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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Subwoofer Forum => Topic started by: Caleb Dueck on October 13, 2020, 04:06:19 pm

Title: Neo drivers for LAB Sub?
Post by: Caleb Dueck on October 13, 2020, 04:06:19 pm
After looking at the LAB sub plans again, and the drivers, I have one question. 

The LAB 12 drivers have ferrite magnets, and were specified specifically for the LAB sub.  Are there any newer drivers, with Neo magnets, that have 'close enough' T/S parameters overall but higher BL and power handling - to provide higher performance overall? 

What started this - the first time I heard nearly all the subwoofers side by side from another manufacturer, I noticed that some models sounded less sloppy than others, and they fit neatly into two groups of subs.  It happened that the more sloppy models happened to all have ferrite magnets, and the better sounding ones all had neo magnets. 

Or is the only logical upgrade from the LAB sub something like the DBH218?
Title: Re: Neo drivers for LAB Sub?
Post by: Tim Weaver on October 13, 2020, 05:15:51 pm
I'm sure Ivan will be along shortly to set you straight, but I doubt that any Neo pro driver will be anywhere close to the Lab12.

The Lab12 has way more in common with car stereo boom-boom drivers than any other pro driver on the market. It was specifically created and built just for that horn.

There may be some car audio neo subs that could get close, but you'll have to do your own T-S measurements. I wouldn't rust published data from the car stereo crowd.
Title: Re: Neo drivers for LAB Sub?
Post by: Steve M Smith on October 14, 2020, 04:21:37 am
There may be some car audio neo subs that could get close, but you'll have to do your own T-S measurements. I wouldn't rust published data from the car stereo crowd.


Especially when you see some of their claims for output power, then work out what current that would need to be on a 12v supply!


Steve.
Title: Re: Neo drivers for LAB Sub?
Post by: Helge A Bentsen on October 14, 2020, 05:48:53 am
I always wanted to do something the other way around, stick a Lab12 in a existing factory design.
EAW LA400 comes to mind. I'm sure it's a "Really Bad Idea" and I don't have either sub or driver available to experiment with.
Title: Re: Neo drivers for LAB Sub?
Post by: Doug Fowler on October 14, 2020, 01:45:46 pm
I'm sure Ivan will be along shortly to set you straight, but I doubt that any Neo pro driver will be anywhere close to the Lab12.

The Lab12 has way more in common with car stereo boom-boom drivers than any other pro driver on the market. It was specifically created and built just for that horn.

There may be some car audio neo subs that could get close, but you'll have to do your own T-S measurements. I wouldn't rust published data from the car stereo crowd.

It would not be the first time TD used a a car stereo woof.
Title: Re: Neo drivers for LAB Sub?
Post by: Ivan Beaver on October 14, 2020, 02:56:13 pm
It would not be the first time TD used a a car stereo woof.
And not the last-----------

But they have to be specific woofers for a very specific usage.

The drivers and cabinets are designed to be used together.
Title: Re: Neo drivers for LAB Sub?
Post by: Ivan Beaver on October 14, 2020, 02:59:47 pm
I'm sure Ivan will be along shortly to set you straight, but I doubt that any Neo pro driver will be anywhere close to the Lab12.

The Lab12 has way more in common with car stereo boom-boom drivers than any other pro driver on the market. It was specifically created and built just for that horn.

There may be some car audio neo subs that could get close, but you'll have to do your own T-S measurements. I wouldn't rust published data from the car stereo crowd.
There may be some neo high powered drivers that would work fine, or possibly better.  Sometimes the T-S parameters can "cancel each other out".  Meaning that the overall result will be fine, even if some of the parameters are very different.

Of course this takes a proper model and time to find such drivers.

But, no, I don't have any suggestions.
Title: Re: Neo drivers for LAB Sub?
Post by: Doug Fowler on October 14, 2020, 03:25:24 pm
And not the last-----------

But they have to be specific woofers for a very specific usage.

The drivers and cabinets are designed to be used together.

I can name 2 :-)
Title: Re: Neo drivers for LAB Sub?
Post by: Tim McCulloch on October 14, 2020, 05:05:26 pm
I can name 2 :-)

"One" and "Two".  /nudge, wink
Title: Re: Neo drivers for LAB Sub?
Post by: Art Welter on October 14, 2020, 08:05:25 pm
After looking at the LAB sub plans again, and the drivers, I have one question. 

The LAB 12 drivers have ferrite magnets, and were specified specifically for the LAB sub.  Are there any newer drivers, with Neo magnets, that have 'close enough' T/S parameters overall but higher BL and power handling - to provide higher performance overall?   

Or is the only logical upgrade from the LAB sub something like the DBH218?
The practice of bolting more slabs of the same old magnet together can increase excursion by a lot, but Bl is still weak compared to what can be done with neodymium. Back when Eminence put the LAB 12 together, they weren't using neo. The weaker BL gives that "slump" in response between Fc and the upper end.

Using what looks like a pair of (neo)BC 18SW115 in the DBH218 gives more excursion, more Bl, almost double the cone area, as well as way better cooling in the same S-4 size bin as the LAB horn. The split path still allows about the same path length/Fc as the LABhorn.  A double "W" bin :^).

With neo providing enough magnetic force to push even 21" drivers to far more excursion than the old Lab 12, there are dozens of models from various companies to choose from that can provide far higher performance overall than the LAB 12.

That said, the M-force concept of using a fixed coil and lightweight moving magnet is really attractive when making the "step up" with larger drivers, as long as we are spending other people's money in a time when few in the business are making much ;^).

Art
Title: Re: Neo drivers for LAB Sub?
Post by: Caleb Dueck on October 16, 2020, 02:04:46 am
I'm not curious about max SPL per cubic ft.  My assumption is that a pair of 21", powerful, high excursion drivers, specifically designed for a specific horn - would do that. 

