{"product_id":"wmd-qaaf-black","title":"WMD QAAF : BLACK","description":"\u003cdiv class=\"top\"\u003e\r\n\u003cp\u003eThe WMD Quad Anti Aliasing Filter (QAAF) was conceptualized as the first epansion for the Phase Displacement Oscillator. It is designed to eliminate aliasing and stair-step distortion from the Digital to Analog converters. We opted to make this a seperate module because it is useful by itself as well as coupled with the PDO.\u003c\/p\u003e\r\n\u003cp\u003eThere are four independent filters inside the QAAF. Each -24dB\/octave Butterworth filter runs at exactly the same frequency. The Butterworth filter has a small amount of resonance and a great sound. Each input jack is normaled from the expansion header that connects to the PDO, but any signal can be filtered by plugging in.\u003c\/p\u003e\r\n\u003cp\u003eThe frequency control circuitry uses a vactrol to control the clocking speed of each filter, slowing down the response to transient signals. This brings life and character to the sound.\u003c\/p\u003e\r\n\u003c\/div\u003e\r\n\u003cdiv class=\"columnLeft\"\u003e\u003ccenter\u003e\u003c\/center\u003e\u003c\/div\u003e\r\n\u003cdiv class=\"columnRight\"\u003e\n\u003ccenter\u003e\u003cspan class=\"bigboldgrey\"\u003eFeatures\u003c\/span\u003e\u003c\/center\u003e\r\n\u003cul\u003e\r\n\u003cli\u003eFour 4-pole filters\u003c\/li\u003e\r\n\u003cli\u003eChannel to Channel Freq +-0.5%\u003c\/li\u003e\r\n\u003cli\u003eSwitched Capacitor Design\u003c\/li\u003e\r\n\u003cli\u003eButterworth Response Curve\u003c\/li\u003e\r\n\u003cli\u003eCV Input\u003c\/li\u003e\r\n\u003cli\u003eFrequency Offset Knob\u003c\/li\u003e\r\n\u003cli\u003eClock Input\/Output\u003c\/li\u003e\r\n\u003cli\u003eMix Output\u003c\/li\u003e\r\n\u003cli\u003eLow-Frequency Limit Jumper\u003c\/li\u003e\r\n\u003cli\u003e4 HP\u003c\/li\u003e\r\n\u003cli\u003eGreat for Pre \u0026amp; Post Filtering\u003c\/li\u003e\r\n\u003c\/ul\u003e\r\n\u003c\/div\u003e\r\n\u003ccenter\u003e\u003c\/center\u003e\u003ccenter\u003eControls and I\/O\u003c\/center\u003e\r\n\u003cp\u003e \u003c\/p\u003e\r\n\u003cp\u003e\u003cspan class=\"boldgrey\"\u003eCV Input\u003c\/span\u003e - This input is roughly calibrated to 1v\/octave. It drives a vactrol that will cause the QAAF to open quickly and close slowly.\u003c\/p\u003e\r\n\u003cp\u003e\u003cspan class=\"boldgrey\"\u003eFreq Knob\u003c\/span\u003e - This knob controls the cutoff directly or acts as a bias\/level shift control for the CV input.\u003c\/p\u003e\r\n\u003cp\u003e\u003cspan class=\"boldgrey\"\u003eCLK\u003c\/span\u003e - This jack serves as a clock input or output, directly controlling the filter's frequencies at a ratio of 100:1. A jumper on the back (lower jumper) selects it's mode. Jump for clock output, leave open for clock input.\u003c\/p\u003e\r\n\u003cp\u003e\u003cspan class=\"boldgrey\"\u003eInputs 1-4\u003c\/span\u003e - Audio Inputs, these are normaled from the expansion header going to the PDO. This normal is broken by plugging into these jacks.\u003c\/p\u003e\r\n\u003cp\u003e\u003cspan class=\"boldgrey\"\u003eOutputs 1-4\u003c\/span\u003e - These jacks are for each channel's outut.\u003c\/p\u003e\r\n\u003cp\u003e\u003cspan class=\"boldgrey\"\u003eMix\u003c\/span\u003e - This output is a sum of each channel's filtered input.\u003c\/p\u003e\r\n\u003cp\u003e\u003cspan class=\"boldgrey\"\u003eFrequency Limit Jumper\u003c\/span\u003e - This rear jumper (upper set of pins) will limit the low frequency cutoff to about 300Hz. This will stop the QAAF from producing aliasing noise itself as it's clock frequency will be limited to 30kHz. Jump for limiting, leave open to disable.\u003c\/p\u003e\r\n\u003cp\u003e\u003cbr\u003e\u003cbr\u003e\u003c\/p\u003e\r\n\u003ccenter\u003eOther Notable Things\u003c\/center\u003e\u003ccenter\u003eThe QAAF is 4HP.\u003c\/center\u003e\u003ccenter\u003eCurrent consumption is 35mA for the +12 rail; 35mA for the -12 rail.\u003c\/center\u003e\r\n\u003cp\u003e \u003c\/p\u003e\r\n\u003ccenter\u003eThe depth from the back of the panel is roughly 40mm.\u003c\/center\u003e\r\n\u003cp\u003eThe QAAF is warranted for 12 months after purchase.\u003c\/p\u003e","brand":"WMD","offers":[{"title":"Default Title","offer_id":41347609034925,"sku":"wmd_qaaf_black","price":229.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0606\/3449\/7197\/products\/qaafpicbig_1.jpg?v=1645060807","url":"https:\/\/www.detroitmodular.live\/products\/wmd-qaaf-black","provider":"Detroit Modular","version":"1.0","type":"link"}