Chapter 1 - Introduction
Phædrus Audio's
Groove
Sleuth Mk.II
preamplifier
is designed to be used in
conjunction with Pspatial
Audio’s
Stereo
Lab
(Phonograph
or
Audiophile) app which
runs under OS X on the
Apple Mac.
Stereo Lab
has
a wide feature set but it devotes a large part of its
functionality to software equalisation and
decoding of analogue records.
This isn't just technology for technology's sake.
There are real, audible reasons for doing this:
phase-linear warp and rumble filtering is only
possible in the digital domain and reveals a bottom
octave with unprecedented clarity and realism.
The accuracy of RIAA equalisation and perfect
channel balance ensures an uncoloured sound
with superb stereo sound staging. And the
flexibility in recording characteristics will bring to
life LPs you thought mediocre. Moreover,
Stereo
Lab
also includes software decoders for
QS
and
SQ
quadraphonic and
Ambisonic
LPs; thereby bringing
life to forgotten, analogue, multichannel gems.
For
Stereo Lab
to process needle-drop captures
and equalise them, it needs recorded files of the
"raw" signal, direct from the groove, unfettered by
analogue equalisation. And that is where the
Groove Sleuth Mk.II
preamplifier comes in. It is a
phono preamplifier of the very highest quality but
without
equalisation, so that the signal fed to the
computer is the closest version of the signal direct
from the groove, but at a suitable amplitude for
digitisation. The
Groove Sleuth Mk.II
preamplifier
has various options to augment this basic task to
aid with monitoring and to ease integrating these
units into a high-quality audio system. These are
described in the pages that follow.
Chapter 2 - Safety
General
Before
using
any
piece
of
equipment
manufactured by Phædrus Audio, be sure carefully
to read the applicable items of these operating
instructions and the safety suggestions. Keep them
for future reference. Follow the warnings indicated
on the unit, as well as in these operating
instructions.
THE USER SHOULD NOT ATTEMPT TO SERVICE THE
UNIT. ALL SERVICING SHOULD BE REFERRED TO
QUALIFIED SERVICE PERSONNEL OR FACTORY
ONLY.
Phædrus Audio products should NEVER be
connected to the external power supply or in any
other way energised when the case is opened
and/or the circuit boards are accessible.
General Safety Instructions
Do not operate this equipment near any
source of water or in excessively moist
environments.
Keep this equipment away from babies,
children and pets.
Do not let objects do not fall, or liquids be
spilled, onto the enclosure.
Situate this equipment away from heat
sources or other equipment that produce
heat.
Ensure this equipment has adequate
ventilation. Improper ventilation will
cause overheating, and can damage the
equipment.
When cleaning this equipment, remove
all connections to the unit; including
power and gently wipe with a clean lint-
free cloth; if necessary, gently moistened
with lukewarm or distilled water. Use a
dry lint-free cloth to remove any
remaining moisture. NEVER use aerosol
sprays, solvents, or abrasives on this
equipment.
This equipment should be serviced by
qualified service personnel or returned to
Phædrus Audio when: an object (or
objects) have fallen into the enclosure; or
liquid has fallen into, or been spilled into
the unit; or the unit has been exposed to
rain or high humidity; or the unit does not
operate normally or exhibits a marked
change in performance; or the unit has
been dropped, or the enclosure has been
damaged.
Chapter 3 - Gramophone record
equalisation in software
The signal recovered from a gramophone
(phonograph) record via an electrodynamic pickup
(moving-coil or moving-magnet type) has the bass
drastically attenuated and the treble boosted.
Replay processing is therefore required to present
a complimentary characteristic to restore the
