[OB_Newbie]

Got a couple off home improvement projects I need to complete before experimenting more with the panels. I still suspect the muffled sound you are hearing is the xps board you are using. I wonder if some shellac or something similar would help. ?? At least that is what I will try when I have a chance.

Hey Odal!  Could very well be the panel material!  I have 3/4 in. to try and might go with shellac though I bought a gallon of glue yesterday when I bought the 4x8 sheet. 

I'm listening to Cowboy Junkies and the harmonica sections certain would NOT be characterized as sounding dull in any way... very fast, dynamic and even biting... all unequalized at the moment.  I hope I'm not misleading anyone because I can't explain it well enough.  This has always been the problem in explaining sound. 

I hope I can make progress here but have to figure out the design and actually have to take time from listening to build a new set of panels!   

Later! 

[OB_Newbie]

OB Newbie, firstly, don't think for a second that a DML will act like laser beam death rays at high frequencies and provide pseudo acoustic imaging tricks that so many audiophiles just can't live without despite all their direct radiator shortcomings.

I find it strange that your attempt at DML 's produces a sound that is ''veiled'' (??????) and ''flat'' (?????). There is something amiss there as DML's are the opposite to this in my opinion.
Also, you are using a SQUARE (  ) panel that is very thick and run by a more or less average exciter.........probably not a good match? Your room size, together with their positioning within that room,  will also have a great effect on how these panels work.

 You say your panel material is pink, and others have mentioned blue?? .
 I came across the light blue stuff recently at the foam supplier and can say that it is definitely NOT the same stuff as VH GRADE EPS that I have been using (it was named ''XPS :  SOVIRA BLUE''???.  I don't know if this other stuff is what is causing anomalies out there, but I wouldn't be surprised. It is definitely NOT ''EPS''.

By the way, the sound DOES come from the back of the panel.......it is supposed to and is what contributes to the magic of panel speakers.OB speakers that are primarily forward firing, are a different ball game, so forget about comparing the two systems and concentrate on improving the DML's.

Once again on the subject of wide versus narrow panels to improve imaging.................you are not dealing with shoe box speakers on stands............the width of the panels do not act in this way (thank God! ).

May I suggest you read ALL of the reviews found on the Podium website(as well as comments throughout this thread) so that you can fully understand that the DML is the only speaker type that can do what other speakers, including panel types, just can not. This is especially evident when compared to the sound of live music, which is what we audiophiles strive for.

Rob.

Hello Rob,
As I'm sitting hear listening to music I thought I'd read a Podium review.  Been posting most of the night so needed a change of pace.

http://www.stereomojo.com/Podium%20.5%20Speaker%20Review/Podium.5SpeakerReview.htm

Here are a few excerpts from a Podium review I read many, many months ago and it was the first one I found tonight.  As I read over I got a feeling that the reviewer was eluding to some of the aspects that I was hearing... not exactly of course... but it kinda hit home for me in some aspects.

On imaging : "While there is plenty of detail, it is not spotlit and pinpointed the way conventional speakers can be. Individual instruments and voices in large ensembles are not sharply delineated, but neither are they smeared. They just don’t pop out at you. With some speakers, it seems you can tell whether the timpanist in the last row is wearing boxers or briefs. Not so here, but you will be able to hear the timpani sound much the way it actually sounds in a real symphony in a real symphony hall."

The aspect that is the most distracting to me... sound from behind the magic panels :
"The word “behind” is significant because the overall presentation is more to the rear than most speakers. Male and female soloists are portrayed in the same plane as the speakers rather than projected in front of them. Accompaniment is still well separated from them, just further to the back than normal. Everything else, from small ensembles to large scale bands and orchestras are also cast as if you are seated a few rows further back in the hall. There’s nothing inherently wrong with that, it’s a matter of personal taste and a factor of which you should be aware."

Imaging and why live recordings might sound better.  This is in reference to bass performance but live recordings sound much better to me via the panels by and large : "This weakness is most prominent in close mic’d electric bass such as what one might hear in studio rock, reggae, electronica and other dance genres. In studio recordings by Vic Wooten, Stanley Clarke and the like are not well served. They are often recorded via a direct in to the mixing console. However, bass instruments that were recorded live as part of a small or large ensemble and which are placed further back in the mix fare much better."

Why I'm interested in what panels might offer : "If there were one design that the Podium’s most resemble it might be open baffle, though most open baffle models use some sort of enclosed cones for the bottom end while the rest of frequencies are not enclosed and radiate in free air."  The bottom end of an OB is the best part.  Combining OB and a boxed bass bin doesn't sound good to me.  The bass quality of an OB and how it loads the room is soooo different.  ALL OPEN BAFFLE IS THE ONLY WAY TO FLY in the dynamic speaker world.   


