JBL XPL200 knowledgeable owners: HELP needed please

I've got a question about the crossover network in these.
(I'm not a "technical" guy but something seems wrong to me)
The xpl's come bi amp capable with a switch on the back for "normal wire" and "bi amp"
Remove the jumpers and bi amp them and it sounds as though the crossovers do what they're supposed to do.
But when flipping the switch to "bi amp" it sounds as though a lot more mid freqs come from the woofer.
It's almost like the "bi amp"switch turns the woofer into a full range driver.
Leaving the jumpers on using only one amp and switching from "normal wire" to "bi amp" has the same effect on the woofer.
Is this normal or is something wrong with my crossover networks inside ??

Thanks in advance for the help guys.

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It's almost like the "bi amp"switch turns the woofer into a full range driver.

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Well if you are switching out the series inductor L1 of the crossover you are essentially running them full range. You need the DX-1 or another suitable active crossover to roll the woofer off without the passive network in place.


http://manuals.harman.com/JBL/HOM/Te...XPL200a ts.pdf


Rob:)

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Originally Posted by detroit-rock

...But when flipping the switch to "bi amp" it sounds as though a lot more mid freqs come from the woofer.

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Do you have an appropriate active crossover and amps properly connected, or are you just throwing the switch to see what happens?


Widget

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Originally Posted by Mr. Widget

Do you have an appropriate active crossover and amps properly connected, or are you just throwing the switch to see what happens?


Widget

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I'm not running an active xover.
Though I'm not actually just flipping the switch to see what happens either.
I have pair of amps and they're properly set up: I just happened to notice this when I unhooked one the amps and flipped the switch back to normal.
Night and day difference and easy to hear.
Hearing that had me wondering if this is normal.
I never heard anything close to this when bi amping AR-9's.
Removing the jumper on them caused an immediate separation of the lows, mids an highs causing the woofers to act as subs only.
I was expecting the same with the xpl's but obviously their xover network is very different.
The xpl woofers sounding "full range" certainly brings out a lot more lower/upper mid range and doesn't sound bad at lower listening levels but makes them "scream" at higher levels.
I could certainly use some expert advice/opinions on to go about achieving what the DX-1 achieves when bi amping.
Thanks again for the useful input.
This is an awesome Forum :)

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Originally Posted by Robh3606

Well if you are switching out the series inductor L1 of the crossover you are essentially running them full range. You need the DX-1 or another suitable active crossover to roll the woofer off without the passive network in place.


http://manuals.harman.com/JBL/HOM/Te...XPL200a ts.pdf


Rob:)

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Thanks for sharing that Rob !! :)
Any suggestions on how to go about doing that??
And what is needed

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Originally Posted by detroit-rock

Thanks for sharing that Rob !! :)
Any suggestions on how to go about doing that??
And what is needed

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You probably ought to read the owner's manual: http://www.jbl.com/images/media/XPL_200_OM_EN.pdf

Unless you're using an external crossover you're only bi-wiring with two amps. The "bi-amp" switch should only be used when you have an external crossover to control what frequency ranges go to each amp when bi-amping.

The DX1 is notoriously difficult to find though I believe someone posted a DIY schematic at one point. Here's the manual: http://file:///Users/phil/Downloads/dx1-om.pdf

Alternately you could try the Ashly XR1001 crossover as many of us do with the 43xx monitors. The XPL200A is normally crossed at 300Hz. I'm sure others here have tried it and can be more specific.

When you flip the bi-amp switch two things happen. 1 is that the woofer is connected directly to the input terminals, bypassing all filters. 2 is that the lower frequency of the mid bass filter is changed. It does this to move away from the frequency of the active filter that you are supposed to use in bi-amp mode, so that the filters don't overlap. It would have sounded better to just bypass the lower filter completely. This was previously described by the designer as a compromise required by marketing, to make it possible for a guy who doesn't understand the function of the switches to flip them without damaging the speakers. You are that guy. The bi-amp filter function is illustrated by the dashed red line in the low frequency range of this chart. Red is XPL200A, blue is XPL200. The dashed lines at the high frequencies show the function of the tweeter level switches.

