Hi again Christian
There are a couple of obvious board-mods, no major changes or op-amp stuff though.
Until you've cleaned everything however, you won't know if they work or not.
Meantime...
...here's that lovely £60 diy mic-pre.
There has been loads said about it on the net; so see what people say.
Better still; just order a pair NOW, with your plastic.
Couple of hours soldering; gets you a valve based mic-pre with op-amp front-end; that you would be hard-pushed, not to know didn't cost $1000 ( serious ).
Probably wouldn't impress people much on gearslutz though.
Oh well; they won't be renting your studio; they'll be too busy waxing on about Neve & Manley; whilst having anxiety attacks about how much the latest video-bandwidth op-amp is going to set them back & how many pico-volts of noise reduction they MAY get ( if they fit it correctly, that is ! ).
Anyway; nuff ranting...
...here's the best upgrade since meths, pipe-cleaners & Lexicons ( whoops, I mentioned some gear; what a slut ! ).
Si.
There are a couple of obvious board-mods, no major changes or op-amp stuff though.
Until you've cleaned everything however, you won't know if they work or not.
Meantime...
...here's that lovely £60 diy mic-pre.
There has been loads said about it on the net; so see what people say.
Better still; just order a pair NOW, with your plastic.
Couple of hours soldering; gets you a valve based mic-pre with op-amp front-end; that you would be hard-pushed, not to know didn't cost $1000 ( serious ).
Probably wouldn't impress people much on gearslutz though.
Oh well; they won't be renting your studio; they'll be too busy waxing on about Neve & Manley; whilst having anxiety attacks about how much the latest video-bandwidth op-amp is going to set them back & how many pico-volts of noise reduction they MAY get ( if they fit it correctly, that is ! ).
Anyway; nuff ranting...
...here's the best upgrade since meths, pipe-cleaners & Lexicons ( whoops, I mentioned some gear; what a slut ! ).
Si.
Attachments
Hi Christian
Smart move on the self-built cables; shop stuff rubbish !
( clean the pins ! )
Personaly I would not track through the board further than a direct-out from the strips ( pre-EQ ).
That's just me though.
Record flat; EQ the mix.
Having reduced the massive potential noise from likely dirty contacts; you could try something on the board.
Not for noise reduction as such ( might help though ).
I would look at replacing components c1 c2 c7 c8 on the schematic; all of which are before the first op-amp.
I think after the big contact clean-up; you listen ( hopefully be TOTALY amazed ! ), and then do the strip-mod on 1 channel & listen to that.
See if it is noticable.
Components c1 & c2 block the 48 Volt phantom-power from getting to the first-stage ( leakey, noisey, electrolytics, not good ).
Any DC leaked through from phantom-power obviously makes the first transistor pair VERY UNHAPPY ( sob...sob...).
My thought is that the component value here ( I think it says 47uF on the schematic ) does not have to be this large a value.
10uF should be fine.
The schematic states c7 & c8 to be 10uF also.
I would replace all 4 of them with 10uF 63 Volt Polyester capacitors.
The orange-blob shape ones are great.
They come to this 10uF, in a very modest sized package.
Can be mounted slightly off-board on short insulated leads etc. if needed.
In the UK I would order CPC part # CA05390 about 1 euro each.
These are actualy 100 Volt, I am sure RS have similar in 63 Volt maybe.
I'm sure you know this component as lecey-guy, very easy to get & compact.
Op-amps.........Mmmmmmm
Si.
Smart move on the self-built cables; shop stuff rubbish !
( clean the pins ! )
Personaly I would not track through the board further than a direct-out from the strips ( pre-EQ ).
That's just me though.
Record flat; EQ the mix.
Having reduced the massive potential noise from likely dirty contacts; you could try something on the board.
Not for noise reduction as such ( might help though ).
I would look at replacing components c1 c2 c7 c8 on the schematic; all of which are before the first op-amp.
I think after the big contact clean-up; you listen ( hopefully be TOTALY amazed ! ), and then do the strip-mod on 1 channel & listen to that.
See if it is noticable.
Components c1 & c2 block the 48 Volt phantom-power from getting to the first-stage ( leakey, noisey, electrolytics, not good ).
Any DC leaked through from phantom-power obviously makes the first transistor pair VERY UNHAPPY ( sob...sob...).
My thought is that the component value here ( I think it says 47uF on the schematic ) does not have to be this large a value.
10uF should be fine.
The schematic states c7 & c8 to be 10uF also.
I would replace all 4 of them with 10uF 63 Volt Polyester capacitors.
The orange-blob shape ones are great.
They come to this 10uF, in a very modest sized package.
Can be mounted slightly off-board on short insulated leads etc. if needed.
In the UK I would order CPC part # CA05390 about 1 euro each.
These are actualy 100 Volt, I am sure RS have similar in 63 Volt maybe.
I'm sure you know this component as lecey-guy, very easy to get & compact.
