Bi-Amplification

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David Ellis

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« Reply #40 on: 12 Apr 2005, 11:31 pm »
Doug,

Quote
again, i am not sure what useful info can be inferred here, re: active vs passive.


How familair are you with the sound quality & character of the drivers used in these speakers?  Exactly how "different" do you think they sound?  Further, which drivers do you think sound better?

Do you think John K's speaker objectively or subjectively "failed" in any facet of active crossover implementation?  If so, please explain?  

Given the objective cost of parts implemented in these speakers, which speaker should sound better?

Is there a better a/b example of passive and active crossover comparison using arguably the best drivers, crossover components, and design skill available?

Dave

EProvenzano

Bi-Amplification
« Reply #41 on: 13 Apr 2005, 03:16 am »
Quote from: doug s.
i am not sure how much useful info can be garnered from this. did you disconnect the passive x-over prior to going active? were you prewiously passively bi-amping w/these same amps? it's not always easy (or ideal) to use s/s amplification *and* tubed amplification when the x-over point is much higher than ~300hz... active *or* passive...

thanks... .


Sorry for the confusion. I thought it was obvious, I was bypassing the passive xo.

I still stand by my comments. In the hands of a novice with limited measurment tools, I doubt that an active approach will give better results than a well implemented passive design, in my experience.

Best regards,
EP

EProvenzano

Bi-Amplification
« Reply #42 on: 13 Apr 2005, 03:27 am »
Quote from: doug s.
it's not always easy (or ideal) to use s/s amplification *and* tubed amplification when the x-over point is much higher than ~300hz... active *or* passive... .


While we're on the subject of 'useful information', could you tell me why you think a combination of Solid State and Tubes is not ideal beyond a 300hz cross-over point?

I appologize for my tone, but your initial question to me seems less than polite, and since you don't have a clue what kind of person I am, I took some offense to it.

Thanks.

doug s.

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« Reply #43 on: 13 Apr 2005, 12:30 pm »
Quote from: David Ellis
Doug,

How familair are you with the sound quality & character of the drivers used in these speakers?  Exactly how "different" do you think they sound?  Further, which drivers do you think sound better?

Do you think John K's speaker objectively or subjectively "failed" in any facet of active crossover implementation?  If so, please explain?  

Given the objective cost of parts implemented in these speakers, which speaker should sound better?

Is there a better a/b example of passive and active cros ...

hi david, the only point i am trying to make is that one should be "comparing apples to apples".  take a speaker that's active, & then try to make it passive.  take a speaker that's passive, & then try to make it active.  

comparing two completely different speakers, designed with two completely crossover philosophies - one active, the other passive - & then saying they were both excellent does not convince me that active x-overs crossovers are therefore not better than passive x-overs. too many other wariables in the equation.

regards,

doug s.

David Ellis

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« Reply #44 on: 13 Apr 2005, 12:52 pm »
So,

Are you able to specifically answer any of my questions?

Dave

doug s.

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« Reply #45 on: 13 Apr 2005, 01:06 pm »
Quote from: EProvenzano
Quote from: doug s.
it's not always easy (or ideal) to use s/s amplification *and* tubed amplification when the x-over point is much higher than ~300hz... active *or* passive... .


While we're on the subject of 'useful information', could you tell me why you think a combination of Solid State and Tubes is not ideal beyond a 300hz cross-over point?

I appologize for my tone, but your initial question to me seems less than polite, and since you don't have a clue what kind of person I am, I took some offense to it.

Thanks.

hi e,

i am sorry if my initial tone seemed less than polite - no offense was meant.  and, for further clarification, i am assuming that, prior to going active & bypassing the passives of the 1801, you were bi-amping w/the same amps?

re: bi-amping w/tubes & solid state at higher x-over points, tho i am not an electrical engineer, i have heard from many different folks that this is difficult to do because of the different electrical response chartacteristics of tube vs s/s amps.  something having to do w/the speed of s/s amps, & their typically much greater damping factor.  which is why this is supposedly hard to do once you get out of the low bass range.

personally, i have never tried tube/solid state combinations w/anything other than subwoofer/monitor interface & active x-over, and the highest x-over point i ever used was 125hz.

again, i wasn't trying to be rude, i was yust looking for further clarifications.  i find the discussion between active vs passive x-overs for speakers to be fascinating, and one that i am particularly interested in, as i consider "rollng my own" speakers some time...

regards,

doug s.

doug s.

