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Old 8th October 2012, 10:24 AM   #31
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Have you got a decent copy of the input schematic ?

Section A - E is cut-out & not shown.

Just the stuff up to the first Op Amp.

Cheers

Si.

PS. give up gearslutz, it seriously damages your health ( read, brain & wallet ).

Nothing wrong with 5532 Ops or Texas 071...

...lovely little bugs !!!
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Old 8th October 2012, 11:02 AM   #32
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Quote:
Originally Posted by The Space Egg Corp View Post
Have you got a decent copy of the input schematic ?

Section A - E is cut-out & not shown.

Just the stuff up to the first Op Amp.

Cheers

Si.

PS. give up gearslutz, it seriously damages your health ( read, brain & wallet ).

Nothing wrong with 5532 Ops or Texas 071...

...lovely little bugs !!!
I have linked to the complete schematics in the second post. The schematic for the whole input module is found on page 4. My modules are not completely identical, since they don't have the line in, but instead have 8 aux send pots, otherwise the circuits are completely identical.
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Old 8th October 2012, 11:18 AM   #33
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Hi ronne

Got a couple of ideas for you.
Just looking for a pic to post.

Have you cleaned the input XLR sockets ?
Have you measured the output voltage of the phantom power at the XLR input sockets ?
How many & what mics do you normaly use recording a band ?

Si.
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Old 8th October 2012, 12:01 PM   #34
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Yeah...I know you linked it in the 2nd post...I looked at the partial circuit.
I have cell-phone internet...
...& unfortunatly downloading a gazzilion terra-bytes of Soundcraft PDF's & chopping bits out of them is not on the cards.
Just wondered, since you already have it...if it was easy to post a complette front end.

Si.
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Old 8th October 2012, 01:07 PM   #35
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Here is the complete (well almost) schematic of the channel strip.

I have not cleaned the XLR inputs, good idea, will do that.
I have not measured the phantom power output, will do that too

I normally use loads of microphones when recording. It is not unusual to have 14-18 mics just for the drum kit.
For kick drum I usually use a AKG D112, Beta 52A and a home made subkick. Snare gets a Sennheiser MD421 or Beyer M201 on top and a SM57 or Small Diaphragm Condenser on the bottom. For HiHats i use Røde M3, and either MD421, SM57 Beyer Soundstar (similar to MD421) or Shure PG56 for toms, depending on which I don't use on the other drums. For OH I use Groove Tubes Convertible and sometimes I throw my Neumann U87 for room, or ride cymbal whichever one is important. I often borrow a stereo set of AKG C-414 for room/ambience.

The rest of the instruments use the same pool of microphones (SM57, MD421, U87 and so on) depending on requirements and whatever sounds good.
It's not unusual for me to use two or three microphones on a guitar cab and then blend to taste.
Attached Images
File Type: png soundcraft.png (152.2 KB, 94 views)
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Old 8th October 2012, 05:18 PM   #36
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Hi Ronne

Thanks for the diagram.
Just grabbed some shut-eye...back now.

Thanks for the mic info.
It just gives a quick picture as to what you're doing there.
Nice mics, nice technique ( I'm sure you already know that though ! ).

I have got several more ideas you could try ( none involve op-amps !!!!! ).
To me they are the most obvious way to, incrementaly; hopefully raise the 'sonic' quality of what you have already ( which I'm sure is basicaly good ).

Where are you by the way ? ( Ronne ? ).
Is your studio in a large built-up area ?
ie. lots of cell-phones, mini-cab radios, industrial-motors & the-like around.
Or a country-mile from the nearest signs of life.
( I suspect the former; just a guess though )

Coffee is made !!!
Back in a bit.

Si.

You could have a few ( depends on budget ) extra pre-amps, as well.
Nice to know you're not afraid of soldering.
How about a top-notch mic-pre for £60 and 2 or 3 hours to solder it together ???

Net result is; you can reduce the gain somewhat on the board itself...BINGO...
Perhaps just a few to start with; for your overheads & condensers.
Nice !
Tube-pre as well !!!
With nice dial-able 'valve sound'...
Blues & jazzers gonna love 'em...
...dunno about the metal-boyz though.
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Old 8th October 2012, 05:48 PM   #37
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Quote:
Originally Posted by The Space Egg Corp View Post
Hi Ronne

Thanks for the diagram.
Just grabbed some shut-eye...back now.

Thanks for the mic info.
It just gives a quick picture as to what you're doing there.
Nice mics, nice technique ( I'm sure you already know that though ! ).

I have got several more ideas you could try ( none involve op-amps !!!!! ).
To me they are the most obvious way to, incrementaly; hopefully raise the 'sonic' quality of what you have already ( which I'm sure is basicaly good ).

Where are you by the way ? ( Ronne ? ).
Is your studio in a large built-up area ?
ie. lots of cell-phones, mini-cab radios, industrial-motors & the-like around.
Or a country-mile from the nearest signs of life.
( I suspect the former; just a guess though )

Coffee is made !!!
Back in a bit.

