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Old 26th March 2007, 11:30 PM   #111
R. Jamm is offline R. Jamm  United States
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Default EnABLE pattern?

BudP

Ive been following this thread and am in the process of building the Mamboni speaker system -Im still waiting on parts and time (just got back from vacation) to finish it. Correct me if Im wrong--your idea is to stencil in rectangular patterns (EnABLE pattern) with some type of acrylic model paint using a calligraphy pen on or near the top and bottom of the speaker cone.

- Also, you stated that this process should be used on the cabinet itself. Where would you place it?
- Is there an EnABLE pattern straight line stencil for this?
- Are the triangles the same size no matter what size the drivers are?
- Would this work on a cylinder cabinet like the one mamboni used (post #32)
- Is the EnABLE pattern different for tweeters? What tweeters would this work on?
- Do you have stencil for the different sizes woofer?
- Would the constant movement of the cone over time make the acrylic come off?
- Would you be sharing more information on how to get and use the EnABLE pattern and what are the best speakers this process will work on?
- Do you have any pictures of pass projects that you could share?

You stated that you have a conventional system that easily outperforms the Ohm F in all categories. Could you explain more and share the plans on how to make them?

Thanks,
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Old 27th March 2007, 01:16 AM   #112
BudP is offline BudP  United States
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Default Whew.....

R Jamm,

You have the general plan correct and the pens have been my only means of applying the EnABL process in the past.

c2cthomas and I are collaborating on a stenciling method to replace the pen applied method for many applications. These stencil's will be available, in some DIY usable fashion, pretty quickly. We have plans and methods and even media trials in the works. If we are successfull you will have stencils that are designed for whatever woofer you are going to use.

This is planned with the thought of using Mamboni's felt triangles on the inside of the cone. I am pretty certain that this combo will be ultimately superior to the EnABL process alone. When both sides of a cone are treated with EnABL the cone becomes very transparent to back wave signals, emitting right through the cone and into the listening area. The EnABL process enforces a phase and time coherent wave structure to emitted information and that sort of energy is very good at remaining coherent, regardless of obstructions.

Using the Mamboni process right where he uses it now will help eliminate that possibility and still provide the needed "infinite" cone edge termination to the back side of the driver that allows the EnABL process to completely control the front side information emissions.

Just like the EnABL pattern blocks the Mamboni triangles probably should increase and decrease with the size of the cone they are applied to. I do not know if Mamboni has a rigorous analysis of this size change and I am not at all sure how much change is correct. We will all find out as we go along. I would personally scale the triangles in size, up or down, from his proven concept size found on the 10" woofers he is advocating using.

I would place the linear patten of EnABL blocks down the length of the tube, on opposite sides with a vector between the opposite lines at right angles to the listening area. This will attach all information expression from the tubes to this plane and will likely provide you with the leading edge of the perceived sound field too. I do this with ordinary cabinets, placing the pattern lines vertically, in the middle of the front to back dimension of, and down, all four of the sides. This helps to eliminate the entire speaker system as a perceivable sound source and in my system the speakers are sonically invisible regardless of where you sit, just like Ohm F's are.

I have never had the pattern made with acrylic paint delaminate or shed. I have had the conformal coat acrylic delaminate from the polypropylene surface of the Dynavox woofers in two half round areas, one on each woofer and about a 1/4" diameter. The coating has not come off nor has it altered the sound. It just lifted enough to show at these two places. This is the only event like this I have witnessed and because of it I now "tooth" the surface of plastic cones with 1000 grit sandpaper before applying the pattern and conformal coating. I do not think this will be needed on any other cone, dome, flat ribbon or horn flare material.

All speakers are the best for EnABL use. The process does NOT alter the speakers inherent qualities. As far as engineering concerns go the speaker just acts more like a theoretically perfect model would. I have applied the process to every type of speaker made and find that, while all of them share a clarity of detail, a hugeness and coherence of projected sound field, and, an uncanny rendition of musical colors and musician imposed emphasis, some manufacturers provide products that are just more interesting than others. Vifa, peerless, dynavox, seas, morrel and many others manufacturers drivers have been treated.

