Impedance measurement with 50 feet cable and surround speaker

[Aleks]

Hello.

I would very much like someone to interpret the measurements. I was interested in the effect of a 50-foot-long cable with a resistance of 0.7 ohm on the performance of the surround speaker. What conclusions about the measurement and about the speaker itself would you draw? What causes the oscillations seen in the measurement? Thank you several times in advance.

 

[Aleks]

Additional explanation. The resistance of the wire should not exceed 5% of the nominal value of the speaker. In this case, it is 17.5%. I will replace both. I would like to know what I listened to for years before I delved into the situation.

 

[RogerM]

Impedance trace looks perfectly normal result from a driver. The driver in that enclosure has resonant frequency at 200hz.
Additional resistance of the long speaker cable is added to the speaker. Since the two traces closely follow each other I don't see any problem with the long cable it will just be resulting in a very small (imperceptible to hearing) reduction in dB from the speaker.