Maybe this unit could share the same benefit as the Alesis 3630 mods. My unit gets used now. Not on single drum hits, still not clean enough but for distorted guitar buss, it's in. Somebody here must have information on the chips your talking about. Remember 2180xx's are pre trimmed, 2181xx's require trimming to achieve there better distortion specs. Matched with the 2252's (if they share the same topology) the 266xl may be back in use for you. They are a steal on E-bay. I have my eye out for one now. I think someone has mentioned V1's on this forum. Search it here. Gotta go. :grin: