Lou, of course... I'm now versed in EQ techniques... thanks to this list,
among others. Sorry if I gave a wrong impression.
I was only recalling the days when I knew but anything about the issue...
but I already noticed the audible difference between records played thru
RIAA amp (a standard phonograph from house audio equipment) and those which
had been previously taped, taking the signal directly from the ceramic cart
into the tape recorder pre-amp. When tapes were then replayed, simply the
RIAA was not there, and that's why 78s sounded much more natural. Ceramic
carts must have eq curves which are suitable for 78s, and the RIAA
correction is not applied in this process.

Saludos,

Inigo