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post #91 of 168 Old 07-02-2011, 08:56 PM
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AJ, please shoot an email to Meridian and Harman and let them know that what they have been doing for decades doesn't include science and research. I'm sure they will appreciate the heads up.

Cheers

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post #92 of 168 Old 07-02-2011, 09:25 PM
 
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Quote:
Originally Posted by Bigus View Post

Diomania, I was looking at the graph aj posted, the ONLY graph he posted of that speaker. I usually browse and post from my phone. Chasing down links in a full web browser and returning to the forum isn't a trivial exercise. I know now that anything aj posts is subject to gross misrepresentation so I won't make that mistake again. But in that context, when I made that original comment there were but three response curves to compare, unlabeled, but appearing as if we were looking at on axis and two unspecified off axis angles (since it was compared to a graph showing the same thing albeit in normalized form). Do you not agree that within those curves there is indeed a tight mirroring from one to another? When talking about off axis spectral balance, less than 1db variation is impressive.

If you are judging my comment by the true on axis response, then I again make the point that we have aj to thank for that as that isn't what he posted.

If in fact I'm mistaken, you could elaborate as perhaps I'm simply not seeing it. I'm open to admitting mistakes as that's how we learn.

The graph you were commenting on is far from your description of "near perfect mirror spectrally of the on axis response".


Below is what you called "on axis response isn't as bad as it appears due to the scale used. +/- 3db from 40 to 10khz isnt really that bad... better than a lot of other 'high end' speakers im sure". Not at all. That $200 Infinity Primus 150 example has a better looking frequency response.


Here's another example of better looking speaker frequency response (on axis, 15 and 30 degrees) than Guru QM10 and yes, it's a high-end.
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post #93 of 168 Old 07-02-2011, 09:47 PM
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Quote:
Originally Posted by diomania View Post

The graph you were commenting on is far from your description of "near perfect mirror spectrally of the on axis response".

I suppose I'm on the short bus on this one diomania because I still don't see what your issue with that statement in that context was, even circled in red. What am I missing? What I see in that region is that the middle curve (so what is this one actually, 75deg or so?) is a consistent 1db or so from the upper curve (60deg?) until 5khz, where the gap closes to essentially zero. The lower curve follows the response of the middle curve quite closely. That's a change of 1db. Shown on a normalized graph such as the one aj posted (and especially at the scale that one used) this would barely register as a visible blip, not to mention likely be inaudible. When talking about off axis, changing only 1db over 15 degrees is pretty amazing, no?

So there has to be something else I'm missing. I'd love to have it explained so I don't make the same mistake again.

As for the remainder of your comments, I agree. There are inumerable examples of speakers both cheap and expensive having flatter on axis responses. I concede that point. There are also inumerable exames having much worse response, including countless high end and very expensive examples. That was my only point there. I don't think that curve if it were the actual on axis response would be terrific, and I think eq could help (especially in this particular speaker since the off axis deviation is so smooth), but in the big picture it isn't that awful either. I think that's all I really said. Look my actual quote again... the words I used were "not as bad... not really that bad." I didn't attempt to say that would make a world class speaker or anything.

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post #94 of 168 Old 07-03-2011, 01:44 AM - Thread Starter
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Quote:
Originally Posted by Bigus View Post

I suppose I'm on the short bus on this one diomania because I still don't see what your issue with that statement in that context was, even circled in red. What am I missing? What I see in that region is that the middle curve (so what is this one actually, 75deg or so?) is a consistent 1db or so from the upper curve (60deg?) until 5khz, where the gap closes to essentially zero. The lower curve follows the response of the middle curve quite closely. That's a change of 1db. Shown on a normalized graph such as the one aj posted (and especially at the scale that one used) this would barely register as a visible blip, not to mention likely be inaudible. When talking about off axis, changing only 1db over 15 degrees is pretty amazing, no?

So there has to be something else I'm missing. I'd love to have it explained so I don't make the same mistake again.

As for the remainder of your comments, I agree. There are inumerable examples of speakers both cheap and expensive having flatter on axis responses. I concede that point. There are also inumerable exames having much worse response, including countless high end and very expensive examples. That was my only point there. I don't think that curve if it were the actual on axis response would be terrific, and I think eq could help (especially in this particular speaker since the off axis deviation is so smooth), but in the big picture it isn't that awful either. I think that's all I really said. Look my actual quote again... the words I used were "not as bad... not really that bad." I didn't attempt to say that would make a world class speaker or anything.

I think this on-axis vs. off-axis discussion is quite clear now, at least for me. It seems that all of you have a point, but you are speaking of slightly different things.

In any case, I would be more interested in understanding my earlier question:

"However, I still have one question, namely, how is the "order" of the roll-off determined? Is it hard-fixed in the amp or in the speakers or is it possible to affect it somehow?"
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post #95 of 168 Old 07-03-2011, 04:50 AM
 
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Quote:
Originally Posted by ephilo View Post

I think this on-axis vs. off-axis discussion is quite clear now, at least for me. It seems that all of you have a point, but you are speaking of slightly different things.

