How does this Impedance Response look?

[czag]

I know this is not optimal, but I am wondering if this impedance would cause problems for a decent amp. The phase does dip to about -50 degrees in two places. I would use it with a B&K AVR307 receiver, which has a fairly stout amplifier section. It has a 700VA transformer with 6 output transistors for each of the LCR channels and 4 each for the surround channels, with 130,000 uF of capacitance overall. Also, if it would be fine for my B&K, would it cause problems for just a standard av receiver such as a mid level Onkyo or Yamaha.

http://techtalk.parts-express.com/picture.php?albumid=321&pictureid=3483

Thanks,
Chris

[Pete Schumacher ®]

I know this is not optimal, but I am wondering if this impedance would cause problems for a decent amp. The phase does dip to about -50 degrees in two places. I would use it with a B&K AVR307 receiver, which has a fairly stout amplifier section. It has a 700VA transformer with 6 output transistors for each of the LCR channels and 4 each for the surround channels, with 130,000 uF of capacitance overall. Also, if it would be fine for my B&K, would it cause problems for just a standard av receiver such as a mid level Onkyo or Yamaha.

http://techtalk.parts-express.com/picture.php?albumid=321&pictureid=3483

Thanks,
Chris

It's just fine.

The only time you really need to worry about large fluctuations in impedance is if you're using an amp with a higher output impedance, like many valve amps.

[Sydney]

Chris:
At the lowest negative phase angles: the impedance is NOT at a low points:
You should be fine.

[Pete Schumacher ®]

Chris:
At the lowest negative phase angles: the impedance is NOT at a low points:
You should be fine.

phase is the derivative of the impedance. the higher the impedance slope (rate of change), the greater the angle. The highest phase angle will never occur at the lowest impedance since at that point the impedance is changing the slowest.

[Sydney]

...The highest phase angle will never occur at the lowest impedance...
That is not true.
I have plenty of test results from many sources of numerous cabs that present those attributes:
These speakers are noted for placing an extreme current load at those frequencies.
It is the Otala effect ( noted in Matti Otala's 1983,1985 AES papers ). It places a high EPDR at those frequency points.
Having the same amplifiers for decades I can attest to the difference placed on them by various reactive loads that have a combination of high negative phase and low impedance.