Go black or go around?

[Salas]

I have some Silmic 1000 μF cathode bypass caps installed in my 6V6 preamp. The tone and body is awesome from that unit, but since the Devil will find work for idle hands to do, I wonder if it will benefit from Black Gate N (red non polars) or it will be better to bypass the Silmics with a couple of SCR Teflon blue ($$$) 0,47 μF caps that I have. Opinions?

[dsavitsk]

My experience is that the Blackgates are better than the Silmics, but how about biasing with red LED's instead, or fixed battery bias using the teflons as input couplers?

[Salas]

Hmmm... adding yet another coupling to the circuit, defies the point of a better cathode sound....doesn't it? Also achieving 15V that I need there, calls for a rather long string of LEDS. Will they work as well as a couple that the norm is? In what way you prefer Black Gates soundwise? More palpable and energetic than the Silmic? Do you ever bypass with small film caps? They can add constructively on cathode bypass caps. Any experience on that?

[dsavitsk]

What I meant was that if you bias the grid with a battery and connect the cathode to ground, then you have gotten rid of the cathode cap. But, you will need an input coupling cap as the grid will be at -15 w/r/t/ ground. The upside is that you trade an electrolytic in the signal path for a small teflon in the signal path -- and, since the input impedance is large, you can probably use a much smaller cap that the 470n.

For a string of LEDs, see SY's red light district amp.

Blackgates are, in my experience, more detailed and less flat sounding. Truthfully, I like the Cerafines a lot more than the Silmics, too. Bypassing sometimes works well, sometimes doesn't, and my experience there is that it can be really unpredictable. But, if you have the caps, give them a try.