Listening Get Together

Re: Listening Get Together

The HP is recommended to avoid damage to the transducers, not a requirement if you don't mind damaged transducers.
The 36 volt measurement showing about an 8 dB dip in response at 70 Hz (generally indicative of a serious phase cancellation which usually can not be fixed with EQ) was on the BigE website in the same "War Ad Slick" that recommended the HP.
As best I can tell by the attached graph is that the sensitivity (based on 8 ohms) is around 98dB. Not exactly "ground breaking".

And the proposed "response to 20 hz" is actually 18dB down from the main response.

Not many people call 18dB down "response to".

Maybe I am reading the graph wrong.
 
Re: Listening Get Together

This thread is going no-where fast, perhaps it's time for everyone to cool it until some valid measurements can be presented, anything else is just pointless dick wagging.

I will say that I have utmost respect for Art, his cabinet designs perform better than some other respected DIY designers out there. Ivan's credentials don't even need to be mentioned, I'm sure we're all quite aware of the value he provides to this forum.
 
Re: Listening Get Together

I don't know the people who did the measurements.
I have e-mailed and asked for them.
Aside from tracking them down and physically taking it from them, what else do you suggest?

So you don't know who they are-yet you have emailed them-how is that?

So you are ready to post these "measurements"-are they valid? How do you know-if you don't know who they are?

So what sort of "measurements" were taken. What were the conditions of the "measurements"?

Did they tie into your system? If not is it just RTA measurements?
 
Re: Listening Get Together

The testing did not occur for several reasons. The primary one being that a change in the cabinet design started just after I posted that. A single driver solution for a cab that previously required 2 drivers to create the "vortex". That has since been perfected after much burned plywood. Then a modest change increased output by 3db. It's a product under constant evolution. Who's isnt?

I have stated before in the thread, I am waiting for spring. Testing behind my shop for real numbers is pointless. Testing inside the shop creates artifacts. Learned my lesson, no graphs until I can do it outside. My test area is 20 acres of nothing. Closest house is 1/8 mile away, closest highway is 1/2 mile away, lightly traveled. As soon as it's warm enough and dry enough for me to get down there I'll mow it down and have at it. With appropriate software.

In the meantime the MinE25's will go out to the evaluators here who have volunteered to listen. That's all we ask. 5 minutes is enough.

As far as measurements at the listening GTG, well, it was for listening. Who wants to listen to test tones all afternoon?
I'm getting even more confused.

You or Doug stated earlier that the Big E designs were pretty much immune to room modes and reflections.

If that is the case-then why not just do the measurements inside?

What sort of problems do measuring inside (besides reflections and room modes) cause? That is generally the case for measuring outdoors.
 
Re: Listening Get Together

Doug, I'd advise you to stop posting on professional forums until you have measurements or at MINIMUM a finished product.

This thread is the kind of thing that gets taught in PR classes as the "Do not do this!" examples.
 
Re: Listening Get Together

just about every post in this thread breaks down to "who's that trip trapping on my bridge."
It's fun to watch in that slow motion car crash kinda way but it's seriously played out and I convinced the BigE guys have been playing us all and having a good laugh over it.
 
Re: Listening Get Together

So you don't know who they are-yet you have emailed them-how is that?
As stated before... I contacted them through the person who brought them.

So you are ready to post these "measurements"-are they valid? How do you know-if you don't know who they are?
So what sort of "measurements" were taken. What were the conditions of the "measurements"?
I don't have them yet, so I don't know.
I asked for everything that they did, along with descriptions.
Whether they send them or not is up to them.

Did they tie into your system? If not is it just RTA measurements?
Yes, they did tie in
 
Re: Listening Get Together

Doug, I'd advise you to stop posting on professional forums until you have measurements or at MINIMUM a finished product.
This thread is the kind of thing that gets taught in PR classes as the "Do not do this!" examples.
If you had payed attention, you would know that I am not the manufacturer nor do I personally have the ability to provide measurements.
You would also know that there are several finished products and several more that are still being developed.
 
Re: Listening Get Together

I'm getting even more confused.
You or Doug stated earlier that the Big E designs were pretty much immune to room modes and reflections.
If that is the case-then why not just do the measurements inside?
What sort of problems do measuring inside (besides reflections and room modes) cause? That is generally the case for measuring outdoors.

Would you guys accept measurements that were done inside?
 
Re: Listening Get Together

Leland,

It only takes a matter of minutes to do on axis measurements indoors or out, not all afternoon.
And listening to pink noise makes it easier to hear what a speaker's dispersion is like than listening to music, though I'd only need the time to walk from on axis to off axis before music listening would commence.