Differences...choices... :  "Because of Dr. Katz, we all now have another golf club in our musical bags of speakers. Some people will listen to these and immediately turn their nose up and their ears off. Others will listen and declare these a revelation and just what they have always been looking for."

Others observations :
"I agree, they take some time to adjust to their sound and positioning. Get them right and they are a clear window on any classical or acoustic event. I have podium ones."

"Quite simply - they played acoustic instruments and voice as though they were in the room.This was not an impression of ,or approximation of the sound but the sound of real instruments.This is obviously an overused concept and of course there were subtle imperfections which gave the game away - but i can honestly say they redefined what i thought possible from reproduced music."

"I thought the 1's were seriously handicapped, with a very coloured high-end (no wonder with the weight of the panel) and very strange tonal balance.

"They did not sound like any other speaker I ever heard, which was something 'special', but I really missed any real presence, dynamic contrasts and something approaching pin-point imaging."

Interesting... going to read more tomorrow to hear more observations but its late so time to sign off...

[zygadr]

Hi Ob Newbie.
I have mentioned once before that I had a forum member from overseas visit me to hear my first version of the DML's when I was using black Gatorfoam.
You talk about "dynamic contrasts"????........ ........when I played a percussion blast from a CD I have, he nearly fell off his seat!........and so did I!
Instead of listening to rock music, borrow some real audiophile cd's of a different nature to hear what this technology can do. Listen to Yo-Yo Ma's "SOLO" (cello on it's own in a fantastic open acoustic) to hear dynamic contrasts and imaging. You want details to pop out at you?.........it's all there and every time I listen to it, there is something new to discover and it is NOT "spotlit"........that is unnatural.........more "hi-fi" than "real-fi".

Anyway, I don't mean to create arguments , but there is a lot more going on in a DMLthan first meets the ear

[xit]

Yes, ............but as far as I know, Podium have never released a "layered sound" loudspeaker.As a guess, they probably had significant trouble making it work due to the two totally opposite technologies and the sound they produce.

Having attended numerous symphonic concerts, I have never noticed "imaging" as a real event occurring on stage. What I have noticed is the diffuse and homogenous sound field with lots of reflected energy (I actually heard the Tuba notes reflecting off the concert hall roof!!!)and some direct sound..........very similar to the effect of a DML in action.

Hi all

there are several "layered" sound products, maybe i'll give a try to theses
I like Naim stuff and have some electronics of them powering my pistonic loudspeakers
and i found this speaker really nice (but the price is ... a bit expensive)

http://www.6moons.com/audioreviews/naim5/ovator.html

for the diy   http://www.tectonicelements.com/bmrs/

and the infamous   http://layeredsound.com/product.php#pa


OB newbie you're right, after some hours, the ears sets up for this different way of music reproduction,
and it sounds good, one can really enjoy music with this new way of hearing the recordings
I'm also agree that the type of recording and the techniques used to record influence the way the panel sing

Also going back to point source / pistonic systems is also appreciable ... but it might depends of what you listen at
there are features that i can't find in the DML like the music "slam" (you can't find this on classical and jazz)
And also i can more enjoy the full spectrum bandwith with my 35Hz/35kHz speakers
That's why i think my DML project will be completed with ribbon tweeter and a good old bassbin
(moreover at certain frequency in the lows the panels starts acting like a piston whatever you can do)

But the dml makes some aspects of the music more appreciable, also there are not a lot of serious room
response problems like pistonic speakers, and the listening is not fatiguing at all.
And i'm like all of you exited by this and want to know where it can be pushed and maybe find my audio nirvana ...

[j gale]

Hi, For you guys that have only recently started experimenting I want to pass on something that I have learned. Over the years of OB's, horns, and others you learn quite a bit about what works  well and why. That body of knowledge tends to close your mind somewhat to possibilities you might try if you didn't,t have that knowledge. I have found that what you think you know often doesn't apply with these panels. Since 2009 my assumptions based on knowledge built up over 40 yrs. have been shot down over and over. These panels don't play by the rules, so sometimes it pays to try things that you KNOW won,t work because with these sometimes it does. One EG., EPS . I always ended up rejecting it because of It's plastic sound. I thought I knew that any coating would not change it enough to satisfy me. It took me 6 years to get over my ignorance because of what I thought I knew.