Not at all. You showed the room you are moving to. I gave specific details in my suggestion as to placement, seating, etc....and then, most importantly, what type of speaker to look for...and what type of measurements to look for as well. The Harman (Primus 152) example I showed adheres exactly to what I suggested to you for "controlled off axis"..and specifically HF response. The "Guru" does not. As a matter of fact, the manufacturer of this nearly $3k ($2.7k in 2008) recommends stuffing gauze and bandages around the speaker to ease the suffering and make the sound palatable.
It's up to you to decide whether to take my advice or those of the short bus phone excuse types.
Btw, would you want your room to look like this:?

Because your brain crashed into it's limit and some sheep farmers convinced you that you had indeed created a system as good as any in the world at any price?

Quote:
Originally Posted by ephilo View Post

"However, I still have one question, namely, how is the "order" of the roll-off determined? Is it hard-fixed in the amp or in the speakers or is it possible to affect it somehow?"

The hi and low pass filters on your receiver have fixed roll-off order, as does the amplifier on your subwoofer (usually low pass only).
To be honest, it should be pretty low down on your list of priorities for improving the sound of your current system.
But you're curious, so take a look here.
Best of luck, despite the hijack of your thread by the short bus brigade.

cheers,

AJ
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post #96 of 168 Old 07-03-2011, 06:35 AM
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Quote:
Originally Posted by ephilo View Post

I think this on-axis vs. off-axis discussion is quite clear now, at least for me.

ephilo, just ingore AJ. As you see here, nothing he says can be trusted.

Anyway, do you live close to me? Same country? I'll be more than happy to arrange for an audition of some suitable speakers and speaker/sub combos in your price-range.

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post #97 of 168 Old 07-03-2011, 07:04 AM
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Interesting that aj beats people over the head with the gospel of toole about the absolute benefit of lateral reflections in rooms for improving the subjective enjoyment of audio... and then builds dipoles for himself which reduce lateral deflections dramatically, and recommends a significantly narrower and less balanced dispersion speaker over a wider more balanced dispersion speaker to another member, robbing him of the benefit of those lateral reflections as well?

Audio schizophrenia or just run of the mill hypocrisy?

ephilo, you would do well not to get caught up in aj's personal crusade.

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post #98 of 168 Old 07-03-2011, 07:40 AM
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ephilo, the "roll off" is the combination of electrical and acoustic slopes. Electrical being the behavior of the crossover, and acoustic being the behavior of the speakers.

Let's say you wanted a target of 24db/oct roll off at 80 hz between sub and mains. Two ways of getting there are commonly used. One is to look for a monitor sized sealed speaker that has an F3 (point at which the speaker is down 3db) of 80 hz. Because it is sealed the slope would be second order, or 12 db/oct (second order is a characteristic of sealed speakers... ported are fourth order or 24db/oct). You would the set the crossover in your receiver or prepro or otherwise at 80 hz 12db/oct for a total roll off of 24db/oct.

Another way is to use larger speakers that have an F3 of 40hz or so, and then set your crossover to 24db/oct. Because the larger speaker is relatively flat in the region of the crossover, the total slope will be dominated by the behavior of the electrical component. It is a general rule of thumb to keep F3 an octave or more away from the crossover point to avoid problems.

I suppose you could also look for a small ported speaker with an F3 around 80 hz, leave it unfiltered, and then use the crossover only on the sub side. But ported speakers tend to add significant distortion if not filtered below their F3. Any examples suggested recently that maybe you should avoid?

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post #99 of 168 Old 07-03-2011, 07:46 AM
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Quote:
Originally Posted by Bigus View Post

Interesting that aj beats people over the head with the gospel of toole about the absolute benefit of lateral reflections in rooms for improving the subjective enjoyment of audio... and then builds dipoles for himself which reduce lateral deflections dramatically, and recommends a significantly narrower and less balanced dispersion speaker over a wider more balanced dispersion speaker to another member, robbing him of the benefit of those lateral reflections as well?

Audio schizophrenia or just run of the mill hypocrisy?

ephilo, you would do well not to get caught up in aj's personal crusade.

Go one step further bigus.

Ask yourself, if OxyTheMoron places ALL his truths in the dbt findings of toole, then WHY does he build OB's?

After all, and do please correct me if I am wrong, it has NOT been found by toole in DBTs that OB;s are preferred in any way shape or form?

So why then does he ram down everyone else's throat that they MUST abide by the dbt findings of toole?

Or even why he himself, the idiotic hypocrite and coward that he is, does not blind test his own speakers? That he inputs that data into the computer and when the computer tells him it is fine then he is satisfied? Ie, he does not at any stage sit and listen to the speaker iteration.

He goes by computer fiat.

When he gets the following result

http://www.youtube.com/watch?v=ThTwl1HrFi4

then he retries.

He may even still get THIS

http://www.youtube.com/watch?v=WOdjCb4LwQY

So off he will go again, hoping...HOPING...HOPING that he will finally get THIS!!!

http://www.youtube.com/watch?v=uYhtEBfLMlo


Ok coward, we all noticed you sidestepped the questions. Here they are again


Quote:
Originally Posted by terry j View Post


What questions are we still waiting on?

Why I need to wear a face mask.

ANY discussion of DIFFRACTION problems of my speakers.