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« Reply #46 on: 13 Apr 2005, 02:08 pm »
hi dave,

ok, here goes  :)

Quote from: David Ellis
Doug,

How familair are you with the sound quality & character of the drivers used in these speakers?  

i am not wery familiar w/the excel drivers, tho i have heard other seas drivers that i find to be really nice.  in fact my present speakers have seas midwoofers.

i have heard the tweeter used in the veracity speaker & was not at all impressed, tho i suspect crossover implementation may have had something to do w/it...  :wink:

Quote from: David Ellis
Exactly how "different" do you think they sound?  Further, which drivers do you think sound better?

re: how "different" they sound, for the two speakers you mention, i have not heard eather, so i cannot comment.  but i think, in general, open-baffle speakers do have a different soundstaging characteristic than forward-firing speakers.

re: which drivers sound "better", well i wouldn't say *better* necessarily, but i like drivers from many mfr's, including scan speak, dynaudio, eton, hi-vi research, focal...

Quote from: David Ellis
Do you think John K's speaker objectively or subjectively "failed" in any facet of active crossover implementation?  If so, please explain?

absolutely not.  how am i in any position to make a judgment about this?

Quote from: David Ellis
Given the objective cost of parts implemented in these speakers, which speaker should sound better?

i am not sure the cost of parts is relevant here.  (or in lotsa audio gear, for that matter.)

Quote from: David Ellis
Is there a better a/b example of passive and active crossover comparison using arguably the best drivers, crossover components, and design skill available?

absolutely - it should be the same loudspeaker set up both active & passive.  

i remember several years back, i attended a s'phile show in nyc.  my two personal top sounds of the show were one room w/diapason adamantes ll's, being driven by n.e.w. electronics, and jadis eurythmie horns driven by jadis electronics.  does this mean these sounded the same?  that, therefore, two way monitors sound like horns?  :o

personally, i would like to hear about the veracity ht3 set up w/active x-overs, compared to the "stock" ht3.  using something like the deqx might be good...

regards,

doug s.

David Ellis

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« Reply #47 on: 13 Apr 2005, 05:04 pm »
It appears you only have personal exposure to 1 of the drivers used in these speakers - the ribbon tweeter.  Is that correct?

I asked you if you have every experienced a better a/b comparison between active and passive crossovers.  Well, have you?

Quote
... and jadis eurythmie horns driven by jadis electronics. does this mean these sounded the same? that, therefore, two way monitors sound like horns?


I really don't have a objective or experiential knowledge about any of this gear, and would therefore not make any assertions about how this could/should sound.

Quote
but i think, in general, open-baffle speakers do have a different soundstaging characteristic than forward-firing speakers.


.... How do you think they sound different?  Further do you think open baffle speakers sound subjectively "better" than box speakers?  

Also, objectively, how could the Veracity 3-way be a better sounding speaker?  And, how could the NAO objectively be a "better" speaker?  Could there possibly be any combination of drivers, parts and implementation that could yield better sound quality?

Quote
absolutely not. how am i in any position to make a judgment about this?


Personal knowledge & experience.

Quote
i am not sure the cost of parts is relevant here. (or in lotsa audio gear, for that matter.


Do you think that among a single product line that cost generally equates to quality?

Do you think both Dennis Murphy (Veracity 3 designer) and John K did the very best possible design work with the drivers used in their speakers?

doug s.

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« Reply #48 on: 13 Apr 2005, 05:34 pm »
Quote from: David Ellis
It appears you only have personal exposure to 1 of the drivers used in these speakers - the ribbon tweeter. Is that correct?

basically yes.  i have heard the excel drivers, but only in passing, not enuff to make any worthwhile opinions on how they sound.

