About crossover

[billy]

First order , second order and Third order , which one is better?

[AGGEMAM]

Generally, the simpler the better.

First order series XOs seems to be the mantra of the day.

Now one thing to keep in mind, though. The lower the order of the XO, the higher the demands on the drivers are. Both on having a linear frequency response outside their primary working area and being able to cope with more signal there as well.

[planet10]

The best XO is the one that works best with the drivers you are using.

It is really hard to discuss XOs outside of the context of the speakers they are being used with.

The Full Rangers would say no XO is the best XO.

Personally, i am using a 4th order active XO between my woofers & full-ranges (@125 Hz), the FRs are allowed to run all the way up, and then a single cap XO on the superT at about 10k.

A 1st order XO allows you to get the response to sum to 1 in both the amplitude & the phase plane. But it puts big demands on the drivers you are using and to achieve all the promise the acoustic centres of the drives should coincide (at least in the vertical plane).

Faster XOs mean that you can run a driver closer to its edges, and you have less driver interaction. The Joseph speakers are an example of taking high order XOs to the max -- and they seem to be very highly regarded.

dave

[argo]

billy

Second both answers:
The best XO is one that works best with the drivers you are using - that is, if the drivers will demand even 6th or 8th order to sum flat and keep all resonant breakups at low level enough, this is the way to go.
But also try to keep the circuit as simple as possible - targeting a total response of +-3dB with resonant breakups lower than - 40dB is quite acceptable in most cases.
Sometimes you can do away without using all these resonant trap, impedance compensating and baffle step compensating circuit bells and whistles, taking advantage of driver’s natural impedance and rolloff and selecting the right crossover point.

Another issue is lobbing patterns, which are greatly depending on driver’s sizes, their alignments, crossover frequency and order.
Now, because of room reflections, using the same drivers in the speaker but compounded with different topologies (which are causing different lobbing patterns) can make the same drivers sound very much different in a given room.

planet10

You made me very curious. Can you share what FR and superT you are using and how they are aligned?
I have been trying to use the same setup: 10” Woofer (active 24db/oct low pass @80Hz) + Fullrange (sealed box + active 12dB/oct high pass @80Hz) + supertweeter (6dB/oct @ around 10000Hz)


Argo

[planet10]

Originally posted by argo
planet10
You made me very curious. Can you share what FR and superT you are using and how they are aligned?
I have been trying to use the same setup: 10” Woofer (active 24db/oct low pass @80Hz) + Fullrange (sealed box + active 12dB/oct high pass @80Hz) + supertweeter (6dB/oct @ around 10000Hz)

Argo,

My current speaker system is quite modest, but very musical, decidely Frugal-phile material. They are a set of BD-Pipes with Radio Shack 40-1197s (not heavily tweaked yet). I have been trying many Ts on the top (physically & freq wise). I am leaning towards some little cones on the top. On each side i have a pr of Peerless 8" aperiodically loaded. More pics and info on my website -- BD-Pipes.

dave

[planet10]

Originally posted by argo
planet10
You made me very curious. Can you share what FR and superT you are using and how they are aligned?
I have been trying to use the same setup: 10” Woofer (active 24db/oct low pass @80Hz) + Fullrange (sealed box + active 12dB/oct high pass @80Hz) + supertweeter (6dB/oct @ around 10000Hz)

Argo,

My current speaker system is quite modest, but very musical, decidely Frugal-phile material. They are a set of BD-Pipes with Radio Shack 40-1197s (not heavily tweaked yet). I have been trying many Ts on the top (physically & freq wise). I am leaning towards some little cones on the top. On each side i have a pr of Peerless 8" aperiodically loaded. More pics and info on my website -- BD-Pipes.

What FR are you running?

dave

[argo]

Originally posted by planet10


What FR are you running?

dave

Currently one Jordan JX92S and one Alcone 10" aluminum woofer.
Not decided about supertweet jet - may be some ribbons. But planning to arrange four Jordans and supertweet into DiAppolito with one subwoofer.

Argo

[planet10]

Originally posted by argo
Currently one Jordan JX92S and one Alcone 10" aluminum woofer.

Does the 10 keep up with the Jordan?

Not decided about supertweet jet - may be some ribbons. But planning to arrange four Jordans and supertweet into DiAppolito with one subwoofer.

In a 2.5 way? You'd be pushing to use the Jordans above 4 or 5k in an MTM.

dave

[argo]

Originally posted by planet10


Does the 10 keep up with the Jordan?

In a 2.5 way? You'd be pushing to use the Jordans above 4 or 5k in an MTM.

I think so. The aluminium woof is very musical and accurate
No 2.5 way. I would call it W+MMTMM.
What do you mean by “pushing” above 4 or 5k in MTM?

Argo

[planet10]

Originally posted by argo
W+MMTMM

When 2 sources of the same frequency are futher than a specific fraction of the wavelength of that frequency you start to get comb filtering and you start to lose "focus".

dave