Found one in a pawn shop. $350. Knob on the "Selectable HF Driver" is upside down - in other words the white indicator line on the knob is down - towards the floor - rather than up so that it aligns with the indicator numbers. For those here who have one of these: Is this a big deal? Does the knob simply pull off? Does this indicate some prior issue and someone tried to "fix it"? 8 ohm, correct? So I can daisy-chain from my Aguilar DB-210 (8 ohm) cabinet, using an Aguilar TH 500? Value? I don't need it, but I might want it.