Now he has brought it up, HOW we overcome dispersion problems if we use different diameter drivers.

A reference back to HIS that explains how he has overcome those problems.

Whether or not he blind tests HIS speakers.

The results of HIS investigations into the merits or otherwise of room treatments. That means hearing it for himself in his own room.

What acoustic phenomenon the treatment in my room might be addressing.

Why he lies and uses innappropriate graphs to 'illustrate' his point.

Why I need to worry about vertical dispersion.

Why he used THIS graph



and LIED and pretended it went with THIS picture



which is totally untrue.





And just to show the sort of genius I am!

Quote:
Originally Posted by terry j View Post

Those of us who have been around already know he will simply avoid and divert.

Just watch, and enjoy the show!




Quote:
Originally Posted by AJinFLA View Post

Btw, would you want your room to look like this:?



Or this?



Or even this?




cheers,

AJ

Because that is, indeed, the standard my music room will be at when I get around to renovating that room. This one is an exact mirror copy of my music room, just across the hall.

And, being the quirky sort, have NO desire to do anything about the aesthetics just yet, and is WHY I recommend to someone how cheap and easy it is to do the experiment for themselves.

Buy a bag, and throw it around, see what you think. $50 tops. That was my experiment from three (?) years ago. It is so spectacularly successful it has stayed up ever since.

We now await the coward to answer the questions. The objections HE raised till he was called, now he scuttles away.





Conversely, you could have your music room look like this



Note the tiled floors, the walls just in front of and beside the speakers!!! (remember I told you he is a liar and hypocrite? Well, all you eagle eyed scouts, tell us where YOU think unwanted diffraction might emanate from?)

So there ya go ephilo, YOU can decide where the helpful data is coming from, and which data is most likely to help.

(sorry about the off topic..it teds to happen whenever OxyTheMoron decides to ''''help'''' others...such help always comes with a liberal dose of attack from the ankle ferret.

I hear it makes ferrets feel bigger.)
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post #100 of 168 Old 07-03-2011, 08:00 AM
 
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Quote:
Originally Posted by Bigus View Post

Interesting that aj beats people over the head with the gospel of toole

Quote:


ACKNOWLEDGMENT
This paper is the compilation of data from many sources
and the result of discussions with several persons who
volunteered their time to review and comment on the
manuscript. In addition to the Harman International Corporate
R&D Group, Sean Olive, Allan Devantier, Todd
Welti, and Don Keele, the author is grateful to Richard
Small, John Bradley, Gilbert Soulodre, Marshall Buck,
and Brad Gover for their insights.
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[59] M. R. Schroeder, “Statistical Parameters of the Frequency
Response Curves of Large Rooms,” Acustica, vol.
4, pp. 594–600 (1954); translated from German, J. Audio
Eng. Soc., vol. 35, pp. 299–306 (1987 May).
[60] A. Baskind and J. D. Polack, “Sound Power Radiated
by Sources in Diffuse Field,” presented at the 108th
Convention of the Audio Engineering Society, J. Audio
Eng. Soc. (Abstracts), vol. 48, p. 361 (2000 Apr.), preprint
5146.
[61] S. Olive, “A Multiple Regression Model for Predicting
Loudspeaker Preference Using Objective Measurements:
Part I—Listening Test Results,” presented at the
116th Convention of the Audio Engineering Society, J.
Audio Eng. Soc. (Abstracts), vol. 52, p. 861 (2004 July/
Aug.), convention paper 6113.
[62] S. Olive, “A Multiple Regression Model for Predicting
Loudspeaker Preference Using Objective Measurements:
Part II—Development of the Model,” presented at
the 117th Convention of the Audio Engineering Society, J.
Audio Eng. Soc. (Abstracts), vol. 53, p. 83 (2005 Jan./
Feb.), convention paper 6190.
[63] R. P. Genereux, “Signal Processing Considerations
for Acoustic Environment Correction,” presented at the
AES UK DSP Conference (1992).
[64] P. G. Craven and M. A. Gerzon, “Practical Adaptive
Room and Loudspeaker Equalizer for Hi-Fi Use,”
presented at the 92nd Convention of the Audio Engineering
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(1992 May), preprint 3346.
[65] P. Rubak and L. G. Johansen, “Design and Evaluation
of Digital Filters Applied to Loudspeaker/Room
Equalization,” presented at the 108th Convention of the
Audio Engineering Society, J. Audio Eng. Soc. (Abstracts),
vol. 48, p. 365 (2000 Apr.), preprint 5172.
[66] R. H. Bolt, “Note on Normal Frequency Statistics
for Rectangular Rooms,” J. Acoust. Soc. Am., vol. 18, pp.
130–133 (1946).
[67] J. S. Bradley, “Sound Absorption of Gypsum
Board Cavity Walls,” J. Audio Eng. Soc., vol. 45, pp.
253–259 (1997 Apr.).
[68] F. E. Toole, “Loudspeakers and Rooms for Stereophonic
Sound Reproduction,” presented at the AES 8th
International Conference (Washington, DC, 1990).
[69] T. Welti, “How Many Subwoofers Are Enough,”
presented at the 112th Convention of the Audio Engineering
Society, J. Audio Eng. Soc. (Abstracts), vol. 50, p. 523
(2002 June), convention paper 5602.
[70] T. Welti and A. Devantier, “In-Room Low Frequency
Optimization,” presented at the 115th Convention
of the Audio Engineering Society, J. Audio Eng. Soc. (Abstracts),
vol. 51, p. 1244 (2003 Dec.), convention paper
5942.
[71] T. Welti and A. Devantier, “Low-Frequency Optimization
Using Multiple Subwoofers,” J. Audio Eng. Soc.,
vol. 54, pp. 347–365 (2006 May).
[72] T. S. Welti, “Subjective Comparison of Single
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6322.
[73] W. L. Martens, J. Braasch, and W. Woszczyk,
“Identification and Discrimination of Listener Envelopment
Percepts Associated with Multiple Low-Frequency
Signals in Multichannel Sound Reproduction,” presented
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Jan./Feb.), convention paper 6229.
[74] R. V. Waterhouse, “Output of a Sound Source in a
Reflecting Chamber and Other Reflecting Environments,”
J. Acoust. Soc. Am., vol. 30, pp. 4–13 (1958).
[75] R. F. Allison, “The Influence of Room Boundaries
on Loudspeaker Power Output,” J. Audio Eng. Soc., vol.
22, pp. 314–320 (1974 June).
[76] J. A. Pedersen, “Adjusting a Loudspeaker to Its
Acoustic Environment—The ABC System,” presented at
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Audio Eng. Soc. (Abstracts), vol. 51, p. 1223 (2003 Dec.),
convention paper 5880.

