Sony HT-K170 20GB, Glossary

Additional Information

Glossary

Center mode

Setting of speakers to enhance Dolby Pro Logic Surround mode. To obtain the best possible surround sound, select one of the following four center modes according to your speaker system.

•NORMAL mode

Select NORMAL mode if you have front and rear speakers and a small center speaker. Since a small speaker cannot produce enough bass, the bass sound of the center channel is output from the front speakers.

Front	Center	Front
	speaker
speaker (L)		speaker (R)

Rear	Rear
speaker (L)	speaker (R)

•3 STEREO (3 CH LOGIC)

Select 3 STEREO mode if you have front and center speakers but no rear speaker. The sound of the rear channel is output from the front speakers to let you experience some of the surround sound without using rear speakers.

		Center
Front	speaker		Front
speaker (L)			speaker (R)

Dolby Pro Logic Surround

Decoding system of Dolby Surround sound standardized in TV programmes and movies. Compared with the former Dolby Surround system, Dolby Pro Logic Surround improves sound image by using four separate channels: off-screen audio effects, on-screen dialog, left- to-right panning, and music. These channels manipulate the sound to be heard and enhance the action as it happens on the screen. To take advantage of Dolby Pro Logic, you should have at least one pair of rear speakers and/or one center speaker. You also need to select the appropriate center mode to enjoy a full effect.

• Types of sound

Early reflections Reverberation

Direct sound

• Transition of sound from rear speakers

Direct sound Early

Level reflections Reverberation

Early reflection time Time

Test tone

Signal given out by the amplifier for adjusting the speaker volume. The test tone will come out as follows:

•In a system with a center speaker (NORMAL/WIDE/3 STEREO modes)

The test tone is output from the front L (left), center, front R (right), and rear speakers in succession.

Front (L) Front (R)

•WIDE mode

Select WIDE mode if you have front and rear speakers and a large center speaker. With the WIDE mode, you can take full advantage of Dolby Surround sound.

Front	Center	Front
	speaker
speaker (L)		speaker (R)

Rear	Rear
speaker (L)	speaker (R)

Dolby Digital (AC-3)

This surround format is more advanced than Dolby Pro Logic Surround. In this format, the rear speakers output stereo sound with an expanded frequency range and a subwoofer channel for deep bass is independantly provided. This format is also called “5.1” because the subwoofer channel is counted as

0.1channel (since it functions only when a deep bass effect is needed.)

All six channels in this format are recorded separately to realize superior channel separation. Furthermore, since all the signals are processed digitally, less signal degradation occurs. The name “AC-3” comes from the fact that it is the third audio coding method to be developed by the Dolby Laboratories Licensing Corporation.

Center

3 STEREO

Rear (L, R)

NORMAL/WIDE

•In a system without a center speaker (PHANTOM mode)

The test tone is output from the front and the rear speakers alternately.

Front (L, R)

• PHANTOM mode

Select PHANTOM mode if you have front		5.1 CH/DVD jacks
and rear speakers but no center speaker.		These jacks are used to input decoded Dolby
The sound of the center channel is output		Digital (AC-3) audio signals, allowing you to
from the front speakers.		enjoy 5.1 channel surround sound. Use these
		jacks to connect a Dolby Digital (AC-3)
Front	Front	decoder or a DVD player with a built-in AC-3
		decoder.
speaker (L)	speaker (R)

Surround sound

		Sound that consists of three elements: direct
		sound, early reflected sound (early
		reflections) and reverberative sound
		(reverberation). The acoustics where you hear
Rear	Rear	the sound affect the way these three sound
		elements are heard. These sound elements are
speaker (L)	speaker (R)
		combined in such a way that you can actually
		feel the size and the type of a concert hall.

PHANTOM

Rear (L, R)

20GB