you could fit this into an H-Frame cabinet. cheap bass seems very attractive.
Ok ... Should have been obvious, mils are often used as shorthand for mm in Aus. Your mils are often called thous here.
Oh for worldwide consistent units!!
Tagis would you please post the address for your omni loudspeaker blog? I have listened to a number of omni designs such as the balloon/globe types and find them very interesting and I would like to follow along. Thank you.
you have a myriad of options for diaphragms using polyester silk screen material available is a wide range of weights and weave sizes. This as lots of internal loss built in and makes a good sounding diaphragm. Hope this is of interest.
the Quad 63 does not generate a travelling wave, it simulates an expanding wave using delayed lines to drive the panel sections which are driven as pistons. Panel sections decrease in area from the largest area for the bass to end with a small area piston to provide high frequency dispersion.
The Highwood Audio panel did do a pretty good job of recreating a travelling wave panel speaker. We could place a 1/8 inch B&K condenser microphone at a right angle at the outer edge of the panel and measure out to10 KHz. Dispersion was uniform generating a reasonably even hemispherical wavefront. This sort of radiation pattern does however light up the room with both floor and ceiling bounce which has to be considered, you can have too much of a good thing.
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you would get come extra floor bounce to add to the overall output of the system same as the difference between a woofer up off the floor in a cabinet and being close to the floor in the same cabinet. a panel on its side will present a larger surface are which the floor will reflex.
Museatex of Montreal was the name of Ed Meitners company which merged with Highwood Audio in Calgary after Highwood had to part ways with Sumo Audio. So the Highwood Audio speakers were sold under the Museatex Melior banner.
Moray's dip into the past has me re-reading the old posts 😵💫
Made me idly wonder what the results would be if a ply panel was tissue/paper et al stiffened on the rear face more than the front so the rear waves were dampened more than the front.. It'd be like shifting the neutral axis rearwards....
Thoughts...???
Eucy
Made me idly wonder what the results would be if a ply panel was tissue/paper et al stiffened on the rear face more than the front so the rear waves were dampened more than the front.. It'd be like shifting the neutral axis rearwards....
Thoughts...???
Eucy
I would assume that the parchment sounds this way is due to a combination of the cotton fiber and wood pulp in its structure. There are so many materials to try and combine. Consider Fostex in Japan who make full range drives. Over the decades hey have produced so many different types of papers for cone material it is amazing. Interesting to read your comments on modern parchment. Have you tried parchment on any lo grade low density expanded polystyrene which is on the warm side and rolled off sounding?The reason you dont see much NXT products is because they catered mostly to "Pro/live audio" instead of Audiophiles/DIYers. They are two completely different marketing catagories. Most of NXT products werent sold in the common hi fi audio stores but rather Music/Instrument stores hence the lack of popularity in the audio enthusiast community. Occasionally NXT would license there product to other companies like Teac but failed to build anything note worthy.
If my memory serves me correctly I warned yawl about Tech Ingredients. Its not my problem if you dont want to listen to my advice.
You never read NXT patents before? I find that odd, since you are the patent king?
Hmmm I just recently mentioned skins in my previous post. Anything touching the surface of said panel material becomes the skin and will take on some of the skins sound signature depending on the skin used. For example paper has a warmer/duller sound but it will sound more accurate. While Aluminum will have a brighter more lively sound. Many factors involved its not as simple as one might think. If your core material is already warm sounding to begin with then you wouldnt want to use paper unless you want it to sound really warm, you have to find the RIGHT combination which again boils down to personal preference. Like Goldie locks and the three bears you dont want it too hot or to cold but "JUST RIGHT".
Anyone ever hear a "CERAMIC", type of tweeter or woofer? Ceramic is very clean and articulate sounding but also can sound very dry. The SKIN material that sounds like a ceramic driver is one of my many preffered skins is "PARCHMENT" paper. Here is another tip> One side of the parchment paper does not sound the same as the other side. You have to listen for yourself which side you prefer. Ahhh man giving away to much secrets.
so forgive me for not knowing, please which panels are these?these panels need a tweeter as much as i need another hole in my head
this is another bright sounding cd.
these panels can handle anything.
still having fun
steve.
if I had to choose I would pick the ply as the proplex has a somewhat subdued character though the spectral balance is indeed close.
I would think that DE used as an admixture to PVA would help to extend the high frequency transmission of a coated panel surface especially around the exciter mount. Well worth experimenting with.The point is its not soil or rock in there natural form. Shellac and wood grain fiber filler are not in there natural form. Its used to harden the panel at the same time damping the panel like a layer of skin.
