FYI: BPD 02 series specs are up (1 Viewer)

[Jack Gilvey]

Good question. What is it that we'd change about the Blueprint -03 series, for example?

 

[JimPeitersen]

Perhaps a different voice coil arrangement? Perhaps cosmetic changes? Scott mentioned that metal cone drivers might be a possibility. Anything I am missing?

JP

 

[Jack Gilvey]

A DVC version would be cool, inasmuch as I'm assuming that that would raise Pe, as well as widen wiring options. I've not used metal cones, but I understand they can be more rigid...what do you see as a practical benefit of this (aside from probably looking real cool )?
I think the "holy grail" of sub drivers, at least for me, would be a Tempest with twice the Xmax. I don't know if that's possible with current technology, though. Xmax such as on the -03's requires a stiff suspension, which raises Fs. Raising Mms through mass-loading to lower Fs really only lowers sensitivity in the upper bass, as can be seen in models. Certainly not an expert, but it seems that the necessary sacrifices have been made with the -03's in order to accomodate their prodigious excursion, and it leads me to wonder what else can be done, even if cost is not an object.

 

[Hank Frankenberg]

Anthony, any idea about when the 01 series will be upgraded? 01's going from 24 mm to 36 mm is quite a change, but I hope cost doesn't increase very much. The world needs a best performance/value 10" and 12" for small enclosure applications.

Jack, I agree that there's probably not much improvement available, given the tradeoffs and compromises that BP and Adire and Stryke have already accomplished. Each has concentrated on their chosen design goals. I'm intrigued by low-cost, high-performance drivers like the Tempest, and now that I see this 01 series, they look good too.

 

[DanWiggins]

Jack,

How much Xmax you want? Our new XBL2 motor technology can pretty much give you as much linear Xmag as you want... How about a 15" driver with 30+mm of linear Xmax, and an Fs down around 20 Hz?

Dan Wiggins

Adire Audio

 

[Kyle Richardson]

That would put a big on my face! Damn, I havent even finished my current project and I'm already thinking of an upgrade!
Dan arent you up a little early this morning?
Kyle Richardson
Acoustic Visions

 

[ThomasW]

Interesting new drivers at interesting prices, but look at the Fs. These better handle tons of power since lots of EQ is going to be needed to get them to play low.

 

[Hank Frankenberg]

Thomas, you're talking about the 02 series, right? How 'bout the 01's? The 1201 Fs is 18.51 Hz and the 1001 Fs is 18.78 Hz. Not too shabby and look at the prices!

 

[Brian Bunge]

The 01 specs look similar to ACI's SV10 as far as Fs and Vas. Qts is lower for the 01. The SV10 edges out the current 01 for Xmax, although if the new ones will have 18mm Xmax it will best the SV10 by 2mm.

What it would come down to for me would be enclosure size and the increase in price. Much over $10-$15 more for the 01 and it will be around my price for the SV10.

Brian

 

[Anthony_Gomez]

the new 01's should have 32mmp-p which works out to 16mm...like the sv-10

Thomas, as for handling tons of power, these are more car auto subs..hence the responce.

 

[JimPeitersen]

Good to see Dan (& Adire) represented. The new motor technology looks interesting, but to be brutally honest - the Brahma drivers are expensive. For DIY'ers, the questions becomes one of cost/benefit. Could you get the output of the Brahma series using two or more less expensive drivers? Perhaps as the technology is implemented, the cost per driver will decrease.

JP

 

[Jack Gilvey]

How much Xmax you want? Our new XBL2 motor technology can pretty much give you as much linear Xmag as you want... How about a 15" driver with 30+mm of linear Xmax, and an Fs down around 20 Hz?

I don't have to think all that long about that one, Dan...OK. Got any preliminary specs we can play with?

 

[Brian Bunge]

Geez, Dan is such a tease! That driver might make me part with my 1803!
Brian

 

[DanWiggins]