I don't recall scripture having these kind of reference...hmmm, perhaps the short bus interpretation did? Gospel eh?

Quote:
Originally Posted by Bigus View Post

about the absolute benefit of (Controlled) lateral reflections in rooms for improving the subjective enjoyment of audio... and then builds dipoles for himself which have (Controlled) lateral deflections

Trig, is that you?

Quote:
Originally Posted by Bigus View Post

and recommends a significantly narrower and less balanced dispersion speaker over a wider more balanced dispersion speaker to another member

Quote:
Originally Posted by AJinFLA View Post

(ephilo) If your budget is $1500ish, I would highly recommend auditioning the highest performance mains in the $1000-1200 range, the rest on center and sub. By highest performance I mean soundwaves, which are measurable, not psychogenic preferences.
Two real world examples:
Revel F12's $1010/pr
KEF Q900 $1100/pr.
Both offer superior off axis response to the typical tragic box designs (like your current speakers)...and thus will sound good in a wide variety of rooms...without the need for resorting to stuffing the room full of bandaids/gauze "treatments".

Beep, beep, hey Bigus, your daily short yellow bus is waiting for you outside.

cheers,

AJ
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Originally Posted by ephilo View Post

I think this on-axis vs. off-axis discussion is quite clear now, at least for me.

Excellent.
Then you understand what a disaster this is and why you would want a design nothing like it for your 13x17 room (btw, almost the exact size (13x18) of the room at the audio show I'm demoing my loudspeakers at....where Terry and Bigus won't be). can you imagine how horrible this thing would sound in a room of those dimensions?
The remote on the DEQX can't fix "detested" delusion apparently.


cheers,

AJ
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Have you considered using some Lubriderm to deal with those rough diffraction issues, Terry? Also, you can probably extend your bottom end with some Astroglide. I think my niece left a bottle somewhere around here. If you can't find it by you I could sqend you the rest of the bottle.

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Quote:
Originally Posted by AJinFLA View Post

The Harman (Primus 152) example I showed adheres exactly to what I suggested to you for "controlled off axis"..and specifically HF response.

You suggested them, not me.

Narrow dispersion (and horribly unbalanced power response). Dipoles have very narrow dispersion as well. Toole's conclusion that you refer to so often was that lateral reflections are preferred over the lack of them. You've made this argument countless times. Now you insert "controlled" into my statement to mean what exactly? The "control" that the infinities and dipoles exert is to reduce lateral reflections. Does toole's et al research show that reducing lateral reflections is preferred, or not? Are you suggesting that there is perhaps some happy medium which is preffered? Oh, that would be fun to post all of the instances where that possibility was raised and you lept in with insult guns blazing.

As for those references, what do they say about these questions? You've read them all of course since you seem confident tossing them around in support of whatever you happen to say at the moment. Which authors cited found a preference for stronger lateral reflections? Which found a preference for reduced but still present lateral reflections? Which found diffusion to be preferrable to reflection as was suggested by toole to be of potential benefit in some cases? Did any test with dipoles or very narrow dispersion monopoles as you suggested to the op which of course significantly reduce lateral reflections? Were they found to be preferred or not?

It appears that you are the expert on toole's research and the dozens of papers that came before that he cites. We will all benefit from your explanations.

Thanks in advance

Cheers

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Quote:
Originally Posted by terry j View Post

Note the tiled floors, the walls just in front of and beside the speakers!!!

Because of the nature of those speakers (dipole moving up to a 90deg monopole) the biggest audible problem in AJ's room is likely actually to be the one you didn't mention: the coffee table between the speakers and the (presumed) listening position.

