EnABL - Listening impressions & techniques

Hi Bud and Dave,

Thanks for the great directions - I did everything but practice. The B200s came out good! only a couple block pairs morphed into one, but otherwise it looks great. Those inside rings are TINY! I had to play a lot with printing rings to get just the right sizes, but eventually I got it - for the outer rings, I printed a ring that was just smaller than what I wanted to paint, and then just traced around the outside of it. Actually went quite quickly.

And thanks to Ed for the kit, its perfect!

This weekend, I'm going to measure the modified and unmodified drivers (a friend has a nice Praxis setup). I'll write it up later, but the modified drivers have Dave's phase plugs and were enabl'd according to his recommendations above. I hope to do 0-15-30-45 degree FR and 2-3-4-5 harmonic distortion measurement. Should be fun!
 
I'm just back from taking measurements - and they look good!

Here is a B200 with enabl and phase plug, on a circular, 24" baffle, non-centered, measured 15 degrees off axis:
 

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Here is an overlay with a non-modified driver (in green):



Note - we weren't careful about keeping levels the same, which is why the overlay is a little off. Similarly, THD dropped about 6db across the board (from about -54dB to -60dB), which would be great, but we didn't measure at the exact same drive levels, so I'm not totally sure of the results.

I'll post more data/discussion later, when I write up the speakers in another thread...
 

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EnABL FRS8s?

I knocked together a couple of Cyburg's Needles out of chipboard and installed new FRS 8s. I was pleasantly surprised by the sound quality.

I built these to try my hand at EnABLing. I didn't find anything searching "EnABL" + "FRS8".

Is there anything particular to this type of drivers or can I follow the basic instructions?

Advise much appreciated as usual.
 
BudP said:
cuibono,

Thanks for posting your graphs. Probably best to post here until you do testing that has the sort of rigor the technical thread folks want to see.

Bud

I disagree completely. This is precisely what should be on the other thread and not in this one. That thread is where he's going to get the proper scrutiny, rather than passive acceptance that is likely to occur here.

Dave
 
Dave,
Not everybody (including me!) is comfortable with the type of "proper scrutiny" that the other thread seems to be so good at, although it would be good to see the graphs over there.

Cuibono,
Thanks for showing the results of your work and also the way that you have done them - I see you are also getting reasonably good results with the base driver - congratulations.

Bud,
I would like to add my appreciation and thanks for allowing us all to benefit from your years of developing this amazing Enable technique - I think that it can be extended to controlling cone resonance completely, particularly with light cone, high efficiency drivers.
 
PVA

Vinegar will slow down the drying time of PVA. Just add up to 5% to your PVA/water mix. It is also a good solvent for PVA. If you need to remove the glue, or clean it from places where it shouldn't be, vinegar is amazingly fast. For removing PVA, I usually use a mix of 50/50 water/vinegar. I'm not sure how it will affect paper cones if you use it too heavily, but I don't think it will hurt much either.

I will mention again that the AirPen looks like it would be a real help to anyone doing a lot of EnABLing. Haven't tried it yet, but I may, as it could be useful for other things too. It is a pressurized pen with multiple tips for different sized lines and different thicknesses of fluid.

http://www.artisan-es.com/AirPen.htm

http://www.silkpaint.com/airpen/

http://www.baileypottery.com/studioaccessories/airpen.htm
 
oval drivers

Looks like this thread has become inactive, but I'll try asking here anyway.

Are there any general guidelines for doing 6x9 and 4x12 drivers? I have a few pairs of each and thought it would be fun to give them a try EnABLed, but I'm not quite sure how to work it. Would the lines and spacing still be the same as if they were round drivers? I asked before on the original thread, but things were going hot and heavy on testing and I think no one even noticed the question. I'm not asking for any heavy lifting, like templates, patterns, and such, just a generic guide - that is, do these vary from the guidelines for the round ones, and if so, how?

TIA
 
berm,

I have treated a dozen or so oval speakers. Tried using a fixed angular division and then a fixed length of block set, based upon the overall distance around the oval. The second is pretty difficult to do with ease, unless you have a vector based drawing program and can make guide templates that either drop into the cone, just below where the pattern is to be placed or sitting up on the surround.

The fixed length seemed to sound better overall, but it was not a big difference.

I have not tried the mid cone ring here, from Soongsc's investigations, but I am quite certain it would be worth doing.

I am planning to treat a series of ovals, with whizzer cones, this summer and I do intend to experiment with a number of schemes.

So, if you have Corel Draw or Illustrator, you can take one of the basic patterns and distort it's perimeter to get essentially the same size blocks everywhere, or, use a polar coordinate graph paper to obtain blocks sized to the circumference being swept by the 10 degree arcs. Either appears to work. If you want the vector based patterns, just PM me with an email address and I will send you what I use.

Bud
 
Bud,

Thanks for the reply. I really appreciate all the effort you've put into this since your first responses on the Walsh clone thread - and the patience you've shown with those who have good challenges but sometimes lack tact in the way they express them.

I won't be doing this immedaltely, as I am moving in the meantime and won't have the time, so I will wait and see what pops up later before trying mine (unless I get some play time and try it on a couple of oval drivers - they're not expensive ones, so no big deal).

Thanks, and keep up the great work.
 