Diatomaceous Earth is not in its natural form nor is Chitosan.
Its like trying to adhere an exciter to D.E.
Hi moray.
You keep bringing up old interesting ideas ,which I had forgotten about.
Some are even mine 😃
I do have a lot of DE , which we use for our chickens.
I might splash some on an eps chill box panel I am testing at the moment.
Not sure about the colour though 🤔
I will use the 50x50 mix to keep the weight down ,and see how it goes.
Steve.
You keep bringing up old interesting ideas ,which I had forgotten about.
Some are even mine 😃
I do have a lot of DE , which we use for our chickens.
I might splash some on an eps chill box panel I am testing at the moment.
Not sure about the colour though 🤔
I will use the 50x50 mix to keep the weight down ,and see how it goes.
Steve.
Moray.
The crate ply is a very flexible panel , in one direction only.
Although the rigidly in the other direction is not very rigid.
I presume this material is similar , maybe, to flexible ply ?
As I have said before, I like flexible light panels.
The sound of this panel is similar to my eps panels, but is still a little too heavy for that ultimate sound that I like.
And thanks for liking my recordings, much appreciated 👍
Steve.
The crate ply is a very flexible panel , in one direction only.
Although the rigidly in the other direction is not very rigid.
I presume this material is similar , maybe, to flexible ply ?
As I have said before, I like flexible light panels.
The sound of this panel is similar to my eps panels, but is still a little too heavy for that ultimate sound that I like.
And thanks for liking my recordings, much appreciated 👍
Steve.
Steve: I look forward to the results of our experiments. I had another thought about your comments on thicker EPS panels getting in the way of the high frequency energy emanating from the exciter. This may or may not be original but that's ok. Here are a couple of ways to make sure that the exciter energy is transferred evenly from the rear of a thick panel to the front. First one id to mark accurately on the back side of the panel exactly where the exciter mount is going to be, once done you would mark out lets say eight evenly spaced points on that circle where the VC former will sit, At these point you would insert penny nails (the kind with a flat head). To do this you would drill a hole the next size larger than the nail, then yu would insert some epoxy into the hole and then fit the nails into the hole. The nails should be long enough to reach as far as the front of the panel. This will provide a direct transmission line for the high frequency to penetrate the foam panel and should result in more high frequency being emitted on the front side of the panel, you might not require a tweeter hard to say.
The second way to do this is to use a hole saw which is the same diametre as the exciter VC. Once again the centre of the desired location needs to be marked on the back side of the panel. Once marked use the hole saw to drill out a plug from the panel. Carefully remove the plug from the hole saw and then with epoxy re -install the plug back into the panel. The saw has a kerf so the plug will be smaller than the hole by the thickness of the saw itself, this gap between the plug and the panel will be filled with epoxy which will turn into a hard cylinder which will serve the same purpose as the nails in the above suggestion.
This would be a good place to consider using add mixtures to your epoxy to harden it such as graphite powder or diatomaceous earth. Hope this is of interest.
The second way to do this is to use a hole saw which is the same diametre as the exciter VC. Once again the centre of the desired location needs to be marked on the back side of the panel. Once marked use the hole saw to drill out a plug from the panel. Carefully remove the plug from the hole saw and then with epoxy re -install the plug back into the panel. The saw has a kerf so the plug will be smaller than the hole by the thickness of the saw itself, this gap between the plug and the panel will be filled with epoxy which will turn into a hard cylinder which will serve the same purpose as the nails in the above suggestion.
This would be a good place to consider using add mixtures to your epoxy to harden it such as graphite powder or diatomaceous earth. Hope this is of interest.
using the same brace material but placing it horizontally rather than vertically (ie shorten the brace) will result is a stiffer brace with a resonant point much high up in frequency.
I am just guessing but I think that you could control the level of a whizzer via the degree of coupling it has to the panel. A hard coupling ought to translate into a higher energy transfer while decoupling the whizzer cone by using a softer coupling should decrease the energy transfer from the panel resulting in a more subdued level from the Whizzer. Does that seem reasonable?
suppose you could add a heat sink(s) to the back of the hot motors they don't have to weigh very much, or see if you can find locations which work as well but don't get as hot.
wow Steve that sounded excellent. So can you tell me what the spacing is between the film and the canvas and how you space the film (is it air tight))? How do you keep the film from rattling? kling film is a very generic description but generally they are a stretch type soft film have you tried any different films? I know from experience that stretch and shrink films are not reliable so far as long term stability go but for the moment that is not a concern.
do the exciters on these panels have ply supporters under them? These sound very good Stece these make me re-think other panels these are so simple to build.