Author Topic: 4k Maintenance plan and advice  (Read 968 times)

tko

  • Newbie
  • *
  • Posts: 26
  • Karma: +0/-0
4k Maintenance plan and advice
« on: December 16, 2018, 09:48:37 AM »
Hi all,

Thanks for a fantastic site and info, I've spent many hours reading other owners/users incredible journeys making cool alterations and owning the SSL DIY attitude!

I'm starting this thread to lean on all your amazing knowledge as I am located in NZ and there is literally NO SSL techs. I have a solid understanding of electronics and can solder. I've wired many studios and build a bunch of 1176's, mics and way too many bantam patch bays.

I have introduced my desk before but I'll go again - My SSL is the Ex-Real World 4k. It's a thing of beauty to me. It was cut down by Alan Smart to 24 and has been absolutely amazing to use, it's made a lot of albums and literally recorded hundreds of drums sessions and mixed over 1000 songs. I've tried mixing itb and I can't do it. I need to see 0dbvu and have those EQ's right there.

About 6-9 months ago I began to get some intermittent issues which have progressively gotten worse. EQs engaged killing channels or losing lows etc, compressors distorting, Channels returns with no signal etc.

I originally posted a Q here: http://forum.sslmixed.com/index.php/topic,1371.0.html

But after some research (on this site) I've decided that after almost 9yrs of every day use and no real maintenance (as none seemed to be required other than bulbs and scratchy switches) it's time look at all the faults and give my 4k a full overhaul and start a programme of maintenance for the long term, while making sure I am doing everything right to look after her. I have 6 weeks off with no sessions booked, so I'm going to get stuck into it. There are also some minor issues that have been there since I purchased which I want to fix too, no VU lamps work for example.

I'm initially looking for suggestions on things I should do that might fix any simple issues such as bad card seating or general tips that can be easy fixes. I think its good place to start this journey with. And also anything I should look out for on the channels.

Of note:

1. The desk was moved 2 yrs ago and the issues started a little after that. When I moved to the new location 2016 the movers lost the rear panels and I never thought much of it. But I actually just found them buried in my lock up. So if that has contributed to heat inconsistency please let me know. I do intend to put them back on with this work.
2. I have already ordered a full set up Caps from Recycled Audio (just incase) and enough LEDS to replace the cut/solo lights.

This is what I am considering so far:

3. I read on another thread (http://forum.sslmixed.com/index.php/topic,675.msg4547.html#msg4547) that suggested making an excel spreadsheet to document issues, so I can do that first.
4. I have 3 buckets so once all faults are documented power them down and one channel at a time remove all cards clean all cards connectors with Isopropyl, clean all switches with contact cleaner.
3. Re power up 1 bucket with my riser card re check documented issues and then come back to here for my next steps?

Thanks all for any help!

TKO - The Armoury - Wellington NZ.

P.S Here's a pic...

« Last Edit: December 16, 2018, 09:54:30 AM by tko »

amillar

  • Jr. Member
  • **
  • Posts: 73
  • Karma: +8/-0
    • United Kingdom
Re: 4k Maintenance plan and advice
« Reply #1 on: December 19, 2018, 01:39:47 PM »
What a fantastic post  :) Really hope you can get this desk back to top spec, absolutely no reason why you shouldn't be able to given enough time and effort.

A few thoughts (others with more experience of coping with old 4ks will have far more I'm sure!). Apologies if any of these seem really obvious - sometimes we all miss the really obvious...
  • Have you checked the power rails? Absolutely vital. There's instructions on a recent thread.
  • Don't worry about the back covers being on/off regarding temperature - when we final tested desks before shipping them to customers we never had the panels on (because you couldn't get to the desk and in case we accidentally scratched them). And if the air con breaks in the studio in summer it's best to take the covers off! But of course dust etc may well have got in while yours were off.
  • Even on brand new desks the card connectors - including 611 connectors - were not that great. ("Cheap" I think is the best word.) Hopefully someone here can recommend the best modern cleaning material for them, at SSL we used impregnated wipes called "gold wipes" but I've no idea who actually made these or if they are still available.
  • The 611 bus routing cards and EQ and dynamics cards are fine if they are not touched, but if they are removed (and possibly if they are shaken in transit) they can be a big source of intermittent connections. IIRC a VERY GENTLE squeeze with a pair of pliers of the connector pins helps. Tedious task! (At least you don't have plasma bargraphs...)


As you say, keeping a log of issues is vital. Because the routing in the channel and the whole desk is so complicated (that's what makes them great desks!) it's easy to believe a fault is in one part of the channel when it's actually somewhere else entirely. If you post the log up here we might be able to give a clue as to where else to look.

