Cambridge Audio 640Razur user manual Speaker delay

Set the package as 5.1, 6.1 or 7.1 by highlighting the Decode Mode item and using the Left and Right arrows to scroll through the options:

Speaker Config Menu

Decode Mode	:7.1
Front L/R	:Large
Centre	:None
Surr. L/R	:None
Surr. LB/RB	:None
Subwoofer	:Off
[FL/R Must Set Large

azur	640R
2. Speaker delay
Because the speakers in a surround sound system are usually different		ENGLISH
distances from the listener the 640R incorporates the ability to apply a

variable digital delay to each of the channels so that the sound from each arrives at the same time at the listening position for best surround- sound effect. Each pair of speakers (i.e. Front Left and Right or Surround Left and Right) are subject to the same delay and so must be situated equidistant from the listener.

To set the delay times simply measure the distances from the listening position to each speaker as shown in the following diagram:

When	Sub. Set Off]
Return	To Menu	: [OSD]

Now move down and by highlighting each speaker in turn and using the Left and Right arrows select from ‘Large’, ‘Small’ or ‘None’ for each speaker. 'Large' or 'Small' are used to describe each speaker in terms of bass response, they do not necessarily reflect the actual physical size of the speaker.

Large = Speakers with an extended low frequency response of approximately 20-40Hz to 16-20kHz (floorstanders or high quality larger stand-mounted speakers).

Small = Speakers with a less extended low frequency response of approximately 80-100Hz to 16-20kHz (small stand-mounted, bookshelf

1

3

5

1

2

3

4 5

1 = Front Left & Right speakers

2 = Centre speaker

3 = Surround Left & Right speakers

4 = Surround Back speaker (when used)

5 = Surround Back Left & Right (when used)

or satellite speakers).

Setting each speaker allows the 640R to perform what is called Bass Management and to direct low frequency bass from music and the Low Frequency Effects channel of surround sound material to those speakers best able to reproduce it. If you do not wish to use any of the speakers set its setting to ‘None’.

The Subwoofer output can also be set to On or Off. If no sub is being used make sure this setting is set to Off to allow the 640R to re-direct the bass information in this channel to other speakers.

Note: The 640R will force some speakers to certain settings in some of the following circumstances!

The Front Left and Right speakers may be ‘Large’ or ‘Small’ but never ‘None’ as they are always required for any type of music/movie reproduction.

Bass must always be reproduced by either the Front Left and Right or Subwoofer channel (or both). Setting the Front Left and Right to ‘Small’ will result in the Subwoofer automatically being set to ‘On’. Setting the Subwoofer to ‘Off’ will automatically result in the Front Left and Right being set to ‘Large’.

If the Front Left and Right cannot reproduce low frequency bass a Subwoofer must be used. I.e. If the Front Left and Right are set as ‘Small’ the Sub must be Set to ‘On’.

Also, setting the Front Left and Right as ‘Small’ will always set the other speakers as ‘Small’ (and the Sub to ‘On’). This is because LFE/ bass information should not be redirected to the surround channels.

To store the setting simply come back out of the OSD (pressing the OSD button always moves back one menu item, and then exits and stores from the main menu screen).

Note: No delay setting for the subwoofer is necessary.

Set the distances in the OSD Speaker Delay menu to the nearest value in metres (1 foot = 0.3 metres). The speed of sound is approx 340 metres per second, the 640R thus introduces approx 3mS of delay per metre of distance set.

Go to the ‘Speaker Delay Menu’ and highlight each speaker in turn. Set the distance to the nearest value to that which you measured by using the Left and Right arrows (the values do not need to be exact):

Speaker Delay Menu

Front L/R	: 7.14m
Centre	: 5.44m
Surr. L/R	: 4.08m
Surr. LB/RB	: 3.06m
[Unit	:Meters]
Return To Menu	: [OSD]

Press the OSD button to exit the menu.

Note: In addition to the delays as set above Dolby Pro Logic II/IIx playback also requires an extra 15 milliseconds delay to the surround channels only. This extra delay is part of the Dolby Prologic II specification and ensures that sound from the surrounds arrives just after sound from the front reducing the audibility of sound leakage from the front to the surround speakers. Because the relationship between the Dolby Digital and Dolby ProLogic IIx two delays is fixed (15mS extra to the surround channels), it is only necessary to set the delay by measuring the distances as we have described. The 640R will automatically provide the appropriate extra delay whenever you switch to a Pro Logic Mode.

15