Servicing the Soundcraft Ghost part 2

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9 жыл бұрын

Part 2 in a 2 part tutorial by Richard Zeier about servicing the Soundcraft Ghost console. Richard is an experienced studio tech and former console builder for Neotek. His resume' also includes extensive work with Soundcraft, Neve, and Trident consoles, as well as audio product design.

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@tomdial2941 3 жыл бұрын

Richard, what a fantastic series of videos on repairing the Ghost! Thanks for taking the time to put this on KZfaq. It's a great help to me as I consider whether or not I want to purchase on myself.

@havelockchristianchurch8477 7 жыл бұрын

Thanks Richard!! Helpful indeed. Appreciate your efforts in teaching here.

@RichardZeier 9 жыл бұрын

Hi Chris, That's a great suggestion. I tried answering your questions with a post and started writing a book. I have a lot of information to share on power supplies and grounding and how to determine if the noise is from the console or an external source. I also have a method for finding and isolating console noise sources like rogue opamps that doesn't require any special equipment. And I would love to talk about console design, proper gain staging and signal to noise optimization. I'm currently pretty busy, but I'm placing this on my list of things to do. Thanks for asking. Richard

@zimcricket 9 жыл бұрын

Hey Richard- Just saw your response- I would read that book! I'm going a little crazy trying to figure out what is reasonable to expect from the board or from my comps or reverbs, etc, noise-wise. All of my analog gear is 20 or 30 or 40 years old. I have scored a beefed up acopian power supply for the Ghost that has given me WAY more headroom than i had, but the buzz is the same. But i think ( if i have the reference levels set properly- which is also a question) that the -80db noise level is normal according to the manual- (if i'm reading the manual properly!) Anyway- thanks. I look forward to whatever video you choose to do next chris

@RichardZeier 9 жыл бұрын

Chris Zimmerman Hey Chris, The first thing I do when setting up a console for the first time is make sure the studio has a good electrical and audio ground. If you are getting a lot of 60 cycle buzz it is most likely related to a grounding issue. If possible, depending on the location, I like to create my own audio ground that is isolated from the electrical grid. This usually requires driving a 10 copper rod nearby and using isolated ground electrical outlets the make use of the audio ground for the entire studio. I had a friend who is an electrician help out with pulling wires in my studio but your average electrician will have no knowledge about audio grounding techniques. I can turn my monitor pot all the way up (enough to vaporize my speakers with normal signal) and hear a little hiss but no buzz.

@RocketRaven 9 жыл бұрын

Richard Zeier what kind of brush do you use to clean it?

@RichardZeier 9 жыл бұрын

if you're asking about cleaning circuit boards, a small still paint brush with some acetone works well. Also denatured alcohol with Q-tips can be useful. There are various Deoxit products I would recommend for cleaning switches and pots.

@RocketRaven 9 жыл бұрын

thanks :)

@chieflongfeather 5 жыл бұрын

love your video. i like to know far as you cap mod.what did you replace the small 47uf cap value with?

@RichardZeier 9 жыл бұрын

You are very welcome. I have a PSM-300 power supply that is made for a slightly larger console, and I probably should have taken before and after current measurements, but didn't, so unfortunately can't give you a definite answer. However, it should not have been too significant considering the opamp changes. I only modified 12 of the mic pres requiring one OPA2134 replacing a TL072 for a net gain of 5mA per module (60mA total). Most of the opamp changes were NE5532 to LM4562, and the 5532s are current hogs to start with so only slight increase there, and I only replaced the ones in critical paths to suit my needs, so not all channels were treated equally. The first 12 channels got "the works" because I use them for tracking. Every other channel just got upgraded Tape Returns and Fader Buffers for Out-of-the-Box mixing to the B Mix Bus. The NE5532s in the Master section were replaced with some 4562s and some OPA1612s that actually draw less current. I didn't change the value of the power rail caps, just better quality. Those are the ones that surge the most on power up and will kill your supply. The oversized audio caps are used to block DC and pass audio and are not a factor in current consumption. Since there is no way to do an objective before and after A/B listening test, I can only tell you that the console sounds great. The lower noise is probably the most noticeable and measurable result. I love transformers, and design products with them. The console isn't open now, but it seems like limited space. It might be easier to connect them externally, but if you're determined, I'm sure it could be done.