DEFINITELY make sure the power supply caps are ok, if they're dead the desk will do all sorts of strange things. I think probably the very first thing I'd do would be to unplug the supply form the desk, turn it on, turn it off again, and see how long it takes before the LEDS go off. Trouble is - it's so long since I last did that (probably 30 years) that I can't remember how long they should hold on for!

Again, good luck! If I think of anything else I'll add it.

Cheers,

Andy
co-designer and project manager G series analogue 1987
channel strip designer J series 1992-93
design "caretaker" 4000/6000 1985-93
analogue team leader ARC/Bertha 1988-92

tko

  • Newbie
  • *
  • Posts: 26
  • Karma: +0/-0
Re: 4k Maintenance plan and advice
« Reply #2 on: December 20, 2018, 09:14:45 AM »
@amillar Thank you so much for your time in replying and very grateful for sharing your knowledge/experience. Also thanks for being part of designing/building such an amazing console!

1. No I haven't checked the power rails - I will hunt that post down.
2. Thanks for the tip on the covers, I don't feel quite as guilty now. I will put them back on after I give the console a thorougher vacuum inside. I'm also looking at the air con and measures I can take to filter dust from entering the control room.
3. Deoxit Gold Wipes - of course! I used them growing up on boat electrical's. I've found it in a liquid form locally.
4. The 611 bus routing cards and EQ and dynamics cards are fine if they are not touched, but if they are removed (and possibly if they are shaken in transit) they can be a big source of intermittent connections. IIRC a VERY GENTLE squeeze with a pair of pliers of the connector pins helps. Tedious task! (At least you don't have plasma bargraphs...)

I think I understand this, but can't picture the actually pins in question unless you are talking about the buss routing cards?

The power supply trick and Caps. That's a fantastic tip! It never crossed my mind. Will do and repost. If someone knows the answer for the time pls let us know.

I have made a fault list and it's not that bad (it took a while!), but feels worse than it is because I tend to sub mix mostly in stereo pairs on the console so with 6 or so channels having issues thats almost half the desk when mixing in 12 stereo pairs on 24 channels.

I will do as I listed above with the addition of:

- Deoxit cleaner on all cards all EQ & Dynamics cards & 611 connecters (to motherboard)
- Tightening all bus routing cards

Thanks again and talk soon TKO.
« Last Edit: December 20, 2018, 09:16:35 AM by tko »

amillar

  • Jr. Member
  • **
  • Posts: 73
  • Karma: +8/-0
    • United Kingdom
Re: 4k Maintenance plan and advice
« Reply #3 on: December 20, 2018, 01:48:11 PM »
Sorry, meant to say "EQ and dynamics switch cards" - I think these also use the "forked pin" connectors? And the bus routing cards?

I keep meaning to ask here if anyone in the UK has a scrap 611 they'd be happy to donate to me - partly because I'd just like to have one after looking after them for so many years, and partly to help my memory in answering questions like this! I had one sitting next to my desk for years and years at SSL, but I was far too honest to take it with me when I left...I bet they just threw it in a skip anyway!

The power supply setup threads were very recent so should be easy to find, I posted the same info in both. Make sure you use a long screwdriver with a well insulated shaft when adjusting the PSU so you don't die!!!

Do let us know how you get on.


It's exciting working on plasma bargraph desks without the back covers on, one moment you're leaning casually on the back of the desk, next you're leaping in the air with your hair standing on end having had 250V dc applied somewhere painful! You have the right type of meter  :)

Cheers,

Andy

« Last Edit: December 20, 2018, 01:53:05 PM by amillar »
co-designer and project manager G series analogue 1987
channel strip designer J series 1992-93
design "caretaker" 4000/6000 1985-93
analogue team leader ARC/Bertha 1988-92

tko

  • Newbie
  • *
  • Posts: 26
  • Karma: +0/-0
Re: 4k Maintenance plan and advice
« Reply #4 on: December 21, 2018, 07:56:09 AM »
@amillar

- Thanks for the explanation on cards. I intend to pull the faulty cards and clean the connections and re-test anyway, so I'll make sure I re-seat them well. I may have to recap a few cards.
- Power supply LED fade with no load is about 2.5sec

Update:

- My full cap set is on it's way from Keith @ Recycled Audio
- I powered it down. Bucket at a time, then center section (first time in just over 2yrs) and did the power supply test
- I've pulled 16 channels out and begun the full clean
- It was pretty dusty, like I can write my name in the dust

Questions:

1. Is there a procedure for cleaning the receiving connectors on the motherboards for the 611's on the console, and on the 611's for daughter cards?
2. My oscillators are completely dead, where should I start with those?
3. I have a a few dead VU meters and 100% no lamps. I'll pull some out and try and fine one with a working bulb. But where should I start with that?

