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wrt above comparative narrative,

in the design stage of my custom dual driver VBSS,

from @LTD02 - this:I'm not really coming up any good idea for a cab that will fit in your space and really crush it from 40hz up. This is a pair of PA460 drivers in a 10 cubic footer tuned to 38hz. That should provide pretty decent performance from 40hz-100hz. This is with 1000 watts total. Each driver is only rated for 500 watts. 130db is pretty loud though. :)

For the space I had, yeah, HE NAILED IT!

His other 2 designs I've built the SUBMAXIMUS and LOWARHORNS really crush that lower octave and below . . easily

In initial listening to standard "test" audio selections, while checking on driver displacement, 5 x 18"ers working in harmony , while non seemed to be working too hard, there was a ton more visceral feel, to say the least, so some load taken off the Fusion 15's, > bumped the xo from 40 to 80.
 
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Would you be able to share the max output graph for this system?

the overhang on the driver is 6mm. using that as the excursion limit gives the black line.
discussions with mtg90 and driver measurement indicate that the useful excursion is somewhere around 9.5mm or possibly a little more. that gives the red line.
two pi space. no room gain. 6 subs.


 

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it was asked how this system would compare to some of the other drivers mention.


1w response of a handful of systems (at prices on p.e. at the moment)


6 x pa460 (red) $540
3 x pa465 (green) $660
2 x um18 (black) $558
2 x 460ho (blue) $524

all in the same cabs ~11cf tuned to ~17.5hz. i don't like the way the pa465 (green) is modeling, but ymmv.




max output at the usable excursion of the pa460, um18 (the um may have a hair more excursion left, but it is power limited at 2kw), 460ho, and xmax for the 465 (I've not seen this driver measured physically so i don't know how xmax was calculated).

anyway, the pa460 system gets away with a 3000dsp
the 460ho and um18 would need to step up to the 6000dsp or a pair of bridged 3000dsp if you want remote turn on and no thump without doing the internal relay mod to the 6000.


 

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it was asked how this system would compare to some of the other drivers mention.


1w response of a handful of systems (at prices on p.e. at the moment)


6 x pa460 (red) $540
3 x pa465 (green) $660
2 x um18 (black) $558
2 x 460ho (blue) $524

all in the same cabs ~11cf tuned to ~17.5hz. i don't like the way the pa465 (green) is modeling, but ymmv.

max output at the usable excursion of the pa460, um18 (the um may have a hair more excursion left, but it is power limited at 2kw), 460ho, and xmax for the 465 (I've not seen this driver measured physically so i don't know how xmax was calculated).

anyway, the pa460 system gets away with a 3000dsp
the 460ho and um18 would need to step up to the 6000dsp or a pair of bridged 3000dsp if you want remote turn on and no thump without doing the internal relay mod to the 6000.
Well, if your talking 6 drivers in a modest HT setting, I would assume you would make the UM-18s sealed.
But it all depends on application and user needs.

LTD, what if you modeled the pa465 at a tuning of 25-35hz? I was just looking at the parameters of that driver and figured it might perform better tuned closer to Fs?
Seems weird that Dayton would manufacture (being that it costs over twice as much - pa460 > pa465) a driver that basically performs the same as pa460 but with added power handling which isn't as exciting as it looks because it's 4 dB less sensitive.
 

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Well, if your talking 6 drivers in a modest HT setting, I would assume you would make the UM-18s sealed.
...

there are lots of ways to make bass. as you know, sealed is the least efficient, so it is a poor choice where space is available and budgets are tight. 6 x UM and the amps to power them is out of the budget here.


LTD, what if you modeled the pa465 at a tuning of 25-35hz? I was just looking at the parameters of that driver and figured it might perform better tuned closer to Fs?

same problem, the driver is underdamped. the motor doesn't seem to have enough power to overcome the moving mass and the suspension stiffness. it might work for some applications, but I can't recommend it based on what I've seen so far.


Seems weird that Dayton would manufacture (being that it costs over twice as much - pa460 > pa465) a driver that basically performs the same as pa460 but with added power handling which isn't as exciting as it looks because it's 4 dB less sensitive.

the typical pro audio cab might be something around 7 cubic feet tuned to around 38hz. in such a cab, the underdamped response will give a 5db rise in spl around 50hz (97db 1w1m) which would bring it up about the same sensitivity as the 460, but with more xmax and more power handling. I don't think it would sound as good because of the falling top end, but for folks looking for a few more db from their sub, it may have a place.
 

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there are lots of ways to make bass. as you know, sealed is the least efficient, so it is a poor choice where space is available and budgets are tight. 6 x UM and the amps to power them is out of the budget here.

same problem, the driver is underdamped. the motor doesn't seem to have enough power to overcome the moving mass and the suspension stiffness. it might work for some applications, but I can't recommend it based on what I've seen so far.

the typical pro audio cab might be something around 7 cubic feet tuned to around 38hz. in such a cab, the underdamped response will give a 5db rise in spl around 50hz (97db 1w1m) which would bring it up about the same sensitivity as the 460, but with more xmax and more power handling. I don't think it would sound as good because of the falling top end, but for folks looking for a few more db from their sub, it may have a place.
Well, I assume that 6 pa465s would also be out of budget, but the OP was just asking about them.
And yes, I understand the cost of the amps would be more expensive (3000DSP > 6000DSP on the UM-18s)

Interesting driver (pa465) for double the price....Thanks for the comment.
 
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the overhang on the driver is 6mm. using that as the excursion limit gives the black line.
discussions with mtg90 and driver measurement indicate that the useful excursion is somewhere around 9.5mm or possibly a little more. that gives the red line.
two pi space. no room gain. 6 subs.