@RichardZeier 9 жыл бұрын

I checked out your Ghost in action video and really enjoyed the awesome music. Is that you're guitar work? It looks like you're mixing through the desk to tape. Very cool. I can see where the mods might be a bit much for most Ghost owners. It's always a balance of resources. Cheers *****

@matti8717 6 жыл бұрын

Awesome video, could you please share that what Neutrik Jacks did you use on the inserts? Mine are starting to give troubles so definitely need to replace them. Thank you! -Matt

@RichardZeier 6 жыл бұрын

Hi Matti, All of the 1/4" jacks are the same TRS connector whether balanced or not. The Neutrik part # is NMJ6HCD2. This is an upgrade from the original Rean jacks.

@zimcricket 9 жыл бұрын

Thanks for these great videos! Super helpful. Not sure if you do requests. but... "FREEBIRD!" Just kidding.... I sort of have a request for a new video... I've been trying to troubleshoot noise in the studio and want to know what the Ghost should be expected to sound like. Any chance you could demo the noise floor of your Ghost? I have no idea what kind of noise floor I should expect from the Ghost. I know what mine sounds like when I bus all the channels... It's slight, but it's mix of hum and buzz (and hiss if the channel faders are up) Maybe you could talk about which components affect which part of the noise. I have everything unplugged from the Ghost except a pair of headphones. So I'm curious about the self noise or the RF, etc Thanks again for all the time you've already generously given. Very cool.

@Munatix Жыл бұрын

Hi Richard, great video's on the Soundcraft Ghost! We are experiencing crackling on different channels of our unit, because of bad contacts. It is getting worse over the years. I have now 6 channels in that state that are not usable anymore. The problem is separate from the headpohne plug problem. The problem manifests itself by cracling and intermittent sound. Can you tell from experience where most probably the bad contacts are situated in these channels? I have no hinges installed in the unit. So I want to be well prepared when I open it up, so I have everything at hand.

@RichardZeier Жыл бұрын

Hi Munatix, Without actually being there, I can give you common faults to look for. You say its not the "headphone plug problem", I'm going to assume you mean the channel insert jack that can become intermittent and can be addressed without having to open the console. The other 2 most common failures are pots and switches, both of which can be verified and often temporarily remedied by exercising (not exorcising) them. One pot that I have found particularly menacing is the Tape Trim. Over time, the Tape Trim pot can have either it's track become contaminated or the wiper spring becomes weakened, either of which can cause it's resistance to fluctuate. Because this pot is in a feedback loop, these small fluctuations become amplified into hissing, popping and crackling sounds. Usually, if you turn the pot just a bit the sound will stop temporarily, but never for good. The best solution is to replace the pot, unfortunately, you need to find a pot to replace it with. I personally contemplated bypassing the pots, since I hardly ever use them. The plan was to remove the pot and place fixed resistors in the vacated holes that would give me precisely unity gain. In a way this would be an improvement because the pots tend to vary + or - 2dB when in the detent position. However, I didn't want to leave empty holes in the console and was able to find some pots on eBay that were almost identical with the exception of being 10K instead of 20K. This necessitated replacing R28 with a 5K49 resistor to provide unity gain at the detent position. I hope that's helpful. Richard

@franksanta9826 3 жыл бұрын

Hi Richard! Thank you very much for these videos, one question please, I have a spirit studio, and I ask if the mod for balanced direct outputs can also be done on the spirit studio console and what would be the resistance value. Thank you very much for your time Cheers

@RichardZeier 3 жыл бұрын

Hi Frank, I'm not really familiar with the Spirit Studio, but the balanced direct output mod (sometimes called "pseudo balanced") can be added to most consoles. How you actually implement it depends entirely on the construction of the console. The resistor in question is the same value as the output resistor on the opamp driving the output (typically 47, 50, 75 ohms). It's important to use 1% resistors to achieve the highest CMRR.

@franksanta9826 3 жыл бұрын

@@RichardZeier Hi Richard! thank you so much for you answer, very hepful

@Truckguy1970 4 жыл бұрын

Could you buy a couple of spare boards and when you have an issue just swap out the board and then repair the one that was taken out?

