Correction circuit for dynaudio driver

[jimbones]

Hi All,

I have a question about the recommended correction circuit for a 17W75 dynaudio woofer. It is a 15 uf cap and 4.7 ohm resistor. Does that go in parallel with the driver?

[Inductor]

Originally Posted by jimbones

Hi All,

I have a question about the recommended correction circuit for a 17W75 dynaudio woofer. It is a 15 uf cap and 4.7 ohm resistor. Does that go in parallel with the driver?

Yes, zobel parallel to driver.

[jimbones]

Thanks, I think the max I can x over this driver is 2500 hz and I am using the Focal T121 tweeter so Iwas thinking a 2nd order and inverting the polarity. The tweeter with anything less than 12db per octave would be dangerous, right?

[Inductor]

Originally Posted by jimbones

Thanks, I think the max I can x over this driver is 2500 hz and I am using the Focal T121 tweeter so Iwas thinking a 2nd order and inverting the polarity. The tweeter with anything less than 12db per octave would be dangerous, right?

Hi,
One question at a time. No is not dangerous if done appropriately. To test for a 1. order (after checking all the data prior to do that) you need to have a space in frequency (one or more octaves) between Fs and the crossover point, as a standard rule, doesn't mean it can't be done with less.

What woofer do you have, I can't assume is a 4/8 ohm (car/home?).
And there are 4 Dynaudio specs models published.
17w75 (this one to 2K5Hz max as you stated)
17w75 ext
17w75 XL
17w75 LQ esotec

What conditions do you have for the drivers (specs), do you have any crossover design you are looking at yet, and location for your speaker, I suppose it's you home. Designing a complete system it's a consequence of all the data and there is no unique answer for the formulated questions you might ask.

[Inductor]

What's the Fs for T121 (is it T121 or TC121?) (specs/curves?). For the Focal TC 120 it's 800/900Hz.

[jimbones]

Originally Posted by Inductor

Hi,
One question at a time. No is not dangerous if done appropriately. To test for a 1. order (after checking all the data prior to do that) you need to have a space in frequency (one or more octaves) between Fs and the crossover point, as a standard rule, doesn't mean it can't be done with less.

What woofer do you have, I can't assume is a 4/8 ohm (car/home?).
And there are 4 Dynaudio specs models published.
17w75 (this one to 2K5Hz max as you stated)
17w75 ext
17w75 XL
17w75 LQ esotec

What conditions do you have for the drivers (specs), do you have any crossover design you are looking at yet, and location for your speaker, I suppose it's you home. Designing a complete system it's a consequence of all the data and there is no unique answer for the formulated questions you might ask.

Ok so lots of questions and answers.
The woofer is the basic 8 ohm 17w75 (Not the Ext or other variant) I am using 2 in parallel in a home audio setup. I do not have a specific xover design, but coming up with one with input on the board.

I can not find specs on the T121. I think the Fs is 1k. it is 92db eff. Hope this helps. Thanks for your help.

[AllenB]

So, you plan to cross the woofer at 2500Hz, one course of action would be to use a single capacitor set to cross the tweeter at 5000Hz (between 3 and 5uF.. is it 8 ohms?) not expecting much but once you listen to it you'll have some clues to set you on the right path.

[Inductor]

There is this 2. order crossover for your tweeter (T121) from Focal (Reference: Plan kit 130).
C1=3.3uF
L3=0.35mH
R1=3R9, R2=1R2
Cabasse - Focal - diyaudio.rs

I don't know the crossover frequency, without simulation, but I guess there will be a gap in frequency output (to high for the woofer?, maybe not). Place an inductor and zobel on the low pass and test.

[Inductor]

Here kit dynaudio with two 17W75 parallel (long extension XL). T/S specs similar.
http://www.gattiweb.com/images/dynaudio/double_3.pdf

[jimbones]

Wow you guys are good! OK so I will draw it up and post and then test.Sweet!