[sfdoddsy]

Now you're being disingenuous.

[lowtech]

... BTW:  there are supposed to be no references or denigration of religion here.

You seem to confuse my position with anger.  <snip>

Dave

Which is precisely why I removed all references to religion in my post (that you didn't quote).

Perhaps you're a really great guy in person, but we have not met... so I'm just going by how you carry yourself on this forum.   

And... all I'm interested in are some facts that substantiate some of the claims made in this thread about a set of servo dipole woofers.  Some of that you have provided.  Thanks again for that.

[dBe]

Now you're being disingenuous.

No, sir.  I am being very direct.  There is no equivocation to my post.

World English Dictionary
disingenuous  (ˌdɪsɪnˈdʒɛnjʊəs) 
 
— adj   
 not sincere; lacking candour 
 
disin'genuously 
 
— adv   
 
disin'genuousness 
 
— n 

[dBe]

Which is precisely why I removed all references to religion in my post (that you didn't quote).

Perhaps you're a really great guy in person, but we have not met... so I'm just going by how you carry yourself on this forum.   

And... all I'm interested in are some facts that substantiate some of the claims made in this thread about a set of servo dipole woofers.  Some of that you have provided.  Thanks again for that.

Thank you for the deletions.  I replied before they were made.  For the record, I am not a Druid.

I am what I am.  I'm very direct.  I do not believe or ascribe to "politically correct" crapola because it does not allow people to get to the crux of the issue(s).  I do believe in being open, honest and sincere.  I call them as I see them.

Often words on the web do not convey the manner in which they were proffered.  Too often ideas (the holder's) are read into the posts of others without the condition of understanding necessary for decent conversation.  A LOT of that has gone on here and we tend to get caught up in the tenor and fervor of that conversation without trying to fully understand the manner in which they were offered.  I admit to being guilty of this in this thread.  It is too easy to "take sides" in what should be a really good discussion that has stooped to the lows that this one has.  For crying out loud, this is a thread about Maggies and subs!  It is not and should not be a diatribe about someone's "feelings" about others with no basis in experience or reality.  Like I said early on, I started watching this thread thinking that nothing good can come from it and sure enough, here we are.  Sucks.  Plain and simple... it just sucks.  I fully expected moderation to step in, but there you go.  Expectaions, hopes, wishes and dreams are oftem misplaced and unfounded.

No, I'm not a bad guy.  I haven't eaten a baby in months.

Dave

[Early B.]

No, I'm not a bad guy.  I haven't eaten a baby in months.

 

[sfdoddsy]

No, sir.  I am being very direct.  There is no equivocation to my post.

World English Dictionary
disingenuous  (ˌdɪsɪnˈdʒɛnjʊəs) 
 
— adj   
 not sincere; lacking candour 
 
disin'genuously 
 
— adv   
 
disin'genuousness 
 
— n

Now now, give the full definition:

Adjective:   
Not candid or sincere, typically by pretending that one knows less about something than one really does.

[THROWBACK]

Thanks for the discussion thread about dipole vs. monopole slam. I'm still not sure I get it, but it corroborates  what I have been hearing. Now I'm wondering if it's possible to still get the "jump factor" through manipulating an equalizer.

[dBe]

Now now, give the full definition:

Adjective:   
Not candid or sincere, typically by pretending that one knows less about something than one really does.

OK.  Two can play:

dis·in·gen·u·ous (dsn-jny-s)
adj.
1. Not straightforward or candid; insincere or calculating: "an ambitious, disingenuous, philistine, and hypocritical operator, who ... exemplified ... the most disagreeable traits of his time" (David Cannadine).
2. Pretending to be unaware or unsophisticated; faux-naïf.
3. Usage Problem Unaware or uninformed; naive.

--------------------------------------------------------------------------------

disin·genu·ous·ly adv.
disin·genu·ous·ness n.
Usage Note: The meaning of disingenuous has been shifting about lately, as if people were unsure of its proper meaning. Generally, it means "insincere" and often seems to be a synonym of cynical or calculating. Not surprisingly, the word is used often in political contexts, as in It is both insensitive and disingenuous for the White House to describe its aid package and the proposal to eliminate the federal payment as "tough love." This use of the word is accepted by 94 percent of the Usage Panel. Most Panelists also accept the extended meaning relating to less reproachable behavior. Fully 88 percent accept disingenuous with the meaning "playfully insincere, faux-naïf," as in the example "I don't have a clue about late Beethoven!" he said. The remark seemed disingenuous, coming from one of the world's foremost concert pianists. Sometimes disingenuous is used as a synonym for naive, as if the dis- prefix functioned as an intensive (as it does in certain words like disannul) rather than as a negative element. This usage does not find much admiration among Panelists, however. Seventy-five percent do not accept it in the phrase a disingenuous tourist who falls prey to stereotypical con artists.

The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

At what point do you quit?  Me?  I'm done.

