[jrebman]

Hi Mike,

I'm sure somebody is eventually going to get around to asking this so I might as well be the lightning rod and bring up something that's getting a lot of attention recently... that is treating drivers with the EnABL process.  There, I said it .

At this point I just want to know if you've considered treating, or having a pair of Sapphires treated with the EnABL patterns?

This seems to be one of those not fully understood things, yet seems to be pretty much unanimously regarded as beneficial, if not a paradigm shift.

I've sent a pair of fairly expensive, brand new, and now discontinued drivers to Bud Purvine for EnABLing, and have in my possession a pair of treated drivers that are ready to go into some cabinets, and will be getting their first listen when my new amp arrives.

I realize this kind of thing puts you as a manufacturer in an awkward position, but I do know there are a few other speaker manufacturers who are trying this, and/or have embraced it (at least as an option), and being the trend-setting guy you are, I thought I'd at least put it out for comments and some dialogue.

Hope it doesn't push any buttons,

Jim

P.S. -- I have no business relationship with Bud Purvine, Onetics, Dave Dlugos, or Planet-10 HiFi -- except for the fact, as with ACI, I'm a satisfied customer.

[Mike Dzurko]

Jim:

Definitely no buttons pushed, I think the only bad questions are the ones that aren’t asked. I needed to do a little research into EnABL as I’d heard the word but didn’t know what it referred to.

Every loudspeaker “type” whether planar magnetic, multi-way cone based, single driver, neutron bomb or whatever involves a series of compromises. We each choose the compromises that least get in the way of our enjoyment of music.  From what I could find, it appears that EnABL is a potentially good technique for dealing with some of the inherent compromises of single driver systems. For example, most of these cones are relatively light to gain upper bandwidth. They are generally considerably more resonant than a high quality, dedicated midrange or bass-mid. As mentioned in some of the EnABL writing, part of this is also a matter of terminations between cone-surround and cone-voice coil. It appears that EnABL is really a fairly precise damping technique that will add as little mass as possible. You want to kill what we used to refer to as “cone cry” without losing the high end or cutting sensitivity too much.

The ScanSpeak revelator mid-woofer used in the Sapphire XL is a completely different beast. Because we’re not looking for as much bandwidth and sensitivity, the cone and terminations can be a lot heavier. ScanSpeak did a fantastic job with the cone and the terminations. The “slit cone” technology is just part of it. And it should be great, it is one of the most costly small drivers you can buy.  I firmly believe EnABL or adding any kind of doping or damping to these drivers would only serve to take them towards the dark side.   

[Mike Dzurko]

Jim:

As mentioned in some of the EnABL writing, part of this is also a matter of terminations between cone-surround and cone-voice coil. It appears that EnABL is really a fairly precise damping technique that will add as little mass as possible. You want to kill what we used to refer to as “cone cry” without losing the high end or cutting sensitivity too much.

The ScanSpeak revelator mid-woofer used in the Sapphire XL is a completely different beast. Because we’re not looking for as much bandwidth and sensitivity, the cone and terminations can be a lot heavier. ScanSpeak did a fantastic job with the cone and the terminations. The “slit cone” technology is just part of it. And it should be great, it is one of the most costly small drivers you can buy.  I firmly believe EnABL or adding any kind of doping or damping to these drivers would only serve to take them towards the dark side.   

After going back over what I wrote, I'm adding some edits/clarification.  First, the spacing of the EnABL treatment seems to be critical to success. Again, unless I'm reading something wrong, it looks like the idea is to interfere with standing waves while using the least amount of mass to do so. From what I can see, the spatial relationships look well optimized to this goal.

Second, I should mention that over the years we have done quite a bit of experimentation with various means of addressing these same types of problems in drivers. We've sacrificed many dozens, maybe 100s of drivers to these experiments. Based on this and all the testing we did on the ScanSpeak drivers used in the XLs I'm very sure that adding any treatment would only serve to take away some of the magic that is the result of these extremely well designed and built drivers. 

[satfrat]

Jim:

As mentioned in some of the EnABL writing, part of this is also a matter of terminations between cone-surround and cone-voice coil. It appears that EnABL is really a fairly precise damping technique that will add as little mass as possible. You want to kill what we used to refer to as “cone cry” without losing the high end or cutting sensitivity too much.