From that sort of list, my current system uses:

a 9.375" dynavox polycone woofer with a huge voice coil and a dis-assemble-able basket structure, that allows treatment on both sides of the entire cone surface.

a 6" dia Vifa dome midrange, with the inner perforated metal dome removed, the backing plate holes cut to one hole, the size of the magnet structure pass through hole. A very small back chamber (.4 liter as opposed to the 1.6 liter suggested) made from an ABS pipe end cap, stuffed with long fiber natural cotton that also extends up through the center magnet hole to form a small dome, trapped by a large opening plastic wire mesh.

two Radio Shack/Linnaeum polycarbonate leaf tweeters

a single Pioneer piezo film, half of a can shaped super tweeter, with the fine mesh grill removed.

All of the drivers and their mounting plate surfaces on the visible side have been treated with both the EnABL pattern and conformal coat material. Except for the Pioneer driver all of them have also had the EnABL pattern and conformal coating applied to the backside of the drivers. The pattern is not noticeable unless you look very closely but the very shiny surface of the conformal coat is quite noticeable.

On the Linnaeum and Pioneer tweeters only the pattern areas have been coated with the conformal coating. The dynavox woofer has a VERY thick coating, at least 10 mils, of the conformal coating just to construct a semblance of a boundary layer that will interact with the surrounding air. Otherwise it would be very clear and very dead sounding. As of now it matches the "speed" of the rest of the drivers exactly.

The system is sort of flat from 33 Hz to what ever the cut off for the Pioneer is. I am not as concerned with fractional octave to octave flatness as I am with phase coherence at the crossover points of 800 Hz, 4 kHz and a 0.22 mfd induced slope for the Pioneer tweeter. The entire tweeter assembly is impedance matched through a transformer, the design and manufacture of that sort of audio device is my livelihood, with a 2.8 db cut in turns matching ratio.

I can post a finished picture if anyone is interested, but it is not really impressive, until you turn them on and hear an orchestra embedded 50 feet into the back wall and from edge to edge and floor to ceiling of the room, without any hint of Hi Fi sound characteristic and seemingly infinite detail. Very nice to listen to, so long as I am not experimenting with new audio transformers that are not fully charged, or new DIY Litz wire audio cables, or the eternally demented "electron traps" I have been applying to the ground sides of all of my components, since discovering their characteristics.

Bud
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Old 27th March 2007, 03:06 AM   #113
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R Jamm

I have my materials on order and slated to arrive next week - around 2 April. I'm using Heil AMT2 tweeters so my construction is going to be a bit different than the original mamboni design. I'm also aiming at a tweeter height of 36 inches so I have switched to 14" Sonotube with a 28 inch height. This was discussed in some earlier threads. Because Sonotube comes in 12 ft. lengths I'm going to have enough for 4 tubes to play around with - as well as an extra Pioneer speaker. I'll be trying a few different test configurations - one original speaker via mamboni method - but using the Heil tweeter - perhaps to be replaced by a B&G NEO 8 at a later date. I'll try the B&G because people can still purchase that tweeter for a reasonable cost and the Heils can only be had by ordering them from Germany - at around $600.00 each. On the base units I'm going to make one as specified by mamboni and stuff it to around 50% with acoustastuff. Another one I want to try is what the Sonotube sub-woofer builders do with some dampening of the walls with auto-body undercoat and batting around the inside of the tube plus some acoustastuff - filled to taste. The 1st Pioneer 10 inch unit will receive the mamboni treatment only and the second will be a combo of mamboni triangles on the inside of the cone and Bud P's EnABL pattern on the cone outside (rear of the speaker - basket side) both on the top near the VC and on the bottom near the surround. I'm also considering an EnABLE pattern around the circumference of the Pioneer's baffle but I need to consult with BudP on this as it places the pattern in the horizontal plane and I'm not sure if that will lead to problems or not. But what the heck - it's an extra tube and it might be fun to try it out just for the fun of it.

I have some material on order that BudP and I want to try out before we report on it. I don't mean to be keeping anything a big secret - I'm just trying to keep from getting people all hot and bothered over something that might not work out. BudP's method is proven to work - as long as you have good eyes and steady hands. At my age I'm afraid that neither my eyesight or steadiness of hand are what they used to be - so I'm motivated to develop an easy to do method - if possible. Seeing as how we are both starting a build let's keep in touch with ideas and problems.

BTW - cash spent to date (not including tax or shipping) around $185.00 for two speakers. Still need to get some minor stuff - so looks like I'll be into around $200.00 or so -

and yes - I will post progress photo's and listening impressions.

Cheers
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Old 29th March 2007, 09:24 PM   #114
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Most of my parts have arrived (but not all) and the 1st hunk of Sonotube has been cut. Pioneer 10 inch speakers are here and getting ready for the mamboni treatment.

