Neve schematic confusion

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noizetoys

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I have a copy of a Neve schematic for a monitor panel. I can understand what's going on (in most of it, it's an older workflow which can be somewhat confusing) but I was hoping someone might be able clarify how some things are being drawn.

This image shows the input transformer for the Monitor inputs. I wanted to make sure that the low side wasn't being tied to the shield. I don't think it is, I'm just wanting to double check. Would seem to go against the 'Neve Way' to tie the two together.

Neve  - Single input.jpg



The same thing is shown here on two inputs.

Neve  - Two inputs.jpg



As well as here, where there are two balanced inputs that are switched to a balanced output (at least I think they are, there are 3 wires after all)

Overdub Switch.jpg

I haven't seen this style on other schematics, that's why I'm asking.

Was Neve paying for blueprints by the line-inch? I don't think it's from laziness. Just a little confused why it would be drawn this way.

Thanks for looking.
 

abbey road d enfer

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Looks like someone was creative about schematic drawing, thinking drawing only one conductor in a pair was good enough.
Maybe Ian can shed some light.
 

ruffrecords

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This is just standard Neve two wire shorthand for balanced connections so you don't have to draw all three wires but it does show how all three are connected at both ends- think of it like a simple bus on a microprocessor schematic. All Neve balanced connections are floating . The low side is never connected to chassis/shield.

Hope that makes it clearer.

Cheers

Ian
 

noizetoys

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Thank you for your response. My suspicions were confirmed and my faith in Neve designs bolstered in the process!

Now, if I can just remember what all these lines mean! ;)
 

ruffrecords

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Now, if I can just remember what all these lines mean! ;)
Now that is a different question. The two wire was a manufacturing drawing that is meant to show how to wire it up rather than how it is supposed to work. The block diagram is the top level one that shows the signal flow from which you can deduce how it all works.

Cheers

Ian
 

noizetoys

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Thanks Ian!

I've puzzled out how it all works together. The only parts I found confusing were related to the 'Mono' section and the 'Input to Cues' section. Without knowing exactly how the monitor panel connected to the rest of the console it took a little longer to figure out.

Here's what the drawings showed:

- In the 'Mono' section, all 4 buses were summed (externally) with level control using the pot on the panel (again, connected externally) and could be sent to the any of four outputs of the quad bus. Interesting, but not terrible useful in modern workflows.

- The 'Inputs to Cues' takes two inputs and routes them to a single output. There are two outputs corresponding to four inputs. Where that goes, nobody knows. Maybe gets folded into the Input side Cues? I can only see the input and output pins of the Plessey connector.

- The whole 'Overdub' switch is a little odd. It sends either the 'OP' (Output) signal from an external source (the console channels or buses or whatever is patch in) or the 'PB' (playback) signal (from the 16 track I assume) and sends it out the pins labeled '16T' (16 track). '16T' looks like it was meant to be wired to an external transformer (to unbalance the signal) that then connected to the 'OverDub' input pins so it could be sent to the Cues? Again, it's a workflow thing.

My plan was to:
  • Split the input I was calling 'Overdub' (from the patch bay) by wiring two cables to the same pin. Nothing tricky.
    • One side of the split would go to a transformer connected to the 'Overdub' pins, giving me an additional 16 inputs. Yes, the 'Overdub' inputs only feed the 'Overdub to Cues' bus, but I was going to take the unbalanced outputs of the 'Overdub to Cues' summing amps and send them to either of the bus pairs (1/2 or 3/4).
    • The other side of the split would feed the 'IP' pins which connecting to the 'Overdub' button).
  • The 'PB' inputs (the other side of the 'Overdub' switch) are fed by DAW, tape, etc.
  • The output of the 'Overdub' switch would appear on the '16T' connector pins.
  • The '16T' pins would connect to Line Input transformers
  • The output of the transformers would feed the 'Monitor' input pins.

Or:

'Overdub' Connector -> Overdub Split 1 -> Line Transformer -> 'Overdub' pins
'Overdub' Connector -> Overdub Split 2 -> 'OP' Input pins -> 'Overdub' switch
'Monitor' Input connector -> 'PB' Input pins -> 'Overdub' switch

'Overdub' switch -> '16T' Output pins -> Line Transformer -> 'Monitor' input pins

Or something like that....
 

ruffrecords

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At the time that panel was designed, quadraphonics was the in thing but it was very short lived. Most radio and all TV in the UK was mono. Stereo record players were fairly common as were "radiograms". Very few people could play quad records. Cassettes were the new medium of choice and they were stereo only. The Walkman appeared in 1979. Bottom line is only a small number of quad consoles were ever built a Neve and every one was customised to the requirements of the particular studio and its workflow so it is not surprising it makes little sense.

Cheers

Ian
 

Matt Syson

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Apart from testing and commissioning desks at Audix I spent some time drawing the wiring details for MXT1000 desks and the 'single line for each signal' with the details shown at each 'end' was standard procedure, possibly because several of the engineers were Ex Neve, (before others then transferred to Neve, which was only 'just up the road'). The use of wiremen (and ladies) from companies supplying the MOD may have some 'input' too. Certainly the standard of wire looming and mechanical assembly work was very high.
Matt S
 

noizetoys

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Thanks for the responses.

Matt, I do have to say that the wiring and mechanics of the panel I have are excellent. Mine came unadulterated and very clean. I'm impressed by the consistency and quality of the wiring, labelling, and soldering. I can't imagine what this panel would have cost to build (parts and labor) but I'm sure it was much more than I paid for it (which was no small amount).

Thanks
 
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ruffrecords

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Apart from testing and commissioning desks at Audix I spent some time drawing the wiring details for MXT1000 desks and the 'single line for each signal' with the details shown at each 'end' was standard procedure, possibly because several of the engineers were Ex Neve, (before others then transferred to Neve, which was only 'just up the road'). The use of wiremen (and ladies) from companies supplying the MOD may have some 'input' too. Certainly the standard of wire looming and mechanical assembly work was very high.
Matt S
I agree. Before joining Neve I worked in the aerospace industry and this method of showing multi-cored screened cables was standard practice there also.

Cheers

Ian
 

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