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Old 05-22-2008, 12:31 PM
postprosound postprosound is offline
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Default Dolby Facility Requirements

I copied this from gearslutz. Perhaps this should be a sticky?


Theatrical Sound Production Facility Requirements

1. Introduction

Dolby Production Services contracts services and encoding equipment to content owners and
distributors wishing to release their theatrical program in a Dolby format. To ensure the highest
quality and reliability, Dolby requires that these services take place in an audio production facility that
meets the minimum requirements outlined below.

Facilities wishing to be considered for Dolby approval should contact Dolby Production Services.

2. Room Design

2.1. The room must be large enough to accommodate at least “Mid Field” monitoring. The minimum
acceptable room dimensions are 20’ long (Screen to Rear Wall) by 13’ wide with a 9’ ceiling
height. The optimum mix position is located 2/3 the length of the room away from the screen. In
the minimum sized 20’x13’ room, this position is 13’-4” from the screen.

Refer to chart below for acceptable room dimensioning ratios. The shaded area represents
acceptable conditions, whereas the straight line represents the optimum ratio.

3. Speakers

3.1. The screen speakers (Left, Center, and Right) must be the same make and model and must be
behind a perforated projection screen. The screen speakers should be able to reproduce
frequencies +/-3dB from 40 Hz to 16 kHz without assistance (satellite systems utilizing a
subwoofer to achieve full range are not acceptable for use as the screen speakers). The screen
speakers must be able to produce “clean” sound pressure levels (peaking) up to 105dBC SPL.
The location of the Left and Right speakers should not subtend an angle greater than 45
degrees from the mix position. The speaker cabinets should also be mounted at the same
vertical height, which should be mid-screen, for all screen channels.

Rev 20080213 Page 1 of 3




3.2. There must be at least (2) pairs of surround speakers mounted along the sidewalls to create an
effective surround “array”. Larger mixing rooms will have several surround pairs that cover
listening areas in front of and behind the mix position. In smaller rooms, the first pair of
surrounds must be slightly in front of the mix position. The second surround pair should be
slightly behind the mix position.

Mix stages that are to be equipped for Dolby Digital Surround EX must also have at least (1)
pair of surround speakers mounted on the rear wall. A separate two-channel amplifier must also
power the rear surround speakers to allow proper Surround EX monitoring.

For smaller mix rooms, surround speakers should never be directly “on axis” with the mix
position. The surround speaker array must be able to produce “clean” sound pressure levels
(peaking) up to 105dB SPL.

3.3. There must be a separate subwoofer capable of producing an equalized response of 25Hz-
120Hz +/- 3dB. The subwoofer must also be able to produce “clean” sound pressure levels
(peaking) up to 115dBC SPL.

4. Equalization & Delay

4.1. The speaker system must be equalized to the ISO 2969 “X” curve. There must be 1/3 octave or
parametric equalization inserted before the screen channel amplification to accomplish this
equalization. For the surround channels, single octave EQ is acceptable but not recommended.

4.2. If the distance from the mixer to the screen is more than 1.5 times the distance from the mixer to
the surrounds, a suitable delay line should be inserted (Pre-EQ) into each surround channel
monitoring path. It is recommended that the delay line is patchable so that it can be inserted in
the recording chain should a separate picture and track screening master be required.

4.3. A parametric EQ of at least one but preferably more bands and a 120 Hz low pass filter (Pre-EQ)
should be inserted in the LFE (subwoofer) monitor path. The LFE filter should be a 3rd order
Butterworth filter set with a crossover point at 120 Hz. Higher order filters are acceptable, but
lower order filters can cause incorrect perception of the LFE channel. Also, it is recommended
that the 120 Hz low pass filter is patchable so that it can be inserted in the recording chain
should a separate picture and track screening master be required.

5. Level

5.1. After proper equalization, the monitor levels need to be calibrated to 85 dBC SPL for each
screen channel (L,C,R), 82 dBC for each surround channel, and +10 dB in-band gain (RTA
method) referenced from the center channel for the subwoofer. A compliance check of EQ and
levels by a Dolby engineer must be performed prior to commencement of each contracted mix.