Did a bit of a "dry fit" to check size of units - looks good for my target tweeter height of 36 inches plus or minus.

Photo of "ruff" dry fit.

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Old 29th March 2007, 11:49 PM   #115
BudP is offline BudP  United States
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C2Cthomas,

We're waiting...........

I have attached a pic of how to treat a typical Walsh dome style tweeter and deflection plate with the EnABL process. Had to go digging in really old patent papers to find it too....

Mamboni

Our processes are being talked over, in another thread, quite unrelated to this one and by one of the most famous of all DIY proponents.

http://www.diyaudio.com/forums/showt...threadid=98969

We should join in and drag ole Thomas himself with us.

Bud
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Old 30th March 2007, 02:05 AM   #116
mamboni is offline mamboni  United States
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Quote:
Originally posted by c2cthomas
Most of my parts have arrived (but not all) and the 1st hunk of Sonotube has been cut. Pioneer 10 inch speakers are here and getting ready for the mamboni treatment.

Did a bit of a "dry fit" to check size of units - looks good for my target tweeter height of 36 inches plus or minus.

Photo of "ruff" dry fit.

Thomas:

Even as mockups, I love the look! the squat wide tube with the inverted woofer, tall ribbon tweeter and wide baffles gives it an avante garde look, like "Krell Loudspeakers" from outer space. Have you done any listening?
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Old 30th March 2007, 02:07 AM   #117
mamboni is offline mamboni  United States
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Quote:
Originally posted by BudP
C2Cthomas,

We're waiting...........

I have attached a pic of how to treat a typical Walsh dome style tweeter and deflection plate with the EnABL process. Had to go digging in really old patent papers to find it too....

Mamboni

Our processes are being talked over, in another thread, quite unrelated to this one and by one of the most famous of all DIY proponents.

http://www.diyaudio.com/forums/showt...threadid=98969

We should join in and drag ole Thomas himself with us.

Bud
Bud

Very interesting mod! Thanks for the tip on the other thread - I'm reading though it - Lynn Olsen has been around this business for a long time and is something of an audio-Yoda.
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Old 30th March 2007, 02:42 AM   #118
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Hi Mamboni and BudP - and everyone else!

The "wide baffle" was just some scrap wood on which to place the Pioneer 10 inch for the 1st dry fit for sizing. The actual speaker will look like your Walsh 5 remakes - except that mine will have the Heil tweeter (in this version).

I'm cutting up felt for your Mamboni pattern right after I finish this post. BTW I'm using bright red felt so it shows up better in the assembly photo's - and I am taking photo's as I go.

I did happen to see a certain distinguished person mention BudP's EnABL pattern in another thread - Yea for BudP!

Oh BudP - I have a copy of your patent on hand - and I'm moving at a deliberate and careful speed - remember - this is my 1st DIY speaker effort -

Gotta go "Mamboin" some speakers. :
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Old 30th March 2007, 01:44 PM   #119
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Did not get as far as I wanted last night - it took a while to measure the Pioneer and determine the placement of the Mamboni triangles. For those interested - I measured on the inside of the mounting bracket circumference and came up with 6 centimeters for triangle centers on this make and model of particular speaker. I have applied the triangles as per the Mamboni design. I have some other ideas as to size and placement - but the good Doctor M has already played with several versions of his design so I'm not going to screw around at this point. Things are already complex enough with the combination of the Mamboni design and the next unit which will use this as well as BudP's EnABL pattern on the "backside" of the speaker cone. Of course because we are using a Walsh type of transducer the "backside" winds up being used as the "radiating side" when assembled - so when I say "backside" I am referring to the cone surface facing the speaker basket.

Going to dissect the speaker dome today after running my spousal unit to Huntsville. So the bad news is that I'll be gone for several hours. The good news is that I'll be alone and free to "play" all I want for a couple of days.

Photo of last nights progress - the second speaker should take much less time to do now that I have gone through the learning curve.
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Old 30th March 2007, 01:56 PM   #120
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photo of how I made my measurements for the Mamboni triangles. Using inches came out sort of odd so I switched over to cm/mm's and it works out nicely at 6 cm per division. I considered using an odd number of triangles so I could tell my friends that I have and "odd" speaker - and then watch their eyes glaze over as I explained just exactly why!

BTW - use of a cloth type tape works well for this measurement. My trusty Stanly 25 ft. metal tape I use around the house just didn't get the job done - no cm's on it!!
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