Quick x-over question

[shizzzon 461]

When an active x-over is set, amps that power mids and highs, do the x-overs on these amps need to be set to Full Pass?

Also, amps that power subwoofers, do these amps' LPF need to be set as high as possible? and if their is a subsonic filter on the active x-over, does the subsonic filter on the amp need to be set as low as possible?

[johnecon2001 82]

Wow, someone taught you wrong lol

We'll start at the bottom with subs. The LPF should be no higher than 80hz in a typical install. I prefer mine to be crossed over lower than that even. You subsonic filter only applies to ported subwoofer enclosures. You set that to right below your ported frequency to avoid damaging the sub.

Your mids need to be bandpassed. Depending on what mids you have you'll have a varying HPF and a varying LPF. The same applies for your tweeters. Although, you probably won't need an LPF on them.

[///M5 2,833]

If you use an external crossover I would shut the ones on your amps off.

[shizzzon 461]

ok, hehe, kinda misunderstood what i was askin.

johnecon2001- i know how to setup an active x-over, but as what ///M5 said about shutting the x-over's off the amps, --

What if i can't?

If i purchase amp(s) where you cannot shut the filter off, don't i just run the mid\high amp full pass and the sub amp at high LPF with subsonic filter as low as possible?

If the Active X-over cuts and narrows all frequencies before it reaches the amp, it only makes sense to me to open the amp's playable frequency range up as much as possible so i do not accidentally cut more frequencies out than wanted\needed.. So, is that correct procedure for that scenario?

[johnecon2001 82]

Yes, that is what you should do.

[///M5 2,833]

Still going to effect the phase though. What sort of amps don't allow you to shut them off?

[shizzzon 461]

Man, unless, and i am serious too!, i am completely retarded, all the amps i have owned in the past including ones i have been researching do not allow you to turn off the x-overs on the amp itself.

I am not familiar with "phase issues" unless it's completely out of phase (wired backwards or total cancellation issues).

Take, for example, the Sundown 3000D. I do not see a way to disable it's x-over.

Or 2\4 channel amps that force you to choose LPF\Full\HPF with no on\off switch.

To tell you the truth, i have never seen an amp that lets you bypass the onboard crossover.

Ok, after researching JL Audio(because i noticed it was in your sig, ///M5) that JL audio allows this, but none of the amps i am researching do.

Anyways, phase issues... care to explain or am i to try and set the x-overs on the amp as close to the x-overs of an external active x-over as possible and pray that i chose amps with the same slope as the ex active x-over is using?

[///M5 2,833]

full = off...

I didn't say phase issues, just that all crossovers will effect the phase response.

[shizzzon 461]

gotcha, but doesn't exist on sundown, not their fault personally, most to all class d amps are like this.

i am still lost on phase response... I thought you meant phase issues. As you can tell i am not fond of this area.

Or i might know what you are referring to and just not realizing it....