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EMI Console circa 1960

EMI Console Type ROU101 C.1960 Serial Number 1

This Console Is Basically Two Five Channel Mono Mixers Side By Side.Each Mixer Has A Five Line Level Inputs With The First Four Having 806 Microphone Amplifiers In Circuit With Inserts Available On The Jackfields (Under The Two Doors Each Side Of The Console) To Allow The 806 Units To Be Used Independantly. Channel Five Has No Dedicated Microphone Amps And Instead Iy Has A Line Input Changeover Switch To Choose Between Two Line Inputs On That Channel.

Each Channel In A Set Of Five, One Set “a” One Set “b” Has An Echo Send Control Plus A Master Leaving The Echo Send Xlr On The Rear Of The Console At Line Level Via A Valve Bus Amplifier.

These Five Channels Enter Five Band Valve Eq Units With Bass And Treble, And A 0 To +11 Boost Midrange With Selectable Frequencies. The Output From These Is Presented (Via The Jackfield) To Five Elcom Quadrant Faders. These Are Stepped Attenuators Od Type 1300 And Their Scales Are Illuminated From The Bottom In Orange With The Fader Closed (Towards User) And From The Top On Green With The Fader Opened (Away From The User) This Looks Fantastic.

From The Faders, Signals Enter Into A Transformer Isolated Mixer Section, With It,S Own Valve Line Amp. Each Line Amp Has Two Separate Balanced Outputs, Off Two Independent Output Transformer Windings. One Winding Drives The Line Out Xlr,S, The Second Drives A Switch Choosing Between Tape Machine Input Or Console Output. The Output Of This Switch Drives The Studio Loudspeaker Xlr, And The Signal Also Feeds The Pa Out Xlr Via One Channel Of A 10 Watt Valve Amplifier (With Valve Rectifier).

The Echo Returns (Via Rear Xlr) Enter Another Pair Of 806,S (Presumably From Microphones In A Real Echo Chamber) Through Another Pair Of Eq Units Then To Elcom Quadrant Faders “a And “b And Thence To The Mixer Section.

The Insert Points On The Jackfields Between Eq Units And Fader On The 10 Channels Have Been Wired So That The Eq Units Are Available For Use independently.

The Post Mix Signals Can Be Joined Together Via The Stereo/Mono Switch To Make The Console 10 Into 1. The Valve Twin Channel Ppm Meter Can Also Be Switched Into A, A+B Or B Reading.

The Talkback Microphone Is Fed Via A Valve Amplifier To The Studio Loudspeaker Outputs Via The Talkback Relay.

Two Sets Of Sum And Difference Transformers Are Accessible Via The Two Jackfields, Very Handy (If Your Into That Sort Of Thing)

Okay Now For The 806 Microphone Amplifiers. They Have 40 To 80 Db Of Gain In 10Db Steps On The Front Panel With What Are Populary Known As “magic Eye” Indicators For Level Indication. On The Rear Of The Microphone Preamplifiers Is A 3 Postion Switch Selecting Input Impedances Of 30,200 And 600 Ohms. Ribbon Microphone Users Eat Your Heart Out. The 806,S Run On 325Vac (Mind Your Fingers) And Each Has Its Own Psu Components. The Heaters Run On Dc For Noise Reduction Derived From Huge Selenium Rectifiers.

In Each Jackfield Cupboard Is A Meter That Enables The User To Check On Heater Voltage, Ht Voltage And Voltage At 3 Places In Each 806 Unit.

Stereo Loudspeaker Power Amplifier 10 Watt Valve

Talkback Mic Assembly

3 Band Eq Bass Treble And Six Band Selectable Mid-Range Boost.