Leeboy, I don't know of any 88 note arranger with aftertouch...Roland's KR-series don't(or didn't, in case they aren't still being made) have it, and Korg's PA-588 doesn't either.
Apparently, the "experts" say that aftertouch "interferes with the feel of an 88 note graded hammer action", but, I'm not an expert, so I really can't say that it is true.
I suspect an 88 note hammer action with aftertouch might be a tad more than $10.00 more to make than one without, but hey, remember, I'm no expert.
So, why don't Korg and Roland implement aftertouch on their 88 note arrangers?
Ian
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Yamaha Tyros4, Yamaha MS-60S Powered Monitors(2), Yamaha CS-01, Yamaha TQ-5, Yamaha PSR-S775.