Op-amps.........Mmmmmmm
Si.
Christian.
Go to PAiA Corporation - Analog Synths, Theremins, Preamps, and More ( a USA based company ).
They have everything for about 60 euro's.
Inc skts, valve etc. etc.
Comes with PCB.
They do not sell PCB's alone.
I would throw some 'trick parts' at it myself ( it is worth it )...
...but the unit works great, as is, simples...
Also some component matching as well..
You could buy a pair to test ( great for precision mid-side etc.)...
...then copy the board youself.
As said the Gyraf G9 'all-tube' mic-pre is well worth checking out.
Strangely enough....I'm building one at the moment !!!!!!
There is however no kit available.
There is a PCB though.
But I hear it has 'issues'.
Personaly I am P2P on the Gyraf G9.
The design is WAY more complex than the Paia.
And WAY more expensive; by a VERY large factor.
I am hopeing for good things from the Gyraf G9...
...but honestly...in a blind AB test...
...I do not think one would sound BETTER than the other; just DIFFERENT.
Nice Danish chap the Gyraf designer...
...bung some Lundahls in...BINGO
Back to ye olde days.
Si.
Go to PAiA Corporation - Analog Synths, Theremins, Preamps, and More ( a USA based company ).
They have everything for about 60 euro's.
Inc skts, valve etc. etc.
Comes with PCB.
They do not sell PCB's alone.
I would throw some 'trick parts' at it myself ( it is worth it )...
...but the unit works great, as is, simples...
Also some component matching as well..
You could buy a pair to test ( great for precision mid-side etc.)...
...then copy the board youself.
As said the Gyraf G9 'all-tube' mic-pre is well worth checking out.
Strangely enough....I'm building one at the moment !!!!!!
There is however no kit available.
There is a PCB though.
But I hear it has 'issues'.
Personaly I am P2P on the Gyraf G9.
The design is WAY more complex than the Paia.
And WAY more expensive; by a VERY large factor.
I am hopeing for good things from the Gyraf G9...
...but honestly...in a blind AB test...
...I do not think one would sound BETTER than the other; just DIFFERENT.
Nice Danish chap the Gyraf designer...
...bung some Lundahls in...BINGO
Back to ye olde days.
Si.
Of course the other obvious thing to do is...
...Just get rid of the phantom-power blocking capacitors c1 & c2 altogether...
...and replace them with an input transformer.
Benifits :-
No input capacitors before your first gain stage.
RF effectivley blocked from saturating the first sensitive gain transistors.
FREE GAIN !!! ( can't be a bad thing ).
Could try a modest 1:2 or 1:3
Thus backing off the mic-gain control & getting much less noise.
Don't forget also...
...all your inputs don't have to be the same, like a factory board.
Transformer inputs for your best ( probably less output ) mics.
Cheap transformer inputs for your next best, etc etc.
Can fit them one at a time and check brands & results as you see fit.
Still replace c7 & c8 as well.
When the transistor came along, input transformers were dropped from most ( affordable ) desks.
This MAY have not been such an issue way back when...
...but these days, particularly with the cell-phone density the way it is...
...need I say more.
Si.
I have used cheap OEP transformers from RS etc.
And expensive Lundahl's from the even more expensive Canford Audio.
You do get what you pay for though.
The main point being, the lower the resistance of the windings; the less noise.
More wire, bigger wire, bigger transformer, more expensive transformer.
Best spec. to look for ???
Pretty much just buy 'em by weight !!!
...Just get rid of the phantom-power blocking capacitors c1 & c2 altogether...
...and replace them with an input transformer.
Benifits :-
No input capacitors before your first gain stage.
RF effectivley blocked from saturating the first sensitive gain transistors.
FREE GAIN !!! ( can't be a bad thing ).
Could try a modest 1:2 or 1:3
Thus backing off the mic-gain control & getting much less noise.
Don't forget also...
...all your inputs don't have to be the same, like a factory board.
Transformer inputs for your best ( probably less output ) mics.
Cheap transformer inputs for your next best, etc etc.
Can fit them one at a time and check brands & results as you see fit.
Still replace c7 & c8 as well.
When the transistor came along, input transformers were dropped from most ( affordable ) desks.
This MAY have not been such an issue way back when...
...but these days, particularly with the cell-phone density the way it is...
...need I say more.
Si.
I have used cheap OEP transformers from RS etc.
And expensive Lundahl's from the even more expensive Canford Audio.
You do get what you pay for though.
The main point being, the lower the resistance of the windings; the less noise.
More wire, bigger wire, bigger transformer, more expensive transformer.
Best spec. to look for ???
Pretty much just buy 'em by weight !!!
My assistant and I were in the studio this evening cleaning all connectors out. We need a few of the loose microphone cables, but all connectors on the Soundcraft are cleaned thorougly. Next step is recapping the console, which I will start doing on monday when I receive the caps in the mail.
