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Phil Allison Phil Allison is offline
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Default Phono amp: why tie the cathode to the output?


"choobs"

It's an old Magnavox phono amp. Stereo using one 6EU7 (twin triode)
and 2 6BQ5's. The speaker outputs are Left, Right, and a Common
connection. The cathodes of both 6EU7 sections are tied to the
respective speaker outputs through a resistor with capacitor bypass
and one 6k8 resistor. The Blue OT wire hooks up at the speaker output
also, of course.



** I take it the OTs are attached to the speakers ?


Why connect things this way? Is it part of the RIAA
equalization? Feedback?



** Negative feedback, all right.

Also, the screen B+ is connected to the 6EU7 cathode pins.



** No way by a direct connection.


Can someone shed some light on any of this? I'd like to
change a few things and drive it with a portable cd player if that's
possible. Thank you.



** Hope the old heap of **** has an AC power transformer ???

Be lethal without one.





........ Phil