My question, which Ivan answered, was - within the parameters of the existing LAB sub, are there any currently known drivers that would perform better. 

Title: Re: Neo drivers for LAB Sub?
Post by: Ivan Beaver on October 16, 2020, 11:22:05 am
I'm not curious about max SPL per cubic ft.  My assumption is that a pair of 21", powerful, high excursion drivers, specifically designed for a specific horn - would do that. 

My question, which Ivan answered, was - within the parameters of the existing LAB sub, are there any currently known drivers that would perform better.
Of course the "proper" way would be to build a model of the cabinet and then test various drivers.

Tom may or may not still have the model.  But the time to play with various drivers is a different issue.  More important things going on ya know.
Title: Re: Neo drivers for LAB Sub?
Post by: Art Welter on October 16, 2020, 03:58:45 pm
My question, which Ivan answered, was - within the parameters of the existing LAB sub, are there any currently known drivers that would perform better.
Caleb,

If you want to pursue that "yes" answer further, you can try putting other driver's TS parameters into the Hornresp simulation program, a lot easier to work than the AKABAK program Tom used..

The attachment simulation model is pretty close to the inputs required, though Hornresp has gone through a number of changes since this one was done, so may look a little different now.

Art
Title: Re: Neo drivers for LAB Sub?
Post by: Tim Hite on October 16, 2020, 10:20:52 pm
It happened that the more sloppy models happened to all have ferrite magnets, and the better sounding ones all had neo magnets. 

It probably also so happened that the better sounding subs were also higher end subs and they had neo magnets because neo is more expensive than ferrite. Probably better engineered boxes with fewer internal resonances and more powerful amplifiers and maybe better DSP.  Neo has a higher magnetic flux density than ferrite, so it's lighter for a given application.
Title: Re: Neo drivers for LAB Sub?
Post by: Caleb Dueck on October 17, 2020, 05:13:42 pm
It probably also so happened that the better sounding subs were also higher end subs and they had neo magnets because neo is more expensive than ferrite. Probably better engineered boxes with fewer internal resonances and more powerful amplifiers and maybe better DSP.  Neo has a higher magnetic flux density than ferrite, so it's lighter for a given application.

Could be, but the price differences weren't much, not much more than the cost of drivers themselves.  When asked about it, their response was that it was due in large part to the magnet power.  The difference wasn't based on families of subwoofers, or simple price point; it was solely an audible difference that happened to line up with magnet material. 

Art - if I was fluent in Hornresp and subwoofer design theory, I'd have just done the work myself by now ;)  Also asking since there was a chance Ivan or Tom may have happened on some free time over the years (ha!) and done this, or someone else with a broader range of accessibility to drivers, may have done this. 
Title: Re: Neo drivers for LAB Sub?
Post by: Marcel de Graaf on October 27, 2020, 02:15:06 pm
Best Caleb,

I have been using my labhorns for more than 15 years. Everyone who`s has build and used it will say the labhorn
is an incredible clean sounding low frequency system. There are 2 primairy reason why the labhorn sound that good.

1.) The driver and cabinet a knit together to one system. The combination cabinet / T&S paramaters are the right
     match for a high efficiency.
2.) The second reason is the design of the lab12 driver alone. The cone is incredibly rigid and stif. TD and Eminence
     have designed a wonderfull driver. A driver that alone is responsible for just clean and low frequencies, without the
     distortion effects, that other would quote as punch.

The later i have seen with my Contrabass subwoofers. Also in this design, besides the high efficiency vs cabinet size, the coness are stiff and riged. There is no room for distortion effects. This makes this system so enjoyable to listen to. At first sight you would say the contrabasses should sound sloppy and slow due to the high mass radiators, but the contrary is true.   

My point here is, there is more to look into only at the T&S parameters. The lab12 driver is almost designed 20 years ago and till today there is no substitute. My opinion in this is that driver manufactures are missing here a very important key aspect.
(of course drivers go way up in motor strenght and power ratings).

Greetings, Marcel
Title: Re: Neo drivers for LAB Sub?
Post by: Ivan Beaver on October 27, 2020, 03:32:57 pm
Best Caleb,

I have been using my labhorns for more than 15 years. Everyone who`s has build and used it will say the labhorn
is an incredible clean sounding low frequency system. There are 2 primairy reason why the labhorn sound that good.

1.) The driver and cabinet a knit together to one system. The combination cabinet / T&S paramaters are the right
     match for a high efficiency.
2.) The second reason is the design of the lab12 driver alone. The cone is incredibly rigid and stif. TD and Eminence
     have designed a wonderfull driver. A driver that alone is responsible for just clean and low frequencies, without the
     distortion effects, that other would quote as punch.

The later i have seen with my Contrabass subwoofers. Also in this design, besides the high efficiency vs cabinet size, the coness are stiff and riged. There is no room for distortion effects. This makes this system so enjoyable to listen to. At first sight you would say the contrabasses should sound sloppy and slow due to the high mass radiators, but the contrary is true.   

My point here is, there is more to look into only at the T&S parameters. The lab12 driver is almost designed 20 years ago and till today there is no substitute. My opinion in this is that driver manufactures are missing here a very important key aspect.
(of course drivers go way up in motor strenght and power ratings).

Greetings, Marcel
The contrabass cones are NOT normal.  They started out as normal, but then they were dipped in epoxy/acetone to get them REALLY stiff and hard.  I think you can stand on the cone and not have it collapse.
Title: Re: Neo drivers for LAB Sub?
Post by: Jeff Bankston on November 16, 2020, 01:45:39 am
"One" and "Two".  /nudge, wink
Buckle my shoe