Possible impedance matching issue with subwoofer?

Koestner, I have only seen these placed between the preamp and cd or dac. Can it be placed between my preamp and sub amps and work fine?

I assume the second set of preamp outs go into the x10 inputs and then I output to the sub's plate amps right? Is this better or the same as placing the x10 between the cd player and pre? Will my preamps output impedance be lowered by placing the x10 between cd player and preamp? Lowered in the same way as placing it between the pre and subs......

Thanks for the responses, but looking for an answer to my question which seems to have nothing to do with true balanced designs .

Al, understand all your comments and thanks. Very interesting stuff here. Quite a lot to know and be aware when adding subs to some systems. Yes, my pre has 3.3uf coupling caps. No, my second output is not buffered separately. I use low capacitance Blue Jean cables that are 10 foot long on the subs.

Davehrab & Al, going from my Altas amp to the sub's high level (binding posts)does not mean the Atlas amp is driving the two subs? Right? The plate amp in the sub still powers the subwoofer and the Atlas amp is simply sending out the signal for the plate amp to amplify. This is the way I have always understood it? Perhaps I am wrong?

This Burson buffer may be just the ticket. Thanks for the idea. On paper it sounds good, anything I'm missing here? Seems it allows me to get the best sound out of my subs as well as my main speakers? It costs $320 however and I wonder if just hooking up my subs from my amp's output is the best and no cost answer? As long as the amp is not driving/powering the subs, but simply sending the signal over for plate amp for amplification.

Al, you are the MAN! thanks so much for your help.

BTW, my pre to amp ic is only 3 feet long. Yes, I use the LC-1 sub cable.

Thanks Nsgarch and Almarg for your comments and help.

Al, the builder told me if the plate amp has the negative high level input grounded or in common with another connector (left minus connected to right minus, then I would need to do a special connection from the Atlas. Connect only one phase of each channel ( presemably the plus) to the high level input.

I will look at the back plates tonight.

Ha, ya a BIG hum is the last thing I need1

Ok, one last question so I can make my final decision. I am not sure I want to go the high level hook up route as I simply don't know how the plate amps are wired. Can't see anything as all the sub binding posts are hooked together on a circuit board with the traces hidden from view. I would have to take boards off etc and I don't want to do all that. My amp is fully balanced and I fear causing an issue due to the way the sub high level inputs may well be wired -Keiga KG 5150.

Bottom line. Is the line level hook up going to cause an issue in terms of impedance mismatch or not? Al comments as well as Nsgarch suggest I will not have an issue in terms of sound degregation. Here are the facts on my gear.

Preamps output impedance is 5k ohms
Plate amps input impedance is 22k ohms
My stereo Atlas amp has an input impedance of 470k ohms
My sub cable is very, very low capacitance -Al referred to it above and they 10 feet long. I run two subs.
My ic's between the pre and amp are 3 feet long

While the music sounds good I do wonder if I am rolling off in the bass area and possibly compromising the sound of my main speakers. Again, both Al and Nsgarch seem to suggest no issue. But some other comments suggest otherwise? I would buy a Buson buffer to place between my pre and subs if that is deemed as best. I understand that such a buffer would reduce what the subs see as output impedance down to under 600 ohms and perhaps as low as 100 ohms.

I would rather not spend the money if there is nothing here to be concerned with. I set my subs to play 40 hertz and below only. Since I have 2 I set the volume very low - near the minimum really.

What do you expert say.

That is what I thought and thanks Al.

Wanted to update folks on my progress. Well I have two subs now hooked up to my system. I have a/b'd the sound with and without the subs. When I turn the subs off I also remove the ic's from my preamp to compare the sound.

No loss of highs. No loss of bass. No bad anything. So what I feared as an impedance mismatch did not materialize. Most interesting as on paper one would think I could have an issue with impedance between my preamp and sub plate amps.

Al, you certainly got this one correct.