DML/open baffle for pro sound use

OB_Newbie · « **Reply #20 on:** 4 Nov 2015, 07:50 pm »

Quote from: Gregory Roig on 4 Nov 2015, 02:19 pm

Yes, I too wish that there was more info on DML construction.
Do any of you know much about the newer BMR (balanced mode radiators) (for sale at PE) which incorporate a combination of piston and DML technology. I can't seem to get an answer from PE nor Tectonic Elements about whether you can use multiples of these drivers and still have the benefits of a DML. Wondering if they're protecting their patented ideas and don't want DIYers to infringe on profits... I did find some pro sound panels from Carlsbro called NlightN. But since nxt rights were bought by Tectonic (Elements & Audio labs), every panel out there is no longer in production. Finding used ones is difficult since they are rare. The only ones you can get are in the $7000 range.
Also, anyone heard the Warfedale Loudpanels? Also out of production...
Lightspeed makes a panel designed for classroom enhancement, NXQ. Anyone heard these? $50-- price is right but how's the sound?
Hey, no worries...building my own.

I've heard good things about the Tectonic Elements TEBM65C20F-8 3-1/2" BMR. But consider this a typical full-range 3.5" driver but simply uses bending waves to extend the high frequencies (from 2KHz up)... so you would have to load these drivers like any other conventional woofer. I'm sure the off axis response is fantastic. I don't like boxes so this make this little guy (as good as it might be for a 3.5" full-range unit) a no go for me.

sedge · « **Reply #21 on:** 4 Nov 2015, 08:25 pm »

Just looked up the daex25fhe-4 and noticed that someone had posted a review of their protect with pics,thin ply hanging off the exciter, I made practically the same using thin xps , mine didn't look that good , I used 2x4inch to mount exciter.
Steve

Odal3 · « **Reply #22 on:** 4 Nov 2015, 09:24 pm »

Just curious - How much are the tectonic panels to buy new?

Sedge - yes those stands are really nice. Btw: is your woodpanels rigid enough when playing loud? In my experience with thin birch panels is that they are not rigid enough to support their own weight and becomes wobbly = doesnt sound good with powerful exciters or loud volumes unless some extra rigidity is added to the panels. Thinner larger panels also have a tendency to warp over time. But on small panels such as the ones in the pictures, I'm sure it works much better.

Odal3 · « **Reply #23 on:** 4 Nov 2015, 09:30 pm »

Clarification: large thin panels > 4 x 2ft

sedge · « **Reply #24 on:** 4 Nov 2015, 09:40 pm »

The exciter I was interested in was the hdn-8 ,not my usual choice ,but 50 watts up to a max 100 watts max , screwed on to a ply panel this would be very robust ,I would have preferred a bolt , the exciter would be directly in contact with both sides of the panel , this could still be arranged, also the small footprint on the panel would hopefully stop some of the cancellations in the upper fr above 10k , I don't know how this exciter sounds ,but if it was quite good I would expect it to drive ply panels very well.
Looked at the review's and the video ,the video suggest screwing onto what looks like half inch ply and then screwing onto plaster board in the wall cavity

come on parts express you can do better than that!
The reviews are screwing them on to tables and chairs roof beams and so on

I think they are still trying to get over the fact that in the beginning it was just a toy .
I haven't looked at this site for a while and am happy to see more powerful exciters appearing ,might have to put my hand in my pocket again

Managed to take the ply panels out side for a quick listen before it rained within 25ft the sound was good ,even further was Ok but not loud but still played good LF ,surprisingly .
I re mounted them so they were free floating from a single point ,they sounded very good ,as long as the wind stayed bellow 1 mph .
Am inside in the kitchen 4mx6m approx and listen in to Jean Michel jarre , AERO, very nice.
Steve
Odal3
4inch x2inch wood supporting the exciter

sedge · « **Reply #25 on:** 4 Nov 2015, 10:00 pm »

Odal3
These panels are 3ft2ft and are at the moment hanging from a single damped tape,I have had to turn them down a bit as Jean was playing a bit loud, as I said electronic music comes out vary strong,yes the panels do warp especially after being in the loft,this was another reason for suggesting using the hdn-8 as this wouldn't make any difference,I would always try to have the panels free floating no matter what size ,standing them on the floor or leaning on something will always change the sound and cause buzzing.
Steve

Gregory Roig · « **Reply #26 on:** 4 Nov 2015, 10:36 pm »

Odal,
The small Tectonic retails for, are you ready... around $7.5K! But considering the cost of Podiums that may be about right.

