[zygadr]

Welcome back mightym!.
Yes, a lot HAS changed over all this time. Shellacced C.C. seems to reign supreme in the panel material department so far..........very natural and uncoloured sound.
Method of mounting has changed too : the exciters load is not placed on the panel but on to a spine as you have mentioned.
There are a number of ways to do this as long as you stick to the Monacor placement recommendation.

[emailtooaj]

Welcom Back Mightym!! Would really like to see what your Sketch Up looks likes. Sounds like an interesting idea!!

Thought I would just kick for a few and say what's up to everyone!

Super stoked today , just got my revised parts back in.
Meet an awesome machinist locally and he has been a life saver!! I finally have all the parts I need to start molding and casting the components needed to start building and testing
this new exciter design.
My earlier go around need some tweaking with dimension changes.
But I hope these newer parts are the ticket! 

I will go ahead and wind the new coils to 8 Ohms each. Figured if a 4 Ohm load is needed, well...just use 2 and wire it parallel 

With the holidays coming up, I won't be able to start building anything till I get back.
For those who celebrate Christmas, have a Merry Christmas and have a great time with family and friends!!!

Peace

[zygadr]

PICS, ..................PICS,..................WE WANT PICS OR NOTHIN' IS TRUE!

[mightym]

Thanks for the warm words gents.

I do have a question that would help me to place an order with PE for some goodies, including drivers.

Can anyone give me a ball park efficiency rating with say a 30Cm wide by ~42Cm tall single layer of CC and One Exciter, then with additional exciters?  I'm trying to source components that will allow me to not have to attenuate a large efficiency difference between the panel and the dipole woofer doing the bottom couple of octaves.

John

[emailtooaj]

Just for you Zy! 

[zygadr]

mightym, you would be looking at relatively low efficiency of around 86 - 87 db with one exciter. If you paralell + series wire another three you may gain another 5-6 db.............maybe. You will also gain some efficiency by using a spine to take the load of the panel.

emailtooaj!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!WOW!!!.......................LOOKING GOOD!!!

[mightym]

That's a big help on the efficiency numbers.  It's a bit higher than I would have guessed, but I can work with that info.

Thanks!

John

[emailtooaj]

emailtooaj!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!WOW!!!.......................LOOKING GOOD!!!

Thanks Zy.

Just waiting for the molds to set up and then I can start casting the parts 

Hope by beginning of next week I can start assembling them and see what happens.

Can anyone give me a ball park efficiency rating with say a 30Cm wide by ~42Cm tall single layer of CC and One Exciter, then with additional exciters?  I'm trying to source components that will allow me to not have to attenuate a large efficiency difference between the panel and the dipole woofer doing the bottom couple of octaves.

Wish I could help answer that John. Since I haven't had the chance to use CC yet, Zy and others would have a better handle on that.

I can say this though with HDPE....
I've been able to notice a substantial difference when I used a thin coating of epoxy across the whole back of the panel, as opposed to just using epoxy around the exciter mounting locations.
Lower frequencies...60hz-150hz, had a nice boost with the back panel coated with epoxy.
I would assume that the epoxy is helping the panels sound to be more uniform and helping to eliminate some dead spots...in turn, making the panels efficiency higher.
I made some quick panels for a friend with one exciter each and epoxied the whole backs. They sounded just as loud as my current ones, which has 2 exciters each and has the epoxy only in the exciter mounting locations?!
Both of the panels where the same material and dimensions.

Hope that helps some John????

Peace

[emailtooaj]

Well... Here are the finished Molds.
Turned out pretty good 
Next Step... cast some parts and begin assembly.

Peace

[Abelma]

H

[j gale]

The 4 in the center is the Monacor placement. The sound is cleaner than placing them on a vertical line. When I made the change the improvement was immediately noticeable both to me and my wife. I didn't think that having 4 as close together as they are would be better but it is. See post 1755 for the link to the Monacor placement.

[Abelma]

T

[wesh6da]

Hi, all.  I've been pouring over quite a bit of this thread the last few days, and ended up ordering some Dayton exciters to build a pair of panels.  I have a set of OB's currently, but would like to get into a set of these.  If I built the panel frame on top of a 12" paper woofer(in OB, of course-no boxes allowed) from my current set up, could I get by with say a 1' x 2' panel and keep the low-midrange response?  They don't need to play too low as the woofer starts solidly in the 30Hz range and starts to roll off very smoothly at around 300Hz.  I would like to keep them somewhat small, as the big OB's haven't exactly been warmly received by my wife no matter how good they sound. 

