EnABL Processes

[planet10]

Originally posted by marce
My appologies for it taking so long, I am snowed under at the moment with PCB's and building the CC's and dont seem to have any spare minutes.

no worries, these things take as long as they take.

Was interested to see the use of grok, in relation to EnABL, a strange verb in a stranger context,

Very well done twist of phrase (for those not knowing what grok means, read "Stranger in a Strange Land" by R Heinlein.

would the difference be apparent between untreeted FE166's and treated FE207's.

Without really knowing for sure, i'm going to say a qualified yes. Your drivers will be far more than EnABLed thou. You can use them as a template to step-by-step mod the FE166s.

And with all the other Fostex in your neck of the woods you should be able to get a handle on what is happening (and hopefully cause a few draws to drop)

dave

[Bas Horneman]

This Friday, room 1128, shortly after 6pm. I hope there is no shooting though.

Oops...I'm off by about a week..

[Zen Mod]

Originally posted by Yunick
I'm on my way to try this on Eminence Alpha-6

please look HERE for pic's...

Bud............... can you look here

and write few words here or there

TIA

[BudP]

Zen,

Looks like very good workmanship.

Now, you need to put a dot in the middle of those central block rings. The dot should be paint first and then, when dry, a drop of PVA (white wood glue or speaker surround to frame glue).

This PVA dot is going to enforce maximum lateral dispersion for highs.

The end result will be that, as you move from an angle that allows you to just look into the cone, all the way to the voice coil, all the way across to the other side of that cone described arc, there will not be any hot spots or any cone specific location clues, even directly in front of the dome. All sound will seem to arise from behind the driver and will be coherent to that sound field, without ever seeming to come from the driver, at all regardless of your angle to the cone.

You use the gloss to enhance this performance by using between 1 to 3 times as much on the cone as on the dome. You are correct to listen before applying the gloss. If the bare treated cone already has no hot spots, then a 50% coating of gloss on dome and cone may be all you need.

Another 50% coating on the cone will not harm matters, but may cause a "tight" sense to the sound until break in is done. Any more will provide a very hard and somehow edged sound that some folks like, but has little to do with reproducing music.

Minimum application and careful listening, to understand what the first coat has provided, is needed here. I always listen to increasingly "dense" music, until I either run out of torture tracks or the music suddenly gets corrupted in politeness.

This corruption will get down to some very small issues. The difference between a pair of soprano's and an alto horn being three voices or swirled up into one, is a useful marker here. Piano's embedded in a violin wash are also excellent torture. If the piano sounds sick or flat, but is still quite distinct from the violins, you need a couple of Electron Pools, not more gloss.

When the corruption no longer occurs, I stop applying gloss coat, and this has always been just enough.

You are proceeding exactly as I would, with an unknown driver. Just take tiny steps from here on, listen carefully and learn to hear what "politeness" might mean from treated speakers.

Bud

[dlneubec]

Has anyone experimented with the EnABL process on more rigid cone materials, like aluminum or titanium cones? How about smaller midrange metal cones or domes?

Is it beneficial for ones that only oeprate over several octaves, as in a typical 3-way?

[marce]

try around post 104

[BudP]

dlneubec,

Metal cone drivers are where EnABL started, Ohm F Walsh drivers were the first location the patterns were developed on. Titanium and aluminum and then paper.

Titanium works very well with just painted block rows. Aluminum usually needs a coat of gloss and even then the alloy may be such that the systemic resonance cannot be completely controlled.

The benefit that EnABL patterns offer are not confined to any particular pass band or type of driver. Domes respond extremely well to patterning, but you must use extreme caution when applying gloss as it is easy to get significantly greater output from them. Likely a combination of phase normalization and overall efficiency. This is especially true for silk dome tweeters. and to a lesser degree dome mid range drivers.

Bass drivers all loose their rumble, become very tuneful, cease exciting room resonance nodes and tend to use the entire house as their front load chamber. Wives and daughters in other rooms become agitated much more quickly. Sons are drawn by the siren sounds. It is also not uncommon for them to cease moving, except to complete a pressure wave of very long duration. especially if they are in a tuned, back side loading arrangement. They really are no longer piston devices, in their coupling to ambient air.

In a multi way system you do need to treat the entire front baffle and ideally around all discontinuities. With these caveats taken care of, a multi speaker system can be sonically equivalent to the very best single full range drivers, in character and specificity of instruments in a sound field, sound field dimensions and often better in dynamic range.

Bud

[dlneubec]

Hi Bud,

Thanks for the reply. If you don't mind speculating a bit, how would you treat something like this omni project I just completed?

Where would you start for most bang for the buck? Would you do the up and down firing midwoofers and their baffles (crossed at about 1560hz)? What about the tweeter baffle? Before or after chamfers? How about the front subwoofer baffle (cross at ~180hz, 20:1 tapered TL, 70")?

I'd appreciate any thoughts you might have.

[planet10]

Those are cool looking (how do they sound?)... an awful lot of surfaces to do... you could be at it for awhile. After doing all the drivers... my guess that structure in the middle, then the midbass baffles would have the most benefit. Bud?

dave

[BudP]

dlneubec

Really lovely workmanship and a delight to look at too.

I am going to assume that the top chamber has a driver equivalent to the middle chamber? Is there another woofer in the top of the bass cabinet? And, another tweeter firing from the back side also?

If these are true then.

Most bang for the buck will be to treat the mid drivers and phase plugs. This is going to be true regardless of the materials these drivers are made of. Also, treating the final edge of the frame will provide you with considerably better vertical dispersion.

Second would be the woofers, more or less depending upon their crossover frequency. If it is below fundamental range, 250 Hz and down, this could wait until you are used to the mid range. If it is in the 250 Hz to 800 Hz range, then these really must be treated along with the mids.

The tweeters can be done last, however, they are going to do as much as the woofers will to describe the performance space, so that aspect will not be correct, unless they are crossed over above 8 kHz or so. At that point treating them will just add beauty to the sound but not have much impact upon space depiction.

I doubt that patterning the boxes will buy you much. Patterning the tweeter carrier could be quite important, to remove it as a diffraction surface for the midrange, and help to blend those frequency bands and normalize time transfer dislocations, caused by surface ringing on the tweeter enclosure.

You could pattern the wood, but why you would want to screw up those lovely surfaces is mostly beyond me. If you have another coat to apply, of whatever finish is needed, on these peripheral box surfaces, you could apply the clear flat Poly S in patterns and it would disappear under the final coat of what ever, but still provide most of the functionality of having it on the surface.

Perhaps you could give all of the rest of us a short discussion, or long, upon cabinet finishing. I have seen this level of finish on some ridiculously expensive cabinets and have always been somewhat jealous. Well, ok, very jealous....

Bud