I connect the shield to the signal "cold" point (I always use two conductor -hot and cold wire- interstage) only on the signal source side.
Some recommendation suggest to connect shield to the safety ground/chassis, but for me the former solution is better. The signal cold point mostly connected to the ground/chassis with Ground Loop Breaker / Safety Loop Breaker.
In my quest for finding the optimal output capacitors for my gyrator loaded 26 preamp, I've been trying out russian K75-10 capacitors. And by the way they are GREAT! FABULOUS! INCREDIBLE! I'm lost for superlatives. I've tried them before in other setups without giving them too much attention, but in the output of Ales gyrators they just click like nothing have clicked before. I don't know if it is the large voltage swings or the low impedance but they are truly excellent. I really wanted my expensive teflons and my paper oils to be better but they aren't even close. The K75-10 doesn't have the best bass or treble but the large engulfing 3-dimensional midrange and the musicality is up there with the best I've ever heard. For heaven sake try them if you are experiencing that you play just a few selected recordings all the time or you sometimes feel that your setup is a little bit sterile, flat, boring or cool sounding. Trust me on this one. Try them.
I don't know the cut-off but in my case I have a 100K input impedance on the following amplifier stage.
Yes, you probably need a bit more Farads than me, but aren't you using a transformer based volume control after your preamp? Isn't the input impedance of your power amp reflected back through the transformers with some kind of ratio so that your preamp "sees" something completely different than 33K?
Yes, you probably need a bit more Farads than me, but aren't you using a transformer based volume control after your preamp? Isn't the input impedance of your power amp reflected back through the transformers with some kind of ratio so that your preamp "sees" something completely different than 33K?
I've opened up a couple of K75-10's. They are just metalized polyester caps. No paper except a little bit between the steel can and the polyester. It's quite interesting that polyester caps can be so musically rewarding. It seems that there isn't any technical explanation for it. I think Audio Note and Kondo in Japan may be on to something with the use of Mylar in their capacitors.
Thank you for making the calculations for me.
Thank you for making the calculations for me.
Using my cheap Chinese meter, the ESR of a K75-10 was startlingly high. I have no idea of the test frequency though. I will probably give them a try at some point.
V, and try to by pass your out put cap with a 0.033uF 1600V cap of the same kind.....and let me know please, if you are pleased !!!