12-14-2015, 02:13 PM
Hi,
Yes, I think that about sums it up.
They must have decided that the ISB brought no or very little benefit to the 690 models, because of sound diffusors and their use of high-frequency (actually what we'd call mid-range today) speakers that ameliorated beaming. On top of that the ISB must have complicated cabinet design, adding to cost - unnecessarily in these cases. But were they to drop the X it would appear to potential buyers that something was missing. So it seems they just kept it going with the X and XX.
They were not taking anything away from the set's performance, so the customer did not truly lose out.
Paul
Yes, I think that about sums it up.
They must have decided that the ISB brought no or very little benefit to the 690 models, because of sound diffusors and their use of high-frequency (actually what we'd call mid-range today) speakers that ameliorated beaming. On top of that the ISB must have complicated cabinet design, adding to cost - unnecessarily in these cases. But were they to drop the X it would appear to potential buyers that something was missing. So it seems they just kept it going with the X and XX.
They were not taking anything away from the set's performance, so the customer did not truly lose out.
Paul
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