FPS Planar speakers

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Hi,
has anybody experience with these FPS planar drivers (FPS C0104MN10VIII Mono) See also
FPS C0104MN10VIII Mono 1/2" x 7-1/2" Planar Speaker 8 Ohm 20W

Since I'm working on an open baffle line array prototype, this could be an affordable arrayed tweeter alternative (to my dream of multiple Mundorf AMT dipoles..)
It's not reaching further than 15k, but could maybe work if the sound quality is good? Or is it just made for TV's and computers..?
 
You mention the limited upper frequency limitation of these drivers. Let me raise other considerations with the FPS drivers that converge to impact the dynamic range of these units. The stated specification for 1 watt SPL is 83 db but at a distance of 0.5 meter vs. the usual 1 meter. Thus the 1 meter at 1 watt SPL is 6 dB lower (assuming far field radiating following a 6 dB per doubling of distance roll-off). That means you are dealing with a 77 dB SPL driver at 1 meter for comparison to other drivers.

This low sensitivity is compounded by the 10 watts power rating (20 watts max) so if you apply 10 watts power to these drivers, the output SPL level is typically no more than 87 dB. This is a driver without much dynamic range.

Now you could a vertically array these drivers to create a near field within your room so that the sound roll-off is 3 dB per doubling of distance but you still have a low sensitivity driver. Arraying units horizontally (still vertical inclined but spaced side by side) would increase output levels but spacing would have to be very close.

My comment is that while a physically attractive line array driver, significant limitations abound.
 
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Thanks for that input Jim. They claim that the drivers output is like a LED:
"This ideal planar wave output focuses sound into a highly direction beam, similar to the output of an LED light. Which differs from the diffuse output (SPL) of convention speakers, which is similar to an incandescent light. Not only does this decrease the loss of output over distance, it also presents the listener with more coherent sound."
Saw somewhere that this would compare more to the 3dB loss of an array than the usual 6dB for a single cone.
The array I'm bulding is going to be active - but maybe it's limited anyway?
 
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You are ultimately limited by the SPL at the power handling of your drivers. If these are for a small to moderate sized room and you listen at reasonable levels, then these drivers will give you joy.

I assume that you have a plan to add super tweeters to cover the above 15 khz portion of band. Perhaps a single pair of those Mundorfs AMT tweets can easily fill that shortcoming. I'm thinking a MTM arrangement with the FPS drivers acting as the M's while a set of Mundorfs (or your choice) playing the role of the T. A tall, slim array with a set of open baffle or H-frame woofers to cover the bottom of the band.


Jim
 
The array I'm building/experimenting with is based on 16 Vifa TC9FD each seen here:
http://www.diyaudio.com/forums/multi-way/261375-open-baffle-dipole-line-array-prototype.html
Original thought about these FPS drivers were to make a cheap tweeter array, but I guess using a single AMT will still be a better solution. Problem is the difference i line heights since the Vifas must be xo at 3-4kHz. Maybe building a long (dipole) ribbon tweeter is a better option in this case?
 
Thanks for that input Jim. They claim that the drivers output is like a LED:
"This ideal planar wave output focuses sound into a highly direction beam, similar to the output of an LED light. Which differs from the diffuse output (SPL) of convention speakers, which is similar to an incandescent light. Not only does this decrease the loss of output over distance, it also presents the listener with more coherent sound."
Saw somewhere that this would compare more to the 3dB loss of an array than the usual 6dB for a single cone.
The array I'm bulding is going to be active - but maybe it's limited anyway?

Aren't highly directional, beamy tweeters sort of, you know, a bad thing?

I'm a guy who loves oddball transducers but this one, eh, does not excite me.
 
ericj,

Tall vertically stacked arrays of planar or ribbon drivers are very useful in line arrays as they do exhibit wide horizontal dispersion and even vertical dispersion over their vertical dimension.

Directional or 'beamy' tweeters can serve a useful purpose in many situations. One example is that planar or ribbon drivers will alleviate floor and ceiling reflections for some listening rooms.

Finally, if you avoid the use of directional drivers, then public address systems would be very limited. PA systems are all about radiating their energy toward the audience and minimal sound elsewhere.

Likewise you can design speakers for your living room that have the same attributes. Thus, you could minimize the effects of walls, floor and ceiling in your room. Directional speakers can be a very good solution for sonic issues.

Jim
 
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