@RichardZeier 4 жыл бұрын

Hey Truckguy, Back in the day when I was doing studio tech work, most studios with a big board would keep spare modules on hand. Some like the Neve consoles could hot-swap modules in the middle of a session by loosening a couple screws and lifting the problem child out, and then slapping in a working spare. These consoles, were typically north of $200k, but you get what you pay for (sometimes). Neotek made a console at one time with similar type connectors, however, the connectors proved to cause more problems than module failures so they were short lived. The later Neotek, Soundcraft, and others in that class normally required a tech to change the modules, but it was still relatively simple, especially if you had a spare module on hand. Now lets talk about the Ghost; If you've watched the video then you know how difficult it is to remove a module. For me, I would take the bad module to the bench and repair it, and then put it back. While I had the console open, I would also take care of any other nagging problems right then because I don't wanna open this beast again anytime soon. That said, not everyone can easily make module repairs, nor do they have a bench with a test harness to test modules. In that case maybe it makes sense to have a couple spares if you can find some known working ones. I haven't looked for any but I'm sure there are people canabalizing old Ghosts and selling the parts. The problem is they need to be tested before you go to the trouble of installing them. I've thought about having a few spares for experimentation purposes. If you see any cheap ones let me know. Richard

@youvsyou945 7 жыл бұрын

Thanks for the awesome video! Do you like to use 60/40 solder for your repairs?

@RichardZeier 7 жыл бұрын

60/40 solder is fine, but more likely 63/37 these days. It's probably more important to have several sizes of solder available for various jobs (.032, .025, .020) and various size soldering iron tips and de-soldering tips. Good tools and careful work go a long way for reliable repairs that will stay fixed.

@youvsyou945 7 жыл бұрын

Thanks, I use good old kester 60/40 for everything but I'm sure to clean up all flux residue with swabs/alcohol. I need to try the eutectic stuff. Thanks for the great reply and thanks again for your awesome video!

@badloop 4 жыл бұрын

How did you disable the headphone jack so it doesn't cut off the control room and alt-outputs?

@RichardZeier 4 жыл бұрын

There's a wired .100 connector from the headphone jack that plugs into a header on the Monitor PCB. I removed the headphone jack along with the wired connector and found a plastic hole insert at a hardware store to plug the hole on the console. I then used a .100 crimp connector to make a shorting block to plug into the header on the Monitor PCB where the headphone connector used to plug into.

@paulbishop2161 6 жыл бұрын

Hi Richard, thoroughly enjoyed watching these videos, loads of useful information. I am planning on doing some mods to my Allen & Heath Saber desk, it's remarkably similar to the ghost. I would like to balance impede the direct outs like you've done here, I'm just not sure what value resistor I would need to use? How would I find out this info? I have the service manual and schematics, I'm just still learning about circuits. Thanks for any help you can give, Paul.

@RichardZeier 6 жыл бұрын

Hi Paul, Console manufacturers use different values of resistors on the output of the opamps. Neotek uses 47 ohms, Soundcraft 75 ohms, and others use 33, 50 or 51 ohms. This value should be consistent throughout your console schematics and can be found on any opamp feeding audio to the outside world. The idea of balanced impedance is to provide an equal resistance on each leg (pin 2 & 3) feeding the balanced input of any device connected to the console. This allows for maximum common mode noise rejection, which is the main purpose of balanced circuitry.

@paulbishop2161 6 жыл бұрын

Hey thanks so much for your detailed reply. So it turns out the output is 22ohms, which means I would need to use a resistor of the same value (22ohms). My desk has a TS jack for the direct out, so where would i solder the resistor if there's only 2 lugs? And would I use TRS or TS cables to go from my newly balance impeded direct outs to my balanced inputs on my interface? Thank-you very much.

@RichardZeier 6 жыл бұрын

The Ghost uses TRS jacks. Even though pin 3 was soldered to the ground plane, I was able to isolate the pad using a dremel cutting tool, and then soldered the resistor from pin 3 to ground. In your case you will have to install TRS jacks in place of the TS jacks to accomplish the same thing.

@jacsquared2966 9 жыл бұрын

Thanks for making these videos. Can anyone point me in the direction of how to mod the desk so the meter bridge displays signals at the line input?

