No big deal, the download is free ..... NOTE: For some reason M-Audio set up the drivers to have the mic-pre monitor enabled which gave me a good scare when first turned phantom power with the mic plugged in .... A nice loud howling feedback eek ! 😱
Almost, but not quite, with one more horn segment i could get it even closer ..... The Quick & Dirty HR method is a good way to determine if a driver will work in a Karlflex (in a given box size, and tuning) ..
Great score at $12! 🙂 That voltage sag problem from a lack of Phantom supply current is also something that one of my Lexicon units suffers from, so i don't even bother hooking up condenser microphones to that one (at least not without an external phantom supply), i just use it for playback and that works well 🙂
By the way i did end up having to download the driver pack for this M-Audio interface .... Win7 will load the drivers for playback but doesn't allow access to the pre-amp section in software until you manually load up some drivers ... No big deal, the download is free ..... NOTE: For some reason M-Audio set up the drivers to have the mic-pre monitor enabled which gave me a good scare when first turned phantom power with the mic plugged in .... A nice loud howling feedback eek ! 😱
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What can a Karlflex do with a 18XL1600? What about 4 of them?
FaitalPRO 18XL1600 18" Neodymium Professional Subwoofer 8 Ohm
FaitalPRO 18XL1600 18" Neodymium Professional Subwoofer 8 Ohm
Faital Pro 18
XRK ,
Nice driver, Uber capable, and a substantial investment for 4 of them ....
They would have outstanding output in some large Tapped Horns of course, but if someone was willing to sacrifice some output to end up with a cabinet that is half the size (and gain some additional bandwidth in the process) , then some scaled up variation of the Karlflex might be an option ....
We would be talking about a 35hz tuned cabinet in the range of 160 liters to 170 liters net internal volume minimum for that particular driver, and the trick would be figuring out how to shoehorn the driver into such a cabinet (it would be great if we have the outer dimensions of a 24" cube, but it might be challenging) ....
Output would be fairly flat 125db in halfspace for one box which is not outrageous but remember this is a tiny box ..... 136db-ish for 4 cabinets in halfspace ... Both sims are just based upon the quick and dirty HR model ..
After i get this version for 12" and 15" drivers finalized then i plan to start working on a version for 18" drivers..
XRK ,
Nice driver, Uber capable, and a substantial investment for 4 of them ....
They would have outstanding output in some large Tapped Horns of course, but if someone was willing to sacrifice some output to end up with a cabinet that is half the size (and gain some additional bandwidth in the process) , then some scaled up variation of the Karlflex might be an option ....
We would be talking about a 35hz tuned cabinet in the range of 160 liters to 170 liters net internal volume minimum for that particular driver, and the trick would be figuring out how to shoehorn the driver into such a cabinet (it would be great if we have the outer dimensions of a 24" cube, but it might be challenging) ....
Output would be fairly flat 125db in halfspace for one box which is not outrageous but remember this is a tiny box ..... 136db-ish for 4 cabinets in halfspace ... Both sims are just based upon the quick and dirty HR model ..
After i get this version for 12" and 15" drivers finalized then i plan to start working on a version for 18" drivers..
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