van den Hul The Grail SX, Руководство пользователя

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Impedance matching for MM and MI systems connected to the “MM” input
These lines are dedicated to the skilled users only – if in doubt, always consult your dealer!
What about the impedance matching of MM or MI systems? Normally, everything should be
fine. “The Grail's” input impedance is 47Kilo-Ohms (47000 Ohms), this is the standardized
value for MM/MI cartridge inputs. Just connect your cartridge and enjoy the music!
In very few cases the the input capacitance of the combination “ turntable signal cable +
preamplifier input ” is not high enough. As mentioned, this is rather uncommon. Normally the
input capacitance is just right or even slightly too high (if way too high, use a better and
shorter cable, ask your dealer!) But in case the input capacitance is to low, you may get an
aggressive and too “bright” sound.
Remedy:
You can do the same as with the matching of the high output MC system – but this time you
use no resistors but instead high-quality(
! ) capacitors like Polystyrene type capacitors and
solder them into the connectors, just as described before. Reasonable capacitor values may
vary from 47pF up to 330pF (“pF” means “pico Farad” = 10
-12 F). Always start with the small
values (47pF) and then listen to it for screening. If not satisfying, take the next higher value
(e.g. 100pF) and again listen to it. If even an additional 330pF will not bring the desired
results, take a look at the cartridge installation: is it proper mounted under your tonearm?
Check the alignment of the cartridge with a good alignment protractor. Also check the tracking
force, stick to the cartridge manufacturers recommendation for your cartridge.
Hint: keep in mind that your cable has an inherently capacity and the input of “The Grail” has
also a 50pF input capacitance. So you only have to add the missing part of the recommended
total capacitance, given by the cartridge manufacturer.
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The heart of “The Grail”: the “ Coils-Only” deemphasis network
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van den Hul
®
Phonograph Preamplifier „The Grail SX“ 9