Pre to amp Imped or Sensitivity mismatch causing buzz?

[BiggerIsBetter]

As background: My chain is sources (mixed bal and un) to a Carver lightstar passive to an Apogee CRQ-12 parametric to a pair of BSS FDS-310 X-overs to 3 amps (2 bal, 1 not), to the speakers. All connection between the pre and xover are balanced XLR.

I have a buzz, not a low hum. After hunting grounding loops and the like, I ended up with just the xover (no input), directly hooked to the amp with the worst buzz (the mid). Since the buzz was the same with no source connections, and I am going balanced to balanced and tried directly grounding the chasis of the 2 component and lifting the ground of the xover I have concluded that I do not have a grounding problem rather an impedance or sensitivity mismatch.

The xover has an output impedance of 100 ohm and the amp (AR VT-150) has an input impedance of 200K ohm with a sensitivity of 2.3 v P-P. In order to get the buzz down to a barely acceptable level, I need to turn the xover output level to around -12DB.

As a result, given that I am driving this with a passive, I have limited "juice" to drive an acceptable output level.

Is this high noice floor (buzz) due to the impedance mismatch? If so, what are some options....I have a soldering iron and I'm not afraid to use it...

Thanks!

[Dale A B]

My co-worker had a pair of Belle's that had a buzz - turned out to be light fixtures on the same circuit.

NP - Trouble - The Skull (Remaster)

[DrWho]

Do you have cable TV? Try disconnecting the cable jack coming from the wall.

I'm pretty sure an impedance mismatch will not cause buzzing...

[BiggerIsBetter]

No cable, and I ended up disconneting everything so the only thing I had connected was the xover outs to the amp in, both are balanced and XLR. Both where plugged into my power conditioner (panamax) and I also tried plugging them both directly into the wall. With the crossover I was able to determine that the buzz is between 400-800hz.

I also don't thing the impedance mismatch is the problem, even though 100 to 200000 is way over 10:1, the Audio Research BL1 (designed to convert unbal to bal into the VT-150 amps I am using has a 60ohm output, even lower than my xovers 100).

I'm going to try other devices (like the BL1) directly hooked to the amp to see if there is the same buzz. Is so, it might just be amp noise exacerbated by the fact that I am using 116DB sensitive horn drivers with HUGE horns.

Since the xover is pro and the amp is commerical I expect they are looking for different signal strengths, but I just dont get how that results in a buzz and if so what to do about it (I have not seen a balanced to balanced interface box)