Quote from: David Ellis
I asked you if you have every experienced a better a/b comparison between active and passive crossovers. Well, have you?

no you didn't.  you asked if there is a better a/b example.  period.  whether or not i have experienced it is a different question altogether.  i have experienced *no* a/b examples - better, worse, or the one you mention.  but it doesn't mean there isn't a better one.  and the example(s) i presented is(are) better, imo.

Quote from: David Ellis
Quote:
... and jadis eurythmie horns driven by jadis electronics. does this mean these sounded the same? that, therefore, two way monitors sound like horns?


I really don't have a objective or experiential knowledge about any of this gear, and would therefore not make any assertions about how this could/should sound.

not what i was getting at.  i was only getting at the fact that it's more difficult to compare different things.  it's easier if known and easily eliminated wariables are in fact eliminated, imo.

Quote from: David Ellis
Quote:
but i think, in general, open-baffle speakers do have a different soundstaging characteristic than forward-firing speakers.


.... How do you think they sound different? Further do you think open baffle speakers sound subjectively "better" than box speakers?

i think open baffle speakers have a tendency to exaggerate the soundstage.  personally, i prefer non-open-baffle speakers.

Quote from: David Ellis
Also, objectively, how could the Veracity 3-way be a better sounding speaker? And, how could the NAO objectively be a "better" speaker? Could there possibly be any combination of drivers, parts and implementation that could yield better sound quality?

i think the nao could be made to sound better if it were fully active.  same goes for the veracity ht3.  of course, this is yust my opinion, & i don't state it to be anything different.  

all i have been saying here is that comparing the nao as it now exists, to the ht3 as it now exists, sheds little if any light on whether or not my opinion is correct that making these speakers (or *any* passive x-over speakers) fully active will make them better.

Quote from: David Ellis
Quote:
absolutely not. how am i in any position to make a judgment about this?


Personal knowledge & experience.

thank you for stating the obvious.  i have never inferred anything different.

Quote from: David Ellis
Quote:
i am not sure the cost of parts is relevant here. (or in lotsa audio gear, for that matter.


Do you think that among a single product line that cost generally equates to quality?

generally yes, but only generally.  i think there's too many exceptions & other wariables to accept this as a hard fast rule.  sometimes less is more.

Quote from: David Ellis
Do you think both Dennis Murphy (Veracity 3 designer) and John K did the very best possible design work with the drivers used in their speakers?

i think *they* think they did.  for what *i* think, see my prior comments.

regards,

doug s.

David Ellis

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« Reply #49 on: 14 Apr 2005, 02:38 am »
So,

Basically the only thing you believe is that dipoles sound different than box speakers and believe box speakers are generally better?  Or, do you believe box speakers and dipoles are "different" but "equal"?

Is there something else that invalidates this a/b test from your perspective?

doug s.

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« Reply #50 on: 14 Apr 2005, 02:13 pm »
Quote from: David Ellis
So,

Basically the only thing you believe is that dipoles sound different than box speakers and believe box speakers are generally better?  Or, do you believe box speakers and dipoles are "different" but "equal"?

Is there something else that invalidates this a/b test from your perspective?


jeez, how many times do i have to say it?  there is ONE thing (in my perspective, of course), that inwalidates the a/b test you reference.  the speakers compared need to be IDENTICAL.  they are not.  even if they were both dipoles, or both conwentional box-type speakers, if they are not the SAME speaker, then it's not a walid a/b comparison.  imo, of course.

at least eprovenzano's a/b uses the same speakers, & from what i can determine, also seems to have used the same amplification.  that's a more walid test, imo.

doug s.

doug s

JoshK

Bi-Amplification
« Reply #51 on: 14 Apr 2005, 03:11 pm »
Quote from: doug s.
i think open baffle speakers have a tendency to exaggerate the soundstage.


How so?  In which dimension, width, depth, etc?  Which dipoles have you heard?  

I have little if no experience with dipoles, I have been meaning to go hear a pair when/if I get the chance, and IMHO planars such as Magneplanars aren't a good example of dipoles when comparing to dynamic box speakers because there is a whole slew of other variables introduced.  I still really want to hear a dynamic dipole because the theory should would suggest that they would minimize distortion of the soundstage thereby allowing the soundstage to be reproduced more accurately than an analogous box speaker.

doug s.

