PRSS to Remove 6 dB Boost on Tuesday, January 26, 2016

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The following is an important system message regarding the PRSS plan to eliminate a 6 dB boost on January 26, 2016, at 1:59 pm ET and is intended primarily to accomplish three goals:
1.            Provide the exact time and date of the 6 dB boost removal
2.            Provide instructions on what stations need to do, depending on their technical configuration
3.            Encourage stations with questions or issues to contact the PRSS Help Desk (prsshelp@npr.org or 800.971.7677)
 
As has been communicated to the system, the PRSS is planning to adjust the audio levels of live programs it sends to stations in order to achieve unity gain across the system. Specifically, a 6 decibel (dB) boost, which was added by the PRSS to analog and digital outputs in 2013, will be eliminated. This will have different implications for stations depending on how they use their IDC SFX 4104 Pro Audio receivers’ analog, AES and Livewire ports. This action will take place at 1:59 pm ET on Tuesday, January 26, 2016.
 
This announcement follows efforts made, and communications issued, last winter to perform this action in February 2015. Prior to the proposed date to remove the boost, however, the PRSS determined that additional time and preparation would benefit the system. Accordingly, PRSS engineers have spent the previous months testing and standardizing connections with more than a dozen distributors and producers. (A system message providing an update was sent out to the system on November 12, 2015, and is available at http://prss.org/news/prss-status-update-6db-boost-removal-0 .)
 
The most important message for station personnel is that if the following instructions are confusing or do not reflect a station’s equipment set-up, then they should call the PRSS for assistance now. Stations should not wait until January 26, 2016, to determine their action plan to compensate for the 6 dB boost removal because PRSS engineers, technical experts, and help desk staff will likely be extremely busy on that day.
 
Stations should ensure that these instructions make sense, and that technical staff have a clear idea of what is required in order to compensate for the January 26 boost removal.
 
Currently, with the 6 dB boost in-place, station receivers should provide the following levels, relative to a standard -20 dBFS input and a -6 dB attenuation in the Livewire configuration of the receivers:
AES = -14 dBFS
Analog = 4 dBu
Livewire = -20 dBFS
 
Once the PRSS has removed the 6 dB boost, station receivers should provide the following levels:
AES = -20 dBFS
Analog = -2 dBu
Livewire = -20 dBFS after manually adjusting the receiver (see link to instructions below).  It will be -26 dBFS without this adjustment.
 
In order to achieve the proper audio levels, stations must follow varying courses of action depending on how their audio systems are configured.  It is important to note that the boost removal has different implications for stations depending on how they use their 4104 receivers’ analog, AES and Livewire ports.
 
Livewire
 
When the PRSS removes the 6 dB boost, stations using a Livewire port will have to manually adjust their SFX 4104 Pro Audio receivers to compensate for the decibel takeaway. An illustrated guide for manually adjusting a 4104 Livewire port can be found on the PRSS website at http://www.prss.org/sites/prss/files/documents/Equipment/Changing%20Livewire%20in%20the%204104.pdf
 
AES and/or Analog
 
Among stations using AES and/or analog outputs, there do not need to be any adjustments made to their 4104 receivers. However, stations may need to make adjustments to their own equipment, depending on how their station is configured. If a station’s 4104 receiver is connected to an amplifier, that amplifier will need to be boosted (made louder) by 6 dB. If audio coming out of a station’s 4104 receiver goes directly to air, the station may need to add an amplifier in between with adjustable audio settings.
 
Stations utilizing Analog or AES outputs from their 4104 receivers may have already made modifications to receiver levels at the points where the 4104 signals enter their audio plant. This means that they likely already have made some adjustments to the inbound levels at their router inputs, and so the adjustment on January 26 should be relatively straight-forward.
 
Test Stream Created in ContentDepot
 
The PRSS has also established a test stream at the new boost-less, -20 dBFS level with a single 24-hour program in ContentDepot. Any station can subscribe to this transmission to send the test material to any receiver out port for comparison and determining new preset levels so that the actual change will be a known quantity when it eventually comes.
 
The program is called “Test Program Stream” and can be subscribed to in ContentDepot via this link: https://contentdepot.prss.org/portalui/app/#!program/programId=3874954.
 
Additional Notes
 
When the boost is taken away, the switch will not be instant but may take several seconds to complete over all streams. For this reason, the 1:59 pm ET time was chosen because it’s the last minute before the top of the hour, during which channel switching occurs and which we normally use for network-related changes.
 
Please note: In communications sent to the system in February, the PRSS noted that stations that take live with subsequent file (LWSF) programming will need to raise the audio levels in their automation systems. This will NOT be the case on January 26, and there are no implications or special procedures for stations taking LWSF files – the responsibility for achieving proper levels for LWSFs will rest with the program producers, who will boost their signals for LWSF shows on January 26. The PRSS NOC will be in touch with all LWSF program producers before January 26 to coordinate actions.
 
** To reiterate, stations are strongly urged to ensure their engineering/technical staff understand what they must do on January 26, 2016. If a station has *any* questions or challenges, they should contact the PRSS Help Desk right away. Someone will be in touch to ensure that following the January 26 action, their station’s audio levels will be at the proper configuration. **
 
The PRSS is committed to ensuring that this procedure goes as smoothly as possible, and it is prepared to assist any producer or station personnel with questions. Please use the PRSS Help Desk as the initial point of contact so that we may track and monitor all inquiries. The PRSS Help Desk can be reached at prsshelp@npr.org or call 800.971.7677.
 

Posted: December 17, 2015