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Threescenarios:

The room is a mess You knowhow it is. “We have the slick-est audio post room in the

city, but do they use our built-in con-veniences? Noooo, they’re bringing inall their own stuff from the outside!The lock-out session over the last cou-

 ple of days has left keyboards, racks,video monitors and MIDI cables scat-tered over every inch of available con-trol room space. And you don’t wantto touch it, ‘cause it took the first dayand a half of the session to get it work-ing the way the client wanted. Butyou’ve got to, because the VAPP (vid-eo-audio-post-production) date iscoming into the room in an hour.That means a day for the previouslock-out session to get back into gear,and they are not going to want to payfor it . . . .”

“Great, we’ve had the roomworking successfully for al-most six months, all the cable

n, and our synthesist has to besurgically removed from his program-ming position. The client wants to usehis PC instead of our Mac, and the JamBox will be replaced by the Cooper.SBX-land! SMPTE lines draped acrossthe outboard, and on top of all that, hedoesn’t like the location! Oh well, itwas too good to last. Just as well, wedon’t have the lines in place for themaster controller anyway, so we just

have to do it all over again. . . .”

“While running the multi-track a s  a slave to the video ma-

chine, the room has no opera-tional problems. But now the new“main client” wants a 32-track  digitalmachine and everyone feels it’s toonoisy to keep in the control room.

 Now we have to rip out the transportcontrol lines from the trough, movethe audio feeds and put the synchro-nizers in a position that will be com-mon to three different areas. We were

38  MIX, NOVEMBER1988 

warned that the maximum length wecan run on the control line for thecapstan is about 35 feet, and that’s noteven half the distance we have tocover. This is going to be a lot of work if they don’t like working that way”

Change. . . it’s one of the only con-stants of the recording industry As an

industry, we have accepted the neces-sity of being able to “shape-shift” our 

 business plans to stay alive. Becom-ing a specialist and targeting a smallsegment of the market has been oneroute of survival for many, while oth-ers see being a “generalist” as the keyingredient to success. To accommo-date the diverse clientele that the in-dustry offers, our equipment selection,orientation and functional controlroom/studio ergonomic environmentmust also be able to change. Oftenwe do not know where the business

is going, which makes it extremelydifficult to allocate our resources in

by Greg Hanks

one given direction with completeconfidence. This is illustrated by theextreme changes in studio methodol-ogy that MIDI has brought about. Wetherefore must be as flexible as pos-sible, not only in our business plans

 but also in our equipment choicesand room design and construction.

Our company, New York TechnicalSupport, provides efficient workingenvironments, designing around theabove-mentioned problem scenarios

 by anticipating the demands of theclientele. Over the course of design-ing and installing the last eight to tenstudio/control rooms we did, we haveincluded:A. A 25-conductor  cable to outboardequipment locations. This cabling isintended for use with synchronizationequipment.B. “Synthesizer stations” in the rear of 

the control room with audio and MIDIcapability.

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C. MIDI jacks on connector panels onthe top and rear of outboard equip-ment racks for external synthesizersand processing gear. These jacks ter-minate in a wiring location that is per-ceived as central to the operation of MIDI-based equipment, such as at aMIDI patch bayD. High-level cable to the outboard

racks, console and synthesizer loca-tions.When a new installation is com-

 plete, everything works fine. As longas the room’s function is not requiredto change, the solutions originally of-fered by the installation prove highlysuccessful. When the business climaterequires a radical re-direction of a stu-dio’s equipment use, in some caseswe found the above remedies to beinsufficient. For instance, when we

 provide one data line, the neededequipment rearrangement requires

two. When we provide two data lines,we find we now need one for dataand one for video. We found ourselvesin that position one too many times.An established client of ours commis-sioned us “way back when” to assem-

 ble a little 8-track   pre-productionroom. When we were requested torewire the room to accommodate asecond synthesist, second 24-track,  asynchronizer and video system, wedecided that a new approach was ne-cessary. This article is an outcome of that decision and the resulting room.

Using traditional design methods,we allocate a piece of equipment to alocation the user desires, typically inclose physical proximity to other equipment of a similar type. The wir-ing necessary for accessing its func-tions is then put in place. Normally, afew flies get into the ointment alongthe way and these flies are what westrive to eliminate. For example, haveyou ever successfully integrated a PCinto the console automation system,only to have the computer’s fan andhard disk noise become a major an-

noyance? Well, the answer is to putthe computer in a soundproof box, or move it out of the control room (aconvenient location might be the am

 plifier  closet or the room closest tothe control room). Either way, thedisk drive is now inaccessible for the

 person attempting to back up the harddisk, making that task even more on-erous and less often performed than

 before. It also means we must add asecond keyboard and monitor at thenew computer location, and add

SMITE, automation data, keyboard ex-tension and monitor extension ca-

 bling from the new computer locationto the operator’s position.

When contemplating any change inconsole location, rack location or anequipment addition, keep these ca-

 bles in mind. Most wiring systemswe’ve created allow for expansion and

modification of the system design, butchange sometimes requires differentfacilities than anticipated.