[JohnR]

I was using a Peak/Hold RTA tool that captured all of the frequencies within a certain time window defined by the selections made of measurement parameters on the tool itself.  This was in 3 second intervals.  If you know the piece of music at all you would know that this is a valid time slice to get the true frequency dependent response consist for that particular piece of music.  The 18Hz tone lies at the bottom threshold of the DAC used at the time which employed no brick wall filters to distort the readings.

Dave, are you able to run the relevant section of the track through an FFT? Might be interesting to see what's actually on it...

[Nyal Mellor]

Nyal,

I am sorry that your post seemed to have gotten overlooked. It was not. I agree with everything that you said in your first post. You have a great product and I think it is the best product of its kind and have said so before.

When you read what I have posted about your product or any other of its kind please know that I am one of the guys that you mentioned here in this statement that you made.

The digital that I am used to is at the top level of DAC's. And for me I can't go backward. And it is hard for me to recommend to my customers that are shooting for the best performance possible.

When in fact you do reach the levels of thee top level DAC's, plus digital crossover capabilities, then I would in fact recommend the product to my customers that are interested in trying something like that, and (hopefully) sell them drivers that they can use it with.

Sure makes sense, though most of us do not have the funds for a dac that performs to dcs, total dac or dad standards, much less being able to afford multiple channels of it so that the passive crossover can be removed from the speaker and the crossover is done digitally. So for the rest of us the deqx is a great value package, all things considered... 6 channel dac, preamp, speaker correction and room correction for either 3.5 or 5.5k. With it you can put together a killer active 10-15k system that will wipe the floor with the traditional passive xo speakers and electronics upto maybe 50k. Not saying it can't be bettered with top notch dac, speakers etc. It's just expensive.

[rythmik]

Once again, this 'SPL statement is meaningless. Presumably you were listening to music, which has a range of frequencies. So the measurement was of the overall output of the speakers. No-one is doubting they can easily hit 105db or whatever somewhere. What some of us are doubting is whether they can hit 20Hz specifically at those levels. As you claimed.

You guys should back off now. What is a typical room?  Have you considered that your room may happen to have a -3db null at 20hz. By itself, it is not too much.  The RMAF room happens to have a +3db peak at 20hz. By itself, it is not too much. But the difference of the two can be 6db there already.  What else can add to this sort of difference?  How about the RMAF room is closed and your room is open to another room (maybe)?  On top of everything, what if your driver happens to have a Qts value of 0.5 (instead of 0.7) and Fs value of 14hz instead of 20hz that AE quote. That sets your 20hz output back even more.  There is a variability of driver parameters and you take the AE data for granted. Have you double check it?   I sent the SW12-16 driver to Red Rock Acoustic for Klippel test. Again this is typical of your data vs my data. We can be loopy here without any meaningful conclusion.  I asked you to visually inspect the excursion that you see from your AE driver at 20hz, care to do that?

[jtwrace]

I sent the SW12-16 driver to Red Rock Acoustic for Klippel test.

I was going to ask what the cost of that is but it doesn't seem so bad.  I'm a bit surprised.

http://www.redrockacoustics.com/loudspeaker_testing_pricing.php

[Danny Richie]

Dave, are you able to run the relevant section of the track through an FFT? Might be interesting to see what's actually on it...

Let me get the kids off to school this morning and I'll take some measurements in my listening room.  And I do have the track in my play list.

[rythmik]

Thanks for the discussion thread about dipole vs. monopole slam. I'm still not sure I get it, but it corroborates  what I have been hearing. Now I'm wondering if it's possible to still get the "jump factor" through manipulating an equalizer.

Some describe slam as "mid bass slam". It is a result of peak around 70hz to 120hz.  On our PEQ control, turn it on, set the frequency to 80hz, bandwidth to mid, and gain to 3db.  If that gives you the right direction, you just need more of that with other EQ.  Our hearing is very insensitive to the bottom end. So the more obvious effect is either the higher order harmonic distortion or FR emphasis in midbass region.  SRS lab has a patent on how to make small subs sound big. The trick is intentionally inject distortion to the system.

Another direction to look for is the phase alignment.  Do 3 plots: one with front speakers only, one with subwoofer only, and one with both turn on. Tabulate the response give you better pics.  Maybe your room as a room mode peak at the crossover point and that masks the effect that the sub and front speakers are phase misaligned. 

In terms of bigger amp for SW12-16, our kits are designed as a whole, meaning we know how much power the driver can take without destroying them.  If we pick A370 for a particular kit, that means that power has almost maximimze the excursion utilization. Going to the next level power can spell trouble.

[rythmik]

I was going to ask what the cost of that is but it doesn't seem so bad.  I'm a bit surprised.

http://www.redrockacoustics.com/loudspeaker_testing_pricing.php

The process is all automated with Klipple equipement. Patrick now has an intern to do the process for him.

