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Which drivers for highly custom, small enclosure?

jhaider

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The Dayton RSS265HE is also a great option when it comes to T/S for small enclosures but the Seas has proven linear excursion. You could also fit two of the notch larger Daytons (RSS315HO-4) in 40 liters with a Q of 0.6 . The SB has a great track record but the excursion is pretty nonlinear...

The mk II Dayton Reference looks very good on paper - larger voice coils and high excursion, with inductance kept in check. I’ve never used them. They’re 20% off today, with a good return policy if they don’t work out, so may be worth serious consideration.

That said, FWIW I tried the previous Ref 265 (Velodyne SC10 cabinets) in my old desktop system, and ended up going back to the OG Peerless XLS10s (Triad Bronze “in wall” subwoofers pushed against the wall under my desk) they were supposed to replace. I don’t think there should have been any difference but for whatever reason (I don’t remember why now) I just liked the old ones better and went back to them.

Also one more word about modeling. When I model a closed box today, I only look at one thing: can it reach theoretical full excursion with the power I plan to use in that box. That’s a crude measure to be sure, but gets you in the ballpark of being able to make use of all your power and all your excursion.

As the board insists on having a downfire (sagging) config.
???

Times the solution doesn't come from in the obvious ;-) Cost of no concern? Go for BMS neo drivers or JBL's XBL^2 p/a woofers.

BMS makes high performance drivers that are also beautiful (the back end of the 8N519 is a work of art - makes me want to try them as midbasses in OB) but are hard to source in the US. I also don’t know if they have a long throw 10 or 12. Those are midbass sizes in BMS’s market. Maybe you know of one?

I don’t think JBL made a 10” or 12” PA sub (could be wrong) but differential drive (not XBL - JBL never used that) woofers are quite deep. The old car audio JBL W10GTi it (basically their pro audio differential drive platform with a heavy cone and rubber surround) might have been a good fit, but they’re long out of production. If one’s hunting unicorns then Aurasound NS10-794-4a or NS12-794-4- would be the ones to get anyway.
 

jhaider

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I see no essential difference.

They are totally different.

XBL uses a single voice coil in a single thick top-plate with a notch in it to form two gaps.

IMG_1949.jpeg

Source: https://audioxpress.com/article/test-bench-the-bwx-6502-midbass-from-misco-s-bold-north-audio-line

The advantage here is it’s relatively inexpensive compared to other “exotic” motor designs. The disadvantage is lower power handling.


Differential drive (18Sound’s name for the same concept is “tetracoil”) uses twin coils separated in space on a common former, wound in opposite directions, and each operating in their own gap.
1691267068818.jpeg

Source: https://www.eighteensound.it/en/technologies/ttc-tetracoil-double-voice-coil/

The advantages are much better power handling (more coil operating in more steel), some degree of inductance cancellation due to the opposed windings. The disadvantages are higher cost (twice the coils, more steel) and greater motor depth.
 

MAB

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I see no essential difference. But as the o/p seems to be as financially potent as it might get, better to leave him with commercial consultants.
=> Billy Nomates "Supermarket Sweeps"
What a bass can do ...
Why do you have to be such a jerk to everybody?

You got all your facts wrong in an argument with the very much more knowledgeable, experienced, and helpful @jhaider
Then you turn to an ad hominem on the thread's OP.

You appear to have no practical experience at all. Just nonsense. And really denigrating to other members.

I recommend you leave.
 

AdamG

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Why do you have to be such a jerk to everybody?

You got all your facts wrong in an argument with the very much more knowledgeable, experienced, and helpful @jhaider
Then you turn to an ad hominem on the thread's OP.

You appear to have no practical experience at all. Just nonsense. And really denigrating to other members.

I recommend you leave.
He won’t be responding to you in this thread again. ;)
 
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suttondesign

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Turns out, SEAS has a terrific 11” driver, but you can’t get one for love or money. Seems perfect for my application. Wonder what’s going on?
 