The ScanSpeak revelator mid-woofer used in the Sapphire XL is a completely different beast. Because we’re not looking for as much bandwidth and sensitivity, the cone and terminations can be a lot heavier. ScanSpeak did a fantastic job with the cone and the terminations. The “slit cone” technology is just part of it. And it should be great, it is one of the most costly small drivers you can buy.  I firmly believe EnABL or adding any kind of doping or damping to these drivers would only serve to take them towards the dark side.   

After going back over what I wrote, I'm adding some edits/clarification.  First, the spacing of the EnABL treatment seems to be critical to success. Again, unless I'm reading something wrong, it looks like the idea is to interfere with standing waves while using the least amount of mass to do so. From what I can see, the spatial relationships look well optimized to this goal.

Second, I should mention that over the years we have done quite a bit of experimentation with various means of addressing these same types of problems in drivers. We've sacrificed many dozens, maybe 100s of drivers to these experiments. Based on this and all the testing we did on the ScanSpeak drivers used in the XLs I'm very sure that adding any treatment would only serve to take away some of the magic that is the result of these extremely well designed and built drivers. 

That's a very interesting outlook on the Scan Speak that has been EnABL'd. I know very little about all this but from what I've read, I've heard very very little negativity from those to have treated their drivers. I'm seeing nothing but positive opinions from those who have actually tried this process. So I'm a little surprised that you'd shut the door on this Mike w/o even ruining 1 more driver to actually see. Unless this is strictly a business oriented opinion, then it makes perfect sense. I have ScanSpeak 8545 carbon fiber drivers in my Odyssey Lorelei's and I know damn well Klaus would say the same thing about somebody wanting him to support messing with them drivers. BUT if there really is something to all this...something really great,,,, it's only a matter of time before some manufacturer incorporates the EnABL process in their manufacturing. I'm thinking I'll be sitting on the fence for a long time (with my eyes wide open) on this EnABL thingie. 

Cheers,
Robin

[Mike Dzurko]

Robin:

In all the checking I did, I saw nothing except for full-range type drivers. Like I said, for those it could make sense.  The bass-mid in a two-way like the Scan we use is a completely different beast. If I missed something and you know of any info pertaining to drivers other than full-range let me know.

The thing is, we are h-bent on offering the best value product we can. To do this does take sound business decisions on how to spend our resources, specifically R&D. We are constantly evaluating ways to improve our products. In this case, it is far more than just playing with a $400 pair of drivers. It would be the R&D time involved. We take R&D seriously, and to really evaluate something like this would be pretty costly in terms of time. Because it is a technique that from what I can see doesn't seem to offer the chance of improvement to our product, at this point no.  Now, if someone can point me to information that indicates otherwise, I do have an open mind.

[jrebman]

Mike,

Actually, Bud has been doing this for 35 years now and only very recently did his first single driver (Lowther) speaker.  In all those years there was only one driver that didn't show some improvement -- a midrange horn.  He has treated horns, -- both the mouths and diaphragms, all manner of cone drivers from giant sub drivers to mids and tweeters, dome tweeters and midranges.  To the best of my knowledge he hasn't done any ribbon drivers, but I could be wrong about that.  It looks like Al of RAW Acoustics may be getting on board with this, and that's what actually prompted me to see if you had looked into it or had any interest in it, as his speakers are definitely not single, full-range driver types.

I think the pattern has also been applied to baffles and BR ports as well.

The comment that most people make after hearing this is that they can't go back to "normal" speakers as they just don't sound right anymore, and I'm assuming that most people are talking about speakers they already know and love.

Anyway, that's what I know at the moment.

-- Jim

[satfrat]

Robin:

In all the checking I did, I saw nothing except for full-range type drivers. Like I said, for those it could make sense.  The bass-mid in a two-way like the Scan we use is a completely different beast. If I missed something and you know of any info pertaining to drivers other than full-range let me know.

The thing is, we are h-bent on offering the best value product we can. To do this does take sound business decisions on how to spend our resources, specifically R&D. We are constantly evaluating ways to improve our products. In this case, it is far more than just playing with a $400 pair of drivers. It would be the R&D time involved. We take R&D seriously, and to really evaluate something like this would be pretty costly in terms of time. Because it is a technique that from what I can see doesn't seem to offer the chance of improvement to our product, at this point no.  Now, if someone can point me to information that indicates otherwise, I do have an open mind.

