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Looking for comments on Welborne Labs PS10 reg. HT supply

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#2
Unless you need it to outsurvive you, and nuclear war, I wouldn't bother with polyprop caps, unless you've got cash to burn.

Don't short the output.. the fet will smoke!
well, unless those resistors upstream limit current to a reasonable value.
 
#4
- So you don't think the polyprop's have any influence on the final sonics of the amp?
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It probably depends on the influence of the psu...
in a SET amp this would be pretty much the case, and though my own experience with pp caps in the psu is a spud headphone amp only (using the C3G), it was clearly audible...to the better.

A regulated supply is a different beast I can't comment on...sonic impact is likely lower so using pp caps would indeed be just an issue of longevity.
 
#5
I've been designing and building regulated supplies for my SET amplifiers for about 15yrs now and generally use PP or PPIO in my supplies. I tend to keep things long enough that electrolytics wear out, and with careful shopping non exotic motor runs or Solen polyprops can be acquired for little more money than a good electrolytic, and in some cases far less.

I too have observed a positive impact on the sound quality when using PP over electrolytics, although in good regulated designs the difference is pretty subtle.

Also you can fairly easily design and build your own regulated supplies instead of buying this kit.
 
#6
WE91 said:
Hello folks.

I plan on using the Welborne-labs PS10 (all polyprop.) regulated supply for a SE 300B output-stage ...

Does anyone have comments?
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Colt45 said:
Unless you need it to outsurvive you
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This particular supply is not likely to out-survive you a) because it has a tendency to become unstable and burn itself up, and b) because you are unlikely to get anything you buy from Welborne actually shipped to you.

That said, in a single ended design, unless you go to great lengths to prevent it, the power supply is part of the signal path. Polyprops make a big difference. Also, the schematic and parts list for that particular supply is attached to a thread somewhere around here -- search for it.
 
#7
Re: Re: Looking for comments on Welborne Labs PS10 reg. HT supply

his particular supply is not likely to out-survive you a) because it has a tendency to become unstable and burn itself up, and b) because you are unlikely to get anything you buy from Welborne actually shipped to you.
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lol :joker:

i have heard the same about those supplies, there is a thread somewhere with pics of the damage
 
#11
The circuit has a lot of issues....
There needs to be a slow-start to allow the heaters time to warm the tubes...possibly R4 and C7 could be of value to do this already...
There is no protection diodes accros the Q1 FET to protect it durring turn-off... Unless you use a real high voltage FET to prevent this problem....then the higher voltage FETS have lower gm , therefore the output impedance of the supply will not be that low...
Also the zener string is not protected and is susceptible to audio in the B+....need to use a PNP CCS to feed the zener string....

Chris
 
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