Thanks in advance for all your help and merry Xmas from NZ!

TKO - The Armoury.

tko

  • Newbie
  • *
  • Posts: 26
  • Karma: +0/-0
Re: 4k Maintenance plan and advice
« Reply #5 on: December 22, 2018, 11:38:52 PM »
Also:

I noticed on the power supply that the +250v & +20v LEDs are not on. This is when the console was unplugged.

Thanks TK

amillar

  • Jr. Member
  • **
  • Posts: 73
  • Karma: +8/-0
    • United Kingdom
Re: 4k Maintenance plan and advice
« Reply #6 on: December 23, 2018, 06:30:34 PM »
1. Is there a procedure for cleaning the receiving connectors on the motherboards for the 611's on the console, and on the 611's for daughter cards?
Hopefully someone else will come back with a tip here - it was never a problem on new consoles! Certainly very, very gently, better to not touch them at all than to risk bending / snapping the pins. I'd probably just start with a very soft paintbrush to clear the dust out.

2. My oscillators are completely dead, where should I start with those?
This is always a pain, I'll have a look at the circuits and get back to you (but probably not until after Christmas) if no-one else has any ideas. It's just one oscillator, so if it doesn't work none of the settings will work. When you know the power supplies are ok you could try taking the '34 card out of the 651 module and plugging it back in again.

3. I have a few dead VU meters and 100% no lamps. I'll pull some out and try and fine one with a working bulb. But where should I start with that?
For the dead ones swap the connections to the meters (IIRC the leads will reach) to see if it's the meter itself or the cable - it's probably more likely to be the cable. VU metering is very simple, there's practically nothing to go wrong. When you say "no lamps" do you mean no LEDs or no lights bulbs? I'm slightly puzzled as to why either wouldn't work across the whole desk. (Although again if you have no +18V you will have no lights!)

4. I noticed on the power supply that the +250v & +20v LEDs are not on.
250V will be off because you don't have bargraphs so the 250V card won't be fitted to your supply. So that's ok.
There is something odd about the interlinking between the +20V and the -20V (can't quite remember what) so it might be that, or it might just be a dead LED - what's more important is that you are getting +/-18V out of the "20V" supplies. If you actually aren't getting power out of the "+20V" (actually +18V) supply that would explain all your problems!!!

Sorry, I don't feel that's one of my most helpful replies!! If I get five minutes I will try to find out a bit more.

Good luck,

Andy
co-designer and project manager G series analogue 1987
channel strip designer J series 1992-93
design "caretaker" 4000/6000 1985-93
analogue team leader ARC/Bertha 1988-92

amillar

  • Jr. Member
  • **
  • Posts: 73
  • Karma: +8/-0
    • United Kingdom
Re: 4k Maintenance plan and advice
« Reply #7 on: December 23, 2018, 06:36:40 PM »
Just noticed something! If your desk has an 82E237 Buffered Meter board in the back of the desk - big board about the size of a laptop - it has four fuses on it (F1 to F4) in the 18V supply rails. Check those!

Cheers,

Andy
co-designer and project manager G series analogue 1987
channel strip designer J series 1992-93
design "caretaker" 4000/6000 1985-93
analogue team leader ARC/Bertha 1988-92

tko

  • Newbie
  • *
  • Posts: 26
  • Karma: +0/-0
Re: 4k Maintenance plan and advice
« Reply #8 on: January 09, 2019, 09:06:41 PM »
@amillar  - Thanks the F1 was blow. Would its specs be 18v and then the amps per the fuse? In this case 2amps.

Does anyone have any suggestions for fuses? The Meter supply fuses are proving hard to find to source for me.

Moving on:

I have hunted here but I can't find the threads on the power supplies, would someone kindly post a link?

Lastly can someone explain how you remove the VU lamps?

Thanks TK.
« Last Edit: January 10, 2019, 11:22:19 AM by tko »

waltzingbear

  • Sr. Member
  • ****
  • Posts: 270
  • Karma: +10/-0
    • Portland, Oregon
    • Waltzing Bear Audio
Re: 4k Maintenance plan and advice
« Reply #9 on: January 10, 2019, 06:40:50 PM »
as long as the voltage rating is above the actual usage voltage of the rail, it doesn't matter. In other words, you can use 120V or 250V 2A fuses.

