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Looper's Delight
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Rick, the professional percussionist, said: > The trouble with condenser microphones is that they have a > fairly omni directional pickup pattern which makes them > highly susceptibale (sp?) to feedback under normal monitoring > situations. Frankly, I do not understand this here. From what I thought I learned, the polar pattern results a) from the working principle of the transducer (i.e. either pressure-sensitive: only one side of the membrane is hit by the sound - this is an omni or pressure-gradient-sensitive: both sides of the membrane are hit by the sound - this is an eight) b) any constructional means of generating a specific run-time increase to one side of the membrane (which can turn an eight into e.g. a cardioid pattern) c) electrically combining two membranes (omni+eight=cardioid) d) the geometric dimensions of the microphone The polar pattern is to some degree frequency-dependant: while low frequencies easily "wrap around" the microphone, thus always hitting both sides of the membrane in a pressure-gradient mic, high frequencies only reach the side of the microphone they are directed at. And with that, back to your statement, why do condenser microphones always have a fairly omni directional pickup pattern? > One condenser microphone in particular, the AKG C1000S, > has a special > plastic 'focuser' that, when placed over the microphones > element, narrows the pickup pattern to a very, very narrow > cartoid pattern. According to AKG, it turns the cardioid pattern into a hypercardioid pattern, see here (p.24): http://www.akg.com/mediendatenbank2/psfile/datei/75/c1000s_LED4055c4360b704. pdf For comparison, the SM57 (p.2): http://www.shure.com/stellent/groups/public/@gms_gmi_web_ug/documents/web_re source/us_pro_sm57_ug.pdf According to the polar patterns both manufacturers specifiy, the attenuation from the rear @125Hz is 'round 20dB and and about 5dB from the sides. >From my experience, the SM57 tends to mask some frequencies when hit by >high SPLs with another frequency. That, combined with the (perceived) higher sensitivity of the C1000S could lead to the observation that the SM57 more efficiently rejects the unwanted (mostly softer than the wanted signal) sound sources. Rainer