Editing Stage box

{{Short description|Interface device used in sound reinforcement}}
{{for|"state box" in a theater|state box}}

[[File:Audio multicore cable with XLR connectors and stage box.JPG|thumb|A typical analog stage box connected to a [[Audio multicore cable|multicore cable]] (corresponding terminated wires are also visible)]]

A '''stage box''' is an interface device used in [[sound reinforcement system|sound reinforcement]] and [[recording studio]]s to connect equipment to a [[mixing console]]. It provides a central location to connect microphones, instruments, and speakers to a [[Audio multicore cable|multicore cable]] (snake), which allows the [[sound desk]] to be further from the [[Stage (theatre)|stage]] and simplifies setup.<ref name="lsf">{{cite book |last1=Evans |first1=Bill |title=Live sound fundamentals |date=2011 |publisher=Course Technology |isbn=978-1-4354-5494-1}}</ref>

Stage boxes typically consist of a rugged metal enclosure, with [[XLR connector]]s on the front whose signals are routed through a snake. In the traditional sense, a stage box is effectively a simple termination box at the end of an analog multicore cable. However, many modern stage boxes convert between analog and digital, using a single [[twisted pair]] cable instead of an analog multicore.<ref name="ilsr">{{cite book |last1=Boyce |first1=Teddy |title=Introduction to Live Sound Reinforcement |date=2014 |publisher=Friesen Press |isbn=978-1-4602-3890-5 |edition=1st}}</ref>

==Design==
[[File:DI-Box.jpg|thumb|Analog stage box with integrated [[DI unit]]s.]]
Stage boxes typically house 16&ndash;32 female XLR connectors and 4&ndash;8 male connectors, but occasionally {{convert|1/4|in|mm|2}} [[phone connector (audio)|phone connector]]s are used instead. These connections to the mixer are often called ''sends'' (inputs) and ''returns'' (outputs).<ref name="lsf" /> The connector configuration depends on the number of conductors in the [[multicore cable]] (for analog signals), or the bandwidth (for digital signals). Some stage boxes are [[19-inch rack|rack-mountable]] which allows them to be mounted in either a [[road case]] or equipment rack. Smaller stage boxes use compact metal cases which may sit on a stage inconspicuously. Labels on the stage box make it easier to identify cables for troubleshooting and setup.<ref name="ilsr" />

Many stage boxes, especially digital ones, include microphone [[preamp]]s. This is intended to amplify the signal as early as possible in the [[audio signal flow|signal flow]] in order to minimize interference in the cabling. However, this is unfavorable for some sound engineers who prefer the tone of a specific preamp.<ref name="lsf" /> Another feature of some stage boxes is integrated [[DI unit|DI]] interfaces for direct connection of instruments.<ref name="srp">{{cite book |last1=Shea |first1=Mike |title=Studio Recording Procedures |date=2005 |publisher=McGraw-Hill |isbn=0-07-146957-5}}</ref>

==Digital stage boxes==
[[File:DiGiCo SD9, Expomusic 2010.jpg|thumb|[[DiGiCo]] D-Rack digital stage box next to a SD9 mixer]]
[[File:Allen & Heath AR2412 front.jpg|thumb|[[Allen & Heath]] AR2412 digital stage box, with a [[Cat 7 cable]] carrying digital audio to the mixing console]]
{{further|Audio over Ethernet|Digital mixing console}}

[[Digital mixing console]]s inherently introduce conversion between analog and digital signals. Since digital signals are practically immune to noise, it is preferable to use them for long cable runs.<ref name="taoe">{{cite book |last1=Horowitz |first1=Paul |last2=Hill |first2=Winfield |title=The Art Of Electronics |edition=2nd |publisher=Cambridge University Press |date=1989 |pages=[https://archive.org/details/isbn_9780521377096/page/471 471]–473 |url=https://archive.org/details/isbn_9780521377096 |url-access=registration |quote=digital analog noise. |isbn=0521370957}}</ref> As a result, many modern stage boxes contain an array of [[digital-to-analog converter|DACs]] and [[analog-to-digital converter|ADCs]]. This allows all the signals to be transmitted over a single twisted pair cable rather than a bulkier and more expensive analog multicore.<ref name="ilsr" /> Digital stage boxes are typically easier to set up and more reliable than their analog counterparts, and their cables are much more compact. Some digital stage boxes are designed for use with analog mixers, and this type include a corresponding converter box which is located at the mixing console. This converts the input signals back to analog to feed in the mixer.<ref name="lsf" /> Others are intended for use with a digital mixer, and a cable can be connected directly from the stage box to the mixer, or through an [[Ethernet switch]] in some cases.