Driven by such difficulties, we setout to find an equipment installationmethod that could be all things to all

 people, over a long period of time.We wanted to provide our clients withan environment that could accommo-date almost any rearrangement of thecontrol room that their clientele mightrequest, as well as integrate as yet un-defined technological advancementsin the areas of console automation,

MIDI sequencing, synchronizationand video post-production.Our list of requirements included:

(1) ability to hide all MIDI cabling;(2) ability to place the video moni-tor(  s) or VCR where it is most conven-ient, not where someone laid cablefor it a couple of years ago;(3) feasible relocation of the synchro-nizers to a convenient operator posi-tion, with the ability to add a control-ler by adding a few wires and chang-ing some jumpers;

(4) coherent signal grounding withall processing gear, including videoand data;(5) ability to easily move noise-pro-ducing equipment, such as comput-ers, out of the control room, whilemaintaining their functionality; and,(6) ability to easily change the con-figuration of a single piece of equip-

ment, as well as a large grouping of equipment, and then reconfigure thesystem as it was before, when theneed for the change ceases to exist.

We are not the first to arrive at theserequirements, and many before ushave accommodated these needs viathe concept of a “central patch” facil-ity, in which all wiring to and from allequipment terminates at a central lo-cation. (See “Lucasfilm’s Skywalker Ranch,” M&August ‘88.) This doesnot overcome the difficulties of phys-ically relocating a piece of equipment,

 but makes changing its interfaceeas

ier. A central patch is more orientedto multi-room facilities and does notaddress the individual control roomvagaries.

A NewAlternativeA different type of wiring topologywas required to satisfy the aboveneeds. We found a system that has

 been in use in other industries for years: the “ backbone” interconnectsystem that serves telephone, data and

 NOVEMBER 1988, MIX 41

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PABX networks.The concept of a backbone system

is one whereby all of the conductorsnecessary to accommodate any givensystem task appear at all equipmentlocations. This implies that at all equip-ment locations we have the ability toaccess a wiring system that will enableus to interconnect:

-audio, both sends and returns of mic level, line level and speaker level;-video sends and returns;-data: serial and parallel formats of dynamic data as well as machine tally,DC levels for things such as servo con-trol, and static data lines for monitor and machine selection and control;-SMPTEand MIDI;-grounding and shielding.

In the traditional methods used bytelephone companies, this simplymeans there are two to 34 conductors

42 MIX, NOVEMBER 1988 

running from a central panel to each“user” location. A few minor changesare needed to make the concept fly inthe modern recording environment.After all, it’s difficult to get an M-49 tosound right after it has been routedaround the building on a twisted pair!

To implement a backbone design inthe recording environment, we must

first determine the type of functionalgroupings we’ll have, how to intercon-nect them and the manner of internalcohesiveness that will make the sys-tem truly flexible. In doing so, wemust define several system concepts:

Central panel: The location atwhich all conductors forming the back- bone terminate. At this location, eachgrouping of function will be intercon-nected. This is oriented to a singlecontrol room. In a multi-room facility,each control room’s central panel can

terminate in a “central patch” by treat-ing the central patch as one or more“pod” locations. Such a system is hier-archical in organization but distrib-uted in function. For cost considera-tions the central panel can be locatedunder the console, although altemate-ly it can live in a closet down the hallfrom the control room. The uniform-

ity of pin-outs and the consistency of connector types are the essential ele-ments of success in achieving systemflexibility. All audio connections aremade through the same type of con-nector. All data connections are madethrough the same type of connector as the audio, but in a different shelltype, so as not to inadvertently cross-connect the two signal types.

Pod: A grouping of equipment thatlives at any of a number of locations.The most common pod is a rack fullof outboard gear. This equipment is

assembled as desired within a rack,and wired to the pod termination,which is location-independent. Thereare many locations where this podcan be connected.

GPAB: The acronym for “general- purpose audio bus,” and the name of the audio trunk line that serves as theaudio “pipe” in the backbone system.In our design, this is a directionallyoriented line, so it has two parts:sends and returns.

GPDM: The acronym for “general- purpose data and MIDI trunk,” which

 provides for all the data, MIDI,SMPTEand control lines needed for a givenfunction. We also directionally orientthis trunk to provide for proper shield-ing and grounding with the many di-verse requirements imposed upon it.

Video: A bi-directional series of lines for general-purpose, constantimpedance use.

High-level: We provide two stereocue systems and one stereo pair of  bidirectional, genera-purpose, high-level lines. High-level lines are desig-nated for use with speaker levels.

Some functional groups require adedicated location. Their locationsare mandated by many different cri-teria, including size, heating and cool-ing requirements, acoustic relation-ship to the monitor speakers and elec-trical power requirements. Consider-ing such criteria, we can see that theconsole, monitor rack, computer rack and monitor speakers fall into thiscategory.

