Konnichiwa,
You may assume what you wish.
The facts are that irregardless of layout there is capacitive and inductive leakage out of ANY mains transformer into the chassis. With nice choppy waveforms from low impedance, capacitor input rectification you get quite a nice spray of junk. It has to go somewhere and thus usually forms bwtween the various interconnected pieces of equipment all sorts of interesting noiseloops, with various rectification effects at various plugs and so on.
Again, this is entierly independent from any layout and strictly related to electrical safety codes and the use of mains power in Audio gear.
Sayonara
anatech said:
You may assume what you wish.
The facts are that irregardless of layout there is capacitive and inductive leakage out of ANY mains transformer into the chassis. With nice choppy waveforms from low impedance, capacitor input rectification you get quite a nice spray of junk. It has to go somewhere and thus usually forms bwtween the various interconnected pieces of equipment all sorts of interesting noiseloops, with various rectification effects at various plugs and so on.
Again, this is entierly independent from any layout and strictly related to electrical safety codes and the use of mains power in Audio gear.
Sayonara
Okay,
Sigh .... That's why the use of resistance reducing the HF component of current and induced voltage is beneficial. If a SS and tube supply have the same characteristics, they behave in a similar way. Circulating ground currents may have some effect - but you can't pin them on anything since there are sooo many variables. Like the guy next door or ground return current form industry. I refuse to run my gear on batteries and am happy ith the lack of noise. Not to mention the ambient acoustic noise would certianly mask anything at your levels.
-Chris
Sigh .... That's why the use of resistance reducing the HF component of current and induced voltage is beneficial. If a SS and tube supply have the same characteristics, they behave in a similar way. Circulating ground currents may have some effect - but you can't pin them on anything since there are sooo many variables. Like the guy next door or ground return current form industry. I refuse to run my gear on batteries and am happy ith the lack of noise. Not to mention the ambient acoustic noise would certianly mask anything at your levels.
-Chris
"Snubberizing"? 
After reading Olsen's experiences with rectifiers I tried a small air coil inductor in series with the current limiting resistor between an 5ar4 and a 'snub'd' oil cap, values derived from a Spice analysis. The coil just happened to be a junkbox part of unknown value. It made a nonsensical degree of improvement from the mids up. Dropping a calculated value for inductance into Spice suggests approx 25 db better PS rejection in this particular circuit from about the AM band up to FM. The coil came from an old AM tower phase monitor and is under 5 uH, it was designed to operate at HF.
This is definitely an area worth investigating!
After reading Olsen's experiences with rectifiers I tried a small air coil inductor in series with the current limiting resistor between an 5ar4 and a 'snub'd' oil cap, values derived from a Spice analysis. The coil just happened to be a junkbox part of unknown value. It made a nonsensical degree of improvement from the mids up. Dropping a calculated value for inductance into Spice suggests approx 25 db better PS rejection in this particular circuit from about the AM band up to FM. The coil came from an old AM tower phase monitor and is under 5 uH, it was designed to operate at HF.
This is definitely an area worth investigating!
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