Smyth Research Realiser A8, Руководство пользователя

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Bass redirection
The lowest octaves of the main channels are often redirected to the subwoofer. This is done when it is
believed that the subwoofer will do a better job reproducing the low frequencies than the main
speakers will, which is almost always the case. This bass from the main channels is combined with the
LFE channel and the sum is sent to the subwoofer. The correct level relationship between LFE and
main channels (+10 inband gain on the LFE) must be established before the summing; it cannot be
adjusted later.
In cinemas, bass redirection is not widely deployed, though there is cinema equipment to do it.
In studios, bass redirection is often absent. The reason usually given is that the engineers want to hear
what they assign to the main and LFE channels separately. Redirection is sometimes installed that can
be switched in and out so that the engineers can hear how their material will sound on bass-managed
home systems.
In the home, bass redirection is usually advisable, but may or may not be engaged.
Like LFE gain, bass redirection can occur upstream or downstream in both the measured and playback
systems. Here is a table which adds to the previous table, considering both.
Measured system Playback system LFE at Realiser input PRIR SW SW REL VOL Redirection in phones
LFE gain upstream LFE gain upstream +10 0 0 none
LFE gain upstream LFE gain downstream 0 0 +10 none
LFE gain upstream LFE gain + LF redirection upstream +10 0 0 added
LFE gain upstream LFE gain + LF redirection downstream 0 0 +10 none
LFE gain downstream LFE gain upstream +10 +10 -10 none
LFE gain downstream LFE gain downstream 0 +10 0 none
LFE gain downstream LFE gain + LF redirection upstream +10 +10 -10 added
LFE gain downstream LFE gain + LF redirection downstream 0 +10 0 none
LFE gain + LF redirection upstream LFE gain upstream +10 0 0
lost; could add with
preamplifier or Realiser
LFE gain + LF redirection upstream LFE gain downstream 0 0 +10
lost;
could add with Realiser
LFE gain + LF redirection upstream LFE gain + LF redirection upstream +10 0 0 substituted
LFE gain + LF redirection upstream LFE gain + LF redirection downstream 0 0 +10
lost;
could add with Realiser
LFE gain + LF redirection downstream LFE gain upstream +10 +10 -10 emulated
LFE gain + LF redirection downstream LFE gain downstream 0 +10 0 emulated
LFE gain + LF redirection downstream LFE gain + LF redirection upstream +10 +10 -10 cascaded
LFE gain + LF redirection downstream LFE gain + LF redirection downstream 0 +10 0 emulated
In some of these cases, redirection is applied where there was no redirection in the measured room. In
these cases, the sound will be as if there were real redirection with the real speakers.