Millennia LPE-2 Analog Legacy Phonographic / Archiving Preamplifier - Manual (Page 10)

10
LPE-2
EQUALIZER / FILTER SECTION
(6) BAND IN/OUT SWITCH "IN"
Pushbutton switch which places its associated EQ band in circuit or out of circuit. There are
eight bands of equalization on the LPE-2 Analog Legacy. Four bands provide precise phono
compensation, including RIAA and an unlimited number of legacy curves. Four additional
bands (marked "FILTER") provide additional sculpting and repair tools. An EQ band is in-
circuit when its associated band switch is depressed and LED is illuminated. Band In/Out
switches are provided both for comparing a single EQ band setting versus flat-band response,
and for bypassing any band entirely, such as with flat acoustic recordings.
(7) FREQUENCY SELECT ROTARY SWITCH
Six position rotary switch (Grayhill, gold contacts, military spec) which selects fixed high and
low band frequency points. LF compensation frequencies are preset to 200, 250, 300, 400,
500/RIAA, and 700/USER (in Hz). HF compensation frequencies are preset at 10 kHz to -5.0,
-7.0, -9.5, -11.5, -13.7/RIAA, and -16.0/USER (in dB). Where a switch is marked "USER", the
user may change the value of a fixed capacitor to allow for virtually any compensation frequen-
cies not preset on the factory stock rotary switch points. See printed circuit board diagram on
page 12 for capacitor socket location (C14 on LF board and C8 on HF board).
The LPE-2 compensation and filter circuits are based upon a unique shunt topology. This
topology is unlike conventional "state variable" filters in that only one signal path amplifier is
employed. Compare this with conventional filter designs employing upwards of four to seven
signal path amplifiers. Fewer amplifiers means greatly improved sonic integrity.
LF filter points are preset to 20, 35, 60, 100, 180, and 260 Hertz. High frequency filter points
are preset to 1, 2, 3, 5, 8, and 12 kHz. A rear panel switch facillitates bypass of the entire
Filter Section if not required, thus bypassing one active stage of EQ amplification for improved
sonic performance. See Rear Panel diagram on page 7.
(8) PEAK/SHELF SELECT SWITCH
Pushbutton switch which selects LF and HF filter curve shape. When switch is depressed and
LED is illuminated, EQ is shelving at 6 dB per octave. When switch is not depressed, EQ is
peaking with a fixed "Q" of 1.0 about the center frequency selected.
(9) BOOST/CUT CONTROL
Four conductive plastic rotary potentiometers (French Vishay) offering up to +10 dB of boost
and -10 dB of cut. Boost/Cut potentiometer has 21 detented positions for accurate repeatabil-
ity and session logging.
(10) POWER SWITCH "POWER"
Rocker switch for switching AC line power on and off.
(11) TEMPLATE
(not shown) A session logging template for use with the LPE-2 Analog Legacy is available for
download on the Millennia web site at: http://www.mil-media.com/LPE-2.html