Bach

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This is not a reaction nore advice, within the mentioned limitations, but about the chararcteristics of the LX521:
- Open-baffle, dipolar radiator, < 20 Hz to 20 kHz.
- Response -3 dB at 30 Hz (Q < 0.5) on ground plane, free-field.
 

mcdn

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This is not a reaction nore advice, within the mentioned limitations, but about the chararcteristics of the LX521:
- Open-baffle, dipolar radiator, < 20 Hz to 20 kHz.
- Response -3 dB at 30 Hz (Q < 0.5) on ground plane, free-field.
It really isn’t good for below 30Hz. I have a 30Hz LR4 high pass on mine to stop them bottoming out on deep bass. They do sound fantastic though.
 

Bach

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It really isn’t good for below 30Hz. I have a 30Hz LR4 high pass on mine to stop them bottoming out on deep bass. They do sound fantastic though.
So, did you abstinate on bass below 30? If no, what subwoofer did you add to your setup?
 

mcdn

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So, did you abstinate on bass below 30? If no, what subwoofer did you add to your setup?
The filter corner is at 30Hz, so I am getting output down to 20Hz, just a bit reduced. I haven’t added any subs due to space restrictions, and honestly for music, including electronica/dance, it’s not an issue.
 

Bach

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The filter corner is at 30Hz, so I am getting output down to 20Hz, just a bit reduced. I haven’t added any subs due to space restrictions, and honestly for music, including electronica/dance, it’s not an issue.
A corner of 30 Hz: does that mean the -3dB point?
How much attenuation Is there at 20 Hz? A bit is rather vague.
When the argument for any subs is lack of space, then why adding the argument of it being no issue?
 

mcdn

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A corner of 30 Hz: does that mean the -3dB point?
How much attenuation Is there at 20 Hz? A bit is rather vague.
When the argument for any subs is lack of space, then why adding the argument of it being no issue?
A Linkwitz-Riley filter is -6dB at the corner frequency, and a 4th order one drops off at 24dB/octave. See https://en.wikipedia.org/wiki/Linkwitz–Riley_filter
 

mcdn

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A corner of 30 Hz: does that mean the -3dB point?
How much attenuation Is there at 20 Hz? A bit is rather vague.
When the argument for any subs is lack of space, then why adding the argument of it being no issue?
More output below 30Hz would be welcome for movies. I don’t find it an issue for music. In-room response is always hugely variable anyway, which is why I use room correction
 
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suttondesign

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A corner of 30 Hz: does that mean the -3dB point?
How much attenuation Is there at 20 Hz? A bit is rather vague.
When the argument for any subs is lack of space, then why adding the argument of it being no issue?
my layperson understanding:

because the linkwitz woofers are not in a box, they face little pressure in a room. they just keep going until they exceed their maximum excursion. because I listen to music and movies with deep bass content, I have to apply a filter to limit spl below 30hz.

a subwoofer in a box does not pressurize the room “box” to achieve low bass. it just pressurizes the box in which it is mounted, so it it much harder to exceed max excursion. but also requires much more power.
 

jhaider

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Turns out, SEAS has a terrific 11” driver, but you can’t get one for love or money. Seems perfect for my application. Wonder what’s going on?
Which one are you looking at? I've never seen an 11" Seas.

Are you thinking about the ScanSpeak Rev 28? I vaguely recall seeing something about Scan discontinuing some Rev subwoofer drivers. Maybe in Voice Coil? This may be one of them. My guess is that except for the "high enders" who need the visual distinction of the Rev mounting flange and dull grey cone, the Scan Disco 30 is will give similar performance for 1/2 - 1/3 the price. The Scan Disco sub drivers are really really good and often overlooked. They’re basically slightly improved XLS. I think Scan erred branding them in the budget line. These and the 10F neo midranges are a cut above the rest of the Disco line IMO.

That said, there are some European distributors that claim to have stock. I have not personally imported from any of those shops though, so no recommendations pro or con.
 
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suttondesign

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Which one are you looking at? I've never seen an 11" Seas.