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« Reply #52 on: 14 Apr 2005, 05:40 pm »
Quote from: JoshK
How so?  In which dimension, width, depth, etc?  Which dipoles have you heard?  

I have little if no experience with dipoles, I have been meaning to go hear a pair when/if I get the chance, and IMHO planars such as Magneplanars aren't a good example of dipoles when comparing to dynamic box speakers because there is a whole slew of other variables introduced.  I still really want to hear a dynamic dipole because the theory should would suggest that they would minimize distortion of the soundstage thereby allowing the soundstage to be reproduced more accurately than an analogous box speaker.

hi josh,

i, too, haven't any experience w/dipoles that are made w/dynamic drivers.  i, too, would like to hear speakers like this.  yure right - supposedly this type of soundstage will be reproduced more accurately.  typical planar/ribbon type dipoles i have heard, have soundstaging that sounds way too big - width mostly,  also depth - way too difuse for me.  magnaplaner is a perfect example.  i have heard others, but names escape me.  martin logan is one that isn't as bad (due to its curved shape?), but i don't like these, for other reasons - mainly bad interface between the active driver & the panel.  i like the cls' (no active driver), but it's not dynamic enuff...

doug s.

David Ellis

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« Reply #53 on: 14 Apr 2005, 06:50 pm »
Quote
hi josh,

i, too, haven't any experience w/dipoles that are made w/dynamic drivers. i, too, would like to hear speakers like this


Then, how could you make the statement?

Quote
i think open baffle speakers have a tendency to exaggerate the soundstage. personally, i prefer non-open-baffle speakers.


What is your basis for this?

doug s.

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« Reply #54 on: 14 Apr 2005, 07:30 pm »
Quote from: David Ellis
Quote
hi josh,

i, too, haven't any experience w/dipoles that are made w/dynamic drivers. i, too, would like to hear speakers like this


Then, how could you make the statement?

what statement?

Quote from: David Ellis
Quote
i think open baffle speakers have a tendency to exaggerate the soundstage. personally, i prefer non-open-baffle speakers.


What is your basis for this?

listening to open baffle speakers that aren't of the dynamic driver type.  

dave, it's obvious you have some sorta grudge here, not sure what it is or why.  info for EVERY question you have asked of me has prewiously been stated.  while i am not sure which statement yure referring to when you say: "Then, how could you make the statement?", i betcha anything that when ya clarify for me, my answer will have awreddy been stated in this thread.  similar to the fact that i have awreddy stated which type of open baffle speakers i have heard that i feel exaggerate the soundstaging.

doug s.

David Ellis

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« Reply #55 on: 14 Apr 2005, 07:43 pm »
Doug,

I don't have a grudge.  I am simply trying to obtain the basis for your statements of knowledge. I want to be very clear about this before I summarize.

Again,

You wrote, "i think open baffle speakers have a tendency to exaggerate the soundstage. personally, i prefer non-open-baffle speakers. "  

The topic of disccusion was John K's dynamic driver bipole.  Did you fail to mention that you were addressing yet another kind of speaker - Magneplanar?

Later you wrote, "i, too, haven't any experience w/dipoles that are made w/dynamic drivers. i, too, would like to hear speakers like this"

Dave

doug s.

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« Reply #56 on: 14 Apr 2005, 07:56 pm »
Quote from: David Ellis
Doug,

I don't have a grudge. I am simply trying to obtain the basis for your statements of knowledge. I want to be very clear about this before I summarize.

Again,

You wrote, "i think open baffle speakers have a tendency to exaggerate the soundstage. personally, i prefer non-open-baffle speakers. "

The topic of disccusion was John K's dynamic driver bipole. Did you fail to mention that you were addressing yet another kind of speaker - Magneplanar?

