Re: soundcraft spirit m4 mixer troubleshooting
see if you can find the stain where the water got in ..it might be a clue
see if you can find the stain where the water got in ..it might be a clue
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Re: soundcraft spirit m4 mixer troubleshooting
hi there I'm back,
It's too late to look for a stain, I've had it for so long sitting on the shelf, when I picked it up again I gave it a little brush. That was before knowing it got wet. But it was a good idea, thanks, I'm taking a note for the future.
Now, I had the signal tracer that was linked at the beginning, but I had to make a new one with a little potentiometer because the only battery amp I have right now is one of those eggy mp3 speakers, with no volume control and only one miniUSB input. Done.
So now i'm starting to test it, and for a first check I tried eq's and gain pots. And it sounds! ^^
Following the scheme I managed to find a couple of bad resistors for now, but I don't think that's the major trouble... I'll grab a cup of strong tea and get on it.Comment
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Re: soundcraft spirit m4 mixer troubleshooting
well done keep searching ..Comment
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Re: soundcraft spirit m4 mixer troubleshooting
hey, I took those resistors, but out of circuit they seem ok.. they are r592, r593 and their couples at the "P/B replaces mix"(master A page)
I also got a weird resistance reading at the resistors after the pan pots at mono at mono channels (i'm sticking to those for now), but just like the ones before mentioned, I believe the circuit is fooling me, since they all have the same readings...
Signal vanishes around the Opamps, they have power, but not much sound after r457(mono input cannel 1).. dunno if it is because of it's value or what.. tomorrow I'l tackle it again.Comment
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Re: soundcraft spirit m4 mixer troubleshooting
Sounds like progress
I recall 3-4 years ago, buying a Soundcraft FX16-II that had gotten something spilled on it (i might be wrong, but i do recall i bought it as faulty). Actually yeah it did, i'm starting to remember having to "patch up" some power traces going to opamps, that had been corroded by whatever it had "drank". I might've had to replace an opamp or two as well, but it's been a long time
Khron's Cave - Electronics - Audio - Teardowns - Mods - Repairs - Projects - Music - Rants - ShenanigansComment
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Re: soundcraft spirit m4 mixer troubleshooting
yes, it is. I am blissfull.
It's like a new dimension opening before my eyes! Now I got to a point where the signal goes bad, and further on I just can't keep tracking.
Is it the time to build a cable for signal injection? Is it as simple as picking up a jack and shoving a blocking cap and some resistors in between like the tracer?Comment
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Re: soundcraft spirit m4 mixer troubleshooting
For signal injection, (in)to where? Right after the point the signal gets lost, or..?Khron's Cave - Electronics - Audio - Teardowns - Mods - Repairs - Projects - Music - Rants - ShenanigansComment
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Re: soundcraft spirit m4 mixer troubleshooting
just a blocking cap should do it .
you really need to have control over the level . something with a vol control .Comment
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Re: soundcraft spirit m4 mixer troubleshooting
Yes khron,
to inject just past the bad point, so I can look for further trouble while I wait for the pieces to arrive... do you think that's a bad idea?
I allready put a little pot at the tracer, i'l just do the same on the injecter...Comment
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Re: soundcraft spirit m4 mixer troubleshooting
btw, the cap goes in series through right/left or through the negative lead?
or doesn't it mind?Comment
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Re: soundcraft spirit m4 mixer troubleshooting
cap on probe . negative/ground to chassis or ground point if floating groundComment
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Re: soundcraft spirit m4 mixer troubleshooting
Sssugar, i just did it the wrong way around.
I got a cut minijack lead that was chopped off, and connected the negative ground of it to the cap and the pot, and that was going to be neg/gnd, then the other 2 wires were going to be the probe.
