T+A Elektroakustik DD 1535 R Stereo System User Manual


 
55
Dolby Headphone
Dolby Headphone is a system which provides a form of spatial sound image even with conventional stereo headphones.
Method of working:
When a stereo signal is reproduced via two
loudspeakers set up in front of the listening position, the
listener perceives the music to be spread out over the
area between the right and left speakers, rather than
directly from the two loudspeakers themselves.
The sound image appears in this way because of sound
reflections: the sound from the front speakers reaches
the ears directly, but is also reflected around the room,
and by the listener’s shoulders and head.
The effect is amplified by the fact that the sound from the
right-hand speaker reaches the left ear as well as the
right ear (and vice versa), albeit with a slight delay.
The net result of these two processes is that it is possible
to locate individual sound sources spread out across the
front of the listening area.
If we attempt to reproduce the same signal using
conventional headphones, the sound from each channel
reaches the associated ear of the listener, but not the
opposite ear. Furthermore the reflections in the room and
the shoulder area of the listener simply do not occur.
The result of this is that the music reaches the listener
directly from right and left, and therefore seems to come
from inside the head rather than being spread out in
front.
This is the reason why many people find headphone
listening an unnatural experience.
Dolby Headphone is a process by which the music signal
is processed to simulate the characteristics of music
reproduction in a normal room; the result is that an
approximation of the usual listening experience is
possible even using headphones.
Dolby Headphone goes even further than this, and
incorporates the rear channels which are present in 5.1 /
7.1 material, providing a genuine cinema-like
atmosphere even with conventional stereo headphones.
Three different types of room can be selected, so that
the listener can match his or her personal preference to
the type of music signal being reproduced:
- DH1 (reference room): small room with pronounced
acoustic damping;
- DH2 (living room): small room, but with less
pronounced damping;
- DH3 (large room): larger room with more diffuse
sound distribution.