Later you wrote, "i, too, haven't any experience w/dipoles that are made w/dynamic drivers. i, too, would like to hear speakers like this"

Dave

ok dave.  yure right about one thing. initially, i dint specifically clarify my statement re: which types of dipole speakers i have or have not heard.   i dint think it relevant to the only point i have been trying to make in this thread, which is that to do a meaninful a/b comparo between active & passive x-overs, the same speaker needs to be tested in both configurations.

but, by the time you had asked me your last questions, i *had* made clear what types of dipole speakers i have heard.  so, ya, i figured ya had a grudge, since the basis for my statements were awreddy known, w/o ya having to ask.

doug s., anxiously awaiting your summary...

David Ellis

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« Reply #57 on: 14 Apr 2005, 08:27 pm »
Summary,

In my opinion there are 2 variables looming today in hifi that "appear" to be superior if implemented correctly.

1.  Dipoles

2.  Active crossovers

I believe the a/b test between John K's NAO and Jim Salks Veracity places the traditional passive crossover box loudspeaker on an equal plane.  Actually Jim's loudspeaker received marginally higher overall marks from the @25 guys in the room.  I believe this a/b test fairly successfully addresses both of these 2 variables.

I believe both of these speaker are debatably the very best speakers on the planet.  You can spend more, but you won't get "more" than what's available in these speakers.  I believe Dennis Murphy and John K gave these projects their maximum effort, and the quality of their work on these projects is on par with Sigfreid Linkwitz and... well... anybody.

I believe dipoles can be very good speakers.  Active crossover can produce a very good crossover.  Consdiering the latter, IMO, the common hifi amplifier fails to take full advantage of the active crossover.  There may be more on this in a couple years from Dave Ellis.  However, as things currently rest, a good passive crossover box speaker is certainly on-par with the active crossover dipole speaker.

Your assertion that this test was comparing "apples to oranges" seems questionable.

1.  You have no exposure or experience with dipoles

2.  You don't have knowledge or ability to evaluate John K's active crossover implementation.

3.  You have no experience with any of the drivers used in either of these two speakers - except the ribbon tweeter.

4.  You were NOT present to hear these speakers.

5.  You have no experience or exposure to conventional dipole speakers.

In short, I totally disagree with your assertion that this test is was "comparing apples to oranges".  IMO, you haven't the knowledge, experience, or exposure to reify this statement.  In this case, you can't identify what is an "apple" or what is an "orange".  

I do agree that a better scientific test would isolate 1 variable ( i.e.  active crossover ), and control for all others.  However, this test remains very valid and is a very signficant data point for anyone who might assert the clear superiority of the active crossover or the dipole speaker.  

Also, FYI, Ed West in Seattle performed this 1 variable test using the SPCA loudspeaker.  The SPCA is not a top notch speaker, but has $1k sonics in a smallish cabinet.  It sounds very respectable.  He compared a passive crossover and active crossover with perfectly identical slope.  The result... nobody had a preference.

doug s.

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« Reply #58 on: 14 Apr 2005, 09:14 pm »
Quote from: David Ellis
Summary,

In my opinion there are 2 variables looming today in hifi that "appear" to be superior if implemented correctly.

1.  Dipoles

2.  Active crossovers


I believe the a/b test between John K's NAO and Jim Salks Veracity places the traditional passive crossover box loudspeaker on an equal plane.  Actually Jim's loudspeaker received marginally higher overall marks from the @25 guys in the room.  I believe this a/b test fairly successfully addresses both of these 2 variables.


yer a/b test is certainly relevant to item one, where by definition, yure comparing two different driver implementations.

completely irrelevant to item #2, imo.  the loudspeakers are completely different, w/completely different design philosophies, & by definition, active vs passive crossover design as the wariable, is for the same loudspeaker - which is better.

Quote from: David Ellis
I believe both of these speaker are debatably the very best speakers on the planet. You can spend more, but you won't get "more" than what's available in these speakers. I believe Dennis Murphy and John K gave these projects their maximum effort, and the quality of their work on these projects is on par with Sigfreid Linkwitz and... well... anybody.