Sorry Mike,,, I'm just a dumba$$ consumer cruising the web in search of info that'll take what I now have in audio to the next level. I'm in no position to tell anyone anything other than uneducated opinions that come from my trusting my ears. I'm sure as hell not in a position to tell you anything from a R&D. If anything I need to sit for a long time on this EnABL fence until such time that business's like your own can actually verify this process. If you say it's not worth looking at, then that carries weight in of itself. Maybe IF at some point that another reputable business has something of a positive note to say about EnABL, you'll need to reconsider. As it stands now Mike, looks like we'll both be sitting on this EnABL fence.  aa
Hope you didn't see any negativity in my post Mike, I was just surprised after all the positive things that I've read about EnABL'd drivers that you would dismiss it so abruptly. Looks like I'll put a cushion on that fence,,,, 

Happy Holidays,
Robin

[Mike Dzurko]

Mike,

Actually, Bud has been doing this for 35 years now and only very recently did his first single driver (Lowther) speaker.  In all those years there was only one driver that didn't show some improvement -- a midrange horn.  He has treated horns, -- both the mouths and diaphragms, all manner of cone drivers from giant sub drivers to mids and tweeters, dome tweeters and midranges.  To the best of my knowledge he hasn't done any ribbon drivers, but I could be wrong about that.  It looks like Al of RAW Acoustics may be getting on board with this, and that's what actually prompted me to see if you had looked into it or had any interest in it, as his speakers are definitely not single, full-range driver types.

I think the pattern has also been applied to baffles and BR ports as well.

The comment that most people make after hearing this is that they can't go back to "normal" speakers as they just don't sound right anymore, and I'm assuming that most people are talking about speakers they already know and love.

Anyway, that's what I know at the moment.

-- Jim

I read through most of what I could find including the 1994 patent. At this point my gut and 30+ years experience tell me the following:

- The process will definitely change the sound of drivers. In many cases, especially many of the relatively light coned full-range drivers, this could be a significant improvement
- I am an extremely open-minded individual, but I also possess a sense of healthy skepticism. If I didn't, I would have gone out of business a long time ago. This treatment obviously will change the sound of the driver, I just got completely turned off by some of the claims being made.
- I didn't find any A-B tests (might have missed them).  I'm talking about some direct comparisons of treated and untreated drivers. And here's the thing. These tests will be difficult because most people will assume the treated drivers sound better, but they might just sound different.
- The sliced cones of the ScanSpeak Revelators likely accomplish a similar effect. These drivers are a large part of the reason why the Sapphire XL is such an exceptional loudspeaker.  My point here is that the right amount of anything is "just right" and adding more will probably not be an improvement. 

 I would like to try this out for my own curiosity. Heck, if it does 1/4 of what is claimed, we could save a small fortune by purchasing less expensive drivers and having them modified. My only problem is TIME. I just don't have a spare week or so right now, don't have a spare 10 minutes actually   Please DO send links, etc. that I can follow as time permits. Jim, I do want to thank you for bringing this up, I had heard the word but nothing else, and I do find it very interesting!

[Mike Dzurko]

Robin:

In all the checking I did, I saw nothing except for full-range type drivers. Like I said, for those it could make sense.  The bass-mid in a two-way like the Scan we use is a completely different beast. If I missed something and you know of any info pertaining to drivers other than full-range let me know.

The thing is, we are h-bent on offering the best value product we can. To do this does take sound business decisions on how to spend our resources, specifically R&D. We are constantly evaluating ways to improve our products. In this case, it is far more than just playing with a $400 pair of drivers. It would be the R&D time involved. We take R&D seriously, and to really evaluate something like this would be pretty costly in terms of time. Because it is a technique that from what I can see doesn't seem to offer the chance of improvement to our product, at this point no.  Now, if someone can point me to information that indicates otherwise, I do have an open mind.

Sorry Mike,,, I'm just a dumba$$ consumer cruising the web in search of info that'll take what I now have in audio to the next level. I'm in no position to tell anyone anything other than uneducated opinions that come from my trusting my ears. I'm sure as hell not in a position to tell you anything from a R&D. If anything I need to sit for a long time on this EnABL fence until such time that business's like your own can actually verify this process. If you say it's not worth looking at, then that carries weight in of itself. Maybe IF at some point that another reputable business has something of a positive note to say about EnABL, you'll need to reconsider. As it stands now Mike, looks like we'll both be sitting on this EnABL fence.  aa
Hope you didn't see any negativity in my post Mike, I was just surprised after all the positive things that I've read about EnABL'd drivers that you would dismiss it so abruptly. Looks like I'll put a cushion on that fence,,,, 

Happy Holidays,
Robin

Robin:

I do apologize if it seemed that I was dismissing "abruptly" .  I'm not really dismissing, just explaining that to really investigate this is definitely going to take some time. On the road this morning I was thinking of setting up a listening comparison between a pair of modified speakers vs. unmodified. We could hold this test in our new, ALMOST completed listening room sometime later this winter or spring.  Just a thought, Happy Holidays to you too!