I am looking at eBay for input transformers, waiting for a good deal, then I will modify some of the channels to be transformer coupled, and maybe use some transformers to build some valve mic pre's. I have a bunch of old Philips SQ-40 high-voltage (100V) amplifiers, where the cabinets/cases/whatever they are called, will be excellent for making some "vintage" looking tube preamps. They also have some components I can reuse for the project.
I am looking at eBay for input transformers, waiting for a good deal, then I will modify some of the channels to be transformer coupled, and maybe use some transformers to build some valve mic pre's. I have a bunch of old Philips SQ-40 high-voltage (100V) amplifiers, where the cabinets/cases/whatever they are called, will be excellent for making some "vintage" looking tube preamps. They also have some components I can reuse for the project.
It is an 800B, but the basic design is the same. I have relocated the studio and the 800B has been retired, and will be up for sale. It is being replaced with a Soundtracs Quartz 32 channel
I did try various things, I did not try transformers however. First of all, I replaced all electrolytic capacitors with newer low-ESR devices. I replaced the coupling capacitors with at least 5 times the value of the originals. This tightened up the bottom end a bit, but was not night and day.
I also took a whole channel strip and replaced all the original opamps (TL072, NE5532) with high performance opamps. In my opinion NOT worth it. I couldn't notice any significant difference between two channel strips, one with original opamps, and one with the high perf. Noise floor was basically the same as well.
What actually helped most was a thorough cleaning of ALL contacts, connectors, etc. Start with the XLR and jacks on the back. Use one of those sets with round metal brushes that will go INTO the plugs. Use some contact cleaner. Then clean the internal connectors, pots and switches. Especially the switches can get dirty, leading to scratching sounds, intermittent connection and noise and distortion.
The thing that made most difference was the cleaning. Even though my 800B had been cared for properly (looked clean and without scratches) and very few of the pots were scratchy, it was still a good "upgrade"
It will not take that long, and it is definitely cheaper than replacing opamps, and doing other mods.
BRILLIANT~! And thanks SO much for this.
This is a verification and justification of Back to the Basics.
Cleaning all contacts and connections is THE Foundation of good audio.
Start with a (reasonably) well designed console and give it a good thorough cleaning, bringing it back as close as possible to original specs / operation and this will be at least as valuable as all the cork sniffing "high end mods" that are meant to hotrod an already great console.
Not to say that improvements cannot be made by spending much more time and money, but are those (last 1 or 2% of) results really worth all of that to you? As many will say, there are other places in the recording chain where those efforts may give a lot more of a payoff.
I am in a similar situation with a gorgeous Soundcraft Delta 8 console that was obviously very well professionally cared for.
After much research and reading of various advice and forums, what was just written in this recent post will be my guideline for "mods" and upgrades.
A few years ago I purchased a Soundcraft 600 Series board from an engineer / producer / musician who had worked at many of the pro studios in and around Manhattan.
Asking him about any mods or upgrades to the board, he had this to say;
Never did any. The designers of these consoles were some very bright engineers and created these mixers to sound really good when new.
While working in lots of studios with many other much higher end boards, I can easily say that the 600 Series is a very good sounding console.
Obviously it all depends on what one is looking to accomplish, but there have been plenty of brilliant record albums created on a lot less (not that this is an excuse not to use the best that you can),
The Basics will always hold true.
A good, clean signal chain makes for the best audio and dirty contacts and connections (OR miles of cabling between equipment and patch bays) can degrade audio in even the the best of components.
Thanks again for your post.
Thanks so much for the update!
Great input. I am starting with the cleaning side (knobs, pots, switches, faders, contacts) and the chassis rust.
I have been hesitant to buy into the IC swapping, but will be re-capping some channels for sure to listen for the difference before proceeding.
As for mods, I like the idea of having different colors, and since there are 32 channels, i can get away with having 8 channels being mod'd up, some with transformers, maybe even using DOA's on a couple channels if i can fit them in.
I do hear great things about the Ciletti grounding mod, but in reality, this board is already amazingly quiet. I did my first recordings with it last night using 2 channels to mic up a piano and didn't hear any noticeable noise on the playback. Dang those pre's sound good!
Thanks again for the info.
Great input. I am starting with the cleaning side (knobs, pots, switches, faders, contacts) and the chassis rust.
I have been hesitant to buy into the IC swapping, but will be re-capping some channels for sure to listen for the difference before proceeding.
As for mods, I like the idea of having different colors, and since there are 32 channels, i can get away with having 8 channels being mod'd up, some with transformers, maybe even using DOA's on a couple channels if i can fit them in.
I do hear great things about the Ciletti grounding mod, but in reality, this board is already amazingly quiet. I did my first recordings with it last night using 2 channels to mic up a piano and didn't hear any noticeable noise on the playback. Dang those pre's sound good!
Thanks again for the info.
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