ATC SM75-150 versus SM75-150S

[JonBocani]

Does anyone have T/S data for SM75-150?

Google or Solen.ca

will have a pair of SM75-150 for sale soon, great condition.

 

[mbrennwa]

Does anyone have T/S data for SM75-150?

Here are my impedance measurements of two ATC SM 75-150 / 16 Ω / "non-super" drivers (raw data in ZIP file).

The Thielle-Small parameters I get from this are:
Rdc = 10.6 Ω
f0 = 329 Hz
Qe = 1.1
Qm = 16.2

 

[mbrennwa]

Here are my impedance measurements of two ATC SM 75-150 / 16 Ω / "non-super" drivers (raw data in ZIP file).

The Thielle-Small parameters I get from this are:
Rdc = 10.6 Ω
f0 = 329 Hz
Qe = 1.1
Qm = 16.2

Maybe I should add that the model curve reflecting these parameters is hardly visible on my plot because it is covered by the curve with the measured data of the first unit. The model curve is different from the measured data only at frequencies higher than 10 kHz or so.

Also, fitting the model to the data of the second unit would give a marginally lower f0 value (318 Hz). The differences in the other parameters would be similarly small, if not negligible.