Too many people do that. I've always wondered why. It is audible, and distracting. Putting the coffee table to the side of the couch is one of those easy, cheap, free things everyone should do.

--
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Quote:
Originally Posted by Bigus View Post

Toole's conclusion that you refer to so often was that lateral reflections are preferred over the lack of them. You've made this argument countless times. Now you insert "controlled" into my statement to mean what exactly?

Quote:


For over 20 years the author and his colleagues have
conducted comprehensive anechoic measurements on
many loudspeakers, and have examined the results of
double-blind listening tests performed on these products.
The results have been gratifyingly similar: loudspeakers
exhibiting certain generally recognizable measured characteristics
consistently achieved high scores in subjective
evaluations [58]. As subjectively interpreted, a smooth,
flat, wide-band axial frequency response, combined with
similarly well-behaved off-axis responses,
up to and including
sound power, appeared to be the desirable pattern.

My turn.

Quote:
Originally Posted by Bigus View Post

Three channels with capable processor are preferrable to stereo l/r even for stereo source material.

Some of the above may be controversial but all is based on sound science and decades if research and experience.

Explaining any of the topics above would require a book in itself

You pulled that out of your posterior.
It doesn't require "a book", just some (even one) links to "sound science and decades if research" corroborating that "Three channels with capable processor are preferrable to stereo l/r even for stereo source material."
TIA.

cheers,

AJ
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Quote:
Originally Posted by DS-21 View Post

Because of the nature of those speakers (dipole moving up to a 90deg monopole) the biggest audible problem in AJ's room is likely actually to be the one you didn't mention: the coffee table between the speakers and the (presumed) listening position.

Too many people do that. I've always wondered why. It is audible, and distracting. Putting the coffee table to the side of the couch is one of those easy, cheap, free things everyone should do.

It must be viewed in context of where the pic came from. You can read the thread here.

Quote:
Originally Posted by AJinFLA View Post

Quote:
Originally Posted by tesseract67 View Post

My coffee table gets booted to the side during listening as well.

Mine doesn't, but there is a plan for that too, as what you are looking at above is stage one of maybe five. I'm only just getting started at the new place. It will be a while before it all gets done.

cheers,

AJ

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Quote:
Originally Posted by terry j View Post

So off he will go again, hoping...HOPING...HOPING that he will finally get THIS!!!

http://www.youtube.com/watch?v=uYhtEBfLMlo

Funny, I come to think about Little Brittain too when reading AJs posts...
http://www.youtube.com/watch?v=qgI5Rx41Sbw


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Quote:
Originally Posted by hevi View Post

ephilo, just ingore AJ. As you see here, nothing he says can be trusted.

Anyway, do you live close to me? Same country? I'll be more than happy to arrange for an audition of some suitable speakers and speaker/sub combos in your price-range.

I am Finnish and am not planning a trip to Stockholm for the time being. But thank you for asking.
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Quote:
Originally Posted by ephilo View Post

I am Finnish and am not planning a trip to Stockholm for the time being. But thank you for asking.

Oh.
You mean the home of:
Amphion

Genelec

And one of my favorites, Gradient

Hmmm. They all seem to share something in common eh?
What could it be? And how does it all relate?




cheers,

AJ

ps. ephilo, not sure how much those cost in Finland, but they are all superb designs by competent designers. Unlike drunk vikes and goat herders
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Got to unsubscribe from this thread as it is turning out to be a waste of my time.
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Quote:
Originally Posted by AJinFLA View Post


My turn.

You pulled that out of your posterior.
It doesn't require "a book", just some (even one) links to "sound science and decades if research" corroborating that "Three channels with capable processor are preferrable to stereo l/r even for stereo source material."
TIA.

cheers

As stated before, when traveling and on my phone it isn't a trivial exercise to paste links to the forum. You're the link king so you shouldn't have any problems finding them. I've already given you directions but I'll be more specific. You'll find a white paper from meridian about trifield that sums up their take pretty well. There are other references to and about trifield as well. From the harman side, there are similar white papers spanning decades documenting their progress on logic 7. That's just the two sources I mentioned previously. To preempt the obvious insults and non sequitors, I'll remind everyone else and especially ephilo who my original comments were directed towards that I said this was controversial, meaning obviously there are two varying opinions about this subject and not everyone falls on the same side. It is obvious that if I make value statements about which is preferred I'm taking a stance with the side that does prefer this approach. And obviously there are those who do not prefer this approach, aj apparently among them. The other thing I said was that while controversial my statements are based on science (they are, the theoretical arguments in support of physical sources vs phantom imaging that is not found in nature, with comb filtering and associated artifacts are really unchallenged) and research (they are, as both lexicon/harman and meridian, two big guns in the field if anyone, have both spent tremendous resources devoted to researching this area over decades with multiple publications documenting their findings and real products that implement this approach based on what their research found was preferred). Aj may call my statements 'wrong' but as usual he is just being a bully and hoping no one challenges his lies.

Btw aj, defining 'controlled' as 'well-behaved'? Could you be any more vague? I should say 'you can surely do better' but we all know you can't. And certainly you don't think well behaved is supposed to mean 'smooth, flat and wideband' as mentioned in your quote as your infinity example is anything but that. Flat off axis? Lol. Up to and approaching power response? Lol. Horrible power response.

