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Old 30th July 2010, 11:47   #211
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Originally Posted by naughty001 View Post
a high pass and a low pass wont be the identical circuit as you outline
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Which means i ll have to design a second order LPF with following values;
L - 0.22 mH
C - 7 F
I was having the MT-22 Tweeter in mind.
Simply if you are lookng at a L-R 2nd order for HPF and LPF.
@700Hz/12db L-R you are looking at 28uf (27uf or 10+10+6.8uf) and 1.8mH
@4000Hz/12db L-R you are looking at 5uf (4.7uf) and 0.32 mH

However given the drivers you have chosen I'd like to suggest 2 things.

a. the mid and tweeter should be as close together as possible preferably so close that their flanges meet. One could even cut an arc out of the flanges of these two dome drivers to reduce c-c distance. This needs to be done for 2 reasons.
i. at 4kHz the wavelentgth is about 8.5cm this is the recomended c-c distance between drivers
ii. At 2.5 octaves the dome mid's pass band is pretty small (700-4000). Ideally I would prefer 3-3.5 octaves (eg: 500-4k or 700-6k). We would have to higerorder XOs and hence to ensure that the shift from mid-tweeter is not preceptable the 2 drivers will have to as close together as possible.

b. We cannot use a 1st order XO with the mid (either LP or HP) due to the slope beyond the pass band and excusrion limitations. I do not normally like 2nd order XOs as the phase shift peaks are terrible. We might have to consdier 3rd order but the component values are often huge and getting good quality 20uf+ caps is expensive and large value inductors store energy and rob the dynamics.

Given these limitations 2nd order L-R might be your best bet.
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Old 3rd August 2010, 19:39   #212
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Originally Posted by navin View Post
Simply if you are lookng at a L-R 2nd order for HPF and LPF.
@700Hz/12db L-R you are looking at 28uf (27uf or 10+10+6.8uf) and 1.8mH
@4000Hz/12db L-R you are looking at 5uf (4.7uf) and 0.32 mH

However given the drivers you have chosen I'd like to suggest 2 things.

a. the mid and tweeter should be as close together as possible preferably so close that their flanges meet. One could even cut an arc out of the flanges of these two dome drivers to reduce c-c distance. This needs to be done for 2 reasons.
i. at 4kHz the wavelentgth is about 8.5cm this is the recomended c-c distance between drivers
ii. At 2.5 octaves the dome mid's pass band is pretty small (700-4000). Ideally I would prefer 3-3.5 octaves (eg: 500-4k or 700-6k). We would have to higerorder XOs and hence to ensure that the shift from mid-tweeter is not preceptable the 2 drivers will have to as close together as possible.

b. We cannot use a 1st order XO with the mid (either LP or HP) due to the slope beyond the pass band and excusrion limitations. I do not normally like 2nd order XOs as the phase shift peaks are terrible. We might have to consdier 3rd order but the component values are often huge and getting good quality 20uf+ caps is expensive and large value inductors store energy and rob the dynamics.

Given these limitations 2nd order L-R might be your best bet.
a. Trying to see how best to have them together. will post up soon on the same
i. & ii. I think i may go in for the CDM-88 which offers better range. so mostly a BP of 700 Hz - 6000 Hz is feasible with this driver.

b. I really dont even wish to go to second order, as more the passive components more will be the losses. However i think 2nd order is fine for the tweeters atleast. But Why not a Butterworth and why specifically L-R ?
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Old 4th August 2010, 10:13   #213
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a. Trying to see how best to have them together. will post up soon on the same
i. & ii. I think i may go in for the CDM-88 which offers better range. so mostly a BP of 700 Hz - 6000 Hz is feasible with this driver.

b. I really dont even wish to go to second order, as more the passive components more will be the losses. However i think 2nd order is fine for the tweeters atleast. But Why not a Butterworth and why specifically L-R ?
a L-R is 6db down at F3 a butter worth is 3db down. L-R would give you the protection you need and still be 2nd order. Otherwise you'd need an odd order XO and then things get really sticky. I do like 1st/3rd order networks a lot but they need more work.

If the CDM-88 can operate over 3 octaves 700-6k then you should consider a 19mm dome instead of a 25mm dome. Dispersion is better even if power handling and delivery is less. If you are XOing at 6k you could look at a tweeter that has a Fs of say 2kHz, has good disperiosn at say 10khz, and is linear (pistonic with no breakups) to 25kHz. Just a thought.
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Old 4th August 2010, 11:24   #214
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700k-6000hz is slightly high in my opinion. Depending on the amount of power you are gonna use on them it could be crossed lower. Since the midbass is gonna be in doors and the midrange and tweeter on the A-piller I would suggest to cross them at 600hz at 12db to 5000hz at 12db. There is a rolloff after 5khz and it's best to have the midrange running upto 5khz as you get flat response till than.
You could also, look for tweeter as Navin mentioned or get something like the Scanspeak R2004/6020 which is a ring radiator form, can work the best when played on-axis it has slight better flat response from 10khz upto 20khz when played on-axis. MT-23 is good too upto 10k beyond which you would need to EQ them a bit. Cross the tweeter at 5khz at 12db. I have noticed that Morel tweeters sound little better when played them off-axis compared to on-axis, they are more designed to give better result when slight off-axis.
You can decide as per the installation flexibility.