Attachment 62585

In this case, I'd recommend just leaving the switch out of biamp mode.

I've heard them with the very-specific crossover cards designed for this speaker
in the DX-1 and it's quite an improvement, but as obtaining either the DX-1
-or- the XPL200(a) crossover cards is near impossible (and both are needed
to implement the proper crossover... I believe a generic crossover would not
be as successful), why not enjoy them as they are.

You'll be able to make them sound -different- with an external crossover, such
as the Ashly, but the path is wrought with many pitfalls and hurdles for even
knowledgeable/experienced audio types. And there is no guarantee it would
sound -better-.

Manual recommends 250Hz for biamping, if you are interested in continuing
in this direction (not clear if that is for the DX-1 with proper cards, or a
recommended frequency for non-DX-1 crossovers ... guessing the former as
that is the only crossover discussed).

Very nice/enjoyable speakers in any case :)

Wow. THANKS Don.
I really appreciate all the info.
I am indeed that guy !!
I'm relieved to know that my ignorant curiosity hasn't in any way damaged the speakers/xovers.
I'm equally relieved to learn that what I'm hearing is normal.
No doubt I'm out of my element when it comes to the technical aspect of this.
I absolutely love the sound of the xpl200's so I'm going to stick with the plan.
That being bi amping them and now finding the necessary components needed to do it correctly.
....though the "active xover" needed has me questioning my choice of amps.
My plan was to send off one amp at a time for recapping (Yamaha P2200).
But I'm guessing an active xover for these will require 4 amps to do correctly??
I'm not so sure I'm prepared to spend the time and funds to track down another P2200 and have them all recapped.
I'm not so sure I have the room for that setup either.
Any suggestions ?

BMWCCAs post abloe has the owners manual. Read it. It has the answer for you, what they call bi-wiring, but is really passive bi-amping. You remove the jumpers, but leave the switch in the normal position. Active bi-amping gets expensive fast. So don't bother. Aren't these speakers about 25 years old now? About the time you get it working correctly, your midrange speakers will probably wear out due to age, leaving you with a lot of expensive electronics that don't work with your next speakers.

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Originally Posted by Don C

BMWCCAs post abloe has the owners manual. Read it. It has the answer for you, what they call bi-wiring, but is really passive bi-amping. You remove the jumpers, but leave the switch in the normal position. Active bi-amping gets expensive fast. So don't bother. Aren't these speakers about 25 years old now? About the time you get it working correctly, your midrange speakers will probably wear out due to age, leaving you with a lot of expensive electronics that don't work with your next speakers.

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Indeed.
And THANKS again for all the input guys.
There aren't many Forums where the high end, high dollar, experienced and knowlegdeable members will take the time enlighten and share with the "low end entry level" kind of guys like me. :)

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Originally Posted by detroit-rock

There aren't many Forums where the high end, high dollar, experienced and knowlegdeable members will take the time enlighten and share with the "low end entry level" kind of guys like me. :)

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At least there's nothing low-end or entry-level about your XPLs! ;)

In the supplemental manual for the L7, JBL offers this advice to would-be bi-ampers:

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While we don't discourage bi-amplification, we hasten to note that the L7's internal crossover is difficult to improve on. Its phase coherenenc, freedom from distortion, and efficiency rival even the finest (and most expensive) electronic crossovers.

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The XPLs should be at least that good.

Hello ,

I am using the xpl200 in bi amp on a l250 Ti clone with xpl200 components and 250 Ti components ....

Unless you are listening Ac/Dc or Led Zeppelin at full power Bi amp is a great improvment using SS 150 watts for bass and 75 watts minimum Tube amp for the medium/high .

Active Xover is not expensive , Tube Yes ....

I am not sure full SS would be so great compared to a nice SS full range .

Regards

Gerard