@RichardZeier 9 жыл бұрын

I'm not close to the console or any documentation at the moment, but there is an internal jumper (0.100 computer type) for each channel that selects metering either the line/mic input or tape returns. Setting the jumper requires removing the bottom, so it's not convenient to change on a moments notice. My solution is to have them set for metering channel inputs which is most useful, however, when I want to meter tape returns, I engage the button next to the B Mix pot that sends the tape return to the channel which causes the meter to follow the tape return. Since I'm not near the console, I could be wrong about the exact configuration, but the important thing is that is does work.

@jacsquared2966 9 жыл бұрын

Hi, thanks for your reply, after some poking about on line I found that the mod is documented in the user manual, watching your video gave me the confidence to flip up the desk and take the bottom off and do the mod, thanks!

@maxdeiulis4784 7 жыл бұрын

Hi Richard, I am also going to do a similar work. I was wondering why not replacing the OPA1612 with the TL072 of the mic channel? Where did you replace the NE5532 in the master section with OPA1612? Any suggestion for the EQ opamp? OP275? Thanks a lot for your inspiring work.

@RichardZeier 7 жыл бұрын

Hi Max, I replaced the 5532 with OPA1612 in all the Master Section summing amps which are the the most critical points in the audio path. They are a little pricey considering the extra expense of mounting them on adapter pcbs, so I only used them where they would have the most benefit. I tried them in the mic pres, as well as OP275 to replace the TL072s but found both prone to oscillation (although I have a stand-alone mic pre with OPA1612 that works great). The OPA2134 worked best in the mic pres, and even then required a bias resistor change to completely stabilize the circuit. I left the EQs with TL072 for now, although I've done EQ mods for other people replacing all the caps with Wima polypropylene with good results.

@maxdeiulis4784 7 жыл бұрын

Which bias resistor did you change and what was the value if I may ask?

@RichardZeier 7 жыл бұрын

Someone else recently asked the same thing and unfortunately I can't find any notes and can't easily open the console to check. Basically, R12 and R13 forms a simple voltage divider that sets the bias voltage at around 8VDC. Changing the value of either resistor will move that voltage higher or lower. I think I inserted a pot to find a reliable voltage, but do not remember what value of resistor I settled on.

@maxdeiulis4784 7 жыл бұрын

Richard Zeier thanks so much for your help

@jaxsnmusic 8 жыл бұрын

and I was crazy enough think I could work on mine. are you close to connecticut? what would it cost to mod mine, or just bring it to specs?

@RichardZeier 8 жыл бұрын

Sorry, but I'm in LA and seldom do tech work outside of my own studio these days. There's a company in Nashville that does Ghost upgrades for around 5K$ which is much less than I would do it for.

@TheSoundtec 3 жыл бұрын

Hi Richard, could you please tell me how many amps your supply is and what does the Ghost require? Im trying to set up a new bench for working on consoles. I have a Dual 0-30v 3 amp ? I seen the ghost supply is around 4 amps. Thanks for your time.

@RichardZeier 3 жыл бұрын

I was given an overrated PSM-300 (300W) switching power supply with my console because I was working for Soundcraft at the time and snagged the very first Ghost delivered in North America, and that supply (from a bigger console) was all they had at the time. I believe they later shipped with 250W or 275W linear PSUs. A 250W supply should put out around 3.5A to each of the two rails (+17 & -17). The 48V is maybe 500mA. That sounds like a lot but probably has a safety margin, and in actuality, the console may draw considerably less then that in full operation. BTW: When I am talking about amps, I'm referring to the power supply output and not the 120VAC consumption which is quite different. I think you should be fine for testing a few channels. Even if you overload the supply it shouldn't hurt anything, assuming it has current limiting. I use a dual 0-30V 1A supply on my bench, of course I only test 1 module at a time, removed from the console. You must have a lot of space for your bench.

@TheSoundtec 3 жыл бұрын

@@RichardZeier I have two sides to my shop. A smaller bench well equipped and on the other side a 8' long bench for the bigger stuff. I use to service almost anything but now I only do audio, and looks like mixing consoles now also. Presently I have a Tascam DM-3200 on the bench and im working on updating the screen. My goal is also to find a way to add a Vga out on the digital console. Thanks again big time.!! PS I found a Ghost 32 in California but the guy wont ship to Canada.. and the search goes on.

