Octave V 50 MKII Owner's Manual - page 13
7. PHONO MM/MC OPTION
7.1. The role of the phono
A record player is an electro-mechanical device. Music signals are "pressed" into the grooves
in the record, and these are physically tracked and read by the pickup cartridge. In order to
get the entire 20 Hz - 20 KHz frequency range into the grooves, the frequency response has
to be shaped by lowering the level of the low frequency information and raising the level of the
high frequency information. This predefined equalization curve is known as RIAA equalization.
A phono amplifier must exactly equalize for RIAA recording characteristic if it is to avoid col-
ouring the sound. Equalization accuracy must be within 0.5 dB over the entire frequency
range, with channel matching of at least 0.1 dB.
7.2. Guidelines for connecting to the phono section
1. Turn the function switch
o on the front of the V 50 to the input IN 1 or IN 2, depending on
whether you want to connect a MM- or a MC-system.
IN 1 position MC: for real MC-systems, which have an output voltage
< 1 mV
IN 2 position MM: for moving-magnet-systems and MC-high-output-systems
2. Connect the cinch-circuits of the drive to the corresponding input IN 1 or IN 2 on the rear
panel of the V 50.
3. Connect the ground cable of the drive to the ground connection GND
n of the V 50 according
to the operating instructions of the pick-up arm/cable producer (the ground cable is usually a
black wire with FCA-cinch-plugs)
Î Depending on the pick-up arm-cable-wiring, there may be no additional ground
connection, as it may already be connected internally
Î Especially with MM-systems in connection with metal-pick-up-arms you have to
check, whether a ground connection is necessary or not
Explanation
Usually, the ground connection is connected to the pick-up arm or the head shell. This is nec-
essary to prevent hum-disturbances or broadcasting interferences. Therefore, in most cases
the ground connection is useful in order to stop these interferences.
However, some producers of MM-systems still connect the pick-up arm output with the chas-
sis, which means, they connect the pick-up arm with the conducting surface. This leads to
hum-disturbances caused by the double grounding of the ground cable. In this case, you have
to disconnect the carried ground cable. (Usually this is only the case with MM-systems)
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