These functional groupings are notwhat give us grief when we need to

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.  .  . look at t he ease wit h which 

we can change t he f ace of t he 

cont r ol r oom t o mat ch a desir ed 

f unct ion.

change the control room functions, but remain stable in the functionalequation. We therefore find  that allother functions fall within our stateddefinition of a pod. A pod can be amulti-track tape recorder, a Dolby sys-tem, a rack of MIDI-based synthesiz-ers, a 2-track, a rack of cassette record-ers or another complete control room!

We must accommodate the console,the monitor rack and the computer rack interface at the central panel aswell as provide for all the different pod locations. At each pod location,as well as at each dedicated functionlocation, we allocate these signals: au-dio (mic level, line level and high lev-el); data and MIDI signals; video; andgrounds.

 Next, we must decide upon the sys-tem’s level of capability. This is mosteasily stated as, “How many different

 pod locations do we need?’ Looking

at the cable requirements (pg. 42) for each pod location, we see that withan excessive number of pod locations,our cable, connector and labor costsstart to escalate drastically. At a min-imum we must support all consolefunctions, all monitor and computer rack functions and at least six podlocations.

In our first backbone installation,we decided to integrate the monitor and computer racks, supplying oneGPAB, two GPDMs   and two videotrunks. This has proven sufficient. Ex-

 pandability has been accommodatedvia modularization of the wiring sys-tem, which was accomplished throughusing a standardized connector paneland a standard definition of the pod.If we need more pod locations in thefuture, we simply bolt in another cou-

 ple of connector panels, constructmore pod trunks, drop them in thetrough and we’re done. The only lim-iting factors are rack space at the cen-tral panel location and room withinthe trough for the additional wires.

Use of fhe Backbone ConceptIn setting up the backbone, we de-fined certain functions.

Console: The entire console wasinstalled to the central panel. We per-formed several modifications to theconsole, so we put additional connec-tors on the console-to-central-panelinterface to accommodate data, MIDI

and other audio. These lines all followthe same pin-outs as the pods’ andmachine room GPAB and GPDM lines.We recently realized we could replacethe console within an hour or twousing the backbone system, assumingthat we preassembled the console-to-central-panel interface.

Multi-track machines: Becausewe did not wish to access the audioand transport remotes of two multi-track tape recorders via the central panel, and the multi-tracks were setup right near the amp rack in a ma-

chine room, we decided to dedicatethose functions rather than commit anentire pod trunk to each machine. Weallocated one GPAB to each machine.All remote audio and transport func-tions to be accessed by other systemsare interfaced through the first GPDMtrunk of the machine room. We evenhave a remote VSO running from theconsole through the backbone!

Two-tracks: We have five 2-track machines in this system. Two-track #1is a digital recorder, and lives near themulti-tracks. The feeds to and from

traverse the machine room GPAB, andthe transport and audio remote arevia the first machine room GPDM. Theother 2-tracks  live in a rack with other outboard equipment. We use that rack as a pod, and the outboard, cassettesand Fl  all live happily together. Inthat rack we do have a remote moni-tor selector for the last two machines.The to and from wiring for this selec-tor is handled through the central panel, making this selector easilymoved and/or changed.

Console automation:We’re us-ing a PC-XT, disk-based automationsystem for the room. The computer lives in the machine room, while thekeyboard and monitor reside at theconsole.

MIDI lnstrumentation: The MIDI-

 based sources in the room show upin three different pods. One is a dedi-

cated keyboard controller, with anIBM AT monitor, mouse, printer andkeyboard living in the control room.The computer itself, along with a Ro-land MPU-401 MIDI interface, lives inthe machine room. At another loca-tion we have an additional dedicatedcontroller, keyboard, mouse and mon-itor. This location uses a Mac II andagain, the computer lives in the ma-chine room. At yet another location,we have a J.L. Cooper 1620 MIDI patch bay operating in conjunction with aJam Box. All MIDI information from

each synthesizer, computer and key- board routes through the central pan-el to these MIDI patching devices.Within the machine room itself, wehave another pod position for other MIDI-based sources that do not re-quire direct operator access. We caneasily relocate the pod that lives atthe location by changing a couple of connectors (about five minuteswork!).

Outboard equipment: We havetwo racks dedicated to audio out- board. These racks, as well as the MIDI

instrumentation groups, have our tra-ditional panels on the top of the rack for interfacing external outboard(equipment brought in from rental or other sources). These panels now in-corporate MIDI lines that show up atthe MIDI patch bays.

To appreciate the benefits of thiswiring approach, we have only to look at the ease with which we can changethe face of the control room to matcha desired function. An example of thiswould be, say, to build a rack of eightcassette decks for real-time duplica-

tion. Add a monitor selector and asource selector and terminate thewhole sucker as a pod. You can pick up the control lines from the consolethrough the GPDM lines, pick up thesource signals through the GPABsends and return the output of themonitor selector to the consolethrough the GPAB returns.

Another example would be to de-cide to run the 24track from wherethe outboard equipment rack was be-

-CONTINUED ON PAGE 204 

44  MI X, NOVEMBER  1988 

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