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Discussion Starter #1
Has anyone ever seen actual measurements of this coax other than the manufacturers plots? Even ignoring the 10db scale, the tweeter measurements are much smoother than you normally see for a coax with a compression driver.
 

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What chart are you looking at? That on the data sheet is nothing special.
 

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Bill, I was comparing to it the tweeter response above 4k of other coaxes like the B&C 8cxt or 8cxn51. The Faital has a wide peak from 1.5-8k but then is smoother above that where as the others have a narrower peak from 1.5- 4k but then a number of 5-7db peaks above that.
 

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Quote:
Originally Posted by djarchow  /t/1474221/faital-pro-8hx200-measurements#post_23354885


Bill, I was comparing to it the tweeter response above 4k of other coaxes like the B&C 8cxt or 8cxn51. The Faital has a wide peak from 1.5-8k but then is smoother above that where as the others have a narrower peak from 1.5- 4k but then a number of 5-7db peaks above that.
They're not all that different. The spikes on the B&C chart may indicate less smoothing.
 

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Quote:
Originally Posted by Bill Fitzmaurice  /t/1474221/faital-pro-8hx200-measurements#post_23355222


They're not all that different. The spikes on the B&C chart may indicate less smoothing.

I would like to know, have you ever heard any coaxials which approach the performance of separates of the same size? I was just viewing the specs on the same coaxial (faital pro 8hx200), and yes, the curve looks smooth but misleading. I am interested in knowing of any experience you may have listening and measuring coaxials--are there any coaxials which do not suffer from the common ragged upper frequency response (excluding TANNOY--the drivers would have to be obtainable for me, like the aforementioned model). I appreciate any advice you can offer.
 

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Quote:
Originally Posted by djarchow  /t/1474221/faital-pro-8hx200-measurements#post_24355212


Here are the measurements of the Faital in my cabinet along with the AE TD10X


I did not realise someone had responded.


I assume the other colored lines are 30 degrees and 45 degrees off-axis? If so, is 30 degrees off-axis considerable (-3dB or more), or not considerable? In either case, the response does not exhibit the horrid peaks I have observed in other coaxial plots. I presume they are simply not there or negligible, yes? Is coloration dicernable?


Thank you for the info. I am trying to determine if purchasing a few will be necessary for an experimental loudspeaker, or if I should pass (absent testing).
 

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Quote:
Originally Posted by djarchow  /t/1474221/faital-pro-8hx200-measurements#post_24355212


Here are the measurements of the Faital in my cabinet along with the AE TD10X


I just noticed the note at the bottom of the graph, which shows these are not on-axis and the common off-axis permutations. Nonetheless, your on line measurements match the published response curves almost identically, so at least that helps verify the on-axis. I will try to find a cut-away view of the driver to decide if risking a purchase to do off-axis response will be a worthy venture.


My main concern is coloration and off-axis response output decline at 30 degrees.


Nonetheless, thank you for the data.
 

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Quote:
Originally Posted by Ivan Azymov  /t/1474221/faital-pro-8hx200-measurements/0_60#post_24355044


I would like to know, have you ever heard any coaxials which approach the performance of separates of the same size? I was just viewing the specs on the same coaxial (faital pro 8hx200), and yes, the curve looks smooth but misleading. I am interested in knowing of any experience you may have listening and measuring coaxials--are there any coaxials which do not suffer from the common ragged upper frequency response (excluding TANNOY--the drivers would have to be obtainable for me, like the aforementioned model). I appreciate any advice you can offer.

Basically no, the HF response of pro coaxes will all be ragged in the upper frequencies because of how the HF CD mates to the throat of the coax driver. The pro driver manufacturers basically all use similar designs for these coax's where the CD transitions into the cone and it is always a compromise that negatively affects HF response. In pro use it is generally not a problem and speakers like the Seaton Cat's and JTR Triple have shown that it is not a deal breaker in Hifi and HT use.
 

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Discussion Starter #10

Quote:
Originally Posted by Ivan Azymov  /t/1474221/faital-pro-8hx200-measurements#post_24355357


I just noticed the note at the bottom of the graph, which shows these are not on-axis and the common off-axis permutations. Nonetheless, your on line measurements match the published response curves almost identically, so at least that helps verify the on-axis. I will try to find a cut-away view of the driver to decide if risking a purchase to do off-axis response will be a worthy venture.


My main concern is coloration and off-axis response output decline at 30 degrees.


Nonetheless, thank you for the data.

I did take off axis measurements, but I am not sure I kept them. Let me look for them tonight and if I have them I will post them. The tweeter response was fairly easy to deal with in the XO; but the mid response is pretty rough, especially in the XO region and took a lot of components to get a decent response.
 

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Discussion Starter #11
Here are the mid and tweeter on and off axis plots. I took the off axis plots with a slightly different setup than I did the on axis so the off axis plots are only valid down to about 500 Hz. I have offset the 3 measurements in the plots by 3db each to make them easier to read. As for what is audible and what is not, the woofer breakup is clearly audible and also showed up in the distortion plots (didn't keep those) and it needs to be dealt with in the XO. As I mentioned, the tweeter response isn't too bad compared to some coaxials on axis and is pretty smooth off axis.



 

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Quote:
Originally Posted by djarchow  /t/1474221/faital-pro-8hx200-measurements#post_24360042


Here are the mid and tweeter on and off axis plots. I took the off axis plots with a slightly different setup than I did the on axis so the off axis plots are only valid down to about 500 Hz. I have offset the 3 measurements in the plots by 3db each to make them easier to read. As for what is audible and what is not, the woofer breakup is clearly audible and also showed up in the distortion plots (didn't keep those) and it needs to be dealt with in the XO. As I mentioned, the tweeter response isn't too bad compared to some coaxials on axis and is pretty smooth off axis.




Impressive.


The response appears acceptable both on and off axis (for my purposes, anyway). I will definitely consider them in my prototype when I arrive at that stage of the design. I have looked at other coaxials, but their jagged response leaves alot to ne desired. One matter of difficulty will be trying to find a tweeter I feel comfortable loading with a low crossover frequency. Polyester may be the way to go, even if it results in a more nuanced upper response.


I have considered rolling my own coaxial, but 6.5" appears to be near ideal. Nonetheless, I may be after the impossible--a coaxial I can cross at no less than 2.5kHz sans undesirable side effects (my ears are very sensitive to irregularities anywhere in the 400Hz to 2.5kHz range).


Thanks, again.
 

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Quote:
Originally Posted by coctostan  /t/1474221/faital-pro-8hx200-measurements#post_24356150


Basically no, the HF response of pro coaxes will all be ragged in the upper frequencies because of how the HF CD mates to the throat of the coax driver. The pro driver manufacturers basically all use similar designs for these coax's where the CD transitions into the cone and it is always a compromise that negatively affects HF response. In pro use it is generally not a problem and speakers like the Seaton Cat's and JTR Triple have shown that it is not a deal breaker in Hifi and HT use.

I see that ambition is indeed lacking with present manufacturers. One would think that desiring to be the best in a specialty would progress beyond the marketing department.


I suspected nothing had changed with coaxials, but the frequency response of the faital model is acceptable (for now). I have made it a priority in a prototype to integrate everything into my design sans the face of the driver itself. This should yield better results than standard fare.
 
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