Kyle,
yeah, up early... It happens some times!
Jim,
Well, if you go by the 71% BL (about 10% THD from the motor), then a Tempest is about equal to a Brahma 12, in terms of linear displacement overall. HOWEVER, if you go by 90% BL (about 1% THD from the motor), then you need nearly 2 Tempests to get the same displacement level...
The beauty of the technology is that BL just does not fall off with excursion, until you're at your absolute limits. Means MUCH lower distortion at a given excursion (up to 3-4 times lower). So even if you have the same "Xmax" number, you still have much lower distortion up to that point. The flatter the BL curve, the lower the distortion, meaning you can run higher SPLs before THD becomes objectionable, even if the nominal Xmax values are the same.
Jack,
Seriously - how much do you want? Would 30-35mm be good enough? More?
But on a bigger question, what would the "Jack Gilvey Special" look like? I'm interested in what you would see as a good set of T/S parameters and design goals... Let's have some fun! How about a custom driver for a specific application - the Ultimate Home Theater Subwoofer. Choose an alignment (some mondo-wicked vented thing), and let's see what we can - as a group - dream up. All the T/S parameters are up for consideration. Power handling? Assume 5 kW RMS is the upper limit. Sd/Xmax? How much do you want (can do up to 18" diameter drivers).
As far as what can be done, there will be a few [Darth Vader voice from the destruction of Tatooine] "demonstrations of our power" [/Darth Vader] coming soon!
Brian,
I'm working on it!
Dan Wiggins
Adire Audio

 

[Jerry Parker]

Im not Jack Gilvey, but....
I think a driver that could handle 5kW power all day RMS Pure sine waves would be nice. At least 18" in diameter, and would have usable frequency response up to 100hz. Aluminum cone and rubber surround. Another thing about the surround... It should not be so FAT that the cone area is impeded. It should have a profile where the surround is VERY tall, but not very wide. Therefore SD is not lost. Huge, wide, dual triple, or even QUAD progressive spyders (if possible). Underhung Motor design. DVC or Quad VC so that mulitple amps can be used (You pretty much have to) An FS of sub 20hz would be nice as well. And last but not least, it must have a massive XMAX of 60mm peak to peak linear, and an Xmag/Xsus (whichever comes first) of 100mm, and at that 100mm BL still be at at least 50 percent.
Now I know what you guys are thinking. That boy is crazy!!! But hear me out. I just would like to know, what from the above features are able to be produced in a new speaker? Are there still technological limitations? Are the subwoofers of 20 years from now going to be THAT much better because of new technologies/materials available? I know that back in the 1970's they didnt have drivers that had xmaxes of 50mm!!! Thanks for any input!

 

[Jack Gilvey]

Im not Jack Gilvey, but....

Lucky man...

 

[DanWiggins]

Jack Gilvey posted:

Quote:

Aww, shucks... That's what running a few hundred thousand models and fully spec'ing out the driver goals before it's designed will do. I think we nailed it pretty good, too, to create a "generic" driver that works well in most applications.
Dan Wiggins
Adire Audio

 

[Jeffrey Noel]

Whatever monster sub you build, lets try to keep it within my college student budget!!

 

[Jack Gilvey]

So, a Tempest/Shiva with 30+mm of Xmax? That can be done without any real effort - it's trivial to get Xmax any more. But what else would you (or anyone else) want to see?

Well, since my professed "holy grail" has been granted in the course of one morning, I'm at something of a loss.
I mean, I love the way those drivers model. If I were going to change something, I'd like smaller boxes for given alignments (almost certainly using PR's) and more output/Vd/Pe, without losing much sensitivity. It'd be nice to have a driver that just can't be bottomed, even when at Xsus/Xmech. Some kind of "soft-bottoming" arrangement.
A driver optimised for IB use might be fun, if limited in market. Although, as I've stated before, a Tempest or Shiva (possibly incorporating RDO) comes pretty damn close to ideal, more excursion always being nice.
While we're at it, I'd also like a true full-range driver, flat from 80Hz-20kHz, kind of an improved Diatone, with lots of sensitivity. A nice,flat 8-ohm impedance would be in order, of course.

 

[Kyle Richardson]

My thoughts are something in the lines of the driver mentioned with a vas that works optimally in about 3cu ft. Sensitivity isnt too terribly important since high power amps are fairly inexpensive now days and I agree a Fs around 19-20 would be ideal.
I also agree with Jack that a driver that would be very hard to bottom would be ideal as well (as I think 30mm would do). Single spider is fine, just as you stated Dan...XBL takes care of the need for more.
One suggestion, since we're talking about a mean driver here we need to make it look nice too. I could care less about a crome basket and magnet assy since it will be hidden in a box but a metal cone would look nice. I realize it may change alot of TS parameters since it will weigh more but its a thought. No graphics are needed on the dust cap...this is for home usage so we want it to look classy at the same time.
Kyle -I see a home version of the Brahma taking place here- Richardson
Acoustic Visions