Archive for Neve

Calrec PQ 1161 Mic Pre & EQs

Posted in Repaired with tags , , , , , , , , , on September 29, 2013 by AnalogAudioRepair

I have always been interested in Calrec modules.  They are touted as being “as good as Neve”, “built to BBC specs”, and on and on.  Recently I found myself with a few modules on my bench from two different clients.  The first two were racked and powered but the second unit was noisy.  The other module came from a larger rack with 1181 and 1161 modules.  It had a different problem which I will get to later.  Besides the beautiful construction of these units, the first big thing I noticed was that the pair had all discrete amplifier cards, while the single unit had ICs (chips) on the cards!  It seems Calrec changed over at some point between the serial numbers in the 450 range and those in the 600 range.

The discrete amplifier cards are easy to pull out and swap for quick troubleshooting.  That was good because it allowed me to pinpoint the output amplifier as the noisy board.  Then probing with the oscilloscope tracked the noise down to the first transistor on the card.  Replaced the part, and it spec’ed just like the good channel again.

Thankfully the module with ICs had a much simpler problem, though one to watch out for!  These modules were sold with no light bulbs in the EQ and phase reverse switches.  The owner bought bulbs, put one in the EQ switch and watched smoke come pouring out!  Fearing the worst, he brought me the module.  Thankfully, there is a current limiting resistor which gave it’s life (and gave up the magic smoke) to save the day.  The problem was the way that the bulb socket mounts on the switch.  It is a plastic holder that straddles the switch and is soldered to the first pin on either side.  However, on this one module the other pins were not bent down for some reason (as they were on all the other modules) so pushing in the bulb caused it to short against the second pin!  Replacing the 100 ohm resistor and bending the pins was all it took to get things back to normal.

Image

Calrec PQ 1161 Preamp & EQ

Calrec PQ 1161 Preamp & EQ

Calrec chip amplifier cards B202/205/210

Calrec chip amplifier cards B202/205/210

Calrec chip amplifier cards B202/205/210

Calrec chip amplifier cards B202/205/210

Calrec discrete amplifier cards B202/205/210

Calrec discrete amplifier cards B202/205/210

Calrec discrete amplifier cards B202/205/210

Calrec discrete amplifier cards B202/205/210

Calrec discrete amplifier card B202/205/210 PCB Front

Calrec discrete amplifier card B202/205/210 PCB Front

Calrec discrete amplifier card B202/205/210 PCB Back

Calrec discrete amplifier card B202/205/210 PCB Back

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Neve 5316 Diagrams

Posted in Uncategorized with tags , , , , , , , , , , , on July 21, 2013 by AnalogAudioRepair

I have been working on some modifications to the Studio G Neve 5316.  The board came from BBC Scotland and did not have any schematics.  While it is certainly possible to figure out a lot of the signal flow without block diagrams, it is sort of like driving across country without a map – you know where you start and end, but you have to find signs in between.

I posted on Geoff Tanner’s vintage Neve forum at http://auroraaudio.net/forums/ and frequent contributor Mr. Blake Devitt was able to provide some helpful documents.  The forum did not handle large images well, so I volunteered to host them here for anyone who needs them in the future.

Block Diagram

Block Diagram

Circuit page 1

Circuit page 1

System Diagram

System Diagram

Neve 5442 Mixer

Posted in Repaired with tags , , , , , , , , , , on August 5, 2012 by AnalogAudioRepair

Neve 5442 8×2 Mixing Board.  Built custom power supply and replaced failed tantalum caps.