Steve, Did you do your outside test with the big drivers or your usual 10 watters?

sedge · « **Reply #27 on:** 5 Nov 2015, 12:37 am »

Gregor
I only have 10watt units ,I intended to use multiple units per panel for higher out put but didn't like the sound ,to many cancellations on the panel for my liking ,it gives with one hand and takes with the other .
After listening to AERO ,I felt the exciters and they were hot , last night I was xovering the panels at 350hz and they were slightly warm , not a lot, so xo makes a big difference,the panel has less strain too.
As Odal3 points out because you have a powerful exciter this does not mean you can use all of that power,the panel has a saturation point, this is another reason why I don't go too low in the xo point and never use boost eq, a sure way to destroy an exciter,and not a good idea for the panel,especially if it is a polystyrene panel.
Steve

sedge · « **Reply #28 on:** 5 Nov 2015, 12:59 am »

The 2x3ply panels go down to 40hz easily without eq on AERO , but a close mic ed double bass and I nearly lost the exciter bouncing of the back.
Parts express say the hdn-8 reaches 15k this could help modify the peak in response between 10 and 20k?
Or that could just be the response if mounted on a half inch ply and screwed to a wall

Steve

sedge · « **Reply #29 on:** 5 Nov 2015, 01:06 am »

Of cause the hdn-8 might just be a bad sounding exciter ,if anyone has tried it,on anything reasonably good sounding, please let us know.
Steve

Gregory Roig · « **Reply #30 on:** 5 Nov 2015, 02:45 pm »

Forgive if addressed in the other thread (I haven't read all 127 pages!) but have y'all tried thinner plywood? what are the drawbacks? I assume the lightest, stiffest is what we're looking for as in low-mass yet very stiff, right? also, I realize Poly in some kind of a case /box may be in order, but then we're no longer talking open baffle dipole...

sedge · « **Reply #31 on:** 5 Nov 2015, 03:49 pm »

Just had another look at the hdn-8 and in the reviews there is a video of the units installed in their lake house ,if you use your headphones it's as if you are there,and gives you an idea of the sound ,he's screwed them into what looks like 8x2inch beams

it's amazing what you can get away with ,I'm surprised it produces any sound at all

and he's happy with the sound,could be so much better.
Gregor
My panels say they are 3.6mm but they look more like 3mm to me ,as Odal3 says a 6ftx2 ft panel will sag or bend ,but the 3ftx2 ft is ok,there's nothing wrong with floppy wobbly panels as such,it's just that they roll off earlier than the rigid panels in the LF region,as do my 5mm poly panels.
So if you are xo to a LF driver, rigidity is a none issue as long as you make sure the units match for full fr.
Steve

Odal3 · « **Reply #32 on:** 5 Nov 2015, 04:21 pm »

Sedge explains it much better than I can.

In my case, I actually like the bass from the panels and run them as low as I can and only fill in with two subs at the very bottom end for the extra punch plus canceling out some room modes. This is the reason I go with heavier thicker panels but compensate somewhat for it by sanding them gradually thinner towards the edge (just like a piano soundboard)

Gregory Roig · « **Reply #33 on:** 6 Nov 2015, 02:36 pm »

My exciters arrived from PE the other day. Now to find time to experiment with ...

Odal3 · « **Reply #34 on:** 6 Nov 2015, 02:44 pm »

So which ones did you end up with?

Gregory Roig · « **Reply #35 on:** 7 Nov 2015, 03:56 pm »

I have 2 of the Dayton Ultras (DAEX32U-4) and a Thruster (DAEX32EP-4), all 32mm and 4 Ohms and 40 watts.

Gregory Roig · « **Reply #36 on:** 7 Nov 2015, 04:06 pm »

Did you see the pic of the panel that OSSSYVAN posted? Looks like real potential. Also, I plan to use these for acoustic/vocals primarily and would definitely add a sub if needed for more "heavy lifting" . If the panels can do adequately down to about 100Hz great, even 120 to 150 would be workable with a sub.

Gregory Roig · « **Reply #37 on:** 7 Nov 2015, 04:07 pm »

Sorry, Osssyvan's pic is on the "NXT rubbish" thread FYI.

OB_Newbie · « **Reply #38 on:** 7 Nov 2015, 04:08 pm »

That is a good start to see if you dig the magic panels as much as we do...

Are you building an array for PA work? I have had good luck with the Thruster but others on the PE TechTalk have not. Ultra's for me have not been very reliable and PE has not been very operative getting me replacements for the last 2 that have failed but sure they will come through as they always do...

OB_Newbie · « **Reply #39 on:** 7 Nov 2015, 04:20 pm »

Quote from: Gregory Roig on 7 Nov 2015, 04:06 pm

Did you see the pic of the panel that OSSSYVAN posted? Looks like real potential. Also, I plan to use these for acoustic/vocals primarily and would definitely add a sub if needed for more "heavy lifting" . If the panels can do adequately down to about 100Hz great, even 120 to 150 would be workable with a sub.

100Hz is not a problem with even a panel is the 18"X24" range I would estimate.

yeah, I saw OSSSSYVAN's pics. very nice indeed. I know that Odal likes the ply panels but I favor XPS for sensativity and more detail. its a preference thing. These stands are just for testing different panels. I'm dying my panels black, framing them and covering with grill cloth. They will look like these Magnepans...

I sure do like the looks of the ply panels though...