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beefy choke -- please help

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i have been looking at a schematic on diyaudioprojects.com, it is a slight modification of mikaels kt88 se amp which has had much press on this site.

however one of the mods that has been done to it is the addition of a 5H choke to the pre-amp power line. he says

"Also, the power supply to the 6N1P preamplifier section has been beefed up with the addition of a choke"

could someone explain this beefing up ,,, benifits etc
]
cheers
soundbadger

the link below shows the schematic
schematic
 
The addition of a choke - where before there was none - will likely improve the sound of the preamp. This is because the resistor it replaces has a constant impedance across the frequency range where as the choke has a much higher impedance at high frequencies. Since the most damage is done by high frequency crud bleeding into the audio circuit, the improved filtering of that crud is of benefit to the overall sound.
Things like improved low level detail, blacker background, smoother highs and other hi-fi superlatives spring to mind.

I have gotten to the stage where a choke is an essential of any of my power supply designs for exactly this reason. This even applies if the choke is doing little to attenuate mains hum.

Shoog
 
soundbadger said:
the choke in this situation isnt replacing the plate resistor its additional,, check the schematic.
cheers though

Yes, the choke is, as stated, part of the power supply. The plate load resistor is just that ... the plate load. The choke and the 10uf cap are not part of the plate load. Thus the previous poster's comments about the benefits of chokes in the power supply. - Pat
 
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