So you have yet to even address the question. We'll give you another shot to actually answer instead of dodging, and then you can answer the next half a dozen or so that followed which you simply ignored as well.

TIA

cheers

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Quote:
Originally Posted by Bigus View Post

As stated before...blah, blah...nothing

Cool. Straight from your posterior. Thanks for confirming.

Quote:
Originally Posted by Bigus View Post

And certainly you don't think well behaved is supposed to mean 'smooth, flat and wideband' as mentioned in your quote

Yes, that's what Dr Toole states. Lol. because you can't comprehend it, try asking him for clarification. Lol.

Quote:
Originally Posted by Bigus View Post

as your infinity example is anything but that. Flat off axis? Lol. Up to and approaching power response? Lol. Horrible power response.

It meets that exact description Toole states and JA confirms. Lol.
It has par for the course sound power for a smooth off axis monopole. Lol.

Feel free to show us your speakers with "better" power response than Harmans.
Oh wait, never mind...can't do it form the phone....or too ashamed.

cheers,

AJ
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Still no answers? Shocked.

Is the off axis response of the infinity example flat as toole states is a requirement? Don't rely on the paid words of others. Look at the data you posted in support of your statements and try to use your noggin to analyze it. Is it flat? Even close? Even half as close as the "poor" example you posted?

Answers please.

If toole suggests lateral reflections are preferred over their attenuation, why do you build and suggest speakers that reduce them? Do you agree with toole or not?

Are you incapable of using google? Too lazy? I really don't care.

I said I'm done with the debating as it does seem pointless. But you do apparently have a wealth of knowledge to share. I'm waiting for answers, explanations, anything that is of use to anyone. Maybe we can learn something still.

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Quote:
Originally Posted by Bigus View Post

Three channels with capable processor are preferrable to stereo l/r even for stereo source material.

Some of the above may be controversial but all is based on sound science and decades if research and experience.

Still no answer? I'm shocked. Lol

Quote:
Originally Posted by Bigus View Post

Up to and approaching power response? Lol. Horrible power response.

Still dodging what "horrible" power response is? I'm shocked. Lol

Still ashamed of showing your speakers without "horrible power response". I'm shocked. Lol.
But maybe you'll get past your shame and we'll all learn something. Lol.
Ephilo will know what to spend his $$ on to avoid "horrible power response". Lol
And of course a center for superior 3 ch reproduction of stereo. Lol

cheers,

AJ
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post #115 of 168 Old 07-03-2011, 05:32 PM
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Quote:
Originally Posted by hevi View Post

Funny, I come to think about Little Brittain too when reading AJs posts...
http://www.youtube.com/watch?v=qgI5Rx41Sbw


EXCELLENT work hevi!

I doubt the yanks have any idea of what we are talking about, being as insular as they (mostly) are.

If it ain't from texas we ain't interested is how it goes I think?

So, here is one for you

http://www.youtube.com/watch?v=6N4_-gYyXMM

Hunt down the naked fat ladies for us would you? That should be good for a laugh.



Quote:
Originally Posted by Chu Gai View Post

Have you considered using some Lubriderm to deal with those rough diffraction issues, Terry? Also, you can probably extend your bottom end with some Astroglide. I think my niece left a bottle somewhere around here. If you can't find it by you I could sqend you the rest of the bottle.

Hi chu, have you ever been thanked for your timely injections of humour? If not, then take one from me now would you?

Thanks!

Did we work out it WAS lubriderm?? I had to look that up as it was an american trade term. Of course, it WAS what the name suggested it was....lubrication dermis.

Thought it more likely it was Mrhappylube.

Anyway, finally, we have SOME sort of attempt to address any diffraction issues. Excellent. So, when you said 'rough' were you talking about non-recessed drivers?? That is already covered.

We will wait to see if the ankle ferret will actually address the points HE raised, or will continue to hide.

Quote:
Originally Posted by DS-21 View Post

Because of the nature of those speakers (dipole moving up to a 90deg monopole) the biggest audible problem in AJ's room is likely actually to be the one you didn't mention: the coffee table between the speakers and the (presumed) listening position.

Too many people do that. I've always wondered why. It is audible, and distracting. Putting the coffee table to the side of the couch is one of those easy, cheap, free things everyone should do.

Again excellent. Thanks DS. Funny eh. here we are discussing audio theory, and in a thread in which OxyMoron is participating it comes as a shock and welcome relief to suddenly find proper technical discussion!!

Crazy phenomenon eh?

Nature of those speakers? We have NO idea of the nature. We have not seen measurements, so we have no idea of the technical competency or otherwise of them do we.

The mere 'fact' they are dipoles does not ensure they are a good exposition of the class. After all, from pics, OxyMoron seems able to pick holes in everything else no?

Anyway, I may not have said anything about the coffee table in this thread, but I have certainly raised it elsewhere

Quote:
Originally Posted by terry j View Post

Oh, the coffee table?? Oh dear, and it is such a simple oversight it requires a 'roll eye's"? But thanks for opening our eyes to it, we would NOT want people going around ignoring basic acoustics would we?