5.2. The sound system must be designed to provide a minimum headroom specification of +20dB
above normal reference level for each channel.

5.3. The console monitor section must have a multi-channel assignable fader with at least six inputs
and outputs. The monitor section must also provide a ‘fixed reference level’ mode for proper
listening levels when mixing and print mastering.

Rev 20080213 Page 2 of 3




6. Equipment

6.1. Dolby will supply a Digital Mastering Unit (DMU) to approved 5.1 mixing studios IF the length of
the film is 40 minutes or more. For short subjects or trailers, the film must be mastered to a
digital multitrack format and transferred at an approved Dolby Digital transfer facility..

6.2. Studios that are approved to use the Dolby DMU mastering system must also meet certain
business requirements (films per year) to be considered for a permanent installation. For studios
not meeting these business requirements, Dolby supplies a traveling DMU on a “per-mix” basis.

6.3. The “Dolby Surround Tools” plug-in for ProTools can not be used to create an Lt/Rt during the
final film print master. This plug-in does not facilitate the proper metering and processing needed
during mastering. Although the plug-in cannot be used for print mastering, it can be used for pre-
mixing. Also, any analog tape machines being used for the mix should be equipped with Dolby
SR noise reduction

Note: Dolby Laboratories, Inc. Model CP650 is a recommended cinema processor for decoding many
formats such as: Dolby Digital Film Soundtrack, SR/A Optical Film Soundtrack, and Digital 5.1 and
Lt/Rt Studio Masters.



Rev 20080213 Page 3 of 3
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  #2  
Old 05-22-2008, 02:41 PM
Craig F Craig F is offline
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Default Re: Dolby Facility Requirements

Digi - please pin this
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PT11 System Requirements link http://avid.force.com/pkb/articles/C...m-Requirements


Thank you,

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Old 05-22-2008, 02:50 PM
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dr sound dr sound is offline
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Default Re: Dolby Facility Requirements

I put a link to this on the "Room Calibration for Film and TV" sticky.
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Old 05-22-2008, 03:08 PM
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DigiTechSupt DigiTechSupt is offline
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Default Re: Dolby Facility Requirements

Done!
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  #5  
Old 09-30-2008, 03:08 AM
Greg Marshall Greg Marshall is offline
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Default Re: Dolby Facility Requirements

I'm Currently building a new Dolby Room, please beware that in light of the Premier Dolby Certificate the specifications have recently changed. I strongly recommend anyone setting up a room to Dolby Spec to contact Dolby for the latest details - I've just had to get the architects to move a wall 300mm to meet their new requirements!!

Greg Marshall
http://www.imdb.com/name/nm1419233/
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  #6  
Old 10-01-2008, 03:11 PM
danijel danijel is offline
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Default Re: Dolby Facility Requirements

These are 20 days old:

6.0 Technical Requirements for Studios to Obtain
Dolby Certification


6.1. The first essential requirement for the dubbing theatre is to monitor Dolby
mixes correctly, as well as play your own and other studios' printing masters
and optical soundtracks. To this end you will need to install a Dolby cinema
processor type CP650S1. The CP650S will provide analogue and digital
optical replay, Surround-EX decoding, matrix decoding, full equalisation2 for
loudspeaker calibration on all 7 channels, surround delay and master monitor
level control. The CP650S uses AES/EBU digital inputs and analogue, digital
or analogue cross-over outputs.

6.2. Optical replay of both the analogue and digital optical track is required for
foreign version and original feature mixing to allow the studio to match the
original recording, or to check the quality of an “Answer Print”. This will require
a solar cell and bracket assembly for analogue replay, as well as a Cat. No.
702 or an approved Dolby Digital reader to be added to the projector or sound
follower. The sound follower or projector must be able to run in synch with the
studio recorders.

6.3. The screen and surround speakers and amplifiers must be capable of
providing a frequency response to ISO2969 and, with the requirements of
Dolby Digital in mind, must be able to provide an SPL of 105dBC for peak
levels, after acoustic calibration, without distortion.
Theatre type speakers (pressure drivers with suitable horns) will be required in
medium to large rooms and these should have electronic crossovers.
Appendix A gives further guidance.
Bass management systems are not suitable.
The Dolby Studio Approval Calculator should be used to verify loudspeaker
and amplifier performance capabilities.
Suitable test material is available to check monitor headroom capability (“Jiffy”
test film tone sweep test and a pulsed short duration 0dBfs pink noise test).
Please note that Dolby level pink noise, 85dBC, equates to around -14dBfs.