If I wanted to have 2 probes, should I have a cap on each? would it be possible just like that, to test both L&R at the same time? I'll stick to one for now, just asking
thanks!Comment
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Re: soundcraft spirit m4 mixer troubleshooting
the idea of the cap is to block dc current going one way or the other .Comment
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Re: soundcraft spirit m4 mixer troubleshooting
Does that mean it doesn't matter the side?Comment
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Re: soundcraft spirit m4 mixer troubleshooting
just put a cap on the signal side . ground to ground .Comment
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Re: soundcraft spirit m4 mixer troubleshooting
Ok done, but it ain't doin much... i'm using the tracker to test it out, but it barely sounds, tried sliding the pots up&down and it's still pretty low, shall i try with an other cap? the one I put in is a 1uf.. maybe too much?Comment
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Re: soundcraft spirit m4 mixer troubleshooting
wait, showing it to a flatmate it seems to work now, I don't know what happened, maybe it was a bad contact, I'm starting to have too many wires on my desk.
that said, next is plugging it in to see.Comment
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Re: soundcraft spirit m4 mixer troubleshooting
well well,
Reading johnnydiaz's "How to check an OP AMP in circuit" thread, he checked for voltage at pin 8 he got 15.60vdc & pin 4 -15.35vdc
I instead have 10.4vdc on 8, and 0.7vdc on 4....Comment
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Re: soundcraft spirit m4 mixer troubleshooting
Is that the case on the opamp where the signal "ends"? And do you get the same measurement on the other opamps nearby?Khron's Cave - Electronics - Audio - Teardowns - Mods - Repairs - Projects - Music - Rants - ShenanigansComment
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Re: soundcraft spirit m4 mixer troubleshooting
what op amps are you checking ?Last edited by petehall347; 01-10-2017, 04:47 PM.Comment
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Hi all....I have been using my Behringer mixer quite comfortably for a number of years now and generally it's been trouble free apart from a replacement crossfader. Recently input three channel fader began to bleed a little and causing the mixer to light up like a Christmas tree! I realise the unit is ageing now and although I'd put some hours on it over the years it's not been abused. Following the issue I planned on replacing the faders and ordered the necessary parts. In the meantime whilst awaiting the replacements I continued to use the mixer up until the channel fader started to give feedback...
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Hi,
I bought a used Marantz SR5007 and it's giving me some issues that I can't seem to really place. It functions well in most settings, ARC mostly works, it has no issues driving my speakers in any of the digital input modes, but I'm having issues running analog inputs in direct or pure direct mode. For some reason in this mode there's distortion for every volume increment I give it, but once the volume is stable it has no issues. Muting creates a loud pop, switching to another source also causes a pop and so does turning off the amp in that mode. Again, no issue in the digital modes.... -
Hello dear audio friends.
I am feverishly looking for the full electronic schematic (not a block diagram) of the RCF type M18 digital audio mixer.
The device does not make a WIFI connection with my Apple tablet and yet I have already installed the recent app on it.
I suspect that there is a problem in the mixer itself with the WIFI card and of course I would like to see this on an extensive schedule before opening the device.
Thanks in advance if anyone can help me with this schematic.
Of course, all information about this digital mixer and possibly references...07-24-2023, 06:40 AM -
Hello from France,
mon2 kindly advised me to post a thread to ask the question(s) I'm concerned about. I'm new to the forum and I'm looking for practical courses for troubleshooting pc motherboards especially laptops in Europe, if possible in France. I have been a computer network system administrator and a corrector of administration modules for automated programs under Unix. But I really miss the practical "ops" side of troubleshooting. So I would like to start from the beginning: 1.8V, 3.3V, 5V and 19V tests for example, etc...
Do you think this is feasible for me? I... -
I am planning to buy myself a new mixer. Yamaha MG12U or XU(not sure) and I always like to take a look inside of mixer to check how it looks, if caps are low quality and other stuff.
I manage to find some teardown video on youtube but video name is saying MG12XU, but when you look at video on mixer it's MG12U.
And when I google those two models they have different PSUs one have cheap low quality caps, and other is way better with quality ones Nichicon. So I am confused now from what model exactly is that better PSU??
I google a little and found that there is this part number...
Comment