aleph-x preamp question

While im busy with three pearls, they look nice i think, i startet thinking about a preamp that could fit to the alephx design from GRollins. I have some ideas how to get the "x" into a balanced preamp and as i think which idea is worth following and which is not, a question appeared. Is the X circuit able to convert unbalanced signal into balanced or must the converting be done the same way as in the classic aleph preamp design?

Nelson Pass

The one and only
Paid Member
2001-03-29 12:38 am
As long as the input diff pair is current sourced by a
high impedance, the circuit will happily convert a single
ended input to balanced output. Ground the unused input
with the same impedance as the source for the other.

Using it with SE output is another matter. You must also
ground the unused output or will you see the "open loop"
distortion characteristic of the circuit. This is because each
of the balanced outputs by themselves won't see the
correction, only the differential output is low distortion
and noise through the SuperSymmetric cancellation.
Aleph Ono for Alep-X

My friend Cucu built the Aleph X and he is very satisfied with the sound. (Thanks for Mr. Pass and Grey Rollins!!!)
Now he would like to build a preamp with very low output imp and more precise sound then the Aleph preamps with no negative feedback has.
He thought on the Aleph Ono phase shifter circuit as starting point.
His question: need he change anything in the attached schematic?


Tyimo and Cucu:)


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