Is it possible to cover the whole spectrum, high SPL, low distortion with a 2-way?

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Now I don’t want you guys to stop discussing the synergy design. Do not continue to discuss synergy all the while skipping over questions I’ve posted in my own thread, if you can post about what now is a side topic please at least lend me a hand on my quest.
 
What I’m most concerned about is exit size, I’m starting to think that 2” is not the product for the job, considering 700hz isn’t that low of a crossover and that 1.4 will have a better top end. Is this correct thinking?

I’ll check out your link and ty for taking the time
 
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What I’m most concerned about is exit size, I’m starting to think that 2” is not the product for the job, considering 700hz isn’t that low of a crossover and that 1.4 will have a better top end. Is this correct thinking?

I’ll check out your link and ty for taking the time


The exit is just one aspect of a compression driver.
Before jumping to conclusions, it makes sense to dive a little deeper into the inards and compare drivers.
Faital-Pro for instance, offers several 1.4" (exit) drivers, some with a 65mm diaphragm and some with 74mm diaphragm. The latter versions will allow a lower XO.

Besides, some drivers with a larger diaphragm outperform smaller diaphragm drivers, even at the top end. This could be attributed to many aspects, but most likely: magnet structure, differences in the design of the phase-plug, the diaphragm material, the suspension of the diaphragm.

One example is the RCF mentioned previously. Contrary to what one would expect, the 2" exit version appears to outperform the 1.4".

Finally, the horn used can make a big difference. As a rule of thumb: you want to match the exit angle, but more importantly: the flare rate of the (conical) exit section of the driver to the throat section of the horn. A 'pancake style' driver with the phase-plug close to the exit and a larger exit angle is a better match to a waveguide (rapid expansion rate at the apex), whereas a driver with a longer conical exit (phase plug further back from the exit) and a smaller exit angle often work better with more traditional horns. Those are longer horns with a low flare rate at the apex> Exponential, Tractrix, Spherical etc.
 
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What about the Faital Pro 18FH500, reasonable price, seems very smooth. Might work with xo at 800hz.
RCF L18P300 also seems ok, a bit lower sensitivity.

The Faital Pro 18HP1030 almost seems like having incorporated BSC, looks nice.
Beyma 18PWB1000Fe might be something to look at.
Precision Devices PD.186/2
... Fane Colossus 18SB (?)
 
Well the first post that went in this direction, to have a little clarity to my inquisition, it’s buried behind other post about synergies
951 vs 950 radians
Both have the same internals, only difference is exit size, the model with a 1.4 exit seems to have a smoother response than the one with a 2” exit. If the difference between the two is extension in one direction or the other then I’d likely go for the 1.4” version
 
Yeah, I just thought you had a nice bunch of good compression drivers to look at now, so maybe it's easier to choose "the right one" after looking at some woofers within the desired budget.

I've been thinking myself as well, that a good CD + 18" might be a good solution, so definitely interested in what will happen here.
Synergy designs are intriguing and all that, but not something I can imagine living with long term.
Aiming in the general direction of stable long term, good stuff, huge amount of quality listening experiences, not so much fiddling about. If that makes any sense.

Edit:
And what kind of horns are you looking at?
 
I think if I settle on the Radian 951 I won't be disappointed
The RCF HF99 90x90 looks to be a wise choice...Though I kinda had my hopes set on a 90 x 40, The RCf HF94 90x40 has a strange shape in the throat.

My last choice for an 18" was For an 18" I'm really digging the SAF184.01
http://www.lavocespeakers.com/lavoc...87263_LAVOCE_SAF184.01_18in_SUBWOOFER_A.a.pdf
Good in many aspects. The AE 18" speakers wants a crazy box size (160 cubic ft or so) though is a better driver. The Lavoce is better than more than a few 18's and ask's for a ~3ft3 box.


GM maybe you are thinking something like the FaitalPRO 18FH500 16Ω? The lavoce claims a range to 1500hz, I'm aiming for low pass no higher than 700hz.
 
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AE TD18 would be the best and works in 4ft. cubed and up.

FaitalPRO 18FH500 has been used successfully over 1khz in some designs. Good option as well.

As mentioned earlier in the thread, 18 Sound XT1464 is a very nice horn and one of the best you can easily buy. Narrow dispersion, but has optimized contours, nice polars, and rave subjective reviews over just about any horn/waveguide in its class.

You'll need measurement equipment and some form of EQ to get the best out of any speaker. DSP crossovers are your friend.
 
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See the sketch of the xt1464 below. In the middle drawing it appears that there is a constriction in the throat? Am I looking at that right? After all the work I went to to match the compression driver exit angle with the horn throat angle, such a constriction seems like a terrible thing. Hopefully I'm misunderstanding something.


Edit: otherwise seems like it measures great. It's long enough to give adequate output on the high end to still use SET amp, and seems to extend down to 500hz usable with some cd's and a little eq.
 

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See the sketch of the xt1464 below. In the middle drawing it appears that there is a constriction in the throat? Am I looking at that right? After all the work I went to to match the compression driver exit angle with the horn throat angle, such a constriction seems like a terrible thing. Hopefully I'm misunderstanding something.


Edit: otherwise seems like it measures great. It's long enough to give adequate output on the high end to still use SET amp, and seems to extend down to 500hz usable with some cd's and a little eq.

Almost appears to be a hidden dispersion slot.

No number of small enhancements eliminates the relatively severe time-domain distortions inherent to the application of a diffraction slot to achieve high VHF dispersion."
- Ro808

Also...I must say.. I can't tell which is better the Radian 951 or 950...its kinda look likes its the 950....but the 951 cost more...maybe that dip at 14k is a sign of break up.
 
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See the sketch of the xt1464 below. In the middle drawing it appears that there is a constriction in the throat? Am I looking at that right? After all the work I went to to match the compression driver exit angle with the horn throat angle, such a constriction seems like a terrible thing. Hopefully I'm misunderstanding something.


Edit: otherwise seems like it measures great. It's long enough to give adequate output on the high end to still use SET amp, and seems to extend down to 500hz usable with some cd's and a little eq.

This was discussed a few months ago. It's not what it looks like. In hand reports show no constriction in the throat.
 
Test Bench: The 951PB 1.4" Compression Driver from Radian Audio Engineering | audioXpress

Just when you thought you knew a driver....this graph does not look as pretty as the one on the Radian website. *Facepalm* maybe its the horn...Radian does specify they used a horn with a wider angle 120 x 40 be exact. TO bad they didn't have enough sense to specify the actual brand/model...I'll call them I guess.

All 4" non-beryllium diaphragms look rough above 10khz(though that RCF looks pretty good considering). If you want the best, save up for the Be version and call it a day.

Those plots are also misleading as well since the drivers aren't EQ'd flat before measuring. The 950 graphs show a huge dip in the upper octave frequency response curves. This will look better in the waterfall plots of course.
 

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