Will magnet grill guides affect the esl?

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Hello all,
I bought some 3/8" dia magnets from Parts Express to hold the grills on the hybrid esl's I'm building. These little magnets are incredibly powerful (their pull can be felt several inches away)-- so powerful in fact that I'm wondering if having them within an inch of my ESL panels will affect performance or possibly even create an arc path.

Has anyone here used magnetic grill guides in close proximity to esl panels?

Charlie
 
Probably not/maybe...

the straight answer is that you will really have to expetiment both with and without to know for sure. I can say that I have been able to hear the difference between magnetic steel screws and non magnetic SS screws and nylon screws to mount the panels so you can see my reason for possible concern. I don''t see you feeling that they sound bad using the magnet mounts for the grill just a case of perhaps nicer with out. There is a way to significantly reduce the impact of those magnets. Use the metal cups that are available for the flat clyndrical neo magnets. This will redirect magnet flux around the magnet and concentrate it into a very small gap. This is the same principal used in a shielding can around a dynamic loudspeaker magnet.
Tell us some more about your esl's. Are they perf metal or insulated wire stators? Got any pictures to show us? Thanks if you post any pics.
 
I will try to incorporate a metal ring around the magnets (sounds like a great idea). I have the design finalized for my esl's and I have a Delta-cad drawing but no pics as yet. I just started cutting MDF board yesterday. The stators will be .063 perf steel 12x48 with a woofer below-- I ordered and paid for 100:1 trannys and power supplies from Just Real Music back in February and there has been one delay after another and I still don't have them (getting quite concerned about it).
The design is kinda unlike anything I've seen--- not sure how it will sound but it's pretty radical:
I have a 10" Aurum Cantus MkII woofer on the bottom, canted 6 degrees up in a 9-ft transmission line cabinet with the ESL panel mounted over the woofer. The box has a footprint only 15" x 21.5" but it's 5 1/2 feet high behind the ESL panel--- the front edge of the box behind the esl is a "V" shaped beam splitter. I will make some pics available as I progress with the build.
I can send you the drawing if you have Delta-cad.

thanks again for the tip on the magnet shielding!

Charlie
 
magnet cups....

here is a link to the kind of magnet cups I was talking about. Sounds like you will have a really interesting and visually attractive set of hybrid speakers. I don't have the program necessary so will look forward to seeing pictures when they arrive. Don't worry about Russ he is a good man he won't let you down.

http://www.eamagnetics.com/info_magnetic_assemblies.asp
 
CharlieM said:
I ordered and paid for 100:1 trannys and power supplies from Just Real Music back in February and there has been one delay after another and I still don't have them (getting quite concerned about it).

You will eventually get what you ordered but it will take a while and try your patience. Took me 7 months to get a set of panels I paid for instantly. Search the forums for "Just Real Music" for others similar experiences and what worked to speed up the process. I had to threaten legal action to get my order shipped.
 
Back to the original question---whether magnetic fields will cause problems---I'm in agreement with GlidingDutchman. I'd be at a loss when trying to come up with a mechanism through which the sort of magnetic fields you're talking about could have an audible effect on an ESL. That's not the same as saying it's impossible, but I think the risk is so low that I wouldn't hesitate to use the magnets, with or without "shielding cups."
Few
 
thanks Y'all !

This has turned out to be quite an interesting discussion and I certainly don't know the answer. The magnets will be installed from the backside in the baffleboard during fabrication so as to place them just below the exterior surface (invisible). Since the magnets will then be inaccessible and I can't be sure of no adverse effects, I'm gonna sheild the magnets with metal cups, as Moray suggested. Better to err on the safe side, eh?

Since I mentioned my experience with Just Real Music earlier in the thread (not sure if that was appropriate or not), in fairness let me now say that I've just received assurances that my order will ship late next week. I should also say that Russ was very helpful in answering my many questions and I got a fair price on the order. I sincerly hope I will have cause to post more positive comments about Just Real Music in the near future.

I will post pics or links for my esl project soon.
thanks all!

Charlie
 
I finally got the transformers and bias power supplies but still waiting on the perforated metal and diaphram coating solution. It's been very frustrating trying to get the components since mid-February and it's not over yet. So, I havent had the opportunity to try out the magnets but they are already mounted in one of the speaker boxes; which is nearing completion. I still have a long way to go on the other one-- adding the 1/4 plywood covering and edge trim over the MDF is very tedious and time-consuming.

It's a pretty radical disign, what with the 10" Aurum Cantus woofer in a compact 9ft TL, having only a 15" x 21.5" footprint. The cabinet goes up (63" high) rather than back so it's forward surface had to be a "V" shaped beam splitter behind the ESL. This seemed the only feasible way to place the woofer under the esl panel in such a large cabinet volume without a huge footprint and it also allows placing the speaker close to the wall. I have pics but can't figure out how to upload them here at any decent resolution. The boxes arent finished but I can email you some pics if you'd like to see them.
Charlie
 
Grill Magnets Did Not Affect My ESL

Hello all,

It's about time I updated this old posting:
I finished my hybrid ESL speaker project months ago and I did use the 3/8 diameter neodymium grill magnets from Parts Express. The magnets are inside (just under the surface) of the wood frame about 3/4" from the stators. I was concerned (and convinced) that the grill magnets would have some bad effect but I am happy to report I can't detect any audible effects from the magnets. I've even removed the grill while the speaker was playing and allowed the [magnet] corner of the grill to touch the center area of the front stator with no apparent effect... no arcing, no change in the sound; nothing.

Have a great day all !
click links below to see my speakers

http://img357.imageshack.us/my.php?image=myesl022ef1.jpg
http://img381.imageshack.us/my.php?image=eslgrills005ny0.jpg
 
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