3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

[Jeff B.]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

The phase is fine, so is the impedance. The phase wrap is a result of the crossover and acoustic slopes.

If you don't mind, flip the mid polarity and post the result to see how deep the reverse nulls are (phase tracking).

Pete, I am surprised you didn't mention that there is no crossover roll-off below 1khz for the ribbon tweeter.
Henry, what is your highpass circuit for the tweeter?

[henry218]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

hi jeff,

its 3.9uf, LR2 @3khz.

pete,

here is the reversed midrange. actually something bothering me also, i need to reverse both midrange and tweeter to get flat response.




cheers
henry

[henry218]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

i think its prob not deep enough. :(

[henry218]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

allright,

i added 1mH for the RAAL, prob better for safety and preserving power handling.

here's the responses, transfer function and impedance


cheers
henry

[Pete Schumacher]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

Pete, I am surprised you didn't mention that there is no crossover roll-off below 1khz for the ribbon tweeter.
Henry, what is your highpass circuit for the tweeter?

I did notice that, but I assumed that he was using a single cap. The actual transfer function at the ribbon itself would still be a 2nd order electrical transfer function due to the transformer circuit.

[Pete Schumacher]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

hi jeff,

its 3.9uf, LR2 @3khz.

pete,

here is the reversed midrange. actually something bothering me also, i need to reverse both midrange and tweeter to get flat response.

[ATTACH=CONFIG]38215[/ATTACH]
[ATTACH=CONFIG]38216[/ATTACH]

cheers
henry

LR4 keeps drivers in phase. LR2 requires one to be reversed. So with a woofer/mid LR2, you need to reverse the phase of the mid. And with LR4 to the tweeter, tweeter need to be in phase with the mid. That means both mid and tweeter will be out of phase with the woofer. Does your baffle allow the tweeter and mid acoustic centers to be aligned?

Adding the inductor can't hurt, but there's a primary inductance built into the tweeter. Your first XO was probably just fine, but if you're getting better phase tracking with the extra inductor, why not?

[henry218]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

thanks pete, i know you got plenty experiences with raal. your comment just made me confident that this xo will actually works

[r-carpenter]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

now the fun part starts. Keep the crossover external. Massage the tails of the drivers response, listen to different variants and slopes. Mini DSP is actually very good for it. You can change the slopes digitally and listen to the effects and after you are satisfied with the outcome, execute it with passive components.

[Jeff B.]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

I did notice that, but I assumed that he was using a single cap. The actual transfer function at the ribbon itself would still be a 2nd order electrical transfer function due to the transformer circuit.

I think I figured out what he did - he measured his RAAL response and impedance with the cap in place. PCD sees that as the driver impedance which then cancels the predicted roll-off although it's actually there in reality.

What I do is measure my ribbons with a cap in place, then I manually extend the response of the tweeter wherever it begins to roll-off an extract the phase. I also measure impedanc without the cap. When I import these files I can then model the crossover accurately for the parts I am using.

[henry218]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

hi jeff,

you are correct

cheers
henry

[Pete Schumacher]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

I think I figured out what he did - he measured his RAAL response and impedance with the cap in place. PCD sees that as the driver impedance which then cancels the predicted roll-off although it's actually there in reality.

What I do is measure my ribbons with a cap in place, then I manually extend the response of the tweeter wherever it begins to roll-off an extract the phase. I also measure impedanc without the cap. When I import these files I can then model the crossover accurately for the parts I am using.

We actually measure the ribbons with no crossover in place at all. We just limit the signal size to no more than 2.83V and start the sweep at around 300Hz. We've never damaged a RAAL using that method to measure it's response.

[Jeff B.]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

We actually measure the ribbons with no crossover in place at all. We just limit the signal size to no more than 2.83V and start the sweep at around 300Hz. We've never damaged a RAAL using that method to measure it's response.

I have done that too, and that's how I measure other tweeters, but about ten years ago I cooked an Aurum Cantus ribbon (only driver I ever ruined designing speakers) and since then I use a cap on ribbons. Part of my reason is also due to the near short circuit they present at low frequencies. It's just simple for me to take measurements with a larger cap and then extend the response manually.

[henry218]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

hi pete,

thanks for that, just checked the omnimic's track listing, it does have sine sweep with bass remove

cheers
henry

[Face]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

I have done that too, and that's how I measure other tweeters, but about ten years ago I cooked an Aurum Cantus ribbon (only driver I ever ruined designing speakers) and since then I use a cap on ribbons. Part of my reason is also due to the near short circuit they present at low frequencies. It's just simple for me to take measurements with a larger cap and then extend the response manually.

RAAL's impedance is near a dead short at low frequencies too, I would also recommend using a cap. http://www.raalribbon.com/images/products/70-10-m.htm

[henry218]

Re: 3way Kappalite 3012LF + Satori 4ohm + RAAL 70-10D

impedance chart on the 3way. i think the PCD is accurate 100%, what a great tool it is. Jeff, again you have made such an excellent tools for regular guy such as me to create a good speakers, cheers

btw the PCD screenshot is not the simulated impedance, it just shows better for the phase angle.