6.4. The screen speakers must be at a height to give good coverage in the mixing
and listening area. When projecting a 2.35:1 picture the left and right speakers
will be inside the edge of the picture area and provide a 45° angle ± 5° with
the mixing position. If masking is used this must be of the acoustically
transparent type. We recommend that the mixing position be placed 2/3
back from the screen and require that the screen is at least 5 meters from
the mixer. The studio area will be greater than 45 meters square and room
volume will be greater than 150 cubic meters. We will allow some small
deviation to these requirements if, in our opinion, the proportions of the room
and equipment layout are spoilt in order to comply. Room ratios will be within
the shaded area shown in Figure 1 below and ideally close to the straight line.
Figure 1 Ideal Room Ratio
1 See Appendix B for selection chart
2 We strongly suggest that no external equalisation is used as headroom or S/N in some frequency bands may be
compromised.
Rev 31 Page 7 of 12

6.5. The acoustics of the mixing room must conform to the acoustic characteristics
shown in Figure 2. The reverberation time should ideally diminish and show no
reversals with increasing frequency.
Figure 2 Reverberation Time

6.6. Ambient noise levels must not exceed NC-25 as measured according to ISO
9568 Background acoustic noise levels in theatres, review rooms and dubbing
rooms.

6.7. Two track only “Printing Masters” must be supplied SR encoded for transfer to
optical sound negative on RDAT, Hi-8 (DTRS) or as .wav files. Dolby Digital
“Printing Masters” (6 track and 2 track) will be recorded on a Dolby Digital
Master MOD (Magneto Optical Disk) within the Dolby Digital Encoder for
transfer to optical negative. They must also be recorded to .wav files or Hi-8
(DTRS) tape. Some customers may still request them on 35mm magnetic film
with SR noise reduction.

6.8. Mixing consoles must have a minimum of 32 channels providing full
processing such as gain, EQ, dynamics and pan. The console must provide a
minimum of 24 professional grade faders at least two panoramic controls to
move sounds between at least four channels and preferably six. There must
be a minimum of 8 group outputs. If the studio intends to mix big budget
original productions the above will need to be significantly increased.

6.9. The monitor section of the console must provide PEC/DIR (direct/replay)
switching for 8 signal paths and a 16x8 summing monitor matrix to provide
correct monitor routing during pre-mixing. It must allow individual solos and
mutes of source and monitor channels. If the studio intends to mix big budget
Rev 31 Page 8 of 12
original productions, the number of PEC/DIR switches and matrix inputs will
need to be significantly increased. Virtual (internal) as well as external
solutions are acceptable as long as the user interface is dedicated to this
function.

6.10. The DMU and MME encoders have AES/EBU digital inputs. A Dolby or thirdparty
ADAC may be used for interfacing the encoder to analogue consoles, but
in order to enable full and correct functionality of the encoder, any third-party
ADAC must comprise:
• 8 channels of analogue to digital and digital to analogue conversion.
• A conversion from the studios analogue level to -20dBfs. Normally this
would be 0dBU or +4dBU equating to -20dBfs.
• Headroom of 20dB above the analogue reference level.
Converters not meeting the above specifications will not be accepted. If in
doubt please advise us the make and model number intended.
A suitable safety limiter on the input to prevent hard clipping at levels over
20dB above reference is not a requirement but is a valuable addition to the
specification.

6.11. Level standardisation at –20 dB below MSB or clip in the console main outputs
and recorders is essential. You may wish to check with the manufacturer that
digital and line levels conform to accepted standards i.e. +4dBu or 0dBu line
level for –20 dBFS internal console level and that the meters read –20 dB.

6.12. For synchronisation, the Dolby encoders require time code and video
reference signals. The DMU can also work with biphase (a 240 or 48 pulse per
frame bi-phase signal for a 24 frame per second rate). The studio must ensure
they can supply the appropriate synchronisation signals prior to digital
mastering.