[OB_Newbie]

Hi Ob Newbie.
I have mentioned once before that I had a forum member from overseas visit me to hear my first version of the DML's when I was using black Gatorfoam.
You talk about "dynamic contrasts"????........ ........when I played a percussion blast from a CD I have, he nearly fell off his seat!........and so did I!
Instead of listening to rock music, borrow some real audiophile cd's of a different nature to hear what this technology can do. Listen to Yo-Yo Ma's "SOLO" (cello on it's own in a fantastic open acoustic) to hear dynamic contrasts and imaging. You want details to pop out at you?.........it's all there and every time I listen to it, there is something new to discover and it is NOT "spotlit"........that is unnatural.........more "hi-fi" than "real-fi".

Anyway, I don't mean to create arguments , but there is a lot more going on in a DMLthan first meets the ear

Check that Rob...percussion is amazing... best I've ever heard... bar none!  And I'm listening to a piece of 24x24 foam insulation!  Just nuts!

I listen to a lot of different music but mainly jazz esp. Getz, Webster, Mulligan, Mingus, Miles Davis and many of the classics, contemporary jazz but also a lot of acoustic music such as Jack Johnson, Cowboy Junkies, Mazzy Star to name a few.   I have a box of Telarc classical disks from the 80's and early 90's when I sold high end gear. 

Do you have any favorites with heavy percussion Rob?  I had a really good Telarc symphonic recording back in the day that started with large bass drums and a range of Timpani drums that had just awesome attack and decay.  If you have any similar records... man... I'd love to hear them on the panels!!

I listened to the Cowboy Junkies 3 times through last night and was loving what I was hearing and thought they were really opening up but  throwing in my standby Getz or even the fantastic Muddy Waters Folk Singer was a bit disappointing.  2 step forward, 1 step back...   

Good call on Yo-Yo Ma though... can't play the Junkies all night again tonight.  Always enjoyed Yo-Yo's original Bach recording and the newer one from the 90's is even better in my opinion.  I'll have to dig them out... should sound fantastic even running the panels full-range with no bass support... might be another late night... thanks Rob!!!   

 

[OB_Newbie]

Hey fellas,
Going to start new panels tomorrow but am still wondering about the panel material and could use some guidance.

So for the guys in the US and probably Canada, what is the brand of EPS or where did you get yours ??? 

Also, how are you guys mounting the panels to the frame (if you use a frame!!) ???

Just a few words would help to narrow down the next steps to a few more proven approaches. 

Many thanks,
Rich

[zygadr]

Hi, For you guys that have only recently started experimenting I want to pass on something that I have learned. Over the years of OB's, horns, and others you learn quite a bit about what works  well and why. That body of knowledge tends to close your mind somewhat to possibilities you might try if you didn't,t have that knowledge. I have found that what you think you know often doesn't apply with these panels. Since 2009 my assumptions based on knowledge built up over 40 yrs. have been shot down over and over. These panels don't play by the rules, so sometimes it pays to try things that you KNOW won,t work because with these sometimes it does. One EG., EPS . I always ended up rejecting it because of It's plastic sound. I thought I knew that any coating would not change it enough to satisfy me. It took me 6 years to get over my ignorance because of what I thought I knew.

AMEN!!!!

Hi Ob Newbie, gosh yeah!.....those Telarc AND Reference Recordings are something to hold on to forever!!!!
The absolute most INCREDIBLE, MIND BOGGLING, SUPER FANTASTIC percussion recording I own is :

''PERCUSSION XX''.......Jonathan Faralli........''ARTS'' label : 47558-2    ''audio Phile series'' 24/96 recording.
If any of you out there can get hold of this recording, you WILL BE BLOWN AWAY!!!! ...............but beware!!..............so might your speakers!!!!

[zygadr]

Have just unpacked my 6 X 2 foot, 20mm thick VH EPS sheets that were sandwiched by a strange version of EPS that I have not come across before!!
I will describe these cover sheets in full when I get time. To all..........you may be surprised....

Rob.

