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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

Goldilocks & the 3 (or more) preamp power supplies

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I've not built nor bought much tube-wise for nearly 20 years but remember some subjective impressions of preamps.

LCLC with 100uF electrolytic/5K plate decouplers in a mod Dyna PAS = "soft" , quiet background - high level stage may had poor choice of FB resistor to meet its gain.

Precision Fidelity C7 stock had an IC chip for regulator feedback - sounded much better/ less "hardness" with zener reference TIP50 and 1st stage RC deoupler

B. Moore "New Venusian" - only heard it stock with beer can size electrolytics.

Theta - cap multiplier (I tend to like cap-multipliers

Mu-follower phono preamp - LM317T - maybe a bit solid state sounding when it shouldn't

some low current Dyna Pass circuits seemed to fare pretty well with RC filtering.

anyhow, at this point in time, do most builders figure in the power supply for their individual tastes? - or do they go more for specs and low output Z over a wide bandwidth?
 
not sure if I understand the 3rd reason but I'v sometimes just used up a set of chokes and whatever was laying around knowing there's enough ripple reduction before the Zener-referenced cap-multiplier but not thinking about the mix until it was built and high level stage changed a few times.

CLCLC (10H chokes) -> zerner ref. cap multiplier then resistor biased multipliers in PAS chassis = pile of parts - chokes were cheap, same with funky old electrolytic in the box.

An externally hosted image should be here but it was not working when we last tested it.


did choke input supplies with no active regulation fall to the wayside for phono preamps? how about LC decouplers within the preamp chassis? - (never had ripple low enough for that to work well)

what I'm trying to get at - do supplies sometimes get overly complex/bulky and perhaps worse sounding than they should? were some unregulated techniques more pleasing than some LM317 setups? does it take AB testing?
 
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