Si.

You could have a few ( depends on budget ) extra pre-amps, as well.
Nice to know you're not afraid of soldering.
How about a top-notch mic-pre for £60 and 2 or 3 hours to solder it together ???

Net result is; you can reduce the gain somewhat on the board itself...BINGO...
Perhaps just a few to start with; for your overheads & condensers.
Nice !
Tube-pre as well !!!
With nice dial-able 'valve sound'...
Blues & jazzers gonna love 'em...
...dunno about the metal-boyz though.
Well, my real name is Christian, the Ronned2tm is a longer story, not really interesting
The studio is placed in Denmark in a city called Esbjerg. The neigbourhood is mixed industrial and residential. I could suspect that there might be som RF interference, but since the control room itself is placed inside an old bank deposit box, where cell phone reception is very problematic, I would only suspect that the signal lines from the different rooms in the studio might be possible suspects of RF interference.

I have recorded a bunch of stuff already, mostly rock and a couple of jazz tunes, with excellent results, though I know there is room for improvement.
The obvious no-brainer would be to buy some nice external preamps, but I am willing to do DIY if there is money to save. I already own equipment and parts for building various stuff, valve stuff too. I have a quite large stock of valves, (100+) both used, new and NOS. I also have access to PCB production via my work and have several years of experience with soldering and electronics fault finding, since I am educated as an electronics technician. I do it for a living

Could you link to some schematics for nice preamps? I would be very interested in making some, if it can be done relatively cheap. If I understand you correctly, there is not much to do inside the console?

Coffee is nice! I'm having a cup right now
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Old 8th October 2012, 07:01 PM   #38
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Hi Christian

Yes ...a couple of console mod ideas to follow.

The mic-pre mentioned for £60....
...dunno what the euro's doing at the moment...but read that as 60 euro's ( ish )...
...All components, PCB, pots, sockets, valve & holder, all included in the price...
...individual phantom-power supply on each board...
...individual local regulation on each board...

All you need is a case & a transformer, rectifier & large filter caps in an external PSU; to power as many as you want.
I would buy 2 to start with.
See if you like 'em ( you will ).
Could put a whole bunch of 'em in a 2u or 3u case ( VERO 2u / 3u ventilated rack case, farnell.com CHEAP & good case ! ).

Schematics & more to follow ...
Another coffee needed...
Am S L O W typer

Si.
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Old 8th October 2012, 08:13 PM   #39
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Hi again Christian

The most significant studio upgrade you will ever make is...
...a bottle of meths & a load of pipe-cleaners & rag...
...cost...2 euro's.

Clean the mic pins
Clean the mic lead XLR's
Clean the board XLR sockets
Clean the phantom-power switch
Clean the pad switch

When you think you've cleaned them enough...
...start again, with new pipe-cleaners & rag...
...and do it AGAIN !!!

Got the message ?

You could at this point add some fancy 'Hi-Fi' Deox-It fluid...
...I think a product called INOX is cheaper though.
( people clean their slot-car race tracks with it ( I like slot-car race tracks !!! ))

Next...
...pull the modules on the board & do the same.
In fact, anything that comes off the main-frame; pull it & CLEAN IT !!!

Then the guitar gear ( more low-level signals getting screwed ).
Then your jack-fields.
Then your outboard.
Then your recorder.

Etc. etc. etc.

Also while you have the board apart...
...hoover & dust it out.
Blocked ventilation holes & dust = heat build-up = noise.

More to follow...

Si.

What recorder do you use ?
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Old 8th October 2012, 08:31 PM   #40
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Well, the guts of the Soundcraft has already been thoroughly cleaned, though I haven't cleaned the XLR and Jack sockets. I will do that, and maybe get my assistant to help me. Luckily there is not a single scratchy pot in the console. Never given the microphones a thought but it does make sense to me that cleaning all contacts would be a good idea.
I mostly record to digital via three Presonus FirePod totalling to 24 channels of simultaneous recording. Around half of the times I use the board for mixing/summing, and the other half, I mix in the box, but tracking is of course always through the console when I do it in-house. Occasionally when I'm mixing through the board, I mix down to tape (Studer B67, just recently acquired and completely restored, very nice and warm full sound) and back into the computer just to get the tape warmth onto the track, befor sending of to mastering or doing mastering myself. I do have a plan at some point to invest in an analogue multitrack recorder (preferably 2") so that my studio has the option to make a complete analogue record, if a client want that.

All of the cables in the fixed installations is of high quality, properly screened, and the loose cables used in the studio are all of high quality cable with either Switchcraft or Neutrik connectors, all soldered by myself using a good solderng iron and solder, guaranteed no cold joints.

Thank you for taking your time to give me some advice. Though unlikely to happen, if you're ever in Denmark, particulary around the west coast city Esbjerg (actually where the ships from the UK sail from) you are more than welcome to visit me at the studio and have cup or ten of coffee.
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