[sedge]

Jgale
At the moment I am revisiting some of my older panels to see how they perform with the new sanding and pva method,as I type this I am listening to the new pink Floyd album (an Xmas present)on a 3mm thick 12x9 inch partially clamped panel it has a good response above 250HZ and very flat above 2.5k to 20k and this is only being held together with tape and g clamps ,I have them sitting on top of an old pair of Ditton 44s but just using the 12 inch bass units xo at 300HZ, I usually let the panels run down to about 100HZ, I would just like to say I am not championing small panels I am just saying that they do work and that if you have a small room and the other half does not want a 6ft panel you don't have to loose out on the panel sound.
As for the presentation of the sound from the large and small panels,having a large panel in a small room IS like a massive pair of headphones, and if you switch between your headphones and the panels they should (if done properly ) sound very similar.
With the small panels in a small room you will hear more depth and space around the panels and a little more delicate sounding maybe ,but you will not (as yet) get the full shock and awe of the larger panels.
The small panels do sound good with drum solos ,better than most speakers I have heard ,but they just can't match the shear scale of the large panels ,swings and roundabouts again I'm afraid.unless you can get an OB to  do the same but then your getting into large panels again.
OB_newbie
If you would like a little more presence from the front of your 25mm thick panel I would suggest you try my method of sanding a cone type shape on the front side of the exciter of about 2inches wide and leaving about a 5mm thickness to the exciter,this gives the panel a more detailed and intimate sound ,I have mentioned this before on this site but maybe you have not read through all the pages,things tend to get lost in all the posts .
Steve

[sedge]

The panel on the right will give you an idea of what I do to the exciter area to give a more intimate sound ,a bit like having a 2inch driver in the centre of the panel,and yes it is in the centre of the panel,but only because it is a very old panel before I knew any better ,but it still sounds good,mainly because of the thinning of the panel in the exciter area
Steve

[sedge]

To do this I cut the bottom off an aerosol can and glued on some sandpaper ,you then just press the dome part into the panel and twist ,it is better to do this before you glue on the exciter to make sure it is in the centre,but if it's just a test panel you could just guess.
Steve

[j gale]

Sedge,  Thanks for your comments re: small panels. It's not that I am against them per se, but as you so nicely put it they don't have the shock and awe of larger ones. I would hate to see anyone miss out on that because of a mindset moulded by the little speaker on a stand experience. I also think that a 2'x6' or 2.5x6' panel is so much better looking. Thanks for the info on how you made your cone shaped depression. I was about to ask. I will give it a try. I have noticed that with some of the exciters that have a vent hole through the magnet that it seems to contribute quite a bit to the sound behind the panel. I wonder about the effect of a small hole 1/4 " or smaller through to the front side of the panel centered on the exciter. I think eventually it will be possible to voice your panel to suit your own taste.  Jim

[OB_Newbie]

Jgale
At the moment I am revisiting some of my older panels to see how they perform with the new sanding and pva method,as I type this I am listening to the new pink Floyd album (an Xmas present)on a 3mm thick 12x9 inch partially clamped panel it has a good response above 250HZ and very flat above 2.5k to 20k and this is only being held together with tape and g clamps ,I have them sitting on top of an old pair of Ditton 44s but just using the 12 inch bass units xo at 300HZ, I usually let the panels run down to about 100HZ, I would just like to say I am not championing small panels I am just saying that they do work and that if you have a small room and the other half does not want a 6ft panel you don't have to loose out on the panel sound.
As for the presentation of the sound from the large and small panels,having a large panel in a small room IS like a massive pair of headphones, and if you switch between your headphones and the panels they should (if done properly ) sound very similar.
With the small panels in a small room you will hear more depth and space around the panels and a little more delicate sounding maybe ,but you will not (as yet) get the full shock and awe of the larger panels.
The small panels do sound good with drum solos ,better than most speakers I have heard ,but they just can't match the shear scale of the large panels ,swings and roundabouts again I'm afraid.unless you can get an OB to  do the same but then your getting into large panels again.
OB_newbie
If you would like a little more presence from the front of your 25mm thick panel I would suggest you try my method of sanding a cone type shape on the front side of the exciter of about 2inches wide and leaving about a 5mm thickness to the exciter,this gives the panel a more detailed and intimate sound ,I have mentioned this before on this site but maybe you have not read through all the pages,things tend to get lost in all the posts .
Steve

Thanks Sedge... that's a fantastic idea.  I do notice a small improvement in presence when I flip the panel so this will be a better choise than having the exciters and wires exposed to the listening position.   

I'm listening (as I type) to 2 x 6 ft (.75 inches thick) panels (not coated with glue:water mixture) and again just propped up against the high-back chairs and they do sound very nice even with the undamped resonances from such a setup. 

Have to let them break in, listen more before I make any determinations, but the bass of a larger panel does sound different than and other speakers I've heard.  I was hoping that they would be as lightening quick as the 2x2 panels but only go deeper but I'm not sure at this point.  Still have the very nice presentation, don't get me wrong here, but the improvement in low freq. response seems the bass quality seems more of a resonance nature.  Again... these panels are untreated and not supported by a frame system that could drastically change the quality of the lower bass and how its generated but since you have tried more sizes, shapes, thicknesses than anyone (I saw the pile of panels you have tried... wow!) and wonder if you have an opinion of the bass quality of a large panel vs. a small panel.