So yes, the coffee table in the way, what about the tiled floors?? At least in the other pic it looks like carpet.

What about the ceiling discontinuity, edge diffraction and all that. What are your thoughts there?

that the speakers look to be in almost an alcove, with walls between the listener and the speakers. Surely that might be of more significance than a mere coffee table??

I agree, it looks like a complete dog's breakfast. Oh well, as long as the owner is happy eh?

Gee, I hope people here do not get acoustic advice rammed down their throat by THIS person.



Quote:
Originally Posted by AJinFLA View Post

Excellent.
Then you understand what a disaster this is and why you would want a design nothing like it for your 13x17 room (btw, almost the exact size (13x18) of the room at the audio show I'm demoing my loudspeakers at....where Terry and Bigus won't be). can you imagine how horrible this thing would sound in a room of those dimensions?

Oh, yet ANOTHER jump because you are too cowardly to answer questions.

Now it is whether or not my speakers would fit in ephilos' room?

Maybe, maybe not. Does it matter?

That is NOT what you are supposed to be answering.

Just for information, my room is larger than 9m by 5m by 5m (it has a large bay window on top of that)

So what is that in imperial? Roughly 30 feet by 17 feet with 17 feet ceilings, plus the rather large bay.

Now, back to your questions ferret boy.




See, the funny thing is the most (I'd wager) bear with you (emphasis on bear) because they THINK you have some sort of technical knowledge behind the stink and funk you emit.

Why else do *we* put up with you? After all, we agree with a lot of your thoughts on audio, we too have a bookmark folder and know how to use it, so you are NOT required to fulfill those particular functions. Any and all of us can do that.

So, you are tolerated because of the false impression (increasingly clear) that you have SOME technical chops.

But here it is. The evidence you do not even have that!

You raise a 'technical flaw' in my speakers...diffraction.

Here is your BIG chance!! Centre stage buddy! Show us your technical chops! Go out there and WOW the audience......

spotlight falls on him....turns out to be a sad, lonely figure, stumbling over his words.

So you come back with dispersion problems! Alright, we'll give this loser another try

Here is your BIG chance!! Centre stage buddy! Show us your technical chops! Go out there and WOW the audience......

Little tears welling in the eye under the glare of the footlights...

"yebbut, nobbut (another little britain reference eh hevi!) what about the room size?''

You got nothing! Even I fell for it for a while!! I thought you had at least some technical knowledge, but the emperor is starkers!

I mean we know you little weasly nature, so we also know that IF YOU COULD 'demolish' someone technically, YOU WOULD!!

That you are acurrying away like the noblest of cockroaches when even slightly challenged (hmm, slightly challenged eh? Oh the irony) speaks volumes.

So back to your 'value' to the forum.

You got nothing. Even I am surprised at the emptiness within. So the level of technical knowledge IS on par with and meets the essential 'person' deep inside.

An empty withered husk.


So at the end of the day, you are nothing but a troll?? That's it? That's ALL? A troll?

How else to explain you bringing up a point, some point, ANY point that allows you to spread your venom. It is NOT a point, just a vehicle/method that allows the bile to spread. And we know that because at the slightest challenge, the simplest mention of 'back up your claim' you scurry off to another point, some point, ANY point.

That IS the definition of trolling is it not?

What are the mods doing about this? Why do they let it go on thread after thread after thread?



Do I need to say regarding your inability to answer the questions "Still no answer, we are shocked"??

Do I NEED to say that?
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I'm no speaker designer, Terry, but I think one objection or deficiency he sees in your speakers is why the drivers weren't recessed to be flush with the cabinet. So Lubriderm isn't carried by you. What about Astroglide?

"I've found that when you want to know the truth about someone that someone is probably the last person you should ask." - Gregory House
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post #117 of 168 Old 07-03-2011, 07:34 PM
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Quote:
Originally Posted by Chu Gai View Post

I'm no speaker designer, Terry, but I think one objection or deficiency he sees in your speakers is why the drivers weren't recessed to be flush with the cabinet. So Lubriderm isn't carried by you. What about Astroglide?

Maybe Chu, then again, maybe not eh?

THAT is the whole point.

We ask him, nay invite him, to 'do to town' on the diffraction question with my speakers have we not? I have already conceded and acknowledged that they are not recessed. I have given the reasons why (and if you are neither a speaker 'designer' nor a speaker builder, have a look at the shapes of the drivers. Would I have preferred a simple round shape for the drivers allowing me to recess them?? Of course. Equally, it is clear to see that they are anything but a simple round shape, and I decided that I could not be bothered.)

After that, what have we????? Nothing, except the constant raising of yet MORE points that themselves are not expanded upon.

A troll no?

Ok, he is too cowardly to answer, so let's we address that point now eh? This may help you understand some things a little better??

FROM THE VERY LINK USED BY THE ANKLE FERRET

Cabinet edge diffraction, which is unavoidable, is the result of any obstruction or cabinet boundary (edge) that changes how the sound wave moves across the surface of the baffle. Obstructions are primarily other drivers (midranges or woofers) and baffle edges and protrusions.

