FPS transducers - what to do with them?

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FPS planar drivers

I can be of some help with your FPS planar drivers. I work with FPS on the live-sound side and have some of the same FPS planar drivers in some little PipeLine speaker systems. FPS does not really provide tech. support (I'm an indep. contractor).

The FPS planar drivers' SPL is low and the bandwidth is limited, but they do sound good if EQd and used with woofers. If you want VHF "air" (extention) you may need to add a super-tweeter to ea. speaker system.

The model you bought is one of their smallest and they tend to use is as a tweeter or in mass as a line-array (for specs see http://www.fps-inc.co.jp/pl-spec.html).

I recently drew up a design concept (and bought materials) for DIY folks that would use very similar FPS planars (more square shape) as the MF drivers, along with small-cone mid-bass drivers and a BG Neo8PDR planar as the MH driver. This would be a very easy to build project as all the drivers are the same width, so the baffel is basicly two boards (with drivers lined up between).

Let me know what you had in mind with your FPS planar drivers and I will try to help.
 
Re: FPS planar drivers

ears4hire58 said:
I can be of some help with your FPS planar drivers. I work with FPS on the live-sound side and have some of the same FPS planar drivers in some little PipeLine speaker systems. FPS does not really provide tech. support (I'm an indep. contractor).

The FPS planar drivers' SPL is low and the bandwidth is limited, but they do sound good if EQd and used with woofers. If you want VHF "air" (extention) you may need to add a super-tweeter to ea. speaker system.

The model you bought is one of their smallest and they tend to use is as a tweeter or in mass as a line-array (for specs see http://www.fps-inc.co.jp/pl-spec.html).

I recently drew up a design concept (and bought materials) for DIY folks that would use very similar FPS planars (more square shape) as the MF drivers, along with small-cone mid-bass drivers and a BG Neo8PDR planar as the MH driver. This would be a very easy to build project as all the drivers are the same width, so the baffel is basicly two boards (with drivers lined up between).

Let me know what you had in mind with your FPS planar drivers and I will try to help.

Woot! Someone else who has heard of these!

You can see my horrible drawing of the speaker in the attached image. (Yay, msPaint!)

I was hoping to build a "bigger is better" horn-loaded speaker, but instead of using a full-range driver, I'd just use a mid-woofer instead, like one of the Silver Flute drivers. This would produce the necessary mid-bass for these panels. A ribbon tweeter (ApexJr $5 model) would be used as a "helper tweeter".

You can see specs on the "Bigger is Better" here:
http://www.zillaspeak.com/bib-howtobuild.asp
http://www.zillaspeak.com/bib.asp

As you can see, most variants work well from about 40 hz up to about 100hz, and then start to roll off.
 

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The curves for the "bigger is better" horn-loaded speaker look rather rough (vary 15 dB).

It would be better to have at least two spaced woofers (>1 on ea. end) or better yet a line source of woofers to come close to matching the directivity of the ribbon/planar line source.

It is not a good idea to break the HF driver line, as that will create an uneven polar response.

I have attached a jpg file including the basics of a similar tower-shaped speaker concept I am working on; it includes a BG NEO8PDR to add some MF & lots of HF (higher SPL than the FPSs) but the BG does have a HF peak on axis (& several small woofers for mid-bass).

If higher SPL is not needed, I would just insert a nice little ribbon/planar tweeter (like the Foster) in the middle of the four FPS ribbon/planar line source.
 

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Daveis said:
Ears,

How did you get your hands on some samples? Are they expensive?

Had a chance to compare those FPS1030(M3F1R1) to any of the BG's drivers (Neo or RD series)?


I do contract consulting and marketing work for some of these planar driver companies (mostly in the concert/PA market).

The samples are in a few locations right now. I should have them all in the same room to compare by month end (for some trade shows in Jan.).

The little FPS planars (like 3x4 image @ left) are cheap, <$25 in qty.

The FPS1030 (6x14") are about $400 depending on vintage and qty. The FPS2030 (11x14") are about $700 depending on vintage and qty.

The attached pic. is of several of the FPS1030 and FPS2030 planar drivers in a large concert application (subs not shown). The larger FPS2030 planar drivers have a Fs of 90Hz and handle 125W long term.

Do you guys think that I should work out some way to make these (and other hard to find planar drivers) available to the DIY group?

Do you guys have some applications in mind or should I set up a web site with some design ideas for these and other planar drivers (or both)?
 

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ears4hire58 said:



I do contract consulting and marketing work for some of these planar driver companies (mostly in the concert/PA market).

The samples are in a few locations right now. I should have them all in the same room to compare by month end (for some trade shows in Jan.).

The little FPS planars (like 3x4 image @ left) are cheap, <$25 in qty.

The FPS1030 (6x14") are about $400 depending on vintage and qty. The FPS2030 (11x14") are about $700 depending on vintage and qty.

The attached pic. is of several of the FPS1030 and FPS2030 planar drivers in a large concert application (subs not shown). The larger FPS2030 planar drivers have a Fs of 90Hz and handle 125W long term.