Last edited by Invinsible : 4th August 2010 at 11:26.
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Old 4th August 2010, 12:54   #215
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I have noticed that Morel tweeters sound little better when played them off-axis compared to on-axis, they are more designed to give better result when slight off-axis.
Morel designs them to be used 30 deg off axis.
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Old 4th August 2010, 13:28   #216
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Originally Posted by navin View Post
Morel designs them to be used 30 deg off axis.
My experience with Morel MT12 and 22, have noticed that when set them on A-piller 90 deg offaxis sounded better somehow. It's the reflection that was surely the reason here. I had these tweeters in sphere enclosure and tried them both 30 and 45 deg offaxis. Though the result sounded much smoother compared to previous position some how that warmth was missing. Morels designs it in such a way where the distortion adds a bit of advantage to it.
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Old 4th August 2010, 15:11   #217
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Can someone post a nice picture showing 30 deg and 45 deg off axis placement of tweeters
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Old 7th August 2010, 22:17   #218
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Default Heads up

A blistering hot update tomorrow, Stay tuned guys
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Old 8th August 2010, 22:32   #219
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Default Is there something that is compact, yet powerful ?

Lets face the reality. It is known fact that tube amps are much better in Tonal Quality when compared to digital counterparts. But how many hatches can accomodate 3 or more of those amps ? More so, when you are dealing with extra-ordinary power levels.

ok, why i need so much power ?? Because such is my Sub !!! I am not spilling any more here, as another ultimate update is there in a couple of days.

Coming back to my Amp,
I need something that can put in excess of 800-900 rms (). Now the astonishing part is, i need those R-M-S at 4 ohm ()

How many amps in todays market can do this.? and i am talking about mono only. Imagine the size of such amps !! HOw do i ever fit in a puny Hatch like i10 (for that matter most hatches in that segment).

But, there is Hope. Hope in name of Alpine, Hope in name of PDX and more Hope in name of PDX -MX series.

The M-X Sereis from PDX was newly introduced in market recently. M-'X' comes in two power ratings. the M6, which puts out 600w RMS @ 4 ohms and the almighty M12 which spits out whle 1200w RMS of power. Alpine claims to have recitified few glitches found in earlier first gen PDX Amps. And i trust Alpine, as a brand that they wil keep up their words. and with that hope, i am presentinh you, my superbly sleek, Alpine PDX-M12

Specs:
1200W RMS x 1 @ 4 ohm and 2 ohm
92 dba SNR
>= 0.04 THD+N
Digital, Class D Amp
Thinner than the earlier PDX Amps.

Here are the pics.
Attached Thumbnails
"In Pursuit of Happiness" - The Journey of a True Audiophile-08082010282.jpg  

"In Pursuit of Happiness" - The Journey of a True Audiophile-08082010308.jpg  

"In Pursuit of Happiness" - The Journey of a True Audiophile-08082010281.jpg  

"In Pursuit of Happiness" - The Journey of a True Audiophile-08082010287.jpg  

"In Pursuit of Happiness" - The Journey of a True Audiophile-08082010289.jpg  

"In Pursuit of Happiness" - The Journey of a True Audiophile-08082010291.jpg  

"In Pursuit of Happiness" - The Journey of a True Audiophile-08082010296.jpg  

"In Pursuit of Happiness" - The Journey of a True Audiophile-08082010295.jpg  

"In Pursuit of Happiness" - The Journey of a True Audiophile-08082010304.jpg  

"In Pursuit of Happiness" - The Journey of a True Audiophile-08082010307.jpg  


Last edited by Mi10 : 8th August 2010 at 22:35.
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Old 9th August 2010, 10:05   #220
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Mi10, if you need 800-900 watts @ 4 Ohms, I am sure you are going in for the ID MAX dual 2 ohm sub. Am I correct??
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Old 9th August 2010, 12:07   #221
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Mi10, if you need 800-900 watts @ 4 Ohms, I am sure you are going in for the ID MAX dual 2 ohm sub. Am I correct??
ID max is a very efficient sub, infact i could do with even 300-400 rms itslef, as my intention is 'SQ' and not 'SPL'.

So, its not the ID max, but am equaly competitive Sub which is lesser heard in this part of the world.

In most probablity, i ll be laying my hands on it tonight. Wil post the pics then

Last edited by Mi10 : 9th August 2010 at 12:08.
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Old 9th August 2010, 12:19   #222
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Totally hooked to this thread. Great stuff Mi10.
Is it the Morel Ultimo sub? or a Dynaudio Esotar?
Eagerly waiting for the setup to complete.
Quote:
Originally Posted by Mi10 View Post
ID max is a very efficient sub, infact i could do with even 300-400 rms itslef, as my intention is 'SQ' and not 'SPL'.

So, its not the ID max, but am equaly competitive Sub which is lesser heard in this part of the world.

In most probablity, i ll be laying my hands on it tonight. Wil post the pics then

Last edited by thelord : 9th August 2010 at 12:31.
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Old 9th August 2010, 13:53   #223
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Is it the DIYMA sub?? Anybody heard of it??
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Old 9th August 2010, 18:03   #224
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Totally hooked to this thread. Great stuff Mi10.
Is it the Morel Ultimo sub? or a Dynaudio Esotar?
Well, close enough !!!

Quote:
Originally Posted by Pr_007 View Post
Is it the DIYMA sub?? Anybody heard of it??
No, not the DIYMA R12.

Here are few clues;
  • SVC Configuration
  • Fs - 20 Hz
  • Xmax - 25 mm
  • Qts - 0.345
  • Response - 10Hz - 900 Hz (!!!!!)
  • 5.1" Extrernal Voice Coil (Yes, you read it right, its 5.1 inch)
Must be an easy guess now
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Old 9th August 2010, 18:33   #225
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Is it the Morel Ultimo 12" ?

Last edited by Rehaan : 10th August 2010 at 18:05. Reason: Please avoid circumventing the 20-character rule. Thanks.
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