Not exactly related, but many moons ago, I first heard of Koch on this board. Now I am selling the one I picked up:
http://www.ebay.com/itm/Koch-TwinTone-Combo-amp-with-extension-cab-/261400041460?pt=LH_DefaultDomain_0&hash=item3cdca817f4 (http://www.ebay.com/itm/Koch-TwinTone-Combo-amp-with-extension-cab-/261400041460?pt=LH_DefaultDomain_0&hash=item3cdca817f4)