I believe dipoles can be very good speakers. Active crossover can produce a very good crossover. Consdiering the latter, IMO, the common hifi amplifier fails to take full advantage of the active crossover. There may be more on this in a couple years from Dave Ellis. However, as things currently rest, a good passive crossover box speaker is certainly on-par with the active crossover dipole speaker.

could wery well be true...  talking about the best speakers in the world, or dipole vs box speaker wasn't something i was considering here...

Quote from: David Ellis
Your assertion that this test was comparing "apples to oranges" seems questionable.

1. You have no exposure or experience with dipoles

2. You don't have knowledge or ability to evaluate John K's active crossover implementation.

3. You have no experience with any of the drivers used in either of these two speakers - except the ribbon tweeter.

4. You were NOT present to hear these speakers.

5. You have no experience or exposure to conventional dipole speakers.

In short, I totally disagree with your assertion that this test is was "comparing apples to oranges". IMO, you haven't the knowledge, experience, or exposure to reify this statement. In this case, you can't identify what is an "apple" or what is an "orange".



i can't identify what is an "apple" or what is an "orange"?!?  :o  yure kidding, right???

the fact is that, for trying to determine whether or not an active x-over is better than a passive x-over, using the nao & the ht3 makes the experiment 100% totally flawed on its face, from the outset.  not one statement above, re: my experience, whether or not i've heard these speakers, etc., contradicts this fact.  

an apples-to-apples comparo would be using two pairs of either of the above loudspeakers - one optimized w/active x-over, the other w/passive.  but, this is so simple, & such basic scientific testing procedure, i cannot really believe that i am arguing this w/someone.  :roll:

Quote from: David Ellis
I do agree that a better scientific test would isolate 1 variable ( i.e. active crossover ), and control for all others. However, this test remains very valid and is a very signficant data point for anyone who might assert the clear superiority of the active crossover or the dipole speaker.

for dipole vs forward-firing, by its wery nature, it's apples-to-oranges, so i have no issues here.  i guess i could get really technical, & say that to truly do it correctly, ya would need something like, say a pair of ht-3's vs a pair w/a second pair outta phase directly behind them.  but, this opens up a whole other can of worms.

but, for the active vs passive x-over, it's a total no-brainer to isolate the other wariables.  at the wery least, ya should be comparing two speakers of the same type - this doesn't even do that - one's a dipole, the other is forward-facing.  *completely* flawed for testing different x-over types, imo.  and, my experience or lack thereof, w/these particular speakers doesn't change this fact one iota.


Quote from: David Ellis
Also, FYI, Ed West in Seattle performed this 1 variable test using the SPCA loudspeaker. The SPCA is not a top notch speaker, but has $1k sonics in a smallish cabinet. It sounds very respectable. He compared a passive crossover and active crossover with perfectly identical slope. The result... nobody had a preference.

this is a relevant data point, for sure.  not so for the dipole quasi-active vs the forward-firing passive, tho.  i don't need experience w/any of these speakers to be able to figure this out.  it's poor science, plain & simple.

regards,

doug s.

JoshK

Bi-Amplification
« Reply #59 on: 14 Apr 2005, 09:36 pm »
If you look back on page 2 of this thread you will see that I objected to the testing method as well.  Also to Dave calling the NAO an active amping speaker, which is only partially true.  

But from what I gather Dave is trying to say, no matter what scientifically better methods of implementation used the end result were that the NAO and the HT3 were still about par, no obvious break-through in end result.  This is a significant point.  This is like the difference in my field between statistical and economic significance.  

Like I said previously, I don't have any strong opinions on the matter. Like Dave I am persuaded by the theory to think it *should* be better, or atleast makes some sense that it could but in the end if it is terribly more difficult and expensive to do and doesn't afford a likewise step up in performance then all the theory in the world is moot.  

I personally don't like the test method or all the inferences made from it but the end result is the end result.  If the guys thought the two were neck in neck then nothing else really matters.   I just think the NAO is probably not the greatest example of what can be done with dipoles or active amping.  John K is obviously a smart cookie, but equally knowledgeable designers out there have challenged him on a few key points (implicitly or explicitly) that I would also think would allow room to take it a couple steps further.  We shall see....