X-BOSOZ power supply

[wuffwaff]

Hi,

I´ve almost finished the metalwork for my combined Perpetual Technologies P1-A / P3-A with X-BOSOZ output.
Since I will build the output stage using a X-BOSOZ with current source (like in Henriks shematic) I´m not shure if it is really neccessary to use a regulated supply.

As far as I can see the bias is set by the current source and won´t change if the dc voltage goes up or down a bit (by changes in the 230VAC line voltage). It will make the supply a bit simpler without the fets and zeners.

With the tranny I´m using I will get around +45, -28 volts DC with a C-R-C-R-C setup. I know this will waste a bit of power in the current source but it is a nice transformer (shielded and everything).

Does anybody see a problem with the usage of an unregulated (C-R-C-R-C) power supply instead of the regulated one?

William

[eLarson]

I tried it without the stack o' zeners + source follower, but always had some residual crud in the background. Things got much quieter when I used the voltage stabilizer.

(edit: I should add that my raw supply consisted of a set of HEXFREDS for the bridges, a 1.5H (56-ohm ESR) choke from Hammond, and a 10,000 uF ELNA Cerafine cap. I'd have thought that would have been good enough. Then again, I was running an unbalanced output. Maybe that would have turned the tide?)

YMMV, of course. You could also leave a bit of room inside to add a regulator board next to your output circuit if it isn't as quiet as you'd like.