XKi - X's ab initio Karlson 6th Order Bandpass

Hello X

Would Fane's Sovereign 10 work decently with an XKi ? - could it share the alignment you made for SN10C?

or is it better in a traditional K alignment? I'm hoping it cam provide some sense of "weight" on drum beats without losing
too much head resonance overtone information, so can stand alone at times and not be too embarrassing.

gap height = 10mm, coil height =18mm so pretty good xmax tradeoff vs motor size - rated "98dB"

Def_Driver 'Fane Sovereign Pro10" | Fane 300W rated speaker with 4mm VC overhang, Qts = 0.32, 2.5" VC, 56oz ferrite magnet
Sd=378 cm2
Fs=58 Hz
Mms=37g
Qms=6.08
Qes=0.34
Re=5.7 ohm
BL=15.3 T/m
Le=1.68mH
Vas=41L

It lacks the steep rise of some 10's above 1K -hope that's
more a blessing than a negative

Here's the info on the SN10C XKi

GqKP0ep.png



(here's an LMS graph of Eminence's Alpha 10, showing a typical rise http://www.rackeys.gr/images/thumbs/0006036.jpg )

Aw1G6Ca.jpg
 
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Founder of XSA-Labs
Joined 2012
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For the W5-2143 XKi, make the box 10in deep x 8in wide x 12in tall (all inside dims) with a 8in wide x 0.5in gap vent that is 5.75in long. The front driver mount panel setback is 4in deep to provide a 20% front chamber volume and 80% rear chamber volume. Make the wings following usual K style with the edges of K-aperture curves just touching the driver surround when viewed from the front. Line all surfaces adjacent to back of driver with felt, as well as front chamber sides and back side of K aperture to reduce first reflections.
 
Fostex 206En

OK, so I took a stab...I'd like to try this build and I'd be happy to share if I can get some feedback on some of the measurements because I'm not sure I've figured this out correctly.

I'm assuming the volume ratio does not take into account the vent space or the space the speaker takes up...since you all decided the height of the triangle was 4 and the base was 15.

The things that most puzzle me:

- The angle of the speaker in the cabinet. Is it just "shallow enough to fit" ORRR the long side where the speaker is mounted should be the length of the hole necessary for the speaker plus 2 inches, in which case the triangle would be 9x8x4 with another triangle that is 7x4x8...?
- The set back of the edge of the vent from the front face... 1.5?
- The length the vent wraps down around

I couldn't discern a ratio based on your other drawings as to where to place that 4 inch line. So here's what I have, am I way off?

Also, it seems like the front curtain always starts two inches from the top, but I'm not clear on how the curve scales outward. Help me, I studied business and my math is terrible!

Doc - Sep 30 2017 - 1-25 PM.jpg
 
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Founder of XSA-Labs
Joined 2012
Paid Member
The angled panel where the driver mounts is simply made based on two things:

1. It needs to be big enough to fit the driver bezel and tall enough that when it angles back the magnet or basket doesn't touch the bottom.

2. The angle is set such that the vertex is a certain depth back to provide the required front chamber volume. The volume is the triangular area in cross section x width. The area of the triangle is 1/2 the area of a rectangle of the same setback. So to get 20% front volume in a 10in deep cabinet, the depth has to be double the percentage or 40% deep for example. 40% of 10in is 4in.

So the interaction of a panel big enough for the bezel and the 4in depth defines the front chamber geometry.

The vent is simple linear length of vent, leave room at front for it to breathe.

Aperture always has some material st top as matter of strength to allow making it one piece bit also to make sure vent airflow is directed across the driver face before exiting to enforce 6th order bandpass behavior and provide added cone movement control.
 
Aperture always has some material st top as matter of strength to allow making it one piece bit also to make sure vent airflow is directed across the driver face before exiting to enforce 6th order bandpass behavior and provide added cone movement control.

OK, so really the only thing that matters is the volume ratio, and the aperture in the front should generally follow the shape in the design... but there's not any real specific measurement?
 
on another forum, there was a bass reflex build for Dayton's PA460-8 18 inch - about 9 cubic foot internal volume and tuned low.

I tried to compare it to a 1.2X Acoustic Control K-coupler which would be about K15's bulk https://i.imgur.com/iijQCDc.jpg

I bet there's a good XKi alignment for that woofer which would maintain good punch, go "low enough" (maybe 40 or a bit lower) and allow a box that's not as tall as K15 as the poster of that project wants to use his helper woofer box as a stand for his Fane 12" fullrange.
 
hey X - might there be a better XKi solution for my 15pzb40 then putting it into a Karlflex or 115BK?

whether MMJ's kluge for 115BK = "real" = ?? - curve wise and
Z peak wise, it seems to concur pretty well - not sure about spl (maybe ?) as its showing
some advantage over the offset driver K box.

