# The Plasmoid Project - How close to the TV can they go?



## seattle_ice (Jul 12, 2006)

*The Plasmoid Project - Close to the TV and far from the pocketbook*

I have a need to build somewhere between 5-7 pairs of a certain type of speaker. I am no expert, by any means, but with some help, I do have some experience, some decent measurement capabilities, and the willingness to work at it until it is done.

What I am trying to come up with are some inexpensive narrow floorstanding MTM's designed to be placed with the baffle around 18-20" but no more than 24" from the back wall and within 12" or so from each side of a large projection TV or plasma/LCD on a furniture stand.

This all started when I noticed that my brother, my parents and a number of my friends all subscribe to the $100 pioneer/alpine/etc. floorstanders next to the big screen tv theory (except my sister, but she has NO speakers). They all sound terribly muffled, hard to hear dialogue on, and just not very good.

So for Christmas presents, maybe next year, since it will take some time to construct a bunch of identical pairs of speakers, I will make all these to work in that specific environment.

For the drivers, I am considering the MCM-55-3870 5.5" woofer wired in parallel with a North D25-6 tweeter, crossed over ~1900hz or so.

The MCM just seems to look really good on paper (to my untrained eye) for the price.



















And the same goes for the North D25-6. At $18 a pop, this works in to the plan quite well. 










If along the way I miss anything (and I will), everyone feel free to point it out.

The cabinets will be somewhere along the lines of 25-30L, probably ported. 36" high cabinets on 3-4" pedestals with a 8" wide baffle with a 1" roundover and about a foot deep.


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## Anthony (Oct 5, 2006)

For plasma/lcd, don't worry about unshielded being too close to the TV.

For CRT, it all depends on the magnet. I had a sony 27" CRT a decade ago that was 2 feet above an unshielded subwoofer and was just fine. Any closer and you got weird green lines everywhere. 

That was a pretty big magnet, though. Hope this helps some.


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## tonyvdb (Sep 5, 2007)

Generally if you stay 2' away from a CRT with unshielded speakers you will be fine, any closer and you run the risk of causing permanent damage over time.


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## seattle_ice (Jul 12, 2006)

Guys, thanks, but the 'How close can they go?' was a rhetorical utterance in search of a little humor. Still searching I see.

Here is my model in Unibox - 26L enclosure, 2.5" x 7" flared port, walls covered with damping. Looks pretty good for a pair of 5.5" drivers that cost so little.

Fb = 40hz, F3 34.67 hz. I am planning on a baffle that measures 7.5" x 36" or so.










I ordered a pair of these woofers, and will mock up a speaker box when I get them to measure them and the tweeter.


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