Huh??
As I noted, Rudolf's I/V (same topology as Jocko, but with slightly different values) works just fine.
Speaking of this topology (Rudolf version) ... I concur that it works and sounds "clean".
HOWEVER, after some recent extensive listening (in a classic Philips multibit CDP), I must confess I prefer the stock Philips opamps (or other opamps). The opamps just sound more punchy and dynamic. The discrete I/V sounds compressed.
Huh?Hi,
QSerra gave a hint in #185 ..... saying that the common collectors of Q2and Q4 needed a dc path to a defined potential (a supply lin, gnd, etc).
As both collectors are high impedance it his highly improbable that a certain stable idle potential develops, but rather that the voltage is driven 'into' one of the collectors .... to a,most 0V or V+.
One could either omit with the current source Q4 and just use a load resistor connected from Q2s collector to V+, or use a current mirror mirrors into a gnd (or V-) referenced load resistor.
jauu
Calvin
As I noted, Rudolf's I/V (same topology as Jocko, but with slightly different values) works just fine.
Speaking of this topology (Rudolf version) ... I concur that it works and sounds "clean".
HOWEVER, after some recent extensive listening (in a classic Philips multibit CDP), I must confess I prefer the stock Philips opamps (or other opamps). The opamps just sound more punchy and dynamic. The discrete I/V sounds compressed.
Hi,
if, You refer to the circuit You linked in #195 it is just that decisive small difference QSerra and I talked about.
Rudolf´s circuit connected a resistor from the joint Collectors to gnd (R4, 1k5) --> stable DC-potential at the collectors.
The Jocko connected not a resistor but a cap to the Collecors ... the resistor follows behind the cap --> indifferent DC-potential at the Collectors.
jauu
Calvin
if, You refer to the circuit You linked in #195 it is just that decisive small difference QSerra and I talked about.
Rudolf´s circuit connected a resistor from the joint Collectors to gnd (R4, 1k5) --> stable DC-potential at the collectors.
The Jocko connected not a resistor but a cap to the Collecors ... the resistor follows behind the cap --> indifferent DC-potential at the Collectors.
jauu
Calvin
Page 1, OP
Built that one ages ago with ZM's precious help and it has been working in my CD Player ever since, gorgeous sounding.
There is a thread here somewhere discussing the whole process; changing Shanling CD-S100MKII IV .
Found it....: Upgrade output Shanling CD-S100 MkII
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