The numbers above 50hz are HUGE!
 

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Added bonus is that you can add 2 more, and not need another amp.


Sent from my iPhone using Tapatalk
Yes, an inkuke 3000dsp is 2 ohm stable on each channel. That particular speaker is 8ohms, so you can 4 subs off of each side for a 2ohm load vs the 2.6ish you're getting with 3 subs on each side.



Too bad it's only six... Hateful Eight


 

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The Dirty Harry build...

[after an audition, remote control in hand] "I know what you're thinking. Did he build six subs or only five? Well, to tell you the truth, in all this excitement I kind of lost track myself. But being as this is an LTD build, one of the most respected names in the forum, and would blow your socks clean off, you've got to ask yourself a question: Do I feel lucky? [finger touches volume control] Well, do ya, punk?"
 

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Discussion Starter · #33 ·
The Dirty Harry build...

[after an audition, remote control in hand] "I know what you're thinking. Did he build six subs or only five? Well, to tell you the truth, in all this excitement I kind of lost track myself. But being as this is an LTD build, one of the most respected names in the forum, and would blow your socks clean off, you've got to ask yourself a question: Do I feel lucky? [finger touches volume control] Well, do ya, punk?"
lol! Still can't believe I'm building 6 haha. Luckily I enjoy this stuff very much. As long as I take my time and don't push too fast to get it done yesterday it will be great.
 

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lol! Still can't believe I'm building 6 haha. Luckily I enjoy this stuff very much. As long as I take my time and don't push too fast to get it done yesterday it will be great.
While I'm not an entirely big fan of cliche quotes (I disagree with most of them :p), the classic "slow and steady wins the race" usually leads to be more true when DIY comes to mind.
Taking the time to plan and lay everything out, gather the correct kind and amount of supplies, and all other things usually leads to fewer mistakes and an overall better finished and satisfying product.

Enjoy the build. It's always satisfying to surf around at completed subs and seeing how much money you saved yourself going the DIY route.
 
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Discussion Starter · #35 ·
While I'm not an entirely big fan of cliche quotes (I disagree with most of them :p), the classic "slow and steady wins the race" usually leads to be more true when DIY comes to mind.
Taking the time to plan and lay everything out, gather the correct kind and amount of supplies, and all other things usually leads to fewer mistakes and an overall better finished and satisfying product.

Enjoy the build. It's always satisfying to surf around at completed subs and seeing how much money you saved yourself going the DIY route.
I'm new enough to the game (or I should say back again after many years) that I prob don't know how much I'm saving. I need to look around at that.
 

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Discussion Starter · #36 · (Edited)
Wish I could do a poll for names that have been suggested... I'll pick one soon; they're all creative and hilarious.

Still working on the first 'prototype' enclosure: Tonight I will install the braces and glue the baffles together.

Looking ahead at tomorrow night it will finally be time to cut the driver hole in. LTD suggest a surface mount for ease of construction which I am fine with:

1. Shall I screw the baffles together and cut the hole out (jigsaw) both baffles at the same time?
2. Any videos/tutorials on best way to lay out the hole and actually cut it in? - a bit nervous to cut this thing in; not sure how much tolerance I'll have.
3. I have foam (both 1.5 inch and 2.5 tk) but LTD suggested a pillow. Pillow sounds easier but I'm not partial to either. Anyone use pillows to dampen?
4. I am fairly certain the enclosure is tight but should I seal to be sure and what product would you all recommend?

Pics coming soon!
 

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http://www.data-bass.com/data?page=content&id=79


http://www.hometheatershack.com/for...ojects/18349-tc-1000-sonosubs.html#post164576
(later he conclude that only a single pillow located at the center of the cab was sufficient to knock out resonances)


the easy way to find the center is to draw a diagonal from each opposing corner. they will form an "X" marking the center of the panel. then use your compass or whatever tool to scribe the cutout.


the cabs need to be air tight (other than the port). how that is achieved doesn't really matter, just make sure it is so. :)
 

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Discussion Starter · #38 ·
http://www.data-bass.com/data?page=content&id=79


http://www.hometheatershack.com/for...ojects/18349-tc-1000-sonosubs.html#post164576
(later he conclude that only a single pillow located at the center of the cab was sufficient to knock out resonances)


the easy way to find the center is to draw a diagonal from each opposing corner. they will form an "X" marking the center of the panel. then use your compass or whatever tool to scribe the cutout.


the cabs need to be air tight (other than the port). how that is achieved doesn't really matter, just make sure it is so. :)
will do! I don't have a compass so I need to get creative. first enclosure is slow but the next few will be much quicker. I have a nail gun now which will help alot!!
 

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No compass? Drive a small nail at your dead-center point (where the lines in the "X" meet). Tie a string around the nail. Let out enough string to get to the radius (half the diameter) of your circle. Tie pencil to string so that the point of the pencil is exactly at that radius point. Admittedly, this is tricky, but easily doable. Keeping string taut, draw a circle. Win!

It is better for the hole to be a tiny bit too small than oversize. You can sand the circle open with 60-grit paper until the driver fits, but you can't put wood back into a cutout too large.
 

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Discussion Starter · #40 ·
Followed your advice and done! Fits like a glove thank you!

Being the novice that I am a few of my cuts aren't perfect; specifically I have one vertical brace that is 1/16 (atleast) too short from front to back. Ltd had mentioned to me that I should use a construction adhesive called pl Premium for boards that are a bit too short.

How exactly does PL premium work? Does this stuff actually expand or is it more the consistency of a caulk and therefore able to be built up to bridge gaps where glue would not. Any application tips appreciated. I'm concerned that that vertical brace is too short and therefore potentially not able to adequately reinforce the walls as designed...
 

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