A sound wave will diffract when it encounters one of the obstructions mentioned.This interference is delayed in time from the main sound wave and is a function of the distance to the diffracting obstruction (such as the baffle edge). It arrives at the listener position, altering the perception of the sound, since its arrival is close enough in time that you perceive it as being part of the main sound wave.

Delays that are longer (such as reflections from walls) are perceived differently and are not confused with direct sound. You're familiar with this latter aspect of reflections. Box placement and room treatment are used to control that to a degree.


So now, go back to Oxys room pic. Note how close the jutting walls are to the speakers, then see what the likely audible consequences are from above, and how to remedy them.


The Solution

More than one way exists to deal with diffraction. You can mount drivers with an offset from the centerline (useful on its own), but this only changes the distribution in the time and frequency domains; it doesn't actually reduce the amount of energy re-radiated.

Another way is to round over the baffle edge. Although effective, this adds construction complexity. The roundover must also have a rather large radius to be most effective. In combination, offsets and roundovers are useful.

I prefer to use an absorptive material (felt) placed on the baffle after offsetting the tweeter. Why do I say tweeter? Because diffraction is primarily a tweeter concern. The diffraction that affects midranges and woofers is — for the most part – not controllable due to the frequencies concerned. The directivity of the larger drivers also minimizes the influence of diffraction.


And, as we have seen, he even resorts to using the wrong graphs with the wrong treatments to make his position, because as the guru's edges ARE rounded, then all that remained was the ledge. So he used the graph that went with the FULL treatment, not the graph that went with the ledge treated only.

Now, have a look at the pics of my speaker, note the large (largest I could find) roundover on the baffle edges, then note how that then slopes backwards until it meets the curved main box. There are NO straight edges or parallel walls in the entire box except for the very top and very bottom.

Again, a personal aesthetic decision I made. The cabinet is curved, and made from concrete. The sole concern for diffraction is the edge of the 6.5 mid, and the top of the box above it. That is it. Diffraction (per the above) is not a concern for the remainder of the F Range.













Now, go back to the ankle ferrets speaker and positioning



Where are the measures outlined in the link to avoid diffraction concerns? Note the square edges (no roundovers),....well that's about all you can see due to the murky picture with no detail.

So chu, cast YOUR non speaker designer eye over HIS speakers and tell us what YOU see. I have ZERO problem with my speaker design choices being dissected, so don't get the idea that I'm upset you did something of the sort.

What I DON'T get is why the 'subtle validation' of his slimy position occurs. WHY did you not address any of these issues towards the ankle ferrets? HE is the one who brings up stuff to invalidate others. And you (it seems) are happy to play along with that.

Why?


Ahh, astroglide, 'personal lubricant'...yep that certainly COULD double for Mrhappylube.
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post #118 of 168 Old 07-03-2011, 07:47 PM
 
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That is NOT what you are supposed to be answering.

Aye, aye Captain Windows....oh wait...Terry, you've been hanging out with your master Amir a bit too much mate.
Lay off the pipe a bit.
Now take a few nice deep breaths of that country air. Better?
You've got (by your reckoning) a system that would compete with any at any price on the planet. And we can safely dismiss that you are as delusional as the exaggerated hyperbole subjectivists you detest, remember? Shouldn't you be sitting back and enjoying it without so much self doubt?
Simmer down and try to keep your posts a bit more concise. They don't all have to be epic odes and rants.

cheers,

AJ
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post #119 of 168 Old 07-03-2011, 07:58 PM
 
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Originally Posted by Chu Gai View Post

I'm no speaker designer, Terry, but I think one objection or deficiency he sees in your speakers is why the drivers weren't recessed to be flush with the cabinet.

That's the least of Dunny's worries.
I looked at the DEQX manual..and there is no "fix off axis" or "correct polar response disaster" buttons on the remote (where Terry designed a system that could compete with any at any price...on the planet).
What the DEQX does is just create an XO/summed response that is flat at the mic position at some distance on the "design axis".
I think at that point is where he starts randomly fiddling with the buttons, in his "forget to remember" blindish method. Now whether this comes before or after the bandages/gauze begin being stuck about the place, I'm not sure.
I don't think it's relevant either, since we know non-delusional Terry has, in fact, created a system that would compete with any at any price on the planet...as he has since confirmed for us.

cheers,

AJ

btw Chu, make sure to bring your own music you are familiar with on CD.
Otherwise you'll be listening to nothing but Burt Bacharach (including his "Live unplugged" stuff). I imagine Neutron will be checking me for loops too.
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post #120 of 168 Old 07-03-2011, 08:01 PM
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Originally Posted by Terry J View Post

I am actually curious, IS it only me that see's the idiocies of OxyMorons statements?

Or, more likely, is it that for some strange reason others DO see it, yet are afraid to point it out???

C'mon, he's just a kindy bully. A coward. He is also a liar, hence we know he is a coward.

He cannot answer direct questions, because he is a coward.

So I'm having a real hard time understanding why people let him get away with it.

Unless of course it IS only me that see's his idiocies.

I let this one go for a bit to see if others noticed. Seems they didn't.

Terry, it is not only you. It's just there's no point in pointing it out.

Well, anyway I prefer to read Chu's clever, funny posts, particularly those flavoured with hot babe pictures.
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