18
Special functions
Please note:
In the following, the internal settings of the HPA V200 are discussed.
For changing these, a TORX T10 screwdriver is required and you
should by all means
PULL THE MAINS PLUG !!!
Only thereafter the settings can be altered without any hazard.
Frequency bandwidth limiting
Your HPA V200's upper frequency limit is 200 kHz - the so-called "3-dB
point" - at which signal level drops by 3dB. This limit is high enough to
exclude any effect on the audible spectrum on the one hand, but low
enough to provide sufficient rejection of possible radio-frequency
interference.
Towards the low end, your HPA V200's frequency response is not
restricted at all. This means that even extremely low frequencies - right
down to DC - will be amplified. "DC-coupling" as this technique is called,
is not necessarily useful since neither DC nor very low frequencies are
audible, but may damage your headphones on the other hand.
Therefore, the HPA V200 offers a low-frequency limiting option as well.
For this purpose, the two “LO-CUT“ jumpers to the left and right of the
"VOLUME" control can be swapped from “DC“ to “AC“ position. When
set to "AC", low frequency response is limited to 12Hz, again referred to
the "3-dB point".
See also: technical appendix, page 26.
Ex-works, the HPA V200 is set to "AC" response (12Hz).
