Use 50k pot max if you can to can drive Ri with decent bandwidth. Says up to 50k pot on the schematic notes.
Put 1meg resistor across the input when with no pot just for having a reference to ground when disconnected from a source.
55k AC impedance again regarding path of signal to the grid because of shunt feedback network
Perfect thanks, it's just to know if the coupling output capacitor is properly rated at noDac.
RLo not only drains Cout when off to avoid reconnection pops. It also provides last resort DC reference in the NFB version. But its good practice to further brace with a Meg resistor across the input when there's no volume pot there. Without DC reference the circuit simply does not know how to bias up correctly.
1st impressions are positive & very good SQ, as you said strong bass but articulated and clean, the mids aren't thin but not excessively thicks, about the highs mine opinion can't count (I'am an old 65 years man). I guess the combo pasive load + NFB makes the sound cleaner and not soft in this case complements one to the each other, normally all pasive loads I tried in several configurations sounded very natural but soft without punch (always without NFB) so always sounded far better the active load: more cleaner with punch (dynamics) and for mine experience with NFB of course the opposite weak bass & mids but very clean with more dynamics.
Really really you make a simple & not expensive and very good piece of cake to enjoy audio at very high sound quality level, congrats Salas you can be proud of your work & have no words to express all my gratitude.
Cheers
Felipe
Really really you make a simple & not expensive and very good piece of cake to enjoy audio at very high sound quality level, congrats Salas you can be proud of your work & have no words to express all my gratitude.
Cheers
Felipe
Comparing vs 12B4 used recently I feel more power, 12B4 output cap used Stealth 10uF 310V is better than in 6V6 used the 4.7uF Auricap 450V.
Without 1R and 47uF RC for separate channels after SSHV2 the soundstage open a lot, what increase a lot the power in that way that I believed I desoldered de NFB in both channels taking off the RC. The negative side is with RC was a little bit of hum but weak & supportable but without RC it's unbearable doe to the increase of power.
Time to do measurements. I will keep you updated.
Time to do measurements. I will keep you updated.
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Another thing about the hum, I guess is related that PSU is operating at the limit to give the 330VDC required but not got.
SSHV2
Vin 322.24V
Vout 318.85V
AC ripple 2.2mV~
Gotcha, SSHV2 need 20V of headroom to operate well!!!
Vin 322.24V
Vout 318.85V
AC ripple 2.2mV~
Gotcha, SSHV2 need 20V of headroom to operate well!!!