The specs shown here indicate an output impedance of 700 ohms, although reviews from some years ago indicate 1.5K.
I would suggest that you try to obtain clarification of that discrepancy from the manufacturer or importer, and, as Bob suggested, try to determine the worst case (highest) output impedance within the range of audible frequencies, which probably occurs at 20Hz.
Regards,
-- Al
I would suggest that you try to obtain clarification of that discrepancy from the manufacturer or importer, and, as Bob suggested, try to determine the worst case (highest) output impedance within the range of audible frequencies, which probably occurs at 20Hz.
Regards,
-- Al