Unless it is actually raining, snowing or too windy I test outdoors year round.
Not doing outdoor measurements during the winter is going to insure a slow product evolution.

Purchasers of loudspeakers don't want "constant evolution", they want finished products that are consistent and perform to specifications.
Big E is already advertising finished products, yet it seems from what you write they are still in the development stage.

Art

We are to the finished product stage on some of the cabs.
It's really loud around my shop. I can do it certainly. But I will have no confidence in them. What's train noise, or main street noise, 2 blocks away, or cars on Crawford right in front of the shop, a heavily traveled street. The railroad tracks are literally 50ft from the shop, on a busy day -they run every 15 minutes or so switching cars. Idling engines many times sit by the shop for 20-30 minutes.

I can certainly do a pink and a walk around testing for dispersion. But an spl or response test there will be pointless. Inside, who's going to believe them? Room artifacts, room gain, bounce. It needs to be outside 1/2 space in an open area. I am completely convinced that's required to adequately test. Once I have those as a baseline, I can do inside testing and see accurately what the room is doing to the sound. If it should turn off nice enough melt the snow and dry out the pasture sooner I will get after it. I've lived here a long time though, and it's more than likely going to be a while. March is always wet. I will look for an alternate location.

One of my concerns is and has been that I want the testing to be defensible. I've seen the assaults in years past on testing protocols. Although it probably wouldn't be any worse than what's going on now. I do regret posting that graph, because I could not defend it, and the cab was not ready.

I appreciate the tenor of your post. Constructive criticism. Valid points.
 
Re: Listening Get Together

Dick,
The BigE inventors, Leland, and myself have decided that your quote here has earned you a BigE B.S. Contest Honorable Mention award in the form of a free BigE B.S. coffee mug.
If you would like to PM me a shipping address, I will get that shipped out to you. (yes, seriously)

You have been Curmudgeonly Skandahoovianed® (a form of smiting). The "prize" is an endless loop of Norwegian ice fishing songs and children's accordion lessons, courtesy of Mr. Rees. ;)

Here's my arms-length advice, Doug. Stop. Let Leland do the lifting here.

Have fun, good luck.

Tim Mc
 
Re: Listening Get Together

From page 1:
Of course the inventors have taken extensive measurements, but I was just speaking from my point of view.

Also:
They don't interact with room modes like a normal speaker. In the gym, not a null to be heard. In the bar, 1 null about a foot wide behind 1 pool table in a random location. About a 3db drop in bass, I could just barely hear it. The meter was how I found it. We split the subs, the power alley was about 3 inches wide on the dance floor. You had to move pretty slowly to even find it.

Also, I never saw an answer to Jeff Babcock's well thought out questions back on something like page 5. I really think that until you guys have some valid data, this is a big waste of everybody's time.
 
Re: Listening Get Together

"The inventors have explained to me that because of the way the vortex generates sound, that it does not interact with room modes and reflections in the same way that conventional speakers do."

B***S***.

Oh my god, I can't wait to read though the whole thread !!!!!!! But this has got to be for sure the best comment so far!!!!!
 
Re: Listening Get Together

I would really love for some industry professional to chime in and say something but that just isn't possible because no demo systems have been provided and neither has any measurement data. If I need to do any time traveling I will contact BigE as soon as possible, as I think if I crawl though their horn I might pass the event horizon and be able to reach 1987 again ;-)
 
Re: Listening Get Together

W
It's really loud around my shop. I can do it certainly. But I will have no confidence in them. What's train noise, or main street noise, 2 blocks away, or cars on Crawford right in front of the shop, a heavily traveled street. The railroad tracks are literally 50ft from the shop, on a busy day -they run every 15 minutes or so switching cars. Idling engines many times sit by the shop for 20-30 minutes.

I can certainly do a pink and a walk around testing for dispersion. But an spl or response test there will be pointless. Inside, who's going to believe them? Room artifacts, room gain, bounce. .
Most real measurement platforms offer various forms of time windowing-sample averaging etc. Some are better than others-for example with TEF you can be running a shop vac next to the mic and it will give you good data-YES I have done it.

With others you can do more averages-so the noise starts to "fall out". Each time you double the averages you gain 3dB in S/N ratio.

Why are you worried about reflections and room modes-if the cabinets are "immune" to those?

The phase trace will show/tell a lot in that regard.

And of course SPL measurements are only good if the mic has been RECENTLY calibrated (like right before the test)-NOT calibrated when it was shipped.
 