Do you guys think that I should work out some way to make these (and other hard to find planar drivers) available to the DIY group?

Do you guys have some applications in mind or should I set up a web site with some design ideas for these and other planar drivers (or both)?


I paid $10 ea. for mine - not too much, I guess.

Any suggestions for a use for them? I have eight, and would like to try building a pair of decent speakers from them.
 
ears4hire58 said:


With 4 of the little 2x12 FPS panels you can make the = of this little line-array: http://www.fps-inc.co.jp/s_images/english_specseat/en_spec_pl4_0212.pdf

They do need a little EQ to flatten out.

I think that the picture is missing from the PDF, but I get the idea regardless - I'd just use four, one on top of the other, for a 2x96 cell array?

Also, here's a nice option for a tweeter:

Alternative ribbon driver link

It's cheap, and performs pretty well. It also has a similar SPL at the same voltage, similar impeadance, and more. Wiring it in parallel with the panels using a small capacitor to cross it in at roughly 15khz should help with the treble.

For the woofer, I was thinking of using a nice, cheap Silver Flute 8" unit - $30-$40 each, and they work nicely down to 40hz, making the use of a subwoofer optional. This would be in a ported box, with the line array placed on top of it.

I'm going for sound quality and low distortion here, and not simple output power. Do you think that the FPS units are capable of meeting my requirements?
 
I just found the freq. response curve for the little FPS0212 (ribbon shapped) planar driver (shown Left) and gave them a quick listen in the FPS 200 2.1 PC system. They actually have good HF as a single driver, rolling off very slowly, -3dB @ 20k. They have a 3dB bump @ the 5kHz. octave.

But in a line-array config. (of approx. 4 planars) the mid-bass bump (+6dB 150-400Hz.) will be more pronounced. So dropping the mid-bass bump could be more of an issue than adding a tweeter. They have a low end cut-off @ 150Hz. I hope that this added info. helps.
 
ears4hire58 said:
I just found the freq. response curve for the little FPS0212 (ribbon shapped) planar driver (shown Left) and gave them a quick listen in the FPS 200 2.1 PC system. They actually have good HF as a single driver, rolling off very slowly, -3dB @ 20k. They have a 3dB bump @ the 5kHz. octave.

But in a line-array config. (of approx. 4 planars) the mid-bass bump (+6dB 150-400Hz.) will be more pronounced. So dropping the mid-bass bump could be more of an issue than adding a tweeter. They have a low end cut-off @ 150Hz. I hope that this added info. helps.

Very interesting.

I'm a bit new to line arrays, and very new to FPS panels - what sort of (open?) baffle should I mount them in? Series/parallel wiring is the obvious choice, but I don't know any more than that.

Also, do you know if the PC system drivers have an active EQ? I would be bi-amping these speakers (likely with a LM3386 per channel or 4-channel Class D amp), so a filter or two would not be any trouble, and should make it easier to integrate the woofer.

At what frequency would you reccomend crossing these over to the woofer? 250hz is pretty common.

Also, do you think that the Silver Flute woofer in a seperate ported box (as per the Madisound website's specs) would work well for bass? These drivers have been used as subwoofers before with good results, and for home-theater, I think they would make a nice choice. And, at $65 a pair, I can actually afford them. (I live very, very near madisound.)
 
Spasticteapot said:


Very interesting.

I'm a bit new to line arrays, and very new to FPS panels - what sort of (open?) baffle should I mount them in? Series/parallel wiring is the obvious choice, but I don't know any more than that.

Also, do you know if the PC system drivers have an active EQ? I would be bi-amping these speakers (likely with a LM3386 per channel or 4-channel Class D amp), so a filter or two would not be any trouble, and should make it easier to integrate the woofer.

At what frequency would you reccomend crossing these over to the woofer? 250hz is pretty common.

Also, do you think that the Silver Flute woofer in a seperate ported box (as per the Madisound website's specs) would work well for bass? These drivers have been used as subwoofers before with good results, and for home-theater, I think they would make a nice choice. And, at $65 a pair, I can actually afford them. (I live very, very near madisound.)

Baffle them basicly like the drawing in my Post #4 above.

I don't know if the PC system drivers have active EQ. Contact FPS USA (http://www.usfps.com/contact.html) for the PipeLine application guide; it has the EQ data you need.

Your XO sounds good, but porting is not the most hi-fi way to load a woofer; read the dipole and sealed box topics here.
 
ears4hire58 said:


Baffle them basicly like the drawing in my Post #4 above.

I don't know if the PC system drivers have active EQ. Contact FPS USA (http://www.usfps.com/contact.html) for the PipeLine application guide; it has the EQ data you need.

Your XO sounds good, but porting is not the most hi-fi way to load a woofer; read the dipole and sealed box topics here.



I'll see if they can give me a hand - thanks for the link.

Although a sealed box is tempting, I don't know if it's worth the loss in efficiency and low-end bass performance. The same applies to dipoles - they also have the side disadvantage of doubling the number of required drivers.
 
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