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previous: andyfuchs I would doubt the heaters have any ... -- 4/22/2000 10:27 PM

Re: Scott Heaters for PA Cathode Resistors

4/22/2000 10:55 PM
Ray Ivers	Re: Scott Heaters for PA Cathode Resistors Andy, Thanks again for the power supply info. If I can get 'em, I'll use em! I think Old Colony carries the Velleman stuff, if I'm not mistaken. I thought I read somewhere that the highest DC voltage in a series DC heater string should be on the first tube - kind of along the lines of that 'bias the heater center-tap with DC' thing that I never had much luck with. When heater strings were series connected and AC-powered, in the really BAD old days, the first tube would be grounded, I believe. It may well not make any difference whatsoever with the DC string. All this interest in regulation is sparked by my new-found interest in the elimination of 'ghost notes'. I'm starting to realize that every amp I own has them to varying degrees (even the dead-silent ones, at low volumes!), and I'm starting to think that every amp I've ever played through has had them, and I'm about ready to run an amp off batteries to find out! I guess any amp is just a power-supply modulator, and every non-regulated amp is modulating 60 Hz + 120 Hz + harmonics to some extent; maybe I'm just hyper-sensitive to this (strange, because my ears seem quite average to me in every other way). I'm on a mission! Thanks again for the info. Ray

4/22/2000 10:55 PM

Ray Ivers

Re: Scott Heaters for PA Cathode Resistors

Andy,

Thanks again for the power supply info. If I can get 'em, I'll use em! I think Old Colony carries the Velleman stuff, if I'm not mistaken.

I thought I read somewhere that the highest DC voltage in a series DC heater string should be on the first tube - kind of along the lines of that 'bias the heater center-tap with DC' thing that I never had much luck with. When heater strings were series connected and AC-powered, in the really BAD old days, the first tube would be grounded, I believe. It may well not make any difference whatsoever with the DC string.

All this interest in regulation is sparked by my new-found interest in the elimination of 'ghost notes'. I'm starting to realize that every amp I own has them to varying degrees (even the dead-silent ones, at low volumes!), and I'm starting to think that every amp I've ever played through has had them, and I'm about ready to run an amp off batteries to find out!

I guess any amp is just a power-supply modulator, and every non-regulated amp is modulating 60 Hz + 120 Hz + harmonics to some extent; maybe I'm just hyper-sensitive to this (strange, because my ears seem quite average to me in every other way). I'm on a mission!

Thanks again for the info.

Ray

Replies:

Ken Gilbert ray, something else to keep in mind... -- 4/23/2000 12:30 AM