Re: Listening Get Together

Sorry, in all the vitriol I just neglected answer this.
Hi Leland or Doug,
Looking at the youtube videos, a couple of questions...

1) The "dual 18 test prototype model 218SLVX" cabinet in the one video shows rear facing drivers which are presumably firing into a reasonably long pathway. Typically when creating this sort of design, were I the designer, my goal would be to locate the drivers such that the output from the front and the rear of the driver could arrive simultaneously and in phase with each other in order to sum for increased output. It would seem to me that the configuration shown might be capable of significant output, but that multiple arrivals and a long path might negatively affect punch and usability in the higher end of the output spectrum (ie above 100hz). I am sure the designers have their reasoning for such a configuration, but I am curious.


The problem you are describing with phase and arrival times are one of the things that led them down this path. On their web page for free is the bandpass box that started the whole thing. It has great punch, but also has all the attendant problems inherent in that design. TBH, it was pretty much a happy circumstance that led to the design. "Let's do this and see what happens". They are not degreeed engineers. But both have backgrounds that are complementary to this, in practical applications, work and hobby.

I have resisted saying this, because I know what will happen. Phase plots look like a tornado. According to the phase plots, these cabs should sound awful. Incredibly awful. They don't. The "punch" from even the tops is enormous. Punch and impact are defining qualities of the sound. Even the little MinE25 will thump your chest. The GC46 could be run completely without subs in small/mid club settings, non dj work. Something in happening in the phase that completely fools the microphone. We believe it's because the information is packeted, and the differing arrivals are out of phase. You can't hear it, but the microphone can. Audio trickery? Maybe, but does it matter if it achieves the goals of improved dispersion, punch, and quality of sound?


2) The "LC8 Line Array PA Top" has a rear facing HF driver loaded into the "Vortex Waveguide", which presumably does some gymnastics with the audio passing through it (at the very least turning it 180deg). I have experimented with curved horns and found "smear" (low tech talk for multiple arrivals) to be evident even into the low midrange with such configurations, getting progressively more noticeable as the frequency rises. I can appreciate that BigE says that they are overcoming some traditional perceptions, but I would be interested to hear a more detailed account as to how this issue is addressed. The descriptions on the website of an "event horizon" are pretty vague, invoking reference to quantum mechanics and theoretical physics concepts. What does this waveguide actually look like? Are they actually making a real physics claim, or is this just marketing?

8)~:cool:~:cool: Kind of both marketing and a physics claim. I can't describe the waveguide without their approval. It should not work, according to conventional loudspeaker design. It violates several precepts, especially in horn design. When I first saw into a box even after hearing them I still called bullshit.

The hf section loaded directly into the waveguide has been relegated to specialized applications. I'm using that design for surrounds in the local theater. It's a more diffuse sound, and we decided for PA use a direct firing hf section was needed. Once again, it shouldn't work, at all, and it does, very well.

Steve and Tom have quirky senses of humor. They're also uber geeks. Thus the descriptions. But really, event horizon is fairly accurate. There is a point in the nearfield where you can hear the cabs switch to farfield losses. It's one of the things I'm determined to figure out with the outside testing. Where that occurs, and possibly why. It does not seem to be frequency dependent at least by ear. I know you continue to hear everything all the way back. Happens all at once, across the spectrum.


From BigE - "
transmit auditory information beyond line of sight with minimal loss. The Vortex Event Horizon will wrap around objects, obstructions, and up to boundaries providing a self-adjusting nature to the nearfield."

I am curious as well regarding how the above claim might impact reflection and especally further information regarding diffraction properties, which are commonly known to be frequency dependent, ie
d sin(theta) = m lambda for nerds. If you have actually overcome the diffraction equation you will stir waves in the science community. And how could you derive a coverage pattern in this case?


The diffraction issue has come up in conversations among us many times. And it is possible that it will stir waves. The don't interact with room modes like a normal speaker. Mostly because they don't seem to interact very much. Or at least in a different way. Anectdotal. I know how you all love anectdotal. I run them in my shop normally with just the radio, NPR news. Because if I play music I get captured and end up listening to it rather than working. The front half is walled off with a standard 36" door into the wood shop. Speakers facing forward, away from the door. No change in sound back in the wood shop, reduced volume, but qualitatively no change. Which TBH concerned me for a live setting, feedback issues. After using them live for the first time, it's not an issue. Just follow regular placement rules to minimize the chance and you're golden.

I know it seems like we don't know what we're doing. Countless hours on the phone and via emails working through the effects, trying to quantify what is going on in terms of accepted theory.