Um - not to restir a hornet's nest, but...

...having now done a (single) blind comparison of EnABL/non-EnABL drivers, it would be intellectually dishonest to not report the results.

The setup, at this years Vancouver Island diyFEST, was this: two identical pairs of stand-mount single-driver full-range speakers set up in Dave's living room, with each channel (L & R) having an EnABLed and non-EnABLed driver side-by-side. Each channel's pair was covered by a towel, so that one couldn't see which speaker was moving (or indeed which - the inner or outer of the two - was EnABLed). An A/B switch was positioned by the listening chair. I had no idea which switch position was which. Also, I took care to do the test when no-one else was in the room, so I wasn't picking up subtle cues from anyone who did know.

I was not expecting to hear a difference, and my ears are far from golden. So I'm somewhat surprised to report that there was a difference, and it was not subtle. It was also not easy to characterize, and I can't do so in terms of frequency response, and I'm not very fluent in audiophile-speak (besides, I can never tell when the blacks get blacker). All I can say is that the music was somehow more alive, the sound richer, and there was a greater sense of the musicians being present.

Possible conclusions:

1) The test was a cheat, and the speakers being compared differed in other ways. This could be true, since I didn't look later to confirm that the speaker pairs were in fact the same. I didn't bother because I know the people involved and trust their integrity, so for me this is only logically possible, not contingently so. But that may or may not be true for you.

2) I was kidding myself, and only imagined I heard a difference. Could be - there's no point in arguing this, since if it was all in my imagination, I'm an unreliable witness whose arguments don't count. ;)

3) There really was a difference, but it was just a difference, not an improvement; or, if it was an improvement, it just happened to work with these drivers. Could be - but it sure sounded like a real improvement to me, and even if it only works on some drivers, in my opinion it's well worth pursuing further.

In retrospect, I wish the switch had been an A/B/X, since even on another occasion when I was out of the sweet spot and others were switching, the change in sound was obvious but could arguably have been cued by the sound of the toggle switch (which was pretty evident). If the setup had been A/B/X (instead of A/B), the ability to identify the EnABLed source then would have provided further evidence for those reading about this. Having listened, though, I myself don't feel I need any further evidence that EnABL is doing something very positive to at least these drivers; and my Fostex 127s are now EnABLed, to my great pleasure.

And (again in retrospect) I just realized as I write this that I missed my chance to say so in person; but thanks, Bud. However it works, it's sure improved my speakers.

Regards.

Aengus
 
Aengus,

I must admit to being a bit amazed by all you have written! Thank you for doing so and you are certainly welcome to any joy these tiny dots of paint can provide.

For those of you wondering why I would say this sort of thing, Aengus and I had a conversation about a pair of 127's in a pair of
Fonken's, with an an EnABL'd front plate, at the recent Vancouver Isle/Planet 10 DIY Audio show, on one of the evenings, likely Friday.
He lead me to believe that he found the processed combo far too polite for his taste in music. They were certainly guilty of that description, one I have heard from a few other folks too.

Now, Aengus brought along a pair of startlingly beautiful Harvey style cabinets, very Retro 50's looking, in their swoopy and very organic shapes. Their Fostex 127 drivers were from the pre EnABL Planet 10 treatment scheme, which I whole heartedly approve of, and the combo was quite nice to listen to, everywhere it played. My assumption was that he had found his sweet spot and would remain there. So, I am surprised to readr his very positive comments, though not at all surprised at his integrity in doing so.

Hats off to you friend, those are just lovely speakers and I am delighted to be able to add to their performance envelope.

Bud
 
Hey Bud! I recently stumbled onto your EnABL process postings. As a patent attorney and a bush-league audiophile, it really intrigued me. I just downloaded you patent and it will accompany me in front of my HiFi gear this evening.

I'm new to this site so I can't email you directly, apparently. Can you send me your Corel file of the pattern please? Does the file allow the pattern to be reduced/enlarged for differnt applications?

Thanks,
Sumadoggie.
 
I am curious to know if anyone has had experience in the EnABL process being applied to vintage Boston Acoustics speakers. I am working on an old pair of A100's. Based on DIY posts I have implemented the following repairs and tweeks..
replaced the foam surounds,
added some sand to the bottom of the box,
replaced internal wiring with cat5 based cables, and
dampened the 10" driver basket
They were beginning to sound pretty good. I have started the EnABL process. First 2 coats of puzzel coat made quite an improvement. I have now put on the enable pattern and the paint is curing. I have yet to find a local supplier of the Microscale gloss coat so that will have to wait a few days. At this stage the puzzel coat caused the sound stage to become 3 dimensional and airy. The drivers seem to have caught up to the tweeters and work well together. At first the EnABL pattern killed the sound while the paint was still tacky. As it hardens, the sound is coming back and it is more refined. I suspect the gloss coat is the next significant step.
I was going to throw these things out, but I have to admit that they are getting pretty respectable.
 
Boston Acoustics

wlowes - I tried to email you but apparently you're not accepting them from this forum. What does the sand do to the sound? Did you put the sand in sealed bags? I have a pair that I recapped with Jantzen Superiors and they improved 100%. I still am missing a stronger midrange. Wondering if the dampening and sand might help. The foams are in good shape.