[BudP]

Hi Mike,

Jim called me today to check on his unobtanium drivers, which I won't start an engineering process on until this weekend. He dropped the name of this site so I would come for a look.

I think I should make a few unsolicited comments.

Full Range speakers had not been my interest until a friend in Detroit sent me his DX 4 Lowther's and pretty much demanded I treat them. My personal reference system is composed of a Dynavox 9" woofer, Vifa 3" dome, two Radio Shack Linnaeum tweeters and a Pioneer piezo film tweeter. All are EnABL'd and to my surprise are coherent and quite musical. They will also exceed 107 dB with ease, though, the resistance ports are showing distress at this level. I had concocted it out of boredom and a desire to use as disparate a set of drivers as I could find, just to see how the process held up. That was 7 years ago.

The real meat of the process is the elimination of same frequency, termination induced, transient ringing, in the boundary layer of any type of driver. The removal of this information, by properly terminating an emitter surface, provides a couple of benefits.

The things it does not do are, alter the harmonic content of a driver to any measurable extent, alter the frequency response to any measurable extent, add enough mass to alter the FS, or really any Thiele/Small characteristic and until recently, disperse the major nodal energy storage mechanism for a driver. These comments are true for light cones, heavy cones, domes, planar and dome tweeters and horns and their compression drivers. In short, none of the pistonic based test suite values are altered.

Hence, the drivers don't sound different. Their character remains intact.

What changes are things that are not "heard" anymore. Within an orchestral passage, with every instrument marking it's sonic territory, there is no longer a blending of similar frequency response signals, the entry and exit character of transients contain all of the discreet time train cues, in their correct placement, across multiple drivers. Delicate, wide band, low level information, maintains it's coherence and is easily retrievable, but without any requirement to pay attention to it. Shrieks and pinched sounds do not arise, ever.

The test suite changes we have found applicable have shown a change in high frequency phase position, above 1K, on a Jordan metal driver, from -15 degrees to + 15 degrees, without an alteration in frequency response. The nominal treatment you have seen, places the high frequencies at a normalized phase, with respect to the 1K phase reference. A second is the dramatic shortening of ringing on the driver, as seen in CSD plots. A third, and very recent discovery, is the complete dispersion of a strong nodal ringing, found in Jordan drivers and all others in my experience.

The "listening tests" should come from those without my obvious bias, so here are a few, though all are from single driver systems.
http://www.diyaudio.com/forums/showthread.php?s=80a15a3a7aafb1586e01763c9687254d&threadid=111830
http://www.diyaudio.com/forums/showthread.php?postid=1354867#post1354867
http://www.diyaudio.com/forums/showthread.php?postid=1377025#post1377025
And from the Hawthorne site, page 10, 2nd post down, by Tea Head.
http://www.hawthorneaudio.com/forum/viewtopic.php?t=1429&postdays=0&postorder=asc&start=120

A consequence of treating your SEAS driver will be a need to also treat the dome tweeter. A consequence of treating the tweeter will be normalized phase, which may cause an alteration in your crossover, or may not. Both will benefit from having their surfaces turned into a single pass transmission line. How much benefit? Typically 50 to 60 dB down in absolutely clear and coherent information. Typically 9 dB or so greater dynamic headroom, without suffering the usual compressions and shredding of coherence.

The dangers? Loss of those cues that the system is being played too loudly for it's own safety and the longevity of your good relationship with neighbors.

Should you offer this process? Maybe not. It is a time intensive procedure, about an hour for a driver in total mfg time.

The paradigm shift that Dave Dlugos comments on is true. It is also true that most folks are unwilling to go back to untreated drivers, with about 15 minutes of exposure. Blind tests are quickly negated in value, because the differences become so noticeable, upon a few switches, that the tests become useless for attempting to confuse a listener about what they are, or are not hearing. But, this is not a change in sound character, just quantity of information, of all sorts, and a release from a distress you had no idea you were operating under. What is left is just the music, the concept of "speakers" and "audio" quickly evaporates.

Bud

[richidoo]

Coool!!    I think I am slipping, slipping slipping into maybe trying this......... Nice write up Bud - Thanks! 
Rich

[griller]

Wow