FF85wk reaches up to something like 25k, it makes a really decent tweeter. Not so much the FE83.
At the low end, at limited volume you can squeeze 85-90 Hz out of the FF85wk. The FE83 has almost an octave less reach. These differences are reflected in the efficiency.
At fiyFEST the FF85wk did well with a 1st order at 160 Hz. To plump up the midbass (and allow for an attempt at a passive XO) i'm gonna try 240 Hz next
dave
At the low end, at limited volume you can squeeze 85-90 Hz out of the FF85wk. The FE83 has almost an octave less reach. These differences are reflected in the efficiency.
At fiyFEST the FF85wk did well with a 1st order at 160 Hz. To plump up the midbass (and allow for an attempt at a passive XO) i'm gonna try 240 Hz next
dave
-Depends what you mean by 'excel'
-That depends on what slopes you're planning on using, what other drivers you are planning on using, the baffle dimensions and shape, and your requirements for the resulting end system. It's not quite as simple as just picking X frequency & using that for whatever order slope you want, since the changing impedance of the driver becomes, or may become, a significant factor, particularly with low order slopes.
-Yes, they've both got useful output to 20KHz on-axis and measure well, especially the 85, which is good for > 20KHz.
-Depends on what your requirements are in terms of HF dispersion. Both are good as wideband units go, but if you need considerable off-axis capability, they're not going to match a quality 3/4in dome or similar.
-That depends on what slopes you're planning on using, what other drivers you are planning on using, the baffle dimensions and shape, and your requirements for the resulting end system. It's not quite as simple as just picking X frequency & using that for whatever order slope you want, since the changing impedance of the driver becomes, or may become, a significant factor, particularly with low order slopes.
-Yes, they've both got useful output to 20KHz on-axis and measure well, especially the 85, which is good for > 20KHz.
-Depends on what your requirements are in terms of HF dispersion. Both are good as wideband units go, but if you need considerable off-axis capability, they're not going to match a quality 3/4in dome or similar.
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With the 3/4" dustcaps on these they aren't as far behind the tweeter as you may think.
BTW: how is Colin doing on yours?
dave
Hmm, based on published specs it's not suitable for a BLH except of the Voigt pipe variety such as the BIB.
GM
I have a vague recollection of inquiring about it a while ago. (Maybe it was one of my first messages actually. At that point, I was still considering the look of the driver as well.)
Well, then it might be a suitable candidate to pair with subwoofers. (I'm still considering that in the back of my brain because I thought about using 5-1/4 inch mid-bass with tweeters but I keep on thinking in a desktop cabinet, I might not have as much bass as say, 8 inch woofers in cabinets on the floor. Whatever, I'm still undecided even though I think woofer + tweeter might be superior overall.)
Based on published specs, 3.65 L sealed yields a Qtc = Qts and doesn't exceed Xmax at rated power, so no XO needed to mate to a woofer..........
GM
low end i will be covering with a woofer (model not decided yet) which can go upto 500hz flat. so there wont be stress on the ff85wk below 500hz. please suggest an optimum xover point to begin with.
how about going OB for ff85wk?
any other full range drivers in the same budget and size?
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Woofer only reaches to 500 Hz? Our 1st successes had the XO 330-350 Hz, in one case the woofer reached 1.4k, in the other 3.5k. The one we are working on now has woofers that get upnear 5k.
The woofer needs to have capability beyond the XO, a couple octaves is nice. If your woof only goes that high i'd suggest 200-250 as a starting point.
dave
woofer can reach well beyond 500hz. but at the minimum 500hz it will reach is what i meant. if i am going for a 6.5" woofer then i can expect it to reach 2k min. in case of 8" it may reach upto 1.5k. but would like to cross over to the full ranger as low as possible. planning to drive the ff85wk with T-amp initially to keep budget and complexity low.
I recently did an MTM with the FE83en. I crossed at 450hz to a pair of silver flute 6.5" 8ohm woofers in parallel. You an see the attached outdoor measurements. It's a 2nd order Linkwitz Riley. I measured the null and it's pretty wide / uniform / deep. The impedance is smooth. But there is a hiccup at 2khz that is related to the FE83en. Also the high frequencies aren't as in balance as the low end of the speaker. The high frequencies are also a tad beamy, audible and measurably. That's if you're comparing it to a 3/4" dome tweeter.
I built this to mate with a subwoofer and offer fairly high output as a centre channel in someones HT. So I crossed higher than needed really. This kept the xo cheaper too though. Getting power handling out of the FE83en doesn't come without crossing high imo. Like Dave said, the FF85 would likley cross lower. But then there's effeciency. Any lower than 500hz isn't really doing all that much good. I measured the off axis and it was quite uniform. And this speaker measured about 90db/2.83V/m with ample BSC. (yes I'm aware most centre channels don't need baffle step compensation, I did it because the receiver's auddesay gets to take it out. Putting it in with the receiver is hard to do.)
I built this to mate with a subwoofer and offer fairly high output as a centre channel in someones HT. So I crossed higher than needed really. This kept the xo cheaper too though. Getting power handling out of the FE83en doesn't come without crossing high imo. Like Dave said, the FF85 would likley cross lower. But then there's effeciency. Any lower than 500hz isn't really doing all that much good. I measured the off axis and it was quite uniform. And this speaker measured about 90db/2.83V/m with ample BSC. (yes I'm aware most centre channels don't need baffle step compensation, I did it because the receiver's auddesay gets to take it out. Putting it in with the receiver is hard to do.)
Attachments
If you have a spare amp, much cheaper to PLLXO, here are the parts for a 1st pass at a 240 Hz passive for FF85, 2xPeerless 830870'
dave
Attachments
Yes that's true. Pretty much any xo less than 500hz it's cheaper to go active. But for this person, active didn't make sense. For the OP though, I'd say Dave is right on.
We are working on the passive XO for those kind of people. The uFonkenSET + woofT is something special. And we are working on a followup desire that is monolithic and inspired by the blade. Wherever i end up with the Passive XO, this next one will need a choke 2x as large.
dave
PS: Ryan, Speaking of XOs.... i have some waveguide boxes that are quietly waiting for an XO upgrade
dave
PS: Ryan, Speaking of XOs.... i have some waveguide boxes that are quietly waiting for an XO upgrade
PS: Ryan, Speaking of XOs.... i have some waveguide boxes that are quietly waiting for an XO upgrade
Ya, I know, sorry. And I have your Alp10BW horns sitting here. You wouldn't believe how many times I have been "supposed" to go to Victoria and plans change at the last minute
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