I noticed there's talk of shellac and epoxy to treat the CC with.  Any preference for one or the other or are they close to the same?  And are you guys treating the entire piece of CC or just the flutes and back, leaving the front natural?  Glad to see the CC won out...love the sound of paper cone speakers.

Love the thread...this is by far the most info anywhere on the web for DIY panels.  Thanks for all your hard work 

[j gale]

Just my 2 cents. Small panels are a waste of time. A large panel (say 2'x6' minimum) is truly full range. No woofer needed. A large panel is coherent with a sound stage to die for. Big sound and lifelike image and fills even large rooms with believable sound. Nothing like a 12 square ft tweeter, mid, and bass with the coherence that brings. Trying to marry a woofer to a small panel introduces a xover phase differences etc. Forget small and ugly and go for big and beautiful.  For Abelma I don't remember any loss of bass with the Monacor config.

[Abelma]

I

[wesh6da]

Just my 2 cents. Small panels are a waste of time. A large panel (say 2'x6' minimum) is truly full range. No woofer needed. A large panel is coherent with a sound stage to die for. Big sound and lifelike image and fills even large rooms with believable sound. Nothing like a 12 square ft tweeter, mid, and bass with the coherence that brings. Trying to marry a woofer to a small panel introduces a xover phase differences etc. Forget small and ugly and go for big and beautiful.  For Abelma I don't remember any loss of bass with the Monacor config.

Thanks, jgale.  I figured there would be problems, just wondered.  Hope to start on them next week sometime.  I'm pretty excited about these things as the OB's are getting tired and it's time to try something new. 

[zygadr]

wesh6da......................you will not be dissapointed..............j gale has wrapped up their sound very clearly.
I tend to snigger a bit when other audiophiles brag about their Magneplanars, Electrostats, line Arrays and O.B.''s. If only they could hear what a DML panel can do.......................they would rip their hair out for the money they have outlayed!!

[wesh6da]

Well, I put some smaller trial panels together this evening, and wow!  The lack of a sweet spot is incredible and the stereo image seems to follow around the room, even outside of the speaker boundaries.  That's a huge improvement on the OB's.  Bass is well defined but falls off due to the smaller size but over all very good. 

The good vintage amp decided to quit working last night so I had to go with the cheap-o receiver so this may have hurt the bottom end as well, but midrange clarity was incredible.   

So far so good.  Going bigger very soon. 

[exspec]

So I have come back to this thread yet again... its like a beautiful woman, you can't help but keep looking and wondering "what if..."

Looking at the transducers on the PE site, I recall being told the one I had selected was sufficient for playing with:

http://www.parts-express.com/hiwave-25mm-soundpax-exciter-turns-virtually-anything-into-a-speaker--309-149

My concern is that I see it only goes to 13.5khz, which is still nice and high, but am curious if the traditional speaker philosophy of multi way would work with these NXT type speakers, specifically, would a smaller transducer be capable of reaching higher and acting as a tweeter in a two way? The 11 and 13 mm units are about half the size of the ones linked above, and seem to indicate that they indeed go to 20khz. They have lower power handling and 16ohm load though. Is it possible to wire 2 into an 8 ohm load and run it as a tweeter panel? Or is this totally excessive, taking away from it all, and not needed? Here is one I was looking at:

http://www.parts-express.com/hiwave-hiax13c02-16-rh-13mm-classic-exciter-16-ohm--297-2101

Now assuming this is hasn't been tried and is worth investigating, the next question is "would these work as multi way on a single panel?" My thinking is that no it wont, so now how would we divide, orient two panels to act as one source? The Magnepan way is to run a thin vertical tweeter along the side of the main panel. Since sweet spots are less of a concern with these NXT types, this could be pulled off to good success, no?

Another contingency was possibly experimenting with a dipole planar tweeter to fill the higher frequencies if I should notice any lack of highs.

[zygadr]

Hi exspec............and welcome back!
I am very busy at the moment with arrangements for building our new dream home.

Very quickly though, do not pay much attention to frequency response claims as they are very much dependent on panel size and panel material.

The smaller exciters you have mentioned will not add more highs as a rule in general. What is more important is power handling and a good panel material as previously mentioned.

If you really think you need more highs, use the peizo cone out of a peizo tweeter and glue this to the back of the panel(about 6 inches from the edge of the panel. Two cones would be mounted as a ''mirror pair''.Each cone is simply wired to the exciters in parallel with no crossover required.

Others are welcome to chime in here with any ideas.

By for now