Cheers
Alan
Alan Garren
Waltzing Bear Audio

tko

  • Newbie
  • *
  • Posts: 26
  • Karma: +0/-0
Re: 4k Maintenance plan and advice
« Reply #10 on: January 12, 2019, 07:36:43 AM »
THanks!

Have you ever replaced a lamp in a VU?

TK

waltzingbear

  • Sr. Member
  • ****
  • Posts: 270
  • Karma: +10/-0
    • Portland, Oregon
    • Waltzing Bear Audio
Re: 4k Maintenance plan and advice
« Reply #11 on: January 12, 2019, 06:06:15 PM »
yes, but I don't recall at all what the arrangement is like in the SSL

LED replacements are best, do it once and be done.  Putting individual LEDs and resistors in will not usually be satisfying as the light distribution is wrong. Paying for the already made substitutes is worth it.

Cheers
Alan
Alan Garren
Waltzing Bear Audio

xmax

  • Sr. Member
  • ****
  • Posts: 284
  • Karma: +10/-3
Re: 4k Maintenance plan and advice
« Reply #12 on: January 22, 2019, 03:50:06 PM »
I would say at least 80% of the problems I have solved with SSL (and most desks)
are capacitor and switch related, some switches can be cleaned with a contact cleaner
then lubricated with EML, Deoxit, Deoxid or Pro Gold, but a lot of times they need to
be replaced. A good desolder tool is a absolute must if you plan on doing your own
maintenance. Hakko 808 was my preferred tool, now the go to is the Hakko FR-300.
 However I recently bought a CSI 8900 desoldering pistol, as a back up and it works
very good for the cost (link below). 

A note on recapping I would highly recommend doing one card at a time, like the EQ
or dynamic card and testing the module after doing each card, if you create a problem
while recapping you will know what card needs to be double checked for polarity and
solder reflowed and look closely for accidental solder "bridges" or shorts.
Take your time use a well lit and ventilated space and have fun taking care of
your "baby"!

https://www.circuitspecialists.com/blackjack-solderwerks-bk3090-suction-gun-soldering-iron-combo.html


tko

  • Newbie
  • *
  • Posts: 26
  • Karma: +0/-0
Re: 4k Maintenance plan and advice
« Reply #13 on: February 07, 2019, 10:16:25 AM »
Hi all,

It's all well underway with the full recap, we are about halfway through and averaging 4 channels a day for the 2 of us. Testing as we go and actually fixing all other issues I had with the recapping alone!

I've found the desk is really coming to life and had no idea that recapping would improve the sound so much, so very excited about getting it completed.

I have Q before we move onto the 2 Bus.

My desk is a G+, on the CF82E26 - QB Mix Amp Patch Return VCA Compressor

1. C9 my cards have 47uf 16v, the schematic has 10u 50v
2. C5, C6, C11-C14, C29 & C30 all have a 22uf 35v, the schematic has 10u 35v

I checked all 4 cards and they are all the same, am I looking at standard G Schematics or have the wrong values been used. My Schematics are labelled Rev12 - July 89.

Lastly I don't use the monitoring selection on the SSL, I patch out to a Dangerous Monitor ST. So I don't want to recap cards I never use. So am I correct in thinking I only need to recap cards 25, 26 and 34 (to get my oscillators working). Everything else has been working fine and for now I'm needing to look at it ; Aux's, returns, t/b etc.

Thanks all and some pics attached.

TKO.


« Last Edit: February 07, 2019, 10:25:24 AM by tko »

waltzingbear

  • Sr. Member
  • ****
  • Posts: 270
  • Karma: +10/-0
    • Portland, Oregon
    • Waltzing Bear Audio
Re: 4k Maintenance plan and advice
« Reply #14 on: February 08, 2019, 07:16:25 PM »
Certainly you could not do the monitor section if you weren't going to use it. But you are being penny wise and pound foolish.

The monitor section allows you much greater access to signals within the board than just comparing the 2 buss and its return. Not having those available at the same level of confidence would be a mistake. Also when it comes time to replace this board (for what ever reason) it will not have been done. Its not that much more work and allows you a better picture of your ongoing work. Go ahead and use you Dangerous, but have the original monitor out appear there as well. Then All functions of the board are at your finger tips.

Using the slightly larger values will extend the low frequencies slightly (in theory) As they were apparently used as originally built, I would use the larger values. As today's caps are considerably smaller than the ones used at the time of the boards manufacture, you have the option to increase the voltage rating of the caps while maintaining the size. Electrolytic caps have better attributes at higher voltage ratings, so go with that. (within reason)

Cheers
Alan
Alan Garren
Waltzing Bear Audio