Just wondering if an approach might be to run...say... a 2 x 4 foot panel and use an open baffle (U frame) bass section?!?  I really like the idea of a full-range panel that doesn't require a sub but just curious what your opinion of small vs. large panel are... just a quick comparison and your expert assessment perhaps?!? 

So many directions to go into and any guidance from the DML crowd is just a HUGE time (and money) saver.  Any feelings on the topic??

Thanks in advance!
Rich 

[OB_Newbie]

AMEN!!!!

Hi Ob Newbie, gosh yeah!.....those Telarc AND Reference Recordings are something to hold on to forever!!!!
The absolute most INCREDIBLE, MIND BOGGLING, SUPER FANTASTIC percussion recording I own is :

''PERCUSSION XX''.......Jonathan Faralli........''ARTS'' label : 47558-2    ''audio Phile series'' 24/96 recording.
If any of you out there can get hold of this recording, you WILL BE BLOWN AWAY!!!! ...............but beware!!..............so might your speakers!!!!

Off to eBay and Amazon I go... Thanks for the recommendation Rob!

[j gale]

OB_Newbie,  I am presently using 2'x4' panels with 15" Augies in an H frame. The combination works well. The 2'x4' need the help on the bottom. When I used 30" x 60" cardboard panels they didn't need that help. Neither did the similar sized birch panels I had. To my ears some form of OB bass is the way to go if the panels need help, U frame H frame etc seems to blend better than sealed subs or similar.

[OB_Newbie]

OB_Newbie,  I am presently using 2'x4' panels with 15" Augies in an H frame. The combination works well. The 2'x4' need the help on the bottom. When I used 30" x 60" cardboard panels they didn't need that help. Neither did the similar sized birch panels I had. To my ears some form of OB bass is the way to go if the panels need help, U frame H frame etc seems to blend better than sealed subs or similar.

Thanks Jim for the reply.  Augies.  Nice.  I really enjoy my OB bass panels and completely agree that any other bass loading would not blend well with these panels.  There ought to considerably more output from the bass panels and high passing the panels to remove large excursions should clean up what these panels do best.

If you don't mind me asking, as I'm sure its stated somewhere in the 108 pages of posts, what is your recommended method to suspend the panels?

Been listening to the 2'x6' panels all day and do like the presentation but man, they are imposing.  My wife was not happy when she got home today from work.  Hopefully 2' x 4' will keep me off the shit list.  At least for a short period! 

   

[sedge]

J Gale
Just had a quick listen to my rear hole on the exciter , but can't say I can hear a lot above the sound of the panel ,so I held a Mic close and placed my finger over the hole but didn't see any change in fr response ?
Years ago I did make a large hole in the centre of the exciter panel area but it sounded phased and had a bad fr response,not what I was hoping for.
OB newbie
The easiest way to mount a panel for testing is to just hang it as seen in the photo using 1 inch masking tape back and front ,a strip of foam can be stuck to the tape if it starts to buzz .
This way you can change panels very quickly and the panel vibrates freely.
Large panels will have a slight overhang ,you can easily hear this if you play music with large amounts of LF and press pause .
Steve

[j gale]

One easy way is to just suspend them with a couple of elastic bands. For my 2x4 panels I cut a 16" circle to sit on top of my H frames, attached a 1x3 frame, narrow edge toward the panel about 15"x48" so that it doesn't show. I put short screws into the back side of the panel 1" below top edge 15" apart, 2 more near top of the frame (longer screws) small elastic band about 1" in diameter lets the panel hang free and nothing shows. EPS is so light that not much is needed. Even the speaker wire holds the panels from swinging. Several ways of doing it are shown in this long thread. I prefer not to restrict the movement of the panels. I have in the past attached them to a frame using pieces of foam backer rod which did restrict movement a little but it didn't seem to be a problem. I haven't worried much about a permanent arrangement because the experimenting becomes an addiction. My wife is used to it and likes the sound of the panels too. Rich I think your chances of staying off the shit list are slim at best. It sounds like you are getting hooked too.

[j gale]

Sedge, Thanks for the info re: exciter hole. It was just an impression I had. I seem to rember in one of the Podium reviews talk of plugging some of those holes to regulate hi frequency energy. Your info about the hole through the panel probably saved my current panels from being stabbed through the heart