I have a 115BK but not sure if physically whether a 15pzb40 would
fit due to frame size and driver depth. 115BK is only 12" deep inside between the aperture and back panel.

Sine drum tuning charts show a 50Hz tuning for a 24" diameter kick drum, it would be nice
to have response flat to about that point. A lot of kicks, particular in past time, seem tuned higher with the large
floor tom being the lowest "note"

Def_Driver "B&C 15PZB40" |15 inch woofer Xmax 8MM Qts 0.29
Sd=855cm2
Fs=43Hz
MMs=123g
Qms=7.4
Qes=0.3
Re=5.3
BL=24.3Tm
Le=2.4mH
Vas=112L


inuYDeq.jpg


although results may be "mellow", I think this woofer could reach a 1" format K-tube
whereas my 15tbx40 (like 15tbx100) drops off after 1K.
KfIbzbS.jpg


Scaling 115BK by 1.2X gives
GixTyI5.jpg
 
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new life for old vifa 5" M13SG-09-08?

X- I have some speakers that were a madisound suggested theater combo in the 90's and they never impressed me much musically. But the vifa woofers had a great reputation and I'd like to try them in an XKi to see if new life can be breathed into them. Can you suggest an alignment for one 5" per box?
Thanks.

5" woofer VIFA M13SG-09-08, vc height 10mm, gap height 6mm, nom pwr 35W
Sd=80cm
fs=54 Hz
Mms=6.5 g
QMs=1.5
Qes=0.46
Qts 0.35
Re=5.6
BL=5.2Tm
Le=0.7mH
Vas=12L
 
Founder of XSA-Labs
Joined 2012
Paid Member
X- I have some speakers that were a madisound suggested theater combo in the 90's and they never impressed me much musically. But the vifa woofers had a great reputation and I'd like to try them in an XKi to see if new life can be breathed into them. Can you suggest an alignment for one 5" per box?
Thanks.

5" woofer VIFA M13SG-09-08, vc height 10mm, gap height 6mm, nom pwr 35W
Sd=80cm
fs=54 Hz
Mms=6.5 g
QMs=1.5
Qes=0.46
Qts 0.35
Re=5.6
BL=5.2Tm
Le=0.7mH
Vas=12L

Hi Bonjonno,

I just ran a simulation and this driver can make a nice XKi. Try making a 7in wide box x 12in tall x 9in deep. Pleasing proportions, no? That's about 12.4liter internal, once you subtract the vent and driver volumes you will be at about 12 liters design goal. Make the angled driver mounting board angled back so the setback from front to the vertex is 3.6in. Make the vent 0.50in deep by 7.0in wide (width of box) and extend it back 7.5in. You mayneed to wrap the vent around the corner in order to give clearance to the front of about 1in spacing between vent opening and front K aperture. This will give you an F3 freq if 55Hz and 90dB sensitvity. It will sound quite good on kick drums. You can mount one of these low profile 1in silk dome tweeters from Dayton in a small hole cutout on the aperture (offset) to one side of the wings (or right in middle above the aperture vertex if you prefer).

Dayton Audio ND25FN-4 1" Silk Dome Neodymium Tweeter Element 4 Ohm

The woofer has a natural roll-off at 2kHz so let's use that as the crossover for the tweeter. Just put a 24uF (two 47uF electrolytics - back to back in bipolar confg should be close enough, by pass with 0.47uF filmcap) and add about 3ohm to 5ohm (adjust to taste) series resistor to pad down the tweeter by about -5dB. This will give you a very natural sounding and time accurate 1st order XO. If you want to improve the performance of the XO a bit more, try adding a series 0.5mH air core for the woofer. This will reduce power sent to the woofer voice coils above 2kHz. Something like this should work:

Dayton Audio 0.50mH 18 AWG Perfect Layer Inductor Crossover Coil

Here is response of the woofer before baffle step loss of about -5dB. So it should be an 85dB sensitive overall system:

attachment.php


Note that these are very rough passive crossovers from off-the-top-of-my-head, so it may not be perfect, but should sound quite decent.

If you choose to mount the tweeter in a central hole in the middle at the top of the K aperture board, a good name as you suggest is "XKiClops". :D

I hope you build it.

Cheers,
X
 

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Founder of XSA-Labs
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here's the little Karflex - is there an XKi alignment for the same/similar bulk?

would there be too much coloration introduced by the relatively small aperture?


t1AXwaC.jpg

Hi Freddi,
This is mostly a sub-woofer alignment so I think coloration was not a consideration. Using full range is not advised as it would definitely, be colored. But maybe mid-bass up to 200Hz is OK?
X