Everest DD66000

[Brian DK]

Hi.
A question regarding the low end.
can someone explain why its not possible to use one woofer that goes all the way down to 20hz.
insted of using to woofers that both roll of around 40hz.?

[Mr. Widget]

Simple answer: They wanted to keep the sensitivity above 89dB watt.

The woofers will plumb the depths well, but need a bit of electronic nudging.


Widget

[Valentin]

Two Woofers
Increases sensitivityat low frequency as Widget says
Doublethe radiation area so only have the displacement is needed at agiven intensity /freq , this gives you less distortion. Having two motors givesyou more thermal advantages having a system that will be linear at very highlevels of continuous play . The system will not compress and dynamics will notsuffer linearity and the spectralbalance will be preserved

[4313B]

Hi.
A question regarding the low end.
can someone explain why its not possible to use one woofer that goes all the way down to 20hz.
insted of using to woofers that both roll of around 40hz.?

Simple answer: They wanted to keep the sensitivity above 89dB watt.

The woofers will plumb the depths well, but need a bit of electronic nudging.


Widget

By using a second "helper" woofer, a designer is able to take advantage of the increased sensitivity caused by the bafffle step response of a system. This is how the Everest II maintains its higher sensitivity despite the fact that only one woofer is used up to the horn.

If the second "helper" woofer didn't exist to fill in the bottom end then the crossover network would have to have a mechanism to deal with the baffle step response and the resulting system sensitivity would be exactly what one would expect from a single woofer system.

[Guido]

....insted of using to woofers that both roll of around 40hz.?

I suppose you don't own the Everest DD66000?
You really should not worry because of the datasheet low end roll off of these speakers. In my room I have flat response down to 20Hz.
If you need lower, by a servo sub.
Some people need lower, some not, me not.

The "helper" woofer design was already very successful in the 4435 and is continued with the Ev2 (with finer woofers). It works well

[mech986]

Great info and nice explanation.

[grumpy]

Anyone know the status of the 66000->67000 update kit that was being considered?
(1501AL-2 drivers... perhaps minor x-over changes)

[speakerdave]

Anyone know the status of the 66000->67000 update kit that was being considered?
(1501AL-2 drivers... perhaps minor x-over changes)

Oooo...interesting.

[4313B]

They're having a real tough time convincing Mexico to make them above and beyond what is needed for whole systems.

They have very little interest in making raw drivers.

[grumpy]

Wow... tail wagging the dog. That's just sad.

[4313B]

Evidently Northridge is getting complaints from all over the planet (DD66000 owners).

[Lee in Montreal]

Anyone know the status of the 66000->67000 update kit that was being considered?
(1501AL-2 drivers... perhaps minor x-over changes)

Dos it mean there will be used 1501AL-1 up for grab?

[pos]

Lee, you probably mean 1501AL: the 1501AL-1 is the new iteration made for the 65000.
Looking at the klippel measurements in the EDS that one is a real beast when it come to linearity at high excursion.
I am curious to know how they managed to make this one that much better than the previous 150xAL, as it look very similar in conception (rubber surround).
Or maybe it is just a difference in the distortion measurement technique? (EDS for the "old" ones did not include klippel measurements for that matter...)

[grumpy]

At the very least, the -2 cone is a paper/foam/paper laminate in the latest iteration.
I don't recall if there were other driver changes. Very nicely, the driver info has been
provided and is available in the Technical Reference section if you wish to dig through it.
The designer indicated a fairly strong preference for the new driver, so that was good
enough for me (although it is nice to see the technical differences)

[Brian DK]

I suppose you don't own the Everest DD66000?
You really should not worry because of the datasheet low end roll off of these speakers. In my room I have flat response down to 20Hz.
If you need lower, by a servo sub.
Some people need lower, some not, me not.

The "helper" woofer design was already very successful in the 4435 and is continued with the Ev2 (with finer woofers). It works well

Yes, I own the Everest Dd66000. And I dont realy miss anything.
its the best allround sounding speaker I have heart.

But in some kind of Music I somtimes miss a bit low end, the Music seems a bit bright..