new broskie phono....

[dave dove]

hi chaps

as i am stupidly happy with my previous JRB phono
i thought i might ruin it all by building the attached...
seems straightforward enough?
anyone know where i could source the optxs?
brian sowter reckons i would not be able to drive an amp
due to varying output impedance????
and recommends something with no gain
which rather defeats the object really
JRB reckons 1:14 or thereabouts
i have everything else
a cheap and cheerful solution would be ideal
thoughts ideas and abuse welcome....

looking forward

dave

[Andrew]

Hi Dave,

Whatever your driving is going to be 14 squared (196) times harder to drive than it would be without the final step ups, and all from a 12AU7 at, well can't be more than a few mA, but then JB knows his stuff so perhaps I'm missing something obvious.

cheers,

-- Andrew

[Nick]

how about a little 115-0-115 : 7-7 toriod, 115:7 is 16:1

[dave dove]

thanks nick

just the kind of sensible answer i needed

dave

[JamesD]

this looks nice

I do wonder if the AU7 has enough wellie to drive the output - I would be tempted to try something with more drive for the output side...

Let us know how it goes!

James

[Andrew]

this looks nice

I do wonder if the AU7 has enough wellie to drive the output - I would be tempted to try something with more drive for the output side...

Let us know how it goes!

James

My point exactly, but better put. Dave what about the 6C45 you were playing with?

-- Andrew