User Guide

Chapter 13: Tools and Utilities
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against the inevitable vinyl pops, clicks, and surface noise. Pre-emphasis also prevents low frequency signals from
bouncing the stylus out of the groove.
When you play a record, the preamp's RIAA de-emphasis will reverse the EQ. High frequencies are cut, and low
frequencies are boosted. If you do not apply RIAA de-emphasis, either with a phono preamp or in the software,
vinyl will sound too bright and shallow.
HF Boost
If you recorded the disc with a mixer which has high-impedance inputs (preferably 1 MegOhm or better), set HF
Boost to zero, for “pure” RIAA de-emphasis.
Most audio mixer instrument/line inputs have impedance in the 10 KOhm to 100 KOhm range. A turntable's
magnetic cartridge will be “loaded” by the lower-than-expected mixer impedance. This won't damage the turntable,
but will affect the frequency balance. A 10 KOhm mixer input could cut the highs quite a bit, and even a 100 KOhm
mixer input could cut the highs a perceptible amount.
There is no way to predict the characteristics of your turntable cartridge and the input impedance of your mixer.
Adjust HF Boost by ear until the frequency balance sounds right. You may not get the frequency response as
precisely as the mastering engineer intended, but if you are happy with the result, who cares?
Some PG Vinyl Tool options can cut highs. If a record is damaged so much that subsequent PG Vinyl Tools cut
high frequencies along with the noise, you could increase the HF Boost by ear, to make up the loss.
Rumble Filter Checkbox
Cheap or worn-out turntable platters can make subsonic vibrations. Slightly warped records can also make
undesirable low-frequency noise. Use the Rumble Filter to block unwanted low frequencies.
The Rumble Filter is a 24 dB per Octave Butterworth High Pass filter, which attenuates undesirable low frequencies.
In most situations, it will do no harm to always enable the Rumble Filter.
Rumble Filter Frequency
At the default of 40 Hz, signals below 40 Hz are attenuated, and signals above 40 Hz are unaffected.
Vinyl mastering engineers typically avoided frequencies lower than 40 Hz. It is difficult to make vinyl cleanly
reproduce very low frequencies. Also, most consumers, even audiophiles with expensive stereos, did not have
speakers capable of reproducing lower than 40 Hz.
Unless you are dubbing classical organ records, it is doubtful that there is anything of interest below 30 or 40 Hz.
While adjusting PG Vinyl Tool, you can experimentally toggle the Rumble Filter on/off to make sure the filter is not
removing important audio features.
DeCrackle Checkbox
Enable the DeCrackle section. PG Vinyl Tool defines crackle as high frequency defects in the range of 2000 Hz to
20,000 Hz.
A single microscopic speck of dust, or a tiny static discharge, can cause an isolated “tick” which is too short to be
considered a “click.” The DeCrackle section removes these isolated ticks. Crackle is a cluster of high-frequency
ticks. If there are multiple close-spaced ticks, the ticks are perceived as a crackling sound.
First disable the DeClick Checkbox, and adjust DeCrackle. On a clean record in good condition, DeCrackle may be
the only necessary section. Normally you would only enable the DeClick section if DeCrackle can't adequately
clean up the mess.
DeCrackle Amount
This adjusts the sensitivity of what PG Vinyl Tool considers to be a tick/crackle. At zero, nothing is removed. As
the DeCrackle Amount is increased, PG Vinyl Tool will mute additional “tick suspects.” If the control is set too
extreme, PG Vinyl Tool will partially mute musical features, such as hand percussion or high-hat notes. Only set
the control high enough to remove ticks and crackles. If longer clicks remain, enable the DeClick section for
additional cleaning.
DeCrackle Activity
This displays the percentage of audio which is muted. Except for very worn records, adjust the DeCrackle Amount
so that the DeCrackle Activity reads no higher than a few percent. On very good discs, one might get “perfect”
results with less than one percent of DeCrackle Activity. Strive to mute only the minimum necessary to clean your
record.