Why do only US makers focus on time coherency?


Just curious...it seems that the handful of truly time and phasecorrect speaker makers...Vandersteen,Thiel,Meadowlark,Green Mtn,Thiel,etc,,,are all US based companies...why is this? Are there any Euro/Brit speakers that come to mind? (Besides Quad stats?)
phasecorrect
Dawgbyte: Thanks for the info on that thread. I'll check it out when i get done posting here.

The Ohm F Walsh designs were phase and time coherent, but they can achieve this coherency only at one specific listening height. This height will vary with the distance that one is located from the drivers. The non-linear pitch of the cone for the Ohm A and the use of another radiating source in the Ohm G negate their potential to achieve time & phase coherency. Other than that, the current offerings by Ohm are neither "true Walsh's" or phase & time coherent. While i know that Dawgbyte is not alone in this, people should not lump all Ohm's that refer to using "Walsh technology" or "Walsh driver's" as being one & the same. As far as that goes, the newer Ohm's are NOT EVEN CLOSE to offering 360% of radiation at any given frequency. If you listen to them and like them, that's fine. Just don't buy the marketing hype about "Walsh technology", etc... Sean
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Dawgbyte: From what i saw of Mitch's crossover design from his speakers, Hales are not time / phase coherent. There was an 18 dB / octave crossover in there somewhere if i remember correctly. Sean
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Thanks Sean, I thought the Hales were almost identical in design to Theil's speakers. I stand corrected.