Design suggestions using 6.5” Peerless NPT-11-078-1

[grimberg]

During BAF 2008 Jack Hidley generously handed out some 6.5” Peerless NPT-11-078-1 drivers, the subwoofer used in the NHT Super Two and Super Sub loudspeakers. I brought some home with me and would like to use them in a project. I am asking for design ideas and am sure other people will be interested as several attendees took home the same driver.
On Jack Hidley’s personal page at http://home.comcast.net/~jhidley/ there is a link to an Excel spreadsheet containing T/S parameters and related information for this and other drivers. Here is what it says about the NPT-11-078-1.

Part # : npt-11-078-1
Used in NHT models : Super Sub Super 2
Brand : Peerless
Size : 6.5"
Shielded : No
Basket : Steel
Cone material : Laminated poly
Re (Ohms) : 4.84
Fs (Hz) : 51.7
Qms : 2.738
Qes: 0.584
Qts: 0.481
Vas (l): 16.10
Cms (m/N): 0.000543
Mms (g): 17.4
Diameter (mm): 136
BL (N/A): 6.85
SPL (2.83V): 87.64
Zmax (Ohms): 27.6
Sd (m^2): 0.01453
Xmax (mm): 4.9
Hg (mm): 6.0
Hvc (mm): 15.7
Former material : Aluminum
# of coil layers : 2
Coil diameter (mm) : 32

[grimberg]

One idea could be a design similar to what Jack demonstrated at the event, using six Peerless woofers, a midrange and a tweeter in a sealed cabinet built out of concrete form.
You can see them in the last picture posted by Wavebourn at:

http://www.diyaudio.com/forums/showt...14#post1636814

[willick]

Grimberg,

You didn't happen to grab enough of these drivers that you could spare a pair did you? I need 2 to repair my actual SuperTwos. Do you have a friend that might have?

Thanks in advance...
-John

see the thread I pathetically started here: Burning Amp - free NHT woofers..?

[PeteMcK]

they look good down to the low 40s in 30L tuned to 43Hz, down to low 30s -3dB EBS in 40L tuned to 33Hz, double volumes for 2 drivers...

[grimberg]

Could you tell me what modeling software you use?

[GM]

If you want to wow your friends with big SPL down well below Fs from a little driver, a tapped horn will do it if you don't mind a big cab.

GM

[grimberg]

Originally posted by GM
If you want to wow your friends with big SPL down well below Fs from a little driver, a tapped horn will do it if you don't mind a big cab.

GM

I would like to try it. Where can I find more information?

[GM]

This long thread has the vast majority of TH knowledge along with many designs and simming programs info and I recommend you browse it all if you're truly interested in designing your own and DLing Hornresp if you have a Windoze machine to work through permutations of existing designs using your driver's specs to find what you consider the best trade-off between gain BW and size.

GM

[Andersonix]

Can anyone point us toward a frequency response curve for these NPT-11-078-1 Peerless drivers (Peerless model 850397)? I'd like to know what low-passing at about 4200Hz would look like.