I want to upgrade the coupling caps in my Chinese Blue Velvet preamp. They are 0.68uf. Considered Miflex but they a quite big as well as Jupiter wax.
V-Cap ODAM are a good size and price but the nearest higher value they offer is 1uf.
Would it be ok to substitue a 0.68uf for a 1uf?
V-Cap ODAM are a good size and price but the nearest higher value they offer is 1uf.
Would it be ok to substitue a 0.68uf for a 1uf?
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I’m not sure how much benefit you will hear but, without looking at the time constants there could be some consequences.
C2 is worthy of attention because the bass performance (lower cut off frequency and hence phase shift in the audible region) depends on the input impedance of the circuit your output is driving. A larger cap is better and although 1uF is already good you can go larger, especially if driving a solid state amplifier which typically has a lower input impedance than a valve amp. You should also add a high value resistor (e.g. 1Meg) from the output to ground to prevent C2 charging up from static.
C2 is worthy of attention because the bass performance (lower cut off frequency and hence phase shift in the audible region) depends on the input impedance of the circuit your output is driving. A larger cap is better and although 1uF is already good you can go larger, especially if driving a solid state amplifier which typically has a lower input impedance than a valve amp. You should also add a high value resistor (e.g. 1Meg) from the output to ground to prevent C2 charging up from static.
I would not change the value of C1 but C2 could be larger without penalty, IMO. In fact I would routinely use a 1uF cap or larger at the output of a preamp. You might consider Audyn Coppers. A wonderful cap and more reasonably sized than Miflex--and more expensive too, of course.
I don't know the input impedence of my amps but they are 8w 300b monoblocks.
I will go for the 1uf ODAMs in the C2 position and go for the Audyn Copper 0.68 in C1 I think.
I opened up the preamp to see the clearance. No way those Miflex are fitting in there!
I'm very new to this so thanks guys for the info much appreciated.
I will go for the 1uf ODAMs in the C2 position and go for the Audyn Copper 0.68 in C1 I think.
I opened up the preamp to see the clearance. No way those Miflex are fitting in there!
I'm very new to this so thanks guys for the info much appreciated.
One more question......
The R2 resistor. 200r. Could I change that to a 180 or 220? What would be the effect?
The reason is I want to get some nice resistors (for my own tweaking curiosity) and can't find any well spoken about ones at that value.
The R2 resistor. 200r. Could I change that to a 180 or 220? What would be the effect?
The reason is I want to get some nice resistors (for my own tweaking curiosity) and can't find any well spoken about ones at that value.