blown 6"

[billfitzmaurice]

With "destructive wave front interaction" do you mean phase cancelation in the overlapping freq area because of the phase shift caused by the crossover?

Overlapping driver outputs, which you don't want, the cab will sound different depending on the listening position.

It was not a melted voice coil

Then what was it?

 

[Papa Dangerous]

Hm.. No Jokes on the title of this thread? I am not going to be the one to say it...

 

[staindbass]

tear the midrange apart and inspect where it broken if its blown ? maybe one of the leads came off.

 

[staindbass]

Hm.. No Jokes on the title of this thread? I am not going to be the one to say it...

are you implying his voice coil is underhung ? lol

 

[Matthijs]

Overlapping driver outputs, which you don't want, the cab will sound different depending on the listening position.
Then what was it?

The driver is making a loud rattling sound at almost all volumes. So I guess the voicecoil is still working and something else broke due to overexcursion.

 

[Matthijs]

Hm.. No Jokes on the title of this thread? I am not going to be the one to say it...

I can't believe that took 22 posts.

 

[Matthijs]

Well in that case we have to assume mechanical damage.
So its time to upgrade the midrange units:
Invalid Link Removed

I'm going with a better crossover first. I would have to replace the mid speakers in both cabs and those 18-sounds cost a lot more.

 

[Papa Dangerous]

are you implying his voice coil is underhung ? lol

I can't believe that took 22 posts.

Hey.. I never said anything, just making an observation

 

[billfitzmaurice]

The driver is making a loud rattling sound at almost all volumes. So I guess the voicecoil is still working and something else broke due to overexcursion.

That loud rattling sound probably is the voice coil. There isn't anything else to break from over-excursion.

 

[Matthijs]

So, now I've calculated for a 2nd order lowpass/ 3d order highpass at 1100 hz. With a 2nd/3d order combination, should i reverse the phase on the mid, or leave the polarity as it is? Would there be a relevant advantage to making the high pass 4th order?

 

[BassmanPaul]

I can't believe that took 22 posts.

I find it sad that it was posted at all! :scowl:

 

[billfitzmaurice]

should i reverse the phase on the mid

Not where the crossover is concerned, as the total phase shift is not 180 degrees. Time align might result in one or the other being better. You'd need accurate measuring gear to tell.

Would there be a relevant advantage to making the high pass 4th order?

More protection. Might not help, can't hurt.

 

[Matthijs]

So, Bill, would you generally advise against crossovers without a clear 180 or 360 degree phase shift?

 

[billfitzmaurice]

So, Bill, would you generally advise against crossovers without a clear 180 or 360 degree phase shift?

What's almost always advised against is a 2nd order/2nd order crossover, as that guarantees 180 degrees of phase shift. Plus a 2nd order high pass is questionable as far as driver protection is concerned.

 

[Matthijs]

I installed the new crossover and a replaced the 6". I only replaced the crossover in one 12/6 cab, so I had a chance to compare them. The difference is bigger than I expected. The main difference is below what I thought of as the crossover frequency. The old crossover must let through a lot of stuff thats out of phase with the 12", because there's a lot more mid to low mid content. The overall result is warmer and fuller.

 

[greenboy]

Should have a lot better imaging now too, which maybe a bass player doesn't always notice, but it's sure apparent over a wider soundfield. Crossovers really MATTER!

 

[qts]

Hey Matthhijs, do you think your 2nd/3rd crossover at 1100 hz will match with my D12LF + La6 cbmr configuration?
If i look at the specs of both it could be

 

[Matthijs]

Should have a lot better imaging now too, which maybe a bass player doesn't always notice, but it's sure apparent over a wider soundfield. Crossovers really MATTER!

Well I know now! I must admit I have thought of them as a nesscesary bit: as long as you didnt do something completely wrong it would not matter that much. Lesson learned

 

[Matthijs]

Hey Matthhijs, do you think your 2nd/3rd crossover at 1100 hz will match with my D12LF + La6 cbmr configuration?
If i look at the specs of both it could be

I had no chance to compare the specs of the LF with the normal deltaltalite. Are the efficiency and the impedance the same at 1100 hz? Then it might work, i could send you a parts list.