Violectric PPA V600, User Manual

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20
OPENING THE UNIT
In order to change any DIP switch or jumper settings inside the PPA
V600, its case must be opened. For this purpose, a TORX screwdriver
T10 is required, and you should - by all means -
PULL THE MAINS PLUG !!!
after which any setting procedures can be effected without risk.
Disassembly
1. remove the two upper screws on the front panel
2. loosen the two lower screws on the front panel by 2 to 3 turns
3. remove the two upper screws on the rear panel
4. lift off the lid to gain access to the switches/jumpers
5. reassemble the unit in reverse order.
Things to know…
Why are turntables susceptible to hum ?
Most turntables are connected unbalanced via cinch leads. Unfortunately
indeed, since a balanced connection would be hum-free in practice and much
more advisable in technical terms. Common pickup systems usually represent a
perfect dipole, and thus the advantages of balanced signal connection could
easily be made use of.
Moreover, vinyl recordings are being equalized during the production process,
i.e. low frequencies are reduced and high frequencies boosted. During playback,
the equalizing preamplifier inverts this process, thus enhancing not only the low
frequency range, but also any hum interference to the signal lead.
When connecting the pickup in balanced mode, hum interference as would be
unavoidable with unbalanced leads is significantly reduced.