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previous: Doc ".....supposedly done with no load ... -- 1/26/1998 2:13 PM

Re: Right bias for JCM 800?

1/26/1998 3:02 PM
GVB	Re: Right bias for JCM 800? Exactly, this is what I was taught, but it doesn't make sense to me as far a theory is concerned. At 0Hz/DC regardless of a resistive or reactive load in the secondary, there should be no power transfer, no stress on the primary or secondary, and the impedance "reflected" by the secondary will be infinite and make no difference on the primary. I suppose that if you change the direction of the current (i.e. raising the bias voltage and then lowering it) would cause the power to be transferred to the secondary. The only thing I'm not sure of, is the point when having too high an impedance on the secondary becomes a problem. For instance with speakers, it is not a problem to use a higher impedance speaker than specified by the OT taps. But at what point will "damage" occur to the OT? Can anyone enlighten me on this? GVB

1/26/1998 3:02 PM

GVB

Re: Right bias for JCM 800?

Exactly, this is what I was taught, but it doesn't make sense to me as far a theory is concerned. At 0Hz/DC regardless of a resistive or reactive load in the secondary, there should be no power transfer, no stress on the primary or secondary, and the impedance "reflected" by the secondary will be infinite and make no difference on the primary. I suppose that if you change the direction of the current (i.e. raising the bias voltage and then lowering it) would cause the power to be transferred to the secondary.

The only thing I'm not sure of, is the point when having too high an impedance on the secondary becomes a problem. For instance with speakers, it is not a problem to use a higher impedance speaker than specified by the OT taps. But at what point will "damage" occur to the OT? Can anyone enlighten me on this?

GVB

Replies:

J Fletcher Well here's some info gleaned from ... -- 1/27/1998 7:08 AM