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Old 5th January 2009, 01:14 AM   #21
tinitus is offline tinitus  Europe
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Fore hifi Fostex ought to be the ones to loook at, as they are made especially fore what you want
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Old 5th January 2009, 08:38 AM   #22
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Quote:
Originally posted by tinitus
Fore hifi Fostex ought to be the ones to loook at, as they are made especially fore what you want

But the Fostex will be even better regarding disperssion and integration with the 1" compression driver/horn combo ?
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Old 5th January 2009, 09:14 AM   #23
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Sorry, I made a mistake.

But the Fostex will be even better regarding disperssion and integration than the 1" compression driver/horn combo ?
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Old 5th January 2009, 03:27 PM   #24
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Right, the smaller the better, a 1" exit driver is a beaming direct radiator with a falling response above ~ 4316 Hz, so to push this point up to 20 kHz requires a ~0.216" exit and depending on how close you want its off axis response to blend to the mids-lower HF horn through at least the XO BW may require a WG be added to the super tweeter (ST) to control its directivity to a lower frequency.

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Old 5th January 2009, 04:21 PM   #25
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Originally posted by GM
Right, the smaller the better, a 1" exit driver is a beaming direct radiator with a falling response above ~ 4316 Hz, so to push this point up to 20 kHz requires a ~0.216" exit
GM

But some 1" drivers have a flat response more or less all the way up to 17khz. Anyway I think it will be better even just to use mY titanium RCF from 500hz to 4000hz and then the 1" compression driver with horn. I think that is I wnat to go from 4000khz I need a 1" compression driver because the Fostex tweeters wont go that low. The question will be what approach is better?
1. 2" compression driver/horn from 500-4000hz and 1"compresion driver/horn from 4khz to 20khz

or

2. 2" compression driver/horn from 500-8000hz and a Fostex Bullet Tweeter from 8000hz to 20khz?

This question is assuming that the 2" can go to 8khz wihout problems.

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Old 5th January 2009, 07:33 PM   #26
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Quote:
Originally posted by inkasound

1. 2" compression driver/horn from 500-4000hz and 1"compresion driver/horn from 4khz to 20khz

I vote for number one.
My reason for that is that you want to allow the crossover to rob as much of the troublesome energy out of the 2incher as possible.

I havent heard the DE25 that i know of/can remember, but some googling only showed positive responses.
It has also won some german hifi awards so hopefully it wont be too bad...
However, that one only extended to approx 17-18KHz, which is slightly above what an 1incher is recomended to cover. So you need to decide if that is enough for you, or if you want to add something else above that.
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Old 5th January 2009, 07:43 PM   #27
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Originally posted by electroaudio

I havent heard the DE25 that i know of/can remember, but some googling only showed positive responses.
It has also won some german hifi awards so hopefully it wont be
Thanks for the feedback. Could you advice me on another 1" compression driver for that tasK?

Quote:
Originally posted by electroaudio


I vote for number one.
My reason for that is that you want to allow the crossover to rob as much of the troublesome energy out of the 2incher as possible.
So, in any case is always better to use a 2" only from 400 to 4-5khz, in its comfort zone, right?
As for the 18khz extension of the 1", mostly all 1" are like that. The 2" that reach 20k more or less have the same slope at 18khz that the 1" inchers, with the difference that the 1" reach there with less trouble.
The supertweeter will be the last step. If the Test with the titanium RCF from 400-4000hz doesnt work so well I will change it for a Community M200.
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Old 5th January 2009, 08:03 PM   #28
tinitus is offline tinitus  Europe
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1.4" and 2" from FaitalPro both seems to have a 75mm voicecoil, and the same goes fore Beyma too

Does that mean they have the same diaphragm, but only different throath, and compression ratio
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Old 5th January 2009, 09:55 PM   #29
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Quote:
Originally posted by inkasound

But some 1" drivers have a flat response more or less all the way up to 17khz.

.......I need a 1" compression driver because the Fostex tweeters wont go that low.

The question will be what approach is better?
Only on axis and with the right WG which is why they typically don't publish PWT or polar plots.

And why I said they may need a large WG to blend them, i.e. load them to a lower frequency.

Assuming this is for HIFI and not prosound:

#3. Sell/swap the 2" for 1.4" to ~5 kHz and use one of the several Fostex or other brand choices for the top end.

If you insist on a 1", then I recommend these, ditto the 1.4": http://www.greatplainsaudio.com/hf_drivers.html

GM
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Old 5th January 2009, 10:30 PM   #30
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Quote:
Originally posted by GM


Assuming this is for HIFI and not prosound:

#3. Sell/swap the 2" for 1.4" to ~5 kHz and use one of the several Fostex or other brand choices for the top end.

GM

Thanks for the advice. Yes, its for Hi Fi. If I do it that way I will have to cross the Fostex tweeter around 7khz no lower. That's the safest lower area to start using it.
I prefer to use a a bigger diaphragm for the frequency range between 400hz and 5000hz, I believe the bigger diaphragms sounds fuller, the RCF has a 3" inches diaphragm and the Community M200 a 2".
I was going through the great plains website and the 390 looks interesting, it goes down all the way to 300hz and its a phenolic diaphragm. Sorry they dont have frequency response graphs.

Alan

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