Are you thinking about the ScanSpeak Rev 28? I vaguely recall seeing something about Scan discontinuing some Rev subwoofer drivers. Maybe in Voice Coil? This may be one of them. My guess is that except for the "high enders" who need the visual distinction of the Rev mounting flange and dull grey cone, the Scan Disco 30 is will give similar performance for 1/2 - 1/3 the price. The Scan Disco sub drivers are really really good and often overlooked. They’re basically slightly improved XLS. I think Scan erred branding them in the budget line. These and the 10F neo midranges are a cut above the rest of the Disco line IMO.

That said, there are some European distributors that claim to have stock. I have not personally imported from any of those shops though, so no recommendations pro or con.
scan 28w/4878. the scan 12” disco is also out of stock.
 

Bach

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my layperson understanding:

because the linkwitz woofers are not in a box, they face little pressure in a room. they just keep going until they exceed their maximum excursion. because I listen to music and movies with deep bass content, I have to apply a filter to limit spl below 30hz.

a subwoofer in a box does not pressurize the room “box” to achieve low bass. it just pressurizes the box in which it is mounted, so it it much harder to exceed max excursion. but also requires much more power
My layperson says: read the answer on the site of The Linkwitz on: Do I need to add a subwoofer to reproduce the lowest bass frequencies?
 

MAB

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Here are the excursions of an L26ROY in various sealed enclosures, infinite baffle a random ported enclosure.


my layperson understanding:

because the linkwitz woofers are not in a box, they face little pressure in a room. they just keep going until they exceed their maximum excursion. because I listen to music and movies with deep bass content, I have to apply a filter to limit spl below 30hz.

a subwoofer in a box does not pressurize the room “box” to achieve low bass. it just pressurizes the box in which it is mounted, so it it much harder to exceed max excursion. but also requires much more power.

Yes, the box has an effect. It certainly limits the excursion below the resonance frequency of the system. The port limits the motion even more than the cabinet in the sealed alignment at the system's tuning frequency! As you suggest, the infinite baffle will have larger excursion at low frequency than sealed, but ported actually have larger excursion below the system frequency.
Here is a simulation of the excursion of an L26ROY at 250W in 10, 20, 40, and 80 liter sealed cabinets, plus Infinite Baffle, and Ported.
1691361831350.png


These sealed alignments will end up with higher excursion once you add EQ. 6dB is double the excursion.
 
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suttondesign

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Here are the excursions of an L26ROY in various sealed enclosures, infinite baffle a random ported enclosure.
A driver quite similar to the SEAS L26ROY is the 10" CSS, and CSS shows similar response and excursion curves for various sealed enclosures. (https://www.css-audio.com/sdx10-curves).

I did a lot of modeling today. It's so illuminating!

At this point, I'm pretty much down to one downward-firing driver in a smallish box with good EQ and lots of power. I've narrowed down to the 12" and 10" CSS, the 10" SEAS L26ROY, and the 12" Scan-Speak 30W/4558T (as jhaider notes, a relative bargain). Using just one driver mounted at bottom allows me to do my large-book hocus-pocus and make these disappear completely.

I am very much alive to jhaider's warning about sag, but I also have a living room doubling as a media room, and a serious WAF. She acquiesces to the LX521.4 -- actually says she thinks they look cool. Subwoofer boxes do not look cool. Big books do.

I'll post pics once I start building the boxes. I'm using 1" baltic birch, dominos and pocket screws, and a bunch of stuffing.
 

Waxx

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I would in your case probally put 2 x Dayton RS265HO-4 in a box and eq them to what you want with dsp. No driver will go that low without eq. It fits in small spaces. Even a 10L cabinet could be good that way, on it's own it won't go low, but it will take eq very well. If you do dual opposed woofer cabinets, the distortion will also be less, and if you build a few like that (at least 2 cabinets so in total 4 woofers) you can go over 100dB at 20Hz before running into the xmax limit. The xmax limit is not the max volume, but is where distortion start to rise fast as the excursion of the cone is not linear anymore.

And tha Seas is very orverpriced in the actual market, that Dayton cost a lot less and is a better subwoofer in my opinion. Don't get me wrong, Seas makes great drivers and the L26Roy is, but similar quality drivers from SB, Dayton and a few others cost a lot less...
 
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