The 215 is essentially two ISA-110 modules from the famous and incredibly rare Focusrite console, in rack mountable format. Everything they did back then was overbuilt and well thought out, not to mention sounded awesome. This unit in particular is very low noise, and everything is working just as it should.
I just had this unit serviced back in November by Rob over at World Pro Audio in Los Angeles. Included in the pictures are two graphs with the response curves for both channels, one at Mic level and one at Line. Please feel free to reach out with any questions you may have! The item "Focusrite ISA-215 Dual Microphone Preamp & EQ Rupert Neve Era Just Serviced" is in sale since Saturday, May 4, 2019.This item is in the category "Musical Instruments & Gear\Pro Audio Equipment\Preamps & Channel Strips". The seller is "gfo_38" and is located in Los Angeles, California. This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Bahamas, Israel, Mexico, New Zealand, Singapore, Switzerland, Norway, Saudi arabia, Ukraine, United arab emirates, Qatar, Kuwait, Bahrain, Croatia, Malaysia, Barbados, Brunei darussalam, Bolivia, Guadeloupe, Iceland, Jordan, Cambodia, Sri lanka, Maldives, Uruguay, Taiwan.