6.13. Video projection must provide an image that when projecting a film made in an
aspect ratio of 1.85:1 (flat) or 2.35:1 (scope), covers the width of the screen to
at least the outer edge of the left and right screen speakers. Reflected light
from screen (measured at mixing position) must be at least 12fL, and the pixel
resolution of the projector must be a minimum of 1920 x 1080. Processing
delay must be known and compensated for by a suitable timecode offset to the
video replay device. If in doubt, please provide us with specifications and we
will determine suitability.
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  #7  
Old 10-01-2008, 03:13 PM
danijel danijel is offline
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Default Re: Dolby Facility Requirements

4.0 Technical Requirements for Studios to Obtain
Dolby Certification for Commercials and Trailers
only


4.1. The first essential requirement for the dubbing theatre is to monitor Dolby mixes
correctly (all formats, Dolby Stereo, Dolby Digital and Dolby Digital Surround
EX) as well as the possibility to play their own and other studios' 6 and 2 track
printing masters. To this end you will need to install a Dolby cinema processor
type CP650S1. All versions will provide inputs for stereo solar cells, full matrix
decoding, 1/3-octave equalisation for loudspeaker calibration, master monitor
level control, Surround EX and all digital processing. Balanced or AES/EBU
input/output lines are available as options.

4.2. Optical replay of the analogue and digital track is not a requirement but is
recommended in order to check the quality of an answer print. This will require a
solar cell and bracket assembly to be added to the projector or sound follower
and a digital reader. Your CP650 may also require an additional module. Please
inform us if you wish to have optical replay facilities.

4.3. The picture must be projected onto a screen (preferably perforated or woven)
TV monitors are not acceptable.

4.4. Screen and surround speakers and amplifiers must be capable of providing a
frequency response to ISO2969 and, with the requirements of Dolby Digital in
mind, must be able to provide an SPL of 105dBC for peak levels, after acoustic
calibration, without distortion (Appendix A). Theatre type speakers (pressure
drivers with suitable horns) will be required in large rooms and these should
have electronic crossovers. The screen speakers must be at a height to give
good coverage in the mixing and listening area. Speaker systems with bass
management are not suitable. When projecting a picture the left and right
speakers should be inside the edge of the picture area and ideally provide
between a 45 degree angle with the mixing position. We recommend that the
mixing position be placed 2/3 back from the screen and we recommend that the
screen is at least 5 metres from the mixer.
The Dolby Studio Approval Calculator (Commercials and Trailers only) should
be used to verify loudspeaker and amplifier performance capabilities.
Suitable test material is available to check monitor headroom capability (“Jiffy”
test film tone sweep test and a pulsed short duration 0dBfs pink noise test).
Please note that Dolby level pink noise, 85dBC, equates to around -14dBfs.
1 See Appendix B for selection chart
Rev 13 Page 6 of 10

4.5. The acoustics of the mixing room must conform to the acoustic characteristics
shown below in Figure 1. Ambient noise levels must not exceed NC-25 as
measured according to ISO 9568 Background acoustic noise levels in theatres,
review rooms and dubbing rooms.
Figure 1 Reverberation Time

4.6. Two track “Printing Masters” must be on .wav, RDAT or Hi-8 format (DTRS).
Six-track “Printing Masters” must be on .wav or Hi-8 format (DTRS).

4.7. Mixing consoles must have a minimum of 20 input channels and 6 main output
groups. Mixing consoles designed for music mixing may need modification to
obtain correct insertion points for the Dolby encoder/decoder. The console
should have at least two panoramic controls to move sounds between at least
four channels and preferably more.

4.8. Level standardisation at –20dB below MSB or clip in the console main outputs
and recorders is essential. You may wish to check with the manufacturer that
digital and line levels conform to accepted standards i.e. +4dBu or 0dBu line
level for –20dB MSB internal console level and that the meters read –20dB.

4.9. It is a requirement by most organising bodies and Dolby Laboratories that the
level of commercials & trailers is controlled and monitored using a Leq (m) meter
(British Standard BS 5550-7.4.2). Commercials & Trailers made above the
requirement will be rejected.
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