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Original Message
"diminished bass"
Posted by Lew on March 14, 2013 at 06:59:36:
When you say the bass was diminished, do you mean even in a circuit where the value of the capacitor (1uF, in this case) should otherwise have been sufficient to pass low frequency information down to a cut-off of 2 Hz or less? (That's just my rule of thumb; I like to shoot for a -3db point of 2 Hz, in order to have flat response down to 20 Hz.) So, with a 1uF coupling capacitor, the impedance of the following circuit should be no lower than ~100K ohms. That's the approximate lower limit of the parallel sum of all the impedances seen by the output of the capacitor, to achieve a -3db point of 2 Hz.
If this was not the case, then simply increasing the value of the coupling capacitor, using exactly the same brand and type would be expected to improve the perceived bass response.
I ask this question, because I read statements like yours quite often (this or that capacitor has
"no bass") with no further information about the circuit topology. Thanks.EDIT; I realized after writing this that you may well have been referring to an apparent lack in the midbass frequencies and not extreme low bass response that would be affected most by capacitor value and input impedance of the following stage, but it would be interesting to read your response, nevertheless.