One of the main disadvantages of digital stage boxes, and [[digital audio|digital audio systems]] in general, is their [[latency (audio)|latency]] which is introduced in the [[analog-to-digital conversion|analog-to-digital]] and [[digital-to-analog conversion|digital-to-analog]] conversion processes.<ref name="aviom62">{{cite web |website=Aviom |title=A-Net v. Ethernet: Networking Designed for Audio |date=2009 |accessdate=17 June 2019 |url=http://www.aviom.com/library/Application-Notes/62_A-Net-v.-Ethernet---Networking-Designed-for-Audio.pdf}}</ref> Latency is cumulative through all devices in the signal flow, so more complex networks, especially [[Ethernet]]-based ones, can experience latency significant enough to cause an audible [[delay (audio effect)|delay]].<ref name="aviom63">{{cite web |website=Aviom |title=Managing Jitter, Wander, and Latency in Digital Audio Networks |accessdate=17 June 2019 |date=2009 |url=http://www.aviom.com/library/Application-Notes/63_Managing-Jitter-Wander-and-Latency-in-Digital-Audio-Networks.pdf}}</ref> This was originally a major drawback of digital stage boxes, but recent systems have lowered latency to insignificant levels{{snd}}typically 2&ndash;3 ms.<ref name="ilsr" />

Common cables used for digital stage boxes are [[Category 5 cable|Cat 5e]], [[Category 6 cable|Cat 6]], [[Category 7 cable|Cat 7]], and [[fiber-optic cable]]. The [[EtherCON]] locking connector is commonly used for twisted pair cables.<ref name="ilsr" /> Whilst these cables may be informally referred to as "ethernet", they do not necessarily use the Ethernet protocol, merely the same cables. Many manufacturers use proprietary standards for the transmission of digital audio, for example [[Behringer]]'s ULTRANET, Digigram's [[EtherSound]] or [[Allen & Heath]]'s dSNAKE.<ref>{{cite journal |last1=Frink |first1=Mark |title=Cat5 Digital Snake Stage Boxes |journal=FOH Online |accessdate=16 June 2019 |date=February 2012 |page=37 |url=http://www.fohonline.com/images/stories/12/02/current/37-39.200.1202-savior.pdf}}</ref> Open standards such as [[MADI|AES10]] (used by [[DiGiCo]], [[Soundcraft]], [[Yamaha Pro Audio|Yamaha]] etc.) and [[Comparison of audio network protocols#AES50|AES50]] (used by [[Midas Consoles|Midas]], Behringer, [[Klark Teknik]]) also exist.<ref name="music-group">{{cite web |last1=Walker |first1=Al |title=AES50 – Applications in Live Concert Sound |publisher=MUSIC Group Research UK Limited |url=http://www.aes-media.org/sections/uk/Conf2011/Presentation_PDFs/07%20-%20Al%20Walker%20-%20Applications%20in%20Live%20Convert%20Sound.pdf |date=24 June 2011 |accessdate=17 June 2019}}</ref><ref>{{cite book |title=M32 Digital Console User Manual |url=https://downloads.music-group.com/documents/midas/M32_M_EN.pdf |publisher=MUSIC Group Research UK Limited |author=Midas}}</ref>

==Usage==
In a live setting, all of the microphones and musical instruments on stage connect to the stage box, which then connects to the mixing console with a single cable.<ref name="ilsr" /> This is usually more practical than running many individual cables between the stage and the mixer, especially for [[Sound reinforcement system#touring systems|touring systems]].<ref name="lsf" /> Stage boxes are sometimes also used to connect speakers to a mixer{{snd}}either [[Stage monitor system|foldbacks]] or [[front of house|front-of-house]] speakers. Some sound engineers connect wireless microphone receivers to the stage box and position them in the same rack next to the stage.<ref>{{cite web |last1=La Cerra |first1=Steve |title=Guide to Using Wireless Audio Systems Onstage |url=https://www.emusician.com/how-to/guide-to-using-wireless-audio-systems-onstage |website=Electronic Musician |accessdate=16 June 2019 |date=29 November 2017}}</ref>

In recording studios, stage boxes are used to connect the [[control room]] and the live room. They are commonly rack-mounted or mounted on walls in studios, in contrast to the portable method of installation used for live sound.<ref name="srp" />

==Drop boxes==
{{For|the drop box used in stage lighting|Plug-in box (stage lighting)}}
Smaller stage boxes (typically with 2 or 4 connectors) with shorter multicore cables are called ''drop boxes''. These are typically used to carry microphone signals from one side of the stage to the other, or as an extension cable for a few channels on a larger stage box.<ref>{{cite web |url=https://www.ratsoundsales.com/mm5/merchant.mvc?Screen=PROD&Product_Code=soundtools-catsnake |website=Rat Sound Systems, Inc. |title=CAT Box Stage Box |access-date=8 July 2019}}</ref><ref>{{cite web |url=https://forum.speakerplans.com/8-way-stage-drop-box_topic93510.html |website=speakerplans.com |title=Topic: 8 Way stage (drop) box |date=October 2015 |access-date=8 July 2019}}</ref> The multicore cable attached to a drop box is often called a ''[[Audio multicore cable#Subsnakes|subsnake]]'', although this may also refer to the entire assembly of drop box and multicore cable.<ref name="lsf" />

==References==
{{reflist}}

{{DEFAULTSORT:Stage Box}}
[[Category:Audio engineering]]
[[Category:Audiovisual connectors]]