Back to the issue of Mms. The method of getting Mms is by putting a known mass to the cone and then remeasure the change of Fs and from there deduce the value of Mms. Even Patrick admits this process is prone to error.  But it does not affect the actual SPL output, fs,  or Qts value calculation.  Fs stays the same, meaning if one got the wrong Mms, it also leads to wrong Vas value. But that is all. The T/S mechnaical parameters actually produces a RLC network on the equivalent circuit of the driver impedance curve. For mesurement the actually RLC values there is no need to know the mechanical parameters. 

[Danny Richie]

Okay fellows. The info that you asked for is coming.

I pulled the grills off of the lower section of the Super-V's because under real hard play this pair will rattle the grills. They are held on magnetically.



I also wanted to keep an eye on woofer movement when I drive these babies hard. I want to push them to near X-Max.

To give this some context I would like to point some things out.

In the room we had at RMAF, where we took SPL measurements with a hand held device or two, we REALLY loaded the room. So we weer getting some room gains. But another thing to note is that the lower section of the Super-V was only having to keep up with the upper section being played with a 15 watt tube amp. Granted the upper section has 97db sensitivity so output levels were still high. But I think there was a lot left from the servo subs. I think we could have driven them even harder.

At my house I have played the Super-V with the big 280 watt tube amps pretty hard. I have played them much harder than the 15 watt tube amp could play them, and the servo subs still matched their output easily.

A could of things to note also about my listening room. It is decent sized at 17 feet across by 23 feet deep and has 9 foot ceilings. There is also a large opening to the back right corner to the dinning room. So you'd think my room would suck up bass pretty well. Especially with those large tube traps in all the corners and foam panels on the walls. And maybe it does soak up some energy down low, but I will be honest with you guys. I get a 3db to 4db peak in my room from about 25Hz or so and down. I see it in all my room measurements of big speakers. LS-6's and LS-9's for instance have a little peak in that region in my room. And anyone that has been here for an audition will tell you that I have really deep bass in my room.

That being said, on with the measuring...

Oh yeah. Nyal, my big mono-blocks (pictured) are 50k by themselves.

[Danny Richie]

First up was some music tracks. I wanted to get a feel for what the peaks might be in music.

The mic was set in the middle of the room right behind my couch at center seat position. This is in a good neutral area of the room. Along the back wall it gets bass heavy. I didn't want to be there. I wanted to show listener position levels.

I used an FFT measurement with 1/6 octave smoothing. I did a few RTA measurements too and they looked almost identical.

First up was a track from Blue Man Group caled Endless Column. A couple of minutes in that is a continual deep hit with a long sustain that will be easy to capture. It rocked the house! But not as low as I thought.



That overblown deep note overshadows everything in the music. Centered at 41Hz it hit 105. 

Funny thing when watching a real time analyzer while listening to music is that I am always surprised that my listening preferred listening levels are not that loud. With a low distortion system that can hit high SPL's very cleanly it can really sneak up on you.

More coming... This will take a few minutes to get uploaded and explain so hang on.

[Danny Richie]

Next up was a track that Dave mentioned earlier. We were seriously rocking our RMAF room with this one and I still can't believe the level of wall movement out in the hall way. It's a wonder we didn't crack some sheet rock.

Dave, Pete goes pretty low but the fundamental is not as low as you thought. And I can slightly hear it.

Oh yeah (quick edit here) the track is from Pete Belasco and is called Deeper. It's the second track on the album.



This one centered at 26Hz and hit 112db. The woofers were still really clean, but I think I was near the limit. Also with this type of measurement the peaks really pop so catching it at the peak is not so easy or consistent. I'd say give or take 2 or 3db for accuracy and take away 3 to 4db in that range to my room gain.

I caught this one on that same track hitting 113db.



It was really hitting the room hard but that frequency range did not sound that loud because of how low it really was. It doesn't overpower the music like it appears in that quick capture I grabbed.

In an average room with no room gain like mine I think one can expect a solid 105db peaks down low.

On to test tones.

[Danny Richie]

So I set up a 20Hz sine wave and took my remote with me over to the speaker and cranked it up to what I felt like was right at its X-Max with no notable distortion.

Then I took the measurement and got 105db. Looks like when I saved it the measuring line had moved. So I don't have the line on it. Sorry about that. I did have it lined up on it, but missed it on the save.



I also noticed that the time and date are wrong on this computer again. It never keeps up with the time and date for some reason.

Another funny thing I noticed with this measurement was what things in the room rattled. I have a few rattles to fix now...

And I couldn't hear the fundamental too well, but the room was ALIVE.

[Danny Richie]

For the rest of the measurements I left the volume the same to see what the levels would do.

Next up was a 25Hz test tone. Looks like it hit 109db at 26Hz by the measurement. I saved it with the measuring line on it this time.



I left the 20Hz measurement for reference.