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Oliver Acoustic Research AR-94 specifications
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Here is the Schematic of Francesca. Francesca can be considered a intermediate step from "Francy" to "Francesca 99". With respect to Francy a interstage transformer is used to drive the 572-10 with very good improvements in output power and "quickness" of sound.

Audio project

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The 5842 can be changed with a parallel of EC97 (following the input section of Francesca 99). In this manner more amplification can be obtained and the sound is more "open" expecially in the high section. Distortion raises a little. Here is a photo of this prototype:

Rear Side: The "military looking" green boxes in the rear part of the photo are paper/oil 6uf/1000V capacitors on top of supply trasformers.

Front side: The black transformers are respectively: on top side the Bartolucci intertsage trasformer, and (bottom) the "lowther club Mediterraneo" double C core OPT. The little black thasformer on the left side of the tubes is the 30H double C core inductor. The brown box between the tubes is the paper/oil 1uF cap.

You can also see a spare noval tube socket between the tubes for srpp prototyping and several trimmers/pot for the bias point fixing or hum reduction. The red electrolitic cap are the ELNA's low-z, low distortion caps. used for cathode biasing of 5842 and 2A3.

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