Hello friends, I have a pyramid studio pro pr-6004 sound mixer, which has several burnt elements and unrecognizable ones, and I need the electronic diagram to be able to repair it. If someone owns it, I beg you to please provide it; Thanks in advance.
On the recommendation of "angel", the damage is in 2 resistors located in 2 of the potentiometers of the device, and for greater east ion for you, I send photos of the device 
Hello friends of the forum; I can think of an idea for the solution. To my problem:
In this audio mixer, and in the area of the potentiometers, the burned elements are 2 resistors, which were totally burned and no longer have values, and there is no circuit diagram of the device.
I am not a technician, I am just an amateur and the device is mine, and I have the following question:
? Can you test, placing resistors of different values, little by little, without "burning" the circuit again, until it works correctly?
The device is stereo. Were the components burned in both channels? Maybe with a photo of the area it would be more feasible to support you.
Hello Angel; I'm new and I have the photos, but I don't know how to do it in this forum; ? Could you guide me?
Edit the question with the pencil icon then in the toolbar an "image" icon appears to add it, select it in your folders and then "send to server" and save.
There is no diagram and with a single poorly focused and dark photo it will be difficult. But ... as a suggestion you should look at the other adjacent channels, if you see that they have a circuit and components that are symmetrical (because this is how the mixers work) then it is possible that another channel has more or less components with the same values. It is likely that you have IC that we call 8-pin operational checks if it is integrated circuits or transistors and comments.
Mr. Angel: Excuse me, but I couldn't get the system to accept me to upload the photos; it tells me that the file has more than 2 mb; that the URL of the image, and all the photos are from my camera; I don't understand what I'm doing wrong; I will continue to deal with patience; thanks friend, we'll talk soon !!!
Lord angel; Yes, the ic you refer to with 8 legs is the integrated one you use in that circuit and there are no transistors in the area.
Mr. Angel: because the images are uploaded to the forum, it has been inaccessible to me, an idea occurs to me; ? CAN I SEND YOU THE PHOTOS FOR YOUR WATHSAPP NUMBER?
We cannot publish personal data. Change the resolution of the photos, the best way is to change the size of them to a "smaller" 800x600. If you have already uploaded a photo I do not see any difficulty to upload more. Now, my question is if you know how to make a sketch or diagram, could you make one that would help us identify to which circuit these resistances belong.
This message is for angel; I finally got the photos to pass; As you can see, the damage is located in the potentiometer area; on the left you can see the "burned" space, where a resistance was coming and the serene resistance is on the other potentiometer on the right, next to the 8-legged ic
Lord angel the integrated circuit of 8 legs m5218al, I know, the rest of the resistors are fine, just those 2 resistors
I tell you, that circuit is powered by -15 on leg 4, +15 on leg 8. We need to check if the burned resistors belong to those feeds.
I know your effort is good but we need to know to which legs of the IC these resistances are connected.
If there is another equal IC circuit, check the values of the leg resistances 4 and 8.
The resistance of the homeland 4, is 1000 Homs, and that of the leg 8, is the one burned; the other resistance that is burned goes to leg 2; the resistance that goes to leg 4 is 1000 hms, and the other resistance that is burned goes to leg 2
OK there is your answer. Leg 4 and leg 8 are -15V + 15V supplies respectively. My dear the one that burned in leg 8 is 1000 ohms. Leg 2 is only negative feedback. Check the resistance of leg 2 from another IC with the same number and this is how your device looks.
In this case it can be resolved with the IC DATASHEET. I pass it to you by adding it for your reference.
I agree with you but I only pass a very bad photo, and try to pass more photos but the system asks me for the image URL and I don't know it; ? What I do?
Hello Angel; The first option that came to my mind when I saw the damage was to copy the circuit from the other channels, but unfortunately, no channel, both from the 3 microphones, and the other 2 audio input channels, where the 2 shorts that burned the 2 resistors of which I speak were presented; I will continue trying to send you the best photos that I can provide
Message to Angel Morales: Mr. Angel, as complementary data: the other opposite legs of the resistors are connected to wires that lead the signal to the other main circuit board.
Message to Angel Morales: both resistors pass the signal from the integrated circuit, through 2 filters of 10 UF, which I mentioned in the previous message, made 2 filters of .1 UF, located in the input circuit of microphone # 1, in the main card
This message is for Angel Morales:
Lord angel; I am not a technician, I am just an amateur, and due to my little experience, I committed a mistake by supplying the data of the location of the burned resistors, but then after breaking the circuit backlit, I realized of my mistake, so.if it is not very bothersome, I am going to provide the new data:
"One of the burned resistors, was welded to leg 1, of the untethered one and the other was welded to leg 7.! Please, please excuse my awkwardness!
Nothing happens. Both resistors correspond to the outputs and are surely of the same value both. But now the perspective obviously changes. I'm going to give you a diagram. You need to locate where these resistances arrive, because it is very strange that they have burned since they are outputs of the preamp and do not occupy only an audio signal at a few millivolts (mv). You should keep track of the circuit where they arrive.
Message to Angel Morales: Mr. Angel, here I have the new data: "Both resistors pass through 10uf filters, at 16 v., Before arriving at the legs of the integrated"
Mr. Angel; You are surprised at why these resistances were damaged! Before writing to you, I gave this device to a "technician", who only did a short circuit, causing the source of power to burn; Was that why they burned those resistances?
Message to Angel Morales: observing the circuit diagram that he sent me, and according to my little experience, I see in leg 1, a resistance of 1,000 hm, and in leg 7, I see a resistance, but worthless.
My last question, Mr. Angel, is: I must assume that this resistance is also 1,000 hm, and that this is the value of each resistance to change?
Very good, Mr. Angel, I will execute and finish the repair; When you test the equipment, I will write about the results thank you very much! !!!!
