Thiel Owners

Another consideration is the superior time and phase superiority of the Thiels sealed box bass response over the ported, vented, etc. bass output of many subwoofers. Typically the bigger the driver the better the response gets at the lowest 1st octave, but the worse the response gets at progressively higher octaves,.

Dlcockrum, Ordinarily I would suggest that amps with the DR-9's power specs might be adequate, but not necessarily ideal. But, those older Classe' amps seem to be an exception to the rule and work beyond what their specs would suggest. Conservatively/under rated? I don't know. But a lot of Apogee users with their even more challenging load, seemed to indeed be very happy running those older Classe' amplifiers with them.

Richardpo1, Obviously I haven't examined all that many 3.5's without their grills, but the only times I've seen a 4 holed midrange drivers is on mismatched with a 3 hole midrange driver, on used pairs sold on e-bay. I've never seen a pair with two 4 holed midrange drivers. Perhaps different runs of drivers were made with different mounting brackets? I don't know. I'd hazard a guess that the 4 holed drivers might be the off the shelf drivers not made to Jim Thiel's specifications. Not sure what the exact differences might be, if any. Perhaps it's the short coil/ long gap motor, something  else? I really don't know for sure, but until I know better, suspicion would cause me to avoid the 4 hole drivers.

Excellent discussion- All.

Happy Listening!