{"product_id":"coil-audio-ca-70s-single-channel-mic-line-amplifier","title":"Coil Audio CA-70S MK1 Single Channel Mic\/Line Amplifier","description":"\u003cp\u003eThe \u003cstrong\u003eCoil Audio CA-70S Single Channel Mic\/Line Amplifier\u003c\/strong\u003e is based on a two-stage circuit invented by Western Electric in 1913. It was licensed and built by various audio manufacturers from the 1930s through the 1950s. RCA, Gates, Western Electric, and Langevin were just a few that utilized this elegant and simple single-ended design. With the addition of a flexible input pad network, Coil's Negative Feedback tone shaping, and inter-stage volume control, it's like Mid Century with a Modern twist.\u003c\/p\u003e\r\n\r\n\u003cp\u003eEach amplifier utilizes CT110HN and CT41 custom transformers, as well as the same high end and vintage components as our larger PS6 modules.\u003c\/p\u003e\r\n\r\n\u003ch3\u003eTHE CONTROLS\u003c\/h3\u003e\r\n\r\n\u003cp\u003eThe (INPUT) Pad section contains a Mic\/Line selector, phase reverse switch, and a 4 position attenuation network of Balanced H-pads.\u003c\/p\u003e\r\n\r\n\u003cp\u003eThe LINE\/MIC switch toggles between LINE or MICROPHONE level inputs. Select “MIC” for standard low level microphone signals. Select “LINE” for any balanced line level signal such as the output from a tape machine, DAW, mixer, keyboard, drum machine, or other pre amps. “LINE” mode allows it to work as a tone shaper\/booster for other outboard gear, a second-stage booster for other preamps, or a summing\/buss amp for program or mix material. It also enables easy chaining of multiple amplifiers to create the multi-stage, high gain signal path of a vintage tube console.\u003c\/p\u003e\r\n\r\n\u003cp\u003eThe Rotary Selector switches between 0, -6, -12, and -19 dB input pads. This allows the input to handle high output microphones or loud signal sources. These pads are in the path whether you are in “LINE “ or “MIC” mode.\u003c\/p\u003e\r\n\r\n\u003cp\u003eThe NF and LOW controls   interact to create a unique tone-shaping circuit.\r\nThe NF control varies the amount of Negative Feedback present in the circuit. Counter-clockwise brightens and moves the sound forward while raising harmonics and sensitivity. Turning it clockwise increases negative feedback, producing a darker tone with a smooth, dampened harmonic structure.\r\nThe LOW switch reacts with the NF, boosting or cutting low frequency while moving the low end from front to back in the sound stage. Most effective when the NF knob is between 11:00 and 5:00, The more Negative Feedback, the more reactive.\u003c\/p\u003e\r\n\r\n\u003cp\u003eThe OUTPUT control knob is placed between the 1st stage 6J7 and 2nd stage 6C5 tubes.\r\nIt sets the final level and offers further control of the two-stage gain structure.\u003c\/p\u003e","brand":"Coil Audio","offers":[{"title":"Default Title","offer_id":44450405482599,"sku":"114782","price":1899.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0658\/8848\/5479\/files\/1coil-ca-70s_114782_1.jpg?v=1787092931","url":"https:\/\/vintageking.com\/products\/coil-audio-ca-70s-single-channel-mic-line-amplifier","provider":"Vintage King","version":"1.0","type":"link"}