Hi,
Given that the minimum value of an output coupling capacitor in a preamp is related to the input impedance of the amp you intend to drive...
Other than possibly size and cost, is there any theoretical disadvantage to using a larger value capacitor fit for driving a low input impedance solid state amp, when actually driving an amp of much higher input impedance? The difference in value would be something like 2 to 3 uF compared to 0.33 uF.
Thanks,
Alan
Given that the minimum value of an output coupling capacitor in a preamp is related to the input impedance of the amp you intend to drive...
Other than possibly size and cost, is there any theoretical disadvantage to using a larger value capacitor fit for driving a low input impedance solid state amp, when actually driving an amp of much higher input impedance? The difference in value would be something like 2 to 3 uF compared to 0.33 uF.
Thanks,
Alan
It's a matter of lowest common denominator. The IHF "standard" I/P impedance is 10 Kohms. To avoid phase shifts in the audio band, the LF limit needs to be 2 octaves lower. That makes F3 5 Hz. or less. Therefore, the smallest cap. that can be used is 3.3 μF.
Film and foil parts this large are expensive. My preference is a 4.7 μF. metalized polypropylene (MKP) part bypassed by a 0.47 μF. 716P series "Orange Drop". Notice that both dielectric and plate material are the same in both parts. IMO, that lowers the possibility of "smearing" that some folks claim to hear, when bypassed caps. are employed.
Film and foil parts this large are expensive. My preference is a 4.7 μF. metalized polypropylene (MKP) part bypassed by a 0.47 μF. 716P series "Orange Drop". Notice that both dielectric and plate material are the same in both parts. IMO, that lowers the possibility of "smearing" that some folks claim to hear, when bypassed caps. are employed.
I tend to drive things in parallel, so I went for 10uF. Cheap electrolytic. bypassed by 0.22uF MKP X2 safety capacitors... They sound fine and didn't cost a fortune.
If you don't want to use anything electrolytic, these will do splendidly. NEW 2pcs MKP-X2 10UF 275V AC,400VDC Capacitor for induction cooker #C1iR | eBay
If you don't want to use anything electrolytic, these will do splendidly. NEW 2pcs MKP-X2 10UF 275V AC,400VDC Capacitor for induction cooker #C1iR | eBay
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