@NikolausBrocke 8 жыл бұрын

Very interesting video. I own too a soundcraft ghost 32 with midi mute automation and an 24 expander. I am considdering recap it and put in better op ams. I am wondering how much this will improve the soundquality. How much will it cost to do it if I send you just the channels? I can buy a Amek Hendrix 40 channels for 4900€ in Germany. Just to compare values.

@RichardZeier 8 жыл бұрын

+Nikolaus Brocke Hi Nikolaus,It can make a significant difference in quality if you upgrade all of the signal paths, especially the master section along with the power supply. But to really appreciate it you need to go beyond the console and look at the monitors, studio wiring and the house electrical system. Of course, it's not inexpensive to replace hundreds of high-grade capacitors and opamps along with sockets and jacks and special mods, but if you would like to discuss details, you can contact me directly through the Rock It Science Audio website. www.rockitscienceaudio.com

@NikolausBrocke 8 жыл бұрын

+Richard Zeier, Hi Richard, thanks for your answer. You probably know these guys www.creationaudiolabs.com/#!ghost/c1q51 They inspired me to think of modding my Soundcraft. But I have to find a way to make it cheaper or leave it. I will contact you on your website.

@TheSoundtec 3 жыл бұрын

Your Ghost Videos are SUPERB ! wow that looks like a thin PCB, where did you find your mods. I would like to mod my boards also.. Appreciate your time.

@RichardZeier 3 жыл бұрын

The master section PCBs are double-sided fiberglass with through-hole plating, but unfortunately, the input modules are single-sided phenolic with no ground plane. Soundcraft could not have built a full featured console at that price point without some compromises. I worked for Martinsound in the mid 90s until about 2004 when they purchased Neotek. Since every console was built to order, I not only built and tested the consoles, but had input into designing mods to meet client's special requests. After leaving Martinsound I started Rock It Science Audio, where I continued to do independent work on Neotek and other consoles. After working on some great Neve and Trident consoles, I have always strived to get comparable performance out of my humble Ghost that I've owned since 96.

@TheSoundtec 3 жыл бұрын

@@RichardZeier well, I am looking for one of the Humble Ghosts for the simple reason that its a nice layout. If only it was modular. I have been a Tech for 40+ years so you guessed it I love modding also. I just thought there might be a site where the work was already Done. I want to replace my old Mackie 24.8bus. My goal was to find something modular as a project and eventually replace it, but all I seem to find with my budget are those monster 40 channel live boards that weigh 500Lbs. No thanks! lol . Thanks again GREAT videos.

@Theoobovril 2 жыл бұрын

Hi Richard, did you complete the book you were writing regarding the technical information that you wished to share.

@RichardZeier 2 жыл бұрын

Hi Theoobovril, Did I really say that I was writing a book? I must have been way less busy then. Maybe when I retire.

@amazighras3547 Жыл бұрын

Can I remove the aux and eq section without removing the inputs??

@RichardZeier Жыл бұрын

Hi Amazigh, The answer is yes. If you've yet to open the console, every channel is a complete circuit board from mic pre/EQ/Aux and B section containing all the pots and switches down to subgroup assignment. If you are referring to the input jacks, they are mounted on a small strip card along with the inserts and direct outs. There is a small ribbon cable connecting the two boards that can easily pulled out from either end. Richard

@lancyrankinskengloxreflexi9298 3 жыл бұрын

str8 fire

@oXjqd8ljGAUCx5Hy1oicy2Sc 6 ай бұрын

Where can I see an op-amp? What parts do you use?

@RichardZeier 6 ай бұрын

I don't remember where specifically I addressed opamps, but typically when removing the old opamps I install gold-plated machine-holed sockets and then insert the new opamp. As a rule, I replace TL072 chips with OPA2134 and the 5532 chips with LM4562. Hope that helps.

@oXjqd8ljGAUCx5Hy1oicy2Sc 6 ай бұрын

@@RichardZeier Does this mean that the opamps in the original ghost pre-amp were preamps using TL072, 5532?

@RichardZeier 6 ай бұрын

Yes, all of the opamps in the original Ghost are either TL072 for the high impedence low power circuits or LM5532 where low impedence outputs are required. @@oXjqd8ljGAUCx5Hy1oicy2Sc