EnABL project, Audio Nirvana Super 12

[hajj]

After a Pm exchange with BudP concerning the project, I took by his advice, and am posting it here for anyone interested to contribute (even a link to certain post in a thread) and hopefully as some kind of an information thread where people planning on EnABL'ing their drivers would find the information they're seeking.

Please bear through this long post, as I try to make things as clear as possible.

I have a pair of Audio Nirvana Super 12 stamped frame speakers that have been in my system for a bit more than a year now.
I feel that these speakers have reached their improvement limits concerning break-in, yet they still retain some shrillness and edginess in the upper frequencies (i'm guessing starting at 2.5 Khz and up, with bumps along the way), and the sound tends to "stick" to the drivers.

This issue has led me to seek other drivers for my setup, or even a different approach altogether (horns, O/B drivers with relatively high x-max and Qts, even planars...)
So, unless i can find a way to make the AN drivers sound better, they're going out anyway.
Since the EnABL treatment is by all means a cheap one, I decided to give these drivers one last chance, and hopefully along the way learn a thing or two about the process.....

I know there are lots of threads concerning Fostex drivers, and the specificity of their banana pulp paper cones (damar, conforming coat, etc..)
But many of these steps seems to be non-mandatory ones (and sometimes detrimental) for other types of drivers, while some other treatment steps are needed only on drivers with bigger diameters than available from Fostex (tacky acrylic glue to the cone's backside, etc...)

The AN Super 12 is phase-plugged, whizzer coned driver with a relatively large voice coil (1.5 inch, approx 3.8cm), so it's a different beast altogether compared to the majority of the drivers being EnABL'ed.


First off, the tentative list of materials to be used, so far i've compiled the following:

• Damar
• ModgePodge (Puzzlecoat)
• Poly Scale
• Ever tacky acrylic glue
• MicroGloss

As you can see, the problem with the above list is that most of these materials are referred to by brand name, as for those living outside North America (as is my case), most of these are rather hard to come by.
I am aware of the EnABL Kit being sold, but alternative options are always a good thing to have

• For example, i've read somewhere that the Tamiya acrylic paints used for model cars is a good substitute to Polyscale as long as it's flat and not glossy, because flat paint has a higher solids content and is thus denser. If anyone can confirm this, that would be great.
  
• As for Damar used to draw the "trifoil pattern", it seems that the only real testing was carried by Dave of planet10 on the Fostex Fe207/Fe206 drivers and I can't figure if this will yield any result on my specific drivers which have a relatively high density/very tough paper cone.
  
• The puzzlecoat is also a tricky step, as some advocate laying it first, then the EnABL pattern on top, while in other cases, EnABL pattern applied directly on the cone seems to be enough. Would regular PVA wood glue be an option?
  
• Microgloss, are there any alternatives?

I guess this is the first part of the process, getting the right materials.
Next is tools
Followed by Process, Techniques and tweaks.
This is going to be a long process, and I hope an interesting one for the forum members.

Dave and Bud, your input will be most valuable.

For those of you that have survived the long post, here are some pics of the driver with some measurements.

[Dave Jones]

Damar varnish is easy to make. Required are a glass or metal sealed container, some cheese cloth or equivalent, damar resin crystals, and high quality (triple distilled) turpentine. I use it for oil paintings. It is not compatible with acrylics.

[Ty_Bower]

I'm curious to see how this turns out.

[planet10]

The damar was/is used on the FE12xe drivers specifically to deal with a resonance in those cones. Not applicable, without a lot of research, to any other cones.

The mod podge (PVA) acts as a stabilizing surface to put the EnABL on. I use it on almost all non-coated paper cones. I will be using it on the AN Super 8 that have been patiently waiting for treatment.

dave

[scott wurcer]

Originally Posted by planet10

The mod podge (PVA) acts as a stabilizing surface to put the EnABL on.
dave

Dave, I use Mod podge by the gallon for crafts and don't find it's behavior identical to "pure" PVA especially with respect to clouding after multicoats or water contact post drying. PLAID actually makes a version that never clouds even after total water immersion. I'm not a chemist so I don't know what the differences are.

[hebrer]

hajj,
I cannot tell how happy I was to discover this new thread you started.
I have recently finished my back-loaded horns with AN 10" cast frame drivers (see attached photo) and am sure I need to try the EnABL process. I have previously used Planet10's enabled Fostex FE127eN and the quality of the sound with EnABL is addictive.
I have found the following links somewhat relevant to the topic you started:

Picasa Web Albums - Bud - Audio Nirvana...

EnABL - Listening impressions & techniques

Anything you post on your progress in EnABLing AN12" or any further relevant information/instructions will be much appreciated.
Peter

[planet10]

Originally Posted by scott wurcer

Dave, I use Mod podge by the gallon for crafts and don't find it's behavior identical to "pure" PVA especially with respect to clouding after multicoats or water contact post drying

Or remains as flexible. I tried lots of things before settling on ModPodge (and a number of variations of that were tried too).

dave

[hajj]

Ok, so Damar seems to be off the list. Great, one less thing to worry about
What about the acrylic paint used for the pattern? and the microgloss on top?
btw, just for fun, i went and applied an EnABL pattern on the outer metal rim of one driver using transparent tape.
I'll report with results (if any) as soon as i have it mounted back.
Thanks all for your input, keep'em coming guys.
Any bit of help is needed here
Regards
Nick

[BudP]

I have been discussing another problematical driver with Gary Pimm. The Emminenece Beta 8. He sent some test impulses of the driver, already EnABL'd, to midge0 for wavelet analysis. What they were looking at was what impact occurred from placing a very dense industrial felt on the inside of the metal basket legs, with appropriate cuts to clear surround and spider. I have attached pics. Take a look in the upper mid frequency areas. Gary says that this reduction in ghosting,or "hall of mirrors" reflection, is quite noticeable. The CSD plot of both of these treated driver tests looks like that of a good ribbon tweeter.

So, I have added another material, to take the place of the removed Damar varnish. I will see if I can obtain a brand name for this mylar backed felt, so that Ed can offer it with the rest of the kit. And really, Ed's kit is the way to go, just get all of the stuff from him. Besides, you need the pen holding wand to use on the tap test you are going to learn to do, to analyze where exactly these patterns need to be applied. Which brings up a whole bunch of questions about other tools you are going to need, to do these drivers properly, something they do deserve.

Bud

[hajj]

I have sent Ed a PM concerning the Kit
As for the felt application; if i understood it correctly, it's a way or deadening the reflections occuring from the basket legs, right?
If so, my guess is it would yield interesting results for the Stamped steel basket AN super12 i have on two fronts.
First, any reduction in ringing of these legs is a major plus
Second, the basket legs are relatively quite large, rendering a reduction in reflections potentially very noticeable.