What 1" CD with PR170M0 in a 3-way?

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I'm building a TMW 3-way with an Audax PR170M0 as the midrange.

I'm thinking of using a one-inch compression driver above it from say 2-2.5kHz.

I have a Faital Pro STH100 but may get a EOS-6 as well to compare.

However haven't decided on CD yet and looking for suggestions. So far I'm contemplating the likes of Beyma CD10Fe, FP HF100 or Celestion CDX1-1745 and Denovo DNA-360.

Any views?
 
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I own the Faital HF100's, they are inexpensive and as one would expect mate smoothly with their horn (that is, the exit / entry angles match), but it doesn't go very low, or really very high either. I've not heard the nicer Faitals, but they get expensive quickly.

When the B&C DE250 is around $100, I'd need a good reason to spend much more. The Denovo is very similar for less money. I don't know if the exit angle of those drivers matches (14 degrees I believe) that of the Faital horn, the EOS should be a good match for them though. The Celestion is supposed to be 20 degrees, so maybe not as smooth a match for the EOS if that matters to you.

Maybe http://www.diyaudio.com/forums/multi-way/277748-your-next-compression-driver.html is worth a try? No telling the angle, but the price and specs look good.

Happy hunting,

Bill
 
Blending the off-axis of the Audax PR170M0 will be difficult (without a waveguide of its own) - its "wide" dispersion extends to about 2.3 kHz and then "nose-dives" at a 60 degrees higher in freq.. To do it properly you'll need a steep high and low pass filter(s) right around that 2.2 to 2.4 kHz range with respect to the Faital Pro STH100.

The alternative with the same waveguide is to "flip" it and run it vertically with a nice low crossover freq. (below 1.5 kHz).

I'd be inclined to run *2* of the Faital Pro's vertically "back to back" as a dipole - with a bit of a rise targeted on-axis horizontally (..and listened to off-axis - horizontally). (..maybe a 3rd order Butterworth at 1.3 kHz as a "target".)

-and yes, I'd use the Peerless compression driver.
 
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JUST REVIEWING the PR170M0 datasheet:
~ 95db @ 2.83V (not 100db over normal frequency range)
Xmax = 0.5mm ==> limited SPL peaks below ~ 300-400Hz
Large SPL Resonances at > 3Khz
Polar response starts to widen ~2Khz

..... I can understand why there are several PR170M0 + Fountek NeoCD2.0 ribbon tweeter DIY designs. Ribbon tweeters deliver excellent detail, good dynamic, high efficiency, and vertical polar control that removes floor/ceiling early reflections. The NeoCD2.0 can supprt LR4 at 2.2-2.4Khz, ~95db @ 2.83V, extended >20Khz response, $85 seems acceptable.
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BUT... you would not be the only PR170M0 + horn tweeter design. I have the Faital HF10AK (Ketone Polymer)... detailed but not harsh. I use the HF10AK with the SEOS12 because it offers 90H x 40V polar which is ideal for home theater, and at 3.5" deep the SEOS physical time delay is a very close match to the TD10M. At $210 it is a long term investment which can be re-used with home Xovers as low at 900Hz. The HF108 datasheet also looks excellent, especially for a 2.2Khz Xover. NdFeB magnets + plastic dome is a winning formula. FOR THE VERY WEALTHY, the 18Sound NSD1095N with a TiNi diaphragm offers both bragging rights and very good reviews.

The STH100 80x70 Tractrix 3.4” deep looks like one of the best options for your PR170M0 design. The polar response should match well with the PR170M0 at 2.2Khz.
 

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One of the best drivers for the STH-100 Horn is the Celestion CDX1-1425/1430

The CDX1-1430 does look like a good choice for a 2.2Khz Xover...... it has a 1.4" diameter diaphragm

1" exit CDs are available with 1" 1.4" 1.7" 1.75" diameter diaphargms.
1" dome CDs recommend 2.5Khz+ Xover.

"All things being equal", a 1.4" diameter diaphragm should be the best choice for a 2.2Khz+ Xover. The CD exit angle should match the horn.

Celestion CDX1-1430 1.4" (35mm) diaphargm Al + mylar surround
B&C DE 120 1.4" (35mm) diaphargm Polyester diaphragm+ surround
18Sound ND1030 1.4" (34.4mm) Pure Titanium diaphragm + mylar surround

... 1.7"D diaphragms will allow future use with lower Xovers.
 
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JUST REVIEWING the PR170M0 datasheet:
~ 95db @ 2.83V (not 100db over normal frequency range)
Xmax = 0.5mm ==> limited SPL peaks below ~ 300-400Hz
Large SPL Resonances at > 3Khz
Polar response starts to widen ~2Khz

..... I can understand why there are several PR170M0 + Fountek NeoCD2.0 ribbon tweeter DIY designs. Ribbon tweeters deliver excellent detail, good dynamic, high efficiency, and vertical polar control that removes floor/ceiling early reflections. The NeoCD2.0 can supprt LR4 at 2.2-2.4Khz, ~95db @ 2.83V, extended >20Khz response, $85 seems acceptable.
===============
BUT... you would not be the only PR170M0 + horn tweeter design. I have the Faital HF10AK (Ketone Polymer)... detailed but not harsh. I use the HF10AK with the SEOS12 because it offers 90H x 40V polar which is ideal for home theater, and at 3.5" deep the SEOS physical time delay is a very close match to the TD10M. At $210 it is a long term investment which can be re-used with home Xovers as low at 900Hz. The HF108 datasheet also looks excellent, especially for a 2.2Khz Xover. NdFeB magnets + plastic dome is a winning formula. FOR THE VERY WEALTHY, the 18Sound NSD1095N with a TiNi diaphragm offers both bragging rights and very good reviews.

The STH100 80x70 Tractrix 3.4” deep looks like one of the best options for your PR170M0 design. The polar response should match well with the PR170M0 at 2.2Khz.

Hy LineSource, nice to meet You :)
I bought two pair of used hf10ak 16ohm (70 euro each pairs)

I want use these in a active crossovered two way professional system with ciare cw328


I have this amplifier for the mid & high frequency
McGrey PA4-750 DJ PA - Amplificatore 4 x 750 watt, nero: Amazon.it: Strumenti musicali e DJ
which despite the name is not all bad...

for the low frequency I use two pair of TL 15" woofer tuning at 37hz with carlsbro 2